diff --git a/ableos/shitty_code_to_rewrite/shutdown.rs b/ableos/shitty_code_to_rewrite/shutdown.rs deleted file mode 100644 index 3514d1b..0000000 --- a/ableos/shitty_code_to_rewrite/shutdown.rs +++ /dev/null @@ -1,27 +0,0 @@ -#[repr(C)] -pub struct ShutterDowner { - smi_cmd: u32, - acpi_enable: u8, - acpi_disable: u8, - pm1a_cnt: u32, - pm1b_cnt: u32, - slp_typa: u16, - slp_typb: u16, - slp_en: u16, - scii_en: u16, - pm1_cnt_len: u8, -} - -pub structRSDPtr { - signature: [u8; 8], - checksum: u8, - oem_id: [u8; 6], - revision: u8, - rsdt_address: u32, -} - -struct FACP { - signature: [u8; 4], - length: u32, - -} \ No newline at end of file diff --git a/ableos/shitty_code_to_rewrite/shutdown_in_c.c b/ableos/shitty_code_to_rewrite/shutdown_in_c.c deleted file mode 100644 index 84fa838..0000000 --- a/ableos/shitty_code_to_rewrite/shutdown_in_c.c +++ /dev/null @@ -1,302 +0,0 @@ -// // -// // here is the slighlty complicated ACPI poweroff code -// // - -#include -#include -#include -#include -#include - -dword *SMI_CMD; -byte ACPI_ENABLE; -byte ACPI_DISABLE; -dword *PM1a_CNT; -dword *PM1b_CNT; -word SLP_TYPa; -word SLP_TYPb; -word SLP_EN; -word SCI_EN; -byte PM1_CNT_LEN; - -struct RSDPtr -{ - byte Signature[8]; - byte CheckSum; - byte OemID[6]; - byte Revision; - dword *RsdtAddress; -}; - -struct FACP -{ - byte Signature[4]; - dword Length; - byte unneded1[40 - 8]; - dword *DSDT; - byte unneded2[48 - 44]; - dword *SMI_CMD; - byte ACPI_ENABLE; - byte ACPI_DISABLE; - byte unneded3[64 - 54]; - dword *PM1a_CNT_BLK; - dword *PM1b_CNT_BLK; - byte unneded4[89 - 72]; - byte PM1_CNT_LEN; -}; - -// check if the given address has a valid header -unsigned int *acpiCheckRSDPtr(unsigned int *ptr) -{ - char *sig = "RSD PTR "; - struct RSDPtr *rsdp = (struct RSDPtr *)ptr; - byte *bptr; - byte check = 0; - int i; - - if (memcmp(sig, rsdp, 8) == 0) - { - // check checksum rsdpd - bptr = (byte *)ptr; - for (i = 0; i < sizeof(struct RSDPtr); i++) - { - check += *bptr; - bptr++; - } - - // found valid rsdpd - if (check == 0) - { - /* - if (desc->Revision == 0) - wrstr("acpi 1"); - else - wrstr("acpi 2"); - */ - return (unsigned int *)rsdp->RsdtAddress; - } - } - - return NULL; -} - -// finds the acpi header and returns the address of the rsdt -unsigned int *acpiGetRSDPtr(void) -{ - unsigned int *addr; - unsigned int *rsdp; - - // search below the 1mb mark for RSDP signature - for (addr = (unsigned int *)0x000E0000; (int)addr < 0x00100000; addr += 0x10 / sizeof(addr)) - { - rsdp = acpiCheckRSDPtr(addr); - if (rsdp != NULL) - return rsdp; - } - - // at address 0x40:0x0E is the RM segment of the ebda - int ebda = *((short *)0x40E); // get pointer - ebda = ebda * 0x10 & 0x000FFFFF; // transform segment into linear address - - // search Extended BIOS Data Area for the Root System Description Pointer signature - for (addr = (unsigned int *)ebda; (int)addr < ebda + 1024; addr += 0x10 / sizeof(addr)) - { - rsdp = acpiCheckRSDPtr(addr); - if (rsdp != NULL) - return rsdp; - } - - return NULL; -} - -// checks for a given header and validates checksum -int acpiCheckHeader(unsigned int *ptr, char *sig) -{ - if (memcmp(ptr, sig, 4) == 0) - { - char *checkPtr = (char *)ptr; - int len = *(ptr + 1); - char check = 0; - while (0 < len--) - { - check += *checkPtr; - checkPtr++; - } - if (check == 0) - return 0; - } - return -1; -} - -int acpiEnable(void) -{ - // check if acpi is enabled - if ((inw((unsigned int)PM1a_CNT) & SCI_EN) == 0) - { - // check if acpi can be enabled - if (SMI_CMD != 0 && ACPI_ENABLE != 0) - { - outb((unsigned int)SMI_CMD, ACPI_ENABLE); // send acpi enable command - // give 3 seconds time to enable acpi - int i; - for (i = 0; i < 300; i++) - { - if ((inw((unsigned int)PM1a_CNT) & SCI_EN) == 1) - break; - sleep(10); - } - if (PM1b_CNT != 0) - for (; i < 300; i++) - { - if ((inw((unsigned int)PM1b_CNT) & SCI_EN) == 1) - break; - sleep(10); - } - if (i < 300) - { - wrstr("enabled acpi.\n"); - return 0; - } - else - { - wrstr("couldn't enable acpi.\n"); - return -1; - } - } - else - { - wrstr("no known way to enable acpi.\n"); - return -1; - } - } - else - { - //wrstr("acpi was already enabled.\n"); - return 0; - } -} - -// -// bytecode of the \_S5 object -// ----------------------------------------- -// | (optional) | | | | -// NameOP | \ | _ | S | 5 | _ -// 08 | 5A | 5F | 53 | 35 | 5F -// -// ----------------------------------------------------------------------------------------------------------- -// | | | ( SLP_TYPa ) | ( SLP_TYPb ) | ( Reserved ) | (Reserved ) -// PackageOP | PkgLength | NumElements | byteprefix Num | byteprefix Num | byteprefix Num | byteprefix Num -// 12 | 0A | 04 | 0A 05 | 0A 05 | 0A 05 | 0A 05 -// -//----this-structure-was-also-seen---------------------- -// PackageOP | PkgLength | NumElements | -// 12 | 06 | 04 | 00 00 00 00 -// -// (Pkglength bit 6-7 encode additional PkgLength bytes [shouldn't be the case here]) -// -int initAcpi(void) -{ - unsigned int *ptr = acpiGetRSDPtr(); - - // check if address is correct ( if acpi is available on this pc ) - if (ptr != NULL && acpiCheckHeader(ptr, "RSDT") == 0) - { - // the RSDT contains an unknown number of pointers to acpi tables - int entrys = *(ptr + 1); - entrys = (entrys - 36) / 4; - ptr += 36 / 4; // skip header information - - while (0 < entrys--) - { - // check if the desired table is reached - if (acpiCheckHeader((unsigned int *)*ptr, "FACP") == 0) - { - entrys = -2; - struct FACP *facp = (struct FACP *)*ptr; - if (acpiCheckHeader((unsigned int *)facp->DSDT, "DSDT") == 0) - { - // search the \_S5 package in the DSDT - char *S5Addr = (char *)facp->DSDT + 36; // skip header - int dsdtLength = *(facp->DSDT + 1) - 36; - while (0 < dsdtLength--) - { - if (memcmp(S5Addr, "_S5_", 4) == 0) - break; - S5Addr++; - } - // check if \_S5 was found - if (dsdtLength > 0) - { - // check for valid AML structure - if ((*(S5Addr - 1) == 0x08 || (*(S5Addr - 2) == 0x08 && *(S5Addr - 1) == '\\')) && *(S5Addr + 4) == 0x12) - { - S5Addr += 5; - // calculate PkgLength size - S5Addr += ((*S5Addr &0xC0)>>6) +2; - - if (*S5Addr == 0x0A) - S5Addr++; // skip byteprefix - SLP_TYPa = *(S5Addr) << 10; - S5Addr++; - - if (*S5Addr == 0x0A) - S5Addr++; // skip byteprefix - SLP_TYPb = *(S5Addr) << 10; - - SMI_CMD = facp->SMI_CMD; - - ACPI_ENABLE = facp->ACPI_ENABLE; - ACPI_DISABLE = facp->ACPI_DISABLE; - - PM1a_CNT = facp->PM1a_CNT_BLK; - PM1b_CNT = facp->PM1b_CNT_BLK; - - PM1_CNT_LEN = facp->PM1_CNT_LEN; - - SLP_EN = 1 << 13; - SCI_EN = 1; - - return 0; - } - else - { - wrstr("\\_S5 parse error.\n"); - } - } - else - { - wrstr("\\_S5 not present.\n"); - } - } - else - { - wrstr("DSDT invalid.\n"); - } - } - ptr++; - } - wrstr("no valid FACP present.\n"); - } - else - { - wrstr("no acpi.\n"); - } - - return -1; -} - -void acpiPowerOff(void) -{ - // SCI_EN is set to 1 if acpi shutdown is possible - if (SCI_EN == 0) - return; - - acpiEnable(); - - // send the shutdown command - outw((unsigned int)PM1a_CNT, SLP_TYPa | SLP_EN); - if (PM1b_CNT != 0) - outw((unsigned int)PM1b_CNT, SLP_TYPb | SLP_EN); - - wrstr("acpi poweroff failed.\n"); -} diff --git a/ableos/shitty_code_to_rewrite/signal.c b/ableos/shitty_code_to_rewrite/signal.c deleted file mode 100644 index 9b894ac..0000000 --- a/ableos/shitty_code_to_rewrite/signal.c +++ /dev/null @@ -1,4947 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * linux/kernel/signal.c - * - * Copyright (C) 1991, 1992 Linus Torvalds - * - * 1997-11-02 Modified for POSIX.1b signals by Richard Henderson - * - * 2003-06-02 Jim Houston - Concurrent Computer Corp. - * Changes to use preallocated sigqueue structures - * to allow signals to be sent reliably. - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#define CREATE_TRACE_POINTS -#include - -#include -#include -#include -#include -#include -#include /* for syscall_get_* */ - -/* - * SLAB caches for signal bits. - */ - -static struct kmem_cache *sigqueue_cachep; - -int print_fatal_signals __read_mostly; - -static void __user *sig_handler(struct task_struct *t, int sig) -{ - return t->sighand->action[sig - 1].sa.sa_handler; -} - -static inline bool sig_handler_ignored(void __user *handler, int sig) -{ - /* Is it explicitly or implicitly ignored? */ - return handler == SIG_IGN || - (handler == SIG_DFL && sig_kernel_ignore(sig)); -} - -static bool sig_task_ignored(struct task_struct *t, int sig, bool force) -{ - void __user *handler; - - handler = sig_handler(t, sig); - - /* SIGKILL and SIGSTOP may not be sent to the global init */ - if (unlikely(is_global_init(t) && sig_kernel_only(sig))) - return true; - - if (unlikely(t->signal->flags & SIGNAL_UNKILLABLE) && - handler == SIG_DFL && !(force && sig_kernel_only(sig))) - return true; - - /* Only allow kernel generated signals to this kthread */ - if (unlikely((t->flags & PF_KTHREAD) && - (handler == SIG_KTHREAD_KERNEL) && !force)) - return true; - - return sig_handler_ignored(handler, sig); -} - -static bool sig_ignored(struct task_struct *t, int sig, bool force) -{ - /* - * Blocked signals are never ignored, since the - * signal handler may change by the time it is - * unblocked. - */ - if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig)) - return false; - - /* - * Tracers may want to know about even ignored signal unless it - * is SIGKILL which can't be reported anyway but can be ignored - * by SIGNAL_UNKILLABLE task. - */ - if (t->ptrace && sig != SIGKILL) - return false; - - return sig_task_ignored(t, sig, force); -} - -/* - * Re-calculate pending state from the set of locally pending - * signals, globally pending signals, and blocked signals. - */ -static inline bool has_pending_signals(sigset_t *signal, sigset_t *blocked) -{ - unsigned long ready; - long i; - - switch (_NSIG_WORDS) - { - default: - for (i = _NSIG_WORDS, ready = 0; --i >= 0;) - ready |= signal->sig[i] & ~blocked->sig[i]; - break; - - case 4: - ready = signal->sig[3] & ~blocked->sig[3]; - ready |= signal->sig[2] & ~blocked->sig[2]; - ready |= signal->sig[1] & ~blocked->sig[1]; - ready |= signal->sig[0] & ~blocked->sig[0]; - break; - - case 2: - ready = signal->sig[1] & ~blocked->sig[1]; - ready |= signal->sig[0] & ~blocked->sig[0]; - break; - - case 1: - ready = signal->sig[0] & ~blocked->sig[0]; - } - return ready != 0; -} - -#define PENDING(p, b) has_pending_signals(&(p)->signal, (b)) - -static bool recalc_sigpending_tsk(struct task_struct *t) -{ - if ((t->jobctl & (JOBCTL_PENDING_MASK | JOBCTL_TRAP_FREEZE)) || - PENDING(&t->pending, &t->blocked) || - PENDING(&t->signal->shared_pending, &t->blocked) || - cgroup_task_frozen(t)) - { - set_tsk_thread_flag(t, TIF_SIGPENDING); - return true; - } - - /* - * We must never clear the flag in another thread, or in current - * when it's possible the current syscall is returning -ERESTART*. - * So we don't clear it here, and only callers who know they should do. - */ - return false; -} - -/* - * After recalculating TIF_SIGPENDING, we need to make sure the task wakes up. - * This is superfluous when called on current, the wakeup is a harmless no-op. - */ -void recalc_sigpending_and_wake(struct task_struct *t) -{ - if (recalc_sigpending_tsk(t)) - signal_wake_up(t, 0); -} - -void recalc_sigpending(void) -{ - if (!recalc_sigpending_tsk(current) && !freezing(current)) - clear_thread_flag(TIF_SIGPENDING); -} -EXPORT_SYMBOL(recalc_sigpending); - -void calculate_sigpending(void) -{ - /* Have any signals or users of TIF_SIGPENDING been delayed - * until after fork? - */ - spin_lock_irq(¤t->sighand->siglock); - set_tsk_thread_flag(current, TIF_SIGPENDING); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); -} - -/* Given the mask, find the first available signal that should be serviced. */ - -#define SYNCHRONOUS_MASK \ - (sigmask(SIGSEGV) | sigmask(SIGBUS) | sigmask(SIGILL) | \ - sigmask(SIGTRAP) | sigmask(SIGFPE) | sigmask(SIGSYS)) - -int next_signal(struct sigpending *pending, sigset_t *mask) -{ - unsigned long i, *s, *m, x; - int sig = 0; - - s = pending->signal.sig; - m = mask->sig; - - /* - * Handle the first word specially: it contains the - * synchronous signals that need to be dequeued first. - */ - x = *s & ~*m; - if (x) - { - if (x & SYNCHRONOUS_MASK) - x &= SYNCHRONOUS_MASK; - sig = ffz(~x) + 1; - return sig; - } - - switch (_NSIG_WORDS) - { - default: - for (i = 1; i < _NSIG_WORDS; ++i) - { - x = *++s & ~*++m; - if (!x) - continue; - sig = ffz(~x) + i * _NSIG_BPW + 1; - break; - } - break; - - case 2: - x = s[1] & ~m[1]; - if (!x) - break; - sig = ffz(~x) + _NSIG_BPW + 1; - break; - - case 1: - /* Nothing to do */ - break; - } - - return sig; -} - -static inline void print_dropped_signal(int sig) -{ - static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10); - - if (!print_fatal_signals) - return; - - if (!__ratelimit(&ratelimit_state)) - return; - - pr_info("%s/%d: reached RLIMIT_SIGPENDING, dropped signal %d\n", - current->comm, current->pid, sig); -} - -/** - * task_set_jobctl_pending - set jobctl pending bits - * @task: target task - * @mask: pending bits to set - * - * Clear @mask from @task->jobctl. @mask must be subset of - * %JOBCTL_PENDING_MASK | %JOBCTL_STOP_CONSUME | %JOBCTL_STOP_SIGMASK | - * %JOBCTL_TRAPPING. If stop signo is being set, the existing signo is - * cleared. If @task is already being killed or exiting, this function - * becomes noop. - * - * CONTEXT: - * Must be called with @task->sighand->siglock held. - * - * RETURNS: - * %true if @mask is set, %false if made noop because @task was dying. - */ -bool task_set_jobctl_pending(struct task_struct *task, unsigned long mask) -{ - BUG_ON(mask & ~(JOBCTL_PENDING_MASK | JOBCTL_STOP_CONSUME | - JOBCTL_STOP_SIGMASK | JOBCTL_TRAPPING)); - BUG_ON((mask & JOBCTL_TRAPPING) && !(mask & JOBCTL_PENDING_MASK)); - - if (unlikely(fatal_signal_pending(task) || (task->flags & PF_EXITING))) - return false; - - if (mask & JOBCTL_STOP_SIGMASK) - task->jobctl &= ~JOBCTL_STOP_SIGMASK; - - task->jobctl |= mask; - return true; -} - -/** - * task_clear_jobctl_trapping - clear jobctl trapping bit - * @task: target task - * - * If JOBCTL_TRAPPING is set, a ptracer is waiting for us to enter TRACED. - * Clear it and wake up the ptracer. Note that we don't need any further - * locking. @task->siglock guarantees that @task->parent points to the - * ptracer. - * - * CONTEXT: - * Must be called with @task->sighand->siglock held. - */ -void task_clear_jobctl_trapping(struct task_struct *task) -{ - if (unlikely(task->jobctl & JOBCTL_TRAPPING)) - { - task->jobctl &= ~JOBCTL_TRAPPING; - smp_mb(); /* advised by wake_up_bit() */ - wake_up_bit(&task->jobctl, JOBCTL_TRAPPING_BIT); - } -} - -/** - * task_clear_jobctl_pending - clear jobctl pending bits - * @task: target task - * @mask: pending bits to clear - * - * Clear @mask from @task->jobctl. @mask must be subset of - * %JOBCTL_PENDING_MASK. If %JOBCTL_STOP_PENDING is being cleared, other - * STOP bits are cleared together. - * - * If clearing of @mask leaves no stop or trap pending, this function calls - * task_clear_jobctl_trapping(). - * - * CONTEXT: - * Must be called with @task->sighand->siglock held. - */ -void task_clear_jobctl_pending(struct task_struct *task, unsigned long mask) -{ - BUG_ON(mask & ~JOBCTL_PENDING_MASK); - - if (mask & JOBCTL_STOP_PENDING) - mask |= JOBCTL_STOP_CONSUME | JOBCTL_STOP_DEQUEUED; - - task->jobctl &= ~mask; - - if (!(task->jobctl & JOBCTL_PENDING_MASK)) - task_clear_jobctl_trapping(task); -} - -/** - * task_participate_group_stop - participate in a group stop - * @task: task participating in a group stop - * - * @task has %JOBCTL_STOP_PENDING set and is participating in a group stop. - * Group stop states are cleared and the group stop count is consumed if - * %JOBCTL_STOP_CONSUME was set. If the consumption completes the group - * stop, the appropriate `SIGNAL_*` flags are set. - * - * CONTEXT: - * Must be called with @task->sighand->siglock held. - * - * RETURNS: - * %true if group stop completion should be notified to the parent, %false - * otherwise. - */ -static bool task_participate_group_stop(struct task_struct *task) -{ - struct signal_struct *sig = task->signal; - bool consume = task->jobctl & JOBCTL_STOP_CONSUME; - - WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING)); - - task_clear_jobctl_pending(task, JOBCTL_STOP_PENDING); - - if (!consume) - return false; - - if (!WARN_ON_ONCE(sig->group_stop_count == 0)) - sig->group_stop_count--; - - /* - * Tell the caller to notify completion iff we are entering into a - * fresh group stop. Read comment in do_signal_stop() for details. - */ - if (!sig->group_stop_count && !(sig->flags & SIGNAL_STOP_STOPPED)) - { - signal_set_stop_flags(sig, SIGNAL_STOP_STOPPED); - return true; - } - return false; -} - -void task_join_group_stop(struct task_struct *task) -{ - unsigned long mask = current->jobctl & JOBCTL_STOP_SIGMASK; - struct signal_struct *sig = current->signal; - - if (sig->group_stop_count) - { - sig->group_stop_count++; - mask |= JOBCTL_STOP_CONSUME; - } - else if (!(sig->flags & SIGNAL_STOP_STOPPED)) - return; - - /* Have the new thread join an on-going signal group stop */ - task_set_jobctl_pending(task, mask | JOBCTL_STOP_PENDING); -} - -/* - * allocate a new signal queue record - * - this may be called without locks if and only if t == current, otherwise an - * appropriate lock must be held to stop the target task from exiting - */ -static struct sigqueue * -__sigqueue_alloc(int sig, struct task_struct *t, gfp_t gfp_flags, - int override_rlimit, const unsigned int sigqueue_flags) -{ - struct sigqueue *q = NULL; - struct ucounts *ucounts = NULL; - long sigpending; - - /* - * Protect access to @t credentials. This can go away when all - * callers hold rcu read lock. - * - * NOTE! A pending signal will hold on to the user refcount, - * and we get/put the refcount only when the sigpending count - * changes from/to zero. - */ - rcu_read_lock(); - ucounts = task_ucounts(t); - sigpending = inc_rlimit_get_ucounts(ucounts, UCOUNT_RLIMIT_SIGPENDING); - rcu_read_unlock(); - if (!sigpending) - return NULL; - - if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) - { - q = kmem_cache_alloc(sigqueue_cachep, gfp_flags); - } - else - { - print_dropped_signal(sig); - } - - if (unlikely(q == NULL)) - { - dec_rlimit_put_ucounts(ucounts, UCOUNT_RLIMIT_SIGPENDING); - } - else - { - INIT_LIST_HEAD(&q->list); - q->flags = sigqueue_flags; - q->ucounts = ucounts; - } - return q; -} - -static void __sigqueue_free(struct sigqueue *q) -{ - if (q->flags & SIGQUEUE_PREALLOC) - return; - if (q->ucounts) - { - dec_rlimit_put_ucounts(q->ucounts, UCOUNT_RLIMIT_SIGPENDING); - q->ucounts = NULL; - } - kmem_cache_free(sigqueue_cachep, q); -} - -void flush_sigqueue(struct sigpending *queue) -{ - struct sigqueue *q; - - sigemptyset(&queue->signal); - while (!list_empty(&queue->list)) - { - q = list_entry(queue->list.next, struct sigqueue, list); - list_del_init(&q->list); - __sigqueue_free(q); - } -} - -/* - * Flush all pending signals for this kthread. - */ -void flush_signals(struct task_struct *t) -{ - unsigned long flags; - - spin_lock_irqsave(&t->sighand->siglock, flags); - clear_tsk_thread_flag(t, TIF_SIGPENDING); - flush_sigqueue(&t->pending); - flush_sigqueue(&t->signal->shared_pending); - spin_unlock_irqrestore(&t->sighand->siglock, flags); -} -EXPORT_SYMBOL(flush_signals); - -#ifdef CONFIG_POSIX_TIMERS -static void __flush_itimer_signals(struct sigpending *pending) -{ - sigset_t signal, retain; - struct sigqueue *q, *n; - - signal = pending->signal; - sigemptyset(&retain); - - list_for_each_entry_safe(q, n, &pending->list, list) - { - int sig = q->info.si_signo; - - if (likely(q->info.si_code != SI_TIMER)) - { - sigaddset(&retain, sig); - } - else - { - sigdelset(&signal, sig); - list_del_init(&q->list); - __sigqueue_free(q); - } - } - - sigorsets(&pending->signal, &signal, &retain); -} - -void flush_itimer_signals(void) -{ - struct task_struct *tsk = current; - unsigned long flags; - - spin_lock_irqsave(&tsk->sighand->siglock, flags); - __flush_itimer_signals(&tsk->pending); - __flush_itimer_signals(&tsk->signal->shared_pending); - spin_unlock_irqrestore(&tsk->sighand->siglock, flags); -} -#endif - -void ignore_signals(struct task_struct *t) -{ - int i; - - for (i = 0; i < _NSIG; ++i) - t->sighand->action[i].sa.sa_handler = SIG_IGN; - - flush_signals(t); -} - -/* - * Flush all handlers for a task. - */ - -void flush_signal_handlers(struct task_struct *t, int force_default) -{ - int i; - struct k_sigaction *ka = &t->sighand->action[0]; - for (i = _NSIG; i != 0; i--) - { - if (force_default || ka->sa.sa_handler != SIG_IGN) - ka->sa.sa_handler = SIG_DFL; - ka->sa.sa_flags = 0; -#ifdef __ARCH_HAS_SA_RESTORER - ka->sa.sa_restorer = NULL; -#endif - sigemptyset(&ka->sa.sa_mask); - ka++; - } -} - -bool unhandled_signal(struct task_struct *tsk, int sig) -{ - void __user *handler = tsk->sighand->action[sig - 1].sa.sa_handler; - if (is_global_init(tsk)) - return true; - - if (handler != SIG_IGN && handler != SIG_DFL) - return false; - - /* if ptraced, let the tracer determine */ - return !tsk->ptrace; -} - -static void collect_signal(int sig, struct sigpending *list, kernel_siginfo_t *info, - bool *resched_timer) -{ - struct sigqueue *q, *first = NULL; - - /* - * Collect the siginfo appropriate to this signal. Check if - * there is another siginfo for the same signal. - */ - list_for_each_entry(q, &list->list, list) - { - if (q->info.si_signo == sig) - { - if (first) - goto still_pending; - first = q; - } - } - - sigdelset(&list->signal, sig); - - if (first) - { - still_pending: - list_del_init(&first->list); - copy_siginfo(info, &first->info); - - *resched_timer = - (first->flags & SIGQUEUE_PREALLOC) && - (info->si_code == SI_TIMER) && - (info->si_sys_private); - - __sigqueue_free(first); - } - else - { - /* - * Ok, it wasn't in the queue. This must be - * a fast-pathed signal or we must have been - * out of queue space. So zero out the info. - */ - clear_siginfo(info); - info->si_signo = sig; - info->si_errno = 0; - info->si_code = SI_USER; - info->si_pid = 0; - info->si_uid = 0; - } -} - -static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, - kernel_siginfo_t *info, bool *resched_timer) -{ - int sig = next_signal(pending, mask); - - if (sig) - collect_signal(sig, pending, info, resched_timer); - return sig; -} - -/* - * Dequeue a signal and return the element to the caller, which is - * expected to free it. - * - * All callers have to hold the siglock. - */ -int dequeue_signal(struct task_struct *tsk, sigset_t *mask, kernel_siginfo_t *info) -{ - bool resched_timer = false; - int signr; - - /* We only dequeue private signals from ourselves, we don't let - * signalfd steal them - */ - signr = __dequeue_signal(&tsk->pending, mask, info, &resched_timer); - if (!signr) - { - signr = __dequeue_signal(&tsk->signal->shared_pending, - mask, info, &resched_timer); -#ifdef CONFIG_POSIX_TIMERS - /* - * itimer signal ? - * - * itimers are process shared and we restart periodic - * itimers in the signal delivery path to prevent DoS - * attacks in the high resolution timer case. This is - * compliant with the old way of self-restarting - * itimers, as the SIGALRM is a legacy signal and only - * queued once. Changing the restart behaviour to - * restart the timer in the signal dequeue path is - * reducing the timer noise on heavy loaded !highres - * systems too. - */ - if (unlikely(signr == SIGALRM)) - { - struct hrtimer *tmr = &tsk->signal->real_timer; - - if (!hrtimer_is_queued(tmr) && - tsk->signal->it_real_incr != 0) - { - hrtimer_forward(tmr, tmr->base->get_time(), - tsk->signal->it_real_incr); - hrtimer_restart(tmr); - } - } -#endif - } - - recalc_sigpending(); - if (!signr) - return 0; - - if (unlikely(sig_kernel_stop(signr))) - { - /* - * Set a marker that we have dequeued a stop signal. Our - * caller might release the siglock and then the pending - * stop signal it is about to process is no longer in the - * pending bitmasks, but must still be cleared by a SIGCONT - * (and overruled by a SIGKILL). So those cases clear this - * shared flag after we've set it. Note that this flag may - * remain set after the signal we return is ignored or - * handled. That doesn't matter because its only purpose - * is to alert stop-signal processing code when another - * processor has come along and cleared the flag. - */ - current->jobctl |= JOBCTL_STOP_DEQUEUED; - } -#ifdef CONFIG_POSIX_TIMERS - if (resched_timer) - { - /* - * Release the siglock to ensure proper locking order - * of timer locks outside of siglocks. Note, we leave - * irqs disabled here, since the posix-timers code is - * about to disable them again anyway. - */ - spin_unlock(&tsk->sighand->siglock); - posixtimer_rearm(info); - spin_lock(&tsk->sighand->siglock); - - /* Don't expose the si_sys_private value to userspace */ - info->si_sys_private = 0; - } -#endif - return signr; -} -EXPORT_SYMBOL_GPL(dequeue_signal); - -static int dequeue_synchronous_signal(kernel_siginfo_t *info) -{ - struct task_struct *tsk = current; - struct sigpending *pending = &tsk->pending; - struct sigqueue *q, *sync = NULL; - - /* - * Might a synchronous signal be in the queue? - */ - if (!((pending->signal.sig[0] & ~tsk->blocked.sig[0]) & SYNCHRONOUS_MASK)) - return 0; - - /* - * Return the first synchronous signal in the queue. - */ - list_for_each_entry(q, &pending->list, list) - { - /* Synchronous signals have a positive si_code */ - if ((q->info.si_code > SI_USER) && - (sigmask(q->info.si_signo) & SYNCHRONOUS_MASK)) - { - sync = q; - goto next; - } - } - return 0; -next: - /* - * Check if there is another siginfo for the same signal. - */ - list_for_each_entry_continue(q, &pending->list, list) - { - if (q->info.si_signo == sync->info.si_signo) - goto still_pending; - } - - sigdelset(&pending->signal, sync->info.si_signo); - recalc_sigpending(); -still_pending: - list_del_init(&sync->list); - copy_siginfo(info, &sync->info); - __sigqueue_free(sync); - return info->si_signo; -} - -/* - * Tell a process that it has a new active signal.. - * - * NOTE! we rely on the previous spin_lock to - * lock interrupts for us! We can only be called with - * "siglock" held, and the local interrupt must - * have been disabled when that got acquired! - * - * No need to set need_resched since signal event passing - * goes through ->blocked - */ -void signal_wake_up_state(struct task_struct *t, unsigned int state) -{ - set_tsk_thread_flag(t, TIF_SIGPENDING); - /* - * TASK_WAKEKILL also means wake it up in the stopped/traced/killable - * case. We don't check t->state here because there is a race with it - * executing another processor and just now entering stopped state. - * By using wake_up_state, we ensure the process will wake up and - * handle its death signal. - */ - if (!wake_up_state(t, state | TASK_INTERRUPTIBLE)) - kick_process(t); -} - -/* - * Remove signals in mask from the pending set and queue. - * Returns 1 if any signals were found. - * - * All callers must be holding the siglock. - */ -static void flush_sigqueue_mask(sigset_t *mask, struct sigpending *s) -{ - struct sigqueue *q, *n; - sigset_t m; - - sigandsets(&m, mask, &s->signal); - if (sigisemptyset(&m)) - return; - - sigandnsets(&s->signal, &s->signal, mask); - list_for_each_entry_safe(q, n, &s->list, list) - { - if (sigismember(mask, q->info.si_signo)) - { - list_del_init(&q->list); - __sigqueue_free(q); - } - } -} - -static inline int is_si_special(const struct kernel_siginfo *info) -{ - return info <= SEND_SIG_PRIV; -} - -static inline bool si_fromuser(const struct kernel_siginfo *info) -{ - return info == SEND_SIG_NOINFO || - (!is_si_special(info) && SI_FROMUSER(info)); -} - -/* - * called with RCU read lock from check_kill_permission() - */ -static bool kill_ok_by_cred(struct task_struct *t) -{ - const struct cred *cred = current_cred(); - const struct cred *tcred = __task_cred(t); - - return uid_eq(cred->euid, tcred->suid) || - uid_eq(cred->euid, tcred->uid) || - uid_eq(cred->uid, tcred->suid) || - uid_eq(cred->uid, tcred->uid) || - ns_capable(tcred->user_ns, CAP_KILL); -} - -/* - * Bad permissions for sending the signal - * - the caller must hold the RCU read lock - */ -static int check_kill_permission(int sig, struct kernel_siginfo *info, - struct task_struct *t) -{ - struct pid *sid; - int error; - - if (!valid_signal(sig)) - return -EINVAL; - - if (!si_fromuser(info)) - return 0; - - error = audit_signal_info(sig, t); /* Let audit system see the signal */ - if (error) - return error; - - if (!same_thread_group(current, t) && - !kill_ok_by_cred(t)) - { - switch (sig) - { - case SIGCONT: - sid = task_session(t); - /* - * We don't return the error if sid == NULL. The - * task was unhashed, the caller must notice this. - */ - if (!sid || sid == task_session(current)) - break; - fallthrough; - default: - return -EPERM; - } - } - - return security_task_kill(t, info, sig, NULL); -} - -/** - * ptrace_trap_notify - schedule trap to notify ptracer - * @t: tracee wanting to notify tracer - * - * This function schedules sticky ptrace trap which is cleared on the next - * TRAP_STOP to notify ptracer of an event. @t must have been seized by - * ptracer. - * - * If @t is running, STOP trap will be taken. If trapped for STOP and - * ptracer is listening for events, tracee is woken up so that it can - * re-trap for the new event. If trapped otherwise, STOP trap will be - * eventually taken without returning to userland after the existing traps - * are finished by PTRACE_CONT. - * - * CONTEXT: - * Must be called with @task->sighand->siglock held. - */ -static void ptrace_trap_notify(struct task_struct *t) -{ - WARN_ON_ONCE(!(t->ptrace & PT_SEIZED)); - assert_spin_locked(&t->sighand->siglock); - - task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY); - ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING); -} - -/* - * Handle magic process-wide effects of stop/continue signals. Unlike - * the signal actions, these happen immediately at signal-generation - * time regardless of blocking, ignoring, or handling. This does the - * actual continuing for SIGCONT, but not the actual stopping for stop - * signals. The process stop is done as a signal action for SIG_DFL. - * - * Returns true if the signal should be actually delivered, otherwise - * it should be dropped. - */ -static bool prepare_signal(int sig, struct task_struct *p, bool force) -{ - struct signal_struct *signal = p->signal; - struct task_struct *t; - sigset_t flush; - - if (signal->flags & (SIGNAL_GROUP_EXIT | SIGNAL_GROUP_COREDUMP)) - { - if (!(signal->flags & SIGNAL_GROUP_EXIT)) - return sig == SIGKILL; - /* - * The process is in the middle of dying, nothing to do. - */ - } - else if (sig_kernel_stop(sig)) - { - /* - * This is a stop signal. Remove SIGCONT from all queues. - */ - siginitset(&flush, sigmask(SIGCONT)); - flush_sigqueue_mask(&flush, &signal->shared_pending); - for_each_thread(p, t) - flush_sigqueue_mask(&flush, &t->pending); - } - else if (sig == SIGCONT) - { - unsigned int why; - /* - * Remove all stop signals from all queues, wake all threads. - */ - siginitset(&flush, SIG_KERNEL_STOP_MASK); - flush_sigqueue_mask(&flush, &signal->shared_pending); - for_each_thread(p, t) - { - flush_sigqueue_mask(&flush, &t->pending); - task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING); - if (likely(!(t->ptrace & PT_SEIZED))) - wake_up_state(t, __TASK_STOPPED); - else - ptrace_trap_notify(t); - } - - /* - * Notify the parent with CLD_CONTINUED if we were stopped. - * - * If we were in the middle of a group stop, we pretend it - * was already finished, and then continued. Since SIGCHLD - * doesn't queue we report only CLD_STOPPED, as if the next - * CLD_CONTINUED was dropped. - */ - why = 0; - if (signal->flags & SIGNAL_STOP_STOPPED) - why |= SIGNAL_CLD_CONTINUED; - else if (signal->group_stop_count) - why |= SIGNAL_CLD_STOPPED; - - if (why) - { - /* - * The first thread which returns from do_signal_stop() - * will take ->siglock, notice SIGNAL_CLD_MASK, and - * notify its parent. See get_signal(). - */ - signal_set_stop_flags(signal, why | SIGNAL_STOP_CONTINUED); - signal->group_stop_count = 0; - signal->group_exit_code = 0; - } - } - - return !sig_ignored(p, sig, force); -} - -/* - * Test if P wants to take SIG. After we've checked all threads with this, - * it's equivalent to finding no threads not blocking SIG. Any threads not - * blocking SIG were ruled out because they are not running and already - * have pending signals. Such threads will dequeue from the shared queue - * as soon as they're available, so putting the signal on the shared queue - * will be equivalent to sending it to one such thread. - */ -static inline bool wants_signal(int sig, struct task_struct *p) -{ - if (sigismember(&p->blocked, sig)) - return false; - - if (p->flags & PF_EXITING) - return false; - - if (sig == SIGKILL) - return true; - - if (task_is_stopped_or_traced(p)) - return false; - - return task_curr(p) || !task_sigpending(p); -} - -static void complete_signal(int sig, struct task_struct *p, enum pid_type type) -{ - struct signal_struct *signal = p->signal; - struct task_struct *t; - - /* - * Now find a thread we can wake up to take the signal off the queue. - * - * If the main thread wants the signal, it gets first crack. - * Probably the least surprising to the average bear. - */ - if (wants_signal(sig, p)) - t = p; - else if ((type == PIDTYPE_PID) || thread_group_empty(p)) - /* - * There is just one thread and it does not need to be woken. - * It will dequeue unblocked signals before it runs again. - */ - return; - else - { - /* - * Otherwise try to find a suitable thread. - */ - t = signal->curr_target; - while (!wants_signal(sig, t)) - { - t = next_thread(t); - if (t == signal->curr_target) - /* - * No thread needs to be woken. - * Any eligible threads will see - * the signal in the queue soon. - */ - return; - } - signal->curr_target = t; - } - - /* - * Found a killable thread. If the signal will be fatal, - * then start taking the whole group down immediately. - */ - if (sig_fatal(p, sig) && - !(signal->flags & SIGNAL_GROUP_EXIT) && - !sigismember(&t->real_blocked, sig) && - (sig == SIGKILL || !p->ptrace)) - { - /* - * This signal will be fatal to the whole group. - */ - if (!sig_kernel_coredump(sig)) - { - /* - * Start a group exit and wake everybody up. - * This way we don't have other threads - * running and doing things after a slower - * thread has the fatal signal pending. - */ - signal->flags = SIGNAL_GROUP_EXIT; - signal->group_exit_code = sig; - signal->group_stop_count = 0; - t = p; - do - { - task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); - sigaddset(&t->pending.signal, SIGKILL); - signal_wake_up(t, 1); - } - while_each_thread(p, t); - return; - } - } - - /* - * The signal is already in the shared-pending queue. - * Tell the chosen thread to wake up and dequeue it. - */ - signal_wake_up(t, sig == SIGKILL); - return; -} - -static inline bool legacy_queue(struct sigpending *signals, int sig) -{ - return (sig < SIGRTMIN) && sigismember(&signals->signal, sig); -} - -static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struct *t, - enum pid_type type, bool force) -{ - struct sigpending *pending; - struct sigqueue *q; - int override_rlimit; - int ret = 0, result; - - assert_spin_locked(&t->sighand->siglock); - - result = TRACE_SIGNAL_IGNORED; - if (!prepare_signal(sig, t, force)) - goto ret; - - pending = (type != PIDTYPE_PID) ? &t->signal->shared_pending : &t->pending; - /* - * Short-circuit ignored signals and support queuing - * exactly one non-rt signal, so that we can get more - * detailed information about the cause of the signal. - */ - result = TRACE_SIGNAL_ALREADY_PENDING; - if (legacy_queue(pending, sig)) - goto ret; - - result = TRACE_SIGNAL_DELIVERED; - /* - * Skip useless siginfo allocation for SIGKILL and kernel threads. - */ - if ((sig == SIGKILL) || (t->flags & PF_KTHREAD)) - goto out_set; - - /* - * Real-time signals must be queued if sent by sigqueue, or - * some other real-time mechanism. It is implementation - * defined whether kill() does so. We attempt to do so, on - * the principle of least surprise, but since kill is not - * allowed to fail with EAGAIN when low on memory we just - * make sure at least one signal gets delivered and don't - * pass on the info struct. - */ - if (sig < SIGRTMIN) - override_rlimit = (is_si_special(info) || info->si_code >= 0); - else - override_rlimit = 0; - - q = __sigqueue_alloc(sig, t, GFP_ATOMIC, override_rlimit, 0); - - if (q) - { - list_add_tail(&q->list, &pending->list); - switch ((unsigned long)info) - { - case (unsigned long)SEND_SIG_NOINFO: - clear_siginfo(&q->info); - q->info.si_signo = sig; - q->info.si_errno = 0; - q->info.si_code = SI_USER; - q->info.si_pid = task_tgid_nr_ns(current, - task_active_pid_ns(t)); - rcu_read_lock(); - q->info.si_uid = - from_kuid_munged(task_cred_xxx(t, user_ns), - current_uid()); - rcu_read_unlock(); - break; - case (unsigned long)SEND_SIG_PRIV: - clear_siginfo(&q->info); - q->info.si_signo = sig; - q->info.si_errno = 0; - q->info.si_code = SI_KERNEL; - q->info.si_pid = 0; - q->info.si_uid = 0; - break; - default: - copy_siginfo(&q->info, info); - break; - } - } - else if (!is_si_special(info) && - sig >= SIGRTMIN && info->si_code != SI_USER) - { - /* - * Queue overflow, abort. We may abort if the - * signal was rt and sent by user using something - * other than kill(). - */ - result = TRACE_SIGNAL_OVERFLOW_FAIL; - ret = -EAGAIN; - goto ret; - } - else - { - /* - * This is a silent loss of information. We still - * send the signal, but the *info bits are lost. - */ - result = TRACE_SIGNAL_LOSE_INFO; - } - -out_set: - signalfd_notify(t, sig); - sigaddset(&pending->signal, sig); - - /* Let multiprocess signals appear after on-going forks */ - if (type > PIDTYPE_TGID) - { - struct multiprocess_signals *delayed; - hlist_for_each_entry(delayed, &t->signal->multiprocess, node) - { - sigset_t *signal = &delayed->signal; - /* Can't queue both a stop and a continue signal */ - if (sig == SIGCONT) - sigdelsetmask(signal, SIG_KERNEL_STOP_MASK); - else if (sig_kernel_stop(sig)) - sigdelset(signal, SIGCONT); - sigaddset(signal, sig); - } - } - - complete_signal(sig, t, type); -ret: - trace_signal_generate(sig, info, t, type != PIDTYPE_PID, result); - return ret; -} - -static inline bool has_si_pid_and_uid(struct kernel_siginfo *info) -{ - bool ret = false; - switch (siginfo_layout(info->si_signo, info->si_code)) - { - case SIL_KILL: - case SIL_CHLD: - case SIL_RT: - ret = true; - break; - case SIL_TIMER: - case SIL_POLL: - case SIL_FAULT: - case SIL_FAULT_TRAPNO: - case SIL_FAULT_MCEERR: - case SIL_FAULT_BNDERR: - case SIL_FAULT_PKUERR: - case SIL_FAULT_PERF_EVENT: - case SIL_SYS: - ret = false; - break; - } - return ret; -} - -static int send_signal(int sig, struct kernel_siginfo *info, struct task_struct *t, - enum pid_type type) -{ - /* Should SIGKILL or SIGSTOP be received by a pid namespace init? */ - bool force = false; - - if (info == SEND_SIG_NOINFO) - { - /* Force if sent from an ancestor pid namespace */ - force = !task_pid_nr_ns(current, task_active_pid_ns(t)); - } - else if (info == SEND_SIG_PRIV) - { - /* Don't ignore kernel generated signals */ - force = true; - } - else if (has_si_pid_and_uid(info)) - { - /* SIGKILL and SIGSTOP is special or has ids */ - struct user_namespace *t_user_ns; - - rcu_read_lock(); - t_user_ns = task_cred_xxx(t, user_ns); - if (current_user_ns() != t_user_ns) - { - kuid_t uid = make_kuid(current_user_ns(), info->si_uid); - info->si_uid = from_kuid_munged(t_user_ns, uid); - } - rcu_read_unlock(); - - /* A kernel generated signal? */ - force = (info->si_code == SI_KERNEL); - - /* From an ancestor pid namespace? */ - if (!task_pid_nr_ns(current, task_active_pid_ns(t))) - { - info->si_pid = 0; - force = true; - } - } - return __send_signal(sig, info, t, type, force); -} - -static void print_fatal_signal(int signr) -{ - struct pt_regs *regs = signal_pt_regs(); - pr_info("potentially unexpected fatal signal %d.\n", signr); - -#if defined(__i386__) && !defined(__arch_um__) - pr_info("code at %08lx: ", regs->ip); - { - int i; - for (i = 0; i < 16; i++) - { - unsigned char insn; - - if (get_user(insn, (unsigned char *)(regs->ip + i))) - break; - pr_cont("%02x ", insn); - } - } - pr_cont("\n"); -#endif - preempt_disable(); - show_regs(regs); - preempt_enable(); -} - -static int __init setup_print_fatal_signals(char *str) -{ - get_option(&str, &print_fatal_signals); - - return 1; -} - -__setup("print-fatal-signals=", setup_print_fatal_signals); - -int __group_send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p) -{ - return send_signal(sig, info, p, PIDTYPE_TGID); -} - -int do_send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p, - enum pid_type type) -{ - unsigned long flags; - int ret = -ESRCH; - - if (lock_task_sighand(p, &flags)) - { - ret = send_signal(sig, info, p, type); - unlock_task_sighand(p, &flags); - } - - return ret; -} - -/* - * Force a signal that the process can't ignore: if necessary - * we unblock the signal and change any SIG_IGN to SIG_DFL. - * - * Note: If we unblock the signal, we always reset it to SIG_DFL, - * since we do not want to have a signal handler that was blocked - * be invoked when user space had explicitly blocked it. - * - * We don't want to have recursive SIGSEGV's etc, for example, - * that is why we also clear SIGNAL_UNKILLABLE. - */ -static int -force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t, bool sigdfl) -{ - unsigned long int flags; - int ret, blocked, ignored; - struct k_sigaction *action; - int sig = info->si_signo; - - spin_lock_irqsave(&t->sighand->siglock, flags); - action = &t->sighand->action[sig - 1]; - ignored = action->sa.sa_handler == SIG_IGN; - blocked = sigismember(&t->blocked, sig); - if (blocked || ignored || sigdfl) - { - action->sa.sa_handler = SIG_DFL; - action->sa.sa_flags |= SA_IMMUTABLE; - if (blocked) - { - sigdelset(&t->blocked, sig); - recalc_sigpending_and_wake(t); - } - } - /* - * Don't clear SIGNAL_UNKILLABLE for traced tasks, users won't expect - * debugging to leave init killable. - */ - if (action->sa.sa_handler == SIG_DFL && !t->ptrace) - t->signal->flags &= ~SIGNAL_UNKILLABLE; - ret = send_signal(sig, info, t, PIDTYPE_PID); - spin_unlock_irqrestore(&t->sighand->siglock, flags); - - return ret; -} - -int force_sig_info(struct kernel_siginfo *info) -{ - return force_sig_info_to_task(info, current, false); -} - -/* - * Nuke all other threads in the group. - */ -int zap_other_threads(struct task_struct *p) -{ - struct task_struct *t = p; - int count = 0; - - p->signal->group_stop_count = 0; - - while_each_thread(p, t) - { - task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); - count++; - - /* Don't bother with already dead threads */ - if (t->exit_state) - continue; - sigaddset(&t->pending.signal, SIGKILL); - signal_wake_up(t, 1); - } - - return count; -} - -struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, - unsigned long *flags) -{ - struct sighand_struct *sighand; - - rcu_read_lock(); - for (;;) - { - sighand = rcu_dereference(tsk->sighand); - if (unlikely(sighand == NULL)) - break; - - /* - * This sighand can be already freed and even reused, but - * we rely on SLAB_TYPESAFE_BY_RCU and sighand_ctor() which - * initializes ->siglock: this slab can't go away, it has - * the same object type, ->siglock can't be reinitialized. - * - * We need to ensure that tsk->sighand is still the same - * after we take the lock, we can race with de_thread() or - * __exit_signal(). In the latter case the next iteration - * must see ->sighand == NULL. - */ - spin_lock_irqsave(&sighand->siglock, *flags); - if (likely(sighand == rcu_access_pointer(tsk->sighand))) - break; - spin_unlock_irqrestore(&sighand->siglock, *flags); - } - rcu_read_unlock(); - - return sighand; -} - -#ifdef CONFIG_LOCKDEP -void lockdep_assert_task_sighand_held(struct task_struct *task) -{ - struct sighand_struct *sighand; - - rcu_read_lock(); - sighand = rcu_dereference(task->sighand); - if (sighand) - lockdep_assert_held(&sighand->siglock); - else - WARN_ON_ONCE(1); - rcu_read_unlock(); -} -#endif - -/* - * send signal info to all the members of a group - */ -int group_send_sig_info(int sig, struct kernel_siginfo *info, - struct task_struct *p, enum pid_type type) -{ - int ret; - - rcu_read_lock(); - ret = check_kill_permission(sig, info, p); - rcu_read_unlock(); - - if (!ret && sig) - ret = do_send_sig_info(sig, info, p, type); - - return ret; -} - -/* - * __kill_pgrp_info() sends a signal to a process group: this is what the tty - * control characters do (^C, ^Z etc) - * - the caller must hold at least a readlock on tasklist_lock - */ -int __kill_pgrp_info(int sig, struct kernel_siginfo *info, struct pid *pgrp) -{ - struct task_struct *p = NULL; - int retval, success; - - success = 0; - retval = -ESRCH; - do_each_pid_task(pgrp, PIDTYPE_PGID, p) - { - int err = group_send_sig_info(sig, info, p, PIDTYPE_PGID); - success |= !err; - retval = err; - } - while_each_pid_task(pgrp, PIDTYPE_PGID, p); - return success ? 0 : retval; -} - -int kill_pid_info(int sig, struct kernel_siginfo *info, struct pid *pid) -{ - int error = -ESRCH; - struct task_struct *p; - - for (;;) - { - rcu_read_lock(); - p = pid_task(pid, PIDTYPE_PID); - if (p) - error = group_send_sig_info(sig, info, p, PIDTYPE_TGID); - rcu_read_unlock(); - if (likely(!p || error != -ESRCH)) - return error; - - /* - * The task was unhashed in between, try again. If it - * is dead, pid_task() will return NULL, if we race with - * de_thread() it will find the new leader. - */ - } -} - -static int kill_proc_info(int sig, struct kernel_siginfo *info, pid_t pid) -{ - int error; - rcu_read_lock(); - error = kill_pid_info(sig, info, find_vpid(pid)); - rcu_read_unlock(); - return error; -} - -static inline bool kill_as_cred_perm(const struct cred *cred, - struct task_struct *target) -{ - const struct cred *pcred = __task_cred(target); - - return uid_eq(cred->euid, pcred->suid) || - uid_eq(cred->euid, pcred->uid) || - uid_eq(cred->uid, pcred->suid) || - uid_eq(cred->uid, pcred->uid); -} - -/* - * The usb asyncio usage of siginfo is wrong. The glibc support - * for asyncio which uses SI_ASYNCIO assumes the layout is SIL_RT. - * AKA after the generic fields: - * kernel_pid_t si_pid; - * kernel_uid32_t si_uid; - * sigval_t si_value; - * - * Unfortunately when usb generates SI_ASYNCIO it assumes the layout - * after the generic fields is: - * void __user *si_addr; - * - * This is a practical problem when there is a 64bit big endian kernel - * and a 32bit userspace. As the 32bit address will encoded in the low - * 32bits of the pointer. Those low 32bits will be stored at higher - * address than appear in a 32 bit pointer. So userspace will not - * see the address it was expecting for it's completions. - * - * There is nothing in the encoding that can allow - * copy_siginfo_to_user32 to detect this confusion of formats, so - * handle this by requiring the caller of kill_pid_usb_asyncio to - * notice when this situration takes place and to store the 32bit - * pointer in sival_int, instead of sival_addr of the sigval_t addr - * parameter. - */ -int kill_pid_usb_asyncio(int sig, int errno, sigval_t addr, - struct pid *pid, const struct cred *cred) -{ - struct kernel_siginfo info; - struct task_struct *p; - unsigned long flags; - int ret = -EINVAL; - - if (!valid_signal(sig)) - return ret; - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = errno; - info.si_code = SI_ASYNCIO; - *((sigval_t *)&info.si_pid) = addr; - - rcu_read_lock(); - p = pid_task(pid, PIDTYPE_PID); - if (!p) - { - ret = -ESRCH; - goto out_unlock; - } - if (!kill_as_cred_perm(cred, p)) - { - ret = -EPERM; - goto out_unlock; - } - ret = security_task_kill(p, &info, sig, cred); - if (ret) - goto out_unlock; - - if (sig) - { - if (lock_task_sighand(p, &flags)) - { - ret = __send_signal(sig, &info, p, PIDTYPE_TGID, false); - unlock_task_sighand(p, &flags); - } - else - ret = -ESRCH; - } -out_unlock: - rcu_read_unlock(); - return ret; -} -EXPORT_SYMBOL_GPL(kill_pid_usb_asyncio); - -/* - * kill_something_info() interprets pid in interesting ways just like kill(2). - * - * POSIX specifies that kill(-1,sig) is unspecified, but what we have - * is probably wrong. Should make it like BSD or SYSV. - */ - -static int kill_something_info(int sig, struct kernel_siginfo *info, pid_t pid) -{ - int ret; - - if (pid > 0) - return kill_proc_info(sig, info, pid); - - /* -INT_MIN is undefined. Exclude this case to avoid a UBSAN warning */ - if (pid == INT_MIN) - return -ESRCH; - - read_lock(&tasklist_lock); - if (pid != -1) - { - ret = __kill_pgrp_info(sig, info, - pid ? find_vpid(-pid) : task_pgrp(current)); - } - else - { - int retval = 0, count = 0; - struct task_struct *p; - - for_each_process(p) - { - if (task_pid_vnr(p) > 1 && - !same_thread_group(p, current)) - { - int err = group_send_sig_info(sig, info, p, - PIDTYPE_MAX); - ++count; - if (err != -EPERM) - retval = err; - } - } - ret = count ? retval : -ESRCH; - } - read_unlock(&tasklist_lock); - - return ret; -} - -/* - * These are for backward compatibility with the rest of the kernel source. - */ - -int send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p) -{ - /* - * Make sure legacy kernel users don't send in bad values - * (normal paths check this in check_kill_permission). - */ - if (!valid_signal(sig)) - return -EINVAL; - - return do_send_sig_info(sig, info, p, PIDTYPE_PID); -} -EXPORT_SYMBOL(send_sig_info); - -#define __si_special(priv) \ - ((priv) ? SEND_SIG_PRIV : SEND_SIG_NOINFO) - -int send_sig(int sig, struct task_struct *p, int priv) -{ - return send_sig_info(sig, __si_special(priv), p); -} -EXPORT_SYMBOL(send_sig); - -void force_sig(int sig) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = 0; - info.si_code = SI_KERNEL; - info.si_pid = 0; - info.si_uid = 0; - force_sig_info(&info); -} -EXPORT_SYMBOL(force_sig); - -void force_fatal_sig(int sig) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = 0; - info.si_code = SI_KERNEL; - info.si_pid = 0; - info.si_uid = 0; - force_sig_info_to_task(&info, current, true); -} - -/* - * When things go south during signal handling, we - * will force a SIGSEGV. And if the signal that caused - * the problem was already a SIGSEGV, we'll want to - * make sure we don't even try to deliver the signal.. - */ -void force_sigsegv(int sig) -{ - if (sig == SIGSEGV) - force_fatal_sig(SIGSEGV); - else - force_sig(SIGSEGV); -} - -int force_sig_fault_to_task(int sig, int code, void __user *addr ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr), struct task_struct *t) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = 0; - info.si_code = code; - info.si_addr = addr; -#ifdef __ia64__ - info.si_imm = imm; - info.si_flags = flags; - info.si_isr = isr; -#endif - return force_sig_info_to_task(&info, t, false); -} - -int force_sig_fault(int sig, int code, void __user *addr ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)) -{ - return force_sig_fault_to_task(sig, code, addr ___ARCH_SI_IA64(imm, flags, isr), current); -} - -int send_sig_fault(int sig, int code, void __user *addr ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr), struct task_struct *t) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = 0; - info.si_code = code; - info.si_addr = addr; -#ifdef __ia64__ - info.si_imm = imm; - info.si_flags = flags; - info.si_isr = isr; -#endif - return send_sig_info(info.si_signo, &info, t); -} - -int force_sig_mceerr(int code, void __user *addr, short lsb) -{ - struct kernel_siginfo info; - - WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR)); - clear_siginfo(&info); - info.si_signo = SIGBUS; - info.si_errno = 0; - info.si_code = code; - info.si_addr = addr; - info.si_addr_lsb = lsb; - return force_sig_info(&info); -} - -int send_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t) -{ - struct kernel_siginfo info; - - WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR)); - clear_siginfo(&info); - info.si_signo = SIGBUS; - info.si_errno = 0; - info.si_code = code; - info.si_addr = addr; - info.si_addr_lsb = lsb; - return send_sig_info(info.si_signo, &info, t); -} -EXPORT_SYMBOL(send_sig_mceerr); - -int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = SIGSEGV; - info.si_errno = 0; - info.si_code = SEGV_BNDERR; - info.si_addr = addr; - info.si_lower = lower; - info.si_upper = upper; - return force_sig_info(&info); -} - -#ifdef SEGV_PKUERR -int force_sig_pkuerr(void __user *addr, u32 pkey) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = SIGSEGV; - info.si_errno = 0; - info.si_code = SEGV_PKUERR; - info.si_addr = addr; - info.si_pkey = pkey; - return force_sig_info(&info); -} -#endif - -int force_sig_perf(void __user *addr, u32 type, u64 sig_data) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = SIGTRAP; - info.si_errno = 0; - info.si_code = TRAP_PERF; - info.si_addr = addr; - info.si_perf_data = sig_data; - info.si_perf_type = type; - - return force_sig_info(&info); -} - -/** - * force_sig_seccomp - signals the task to allow in-process syscall emulation - * @syscall: syscall number to send to userland - * @reason: filter-supplied reason code to send to userland (via si_errno) - * - * Forces a SIGSYS with a code of SYS_SECCOMP and related sigsys info. - */ -int force_sig_seccomp(int syscall, int reason, bool force_coredump) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = SIGSYS; - info.si_code = SYS_SECCOMP; - info.si_call_addr = (void __user *)KSTK_EIP(current); - info.si_errno = reason; - info.si_arch = syscall_get_arch(current); - info.si_syscall = syscall; - return force_sig_info_to_task(&info, current, force_coredump); -} - -/* For the crazy architectures that include trap information in - * the errno field, instead of an actual errno value. - */ -int force_sig_ptrace_errno_trap(int errno, void __user *addr) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = SIGTRAP; - info.si_errno = errno; - info.si_code = TRAP_HWBKPT; - info.si_addr = addr; - return force_sig_info(&info); -} - -/* For the rare architectures that include trap information using - * si_trapno. - */ -int force_sig_fault_trapno(int sig, int code, void __user *addr, int trapno) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = 0; - info.si_code = code; - info.si_addr = addr; - info.si_trapno = trapno; - return force_sig_info(&info); -} - -/* For the rare architectures that include trap information using - * si_trapno. - */ -int send_sig_fault_trapno(int sig, int code, void __user *addr, int trapno, - struct task_struct *t) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = 0; - info.si_code = code; - info.si_addr = addr; - info.si_trapno = trapno; - return send_sig_info(info.si_signo, &info, t); -} - -int kill_pgrp(struct pid *pid, int sig, int priv) -{ - int ret; - - read_lock(&tasklist_lock); - ret = __kill_pgrp_info(sig, __si_special(priv), pid); - read_unlock(&tasklist_lock); - - return ret; -} -EXPORT_SYMBOL(kill_pgrp); - -int kill_pid(struct pid *pid, int sig, int priv) -{ - return kill_pid_info(sig, __si_special(priv), pid); -} -EXPORT_SYMBOL(kill_pid); - -/* - * These functions support sending signals using preallocated sigqueue - * structures. This is needed "because realtime applications cannot - * afford to lose notifications of asynchronous events, like timer - * expirations or I/O completions". In the case of POSIX Timers - * we allocate the sigqueue structure from the timer_create. If this - * allocation fails we are able to report the failure to the application - * with an EAGAIN error. - */ -struct sigqueue *sigqueue_alloc(void) -{ - return __sigqueue_alloc(-1, current, GFP_KERNEL, 0, SIGQUEUE_PREALLOC); -} - -void sigqueue_free(struct sigqueue *q) -{ - unsigned long flags; - spinlock_t *lock = ¤t->sighand->siglock; - - BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); - /* - * We must hold ->siglock while testing q->list - * to serialize with collect_signal() or with - * __exit_signal()->flush_sigqueue(). - */ - spin_lock_irqsave(lock, flags); - q->flags &= ~SIGQUEUE_PREALLOC; - /* - * If it is queued it will be freed when dequeued, - * like the "regular" sigqueue. - */ - if (!list_empty(&q->list)) - q = NULL; - spin_unlock_irqrestore(lock, flags); - - if (q) - __sigqueue_free(q); -} - -int send_sigqueue(struct sigqueue *q, struct pid *pid, enum pid_type type) -{ - int sig = q->info.si_signo; - struct sigpending *pending; - struct task_struct *t; - unsigned long flags; - int ret, result; - - BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); - - ret = -1; - rcu_read_lock(); - t = pid_task(pid, type); - if (!t || !likely(lock_task_sighand(t, &flags))) - goto ret; - - ret = 1; /* the signal is ignored */ - result = TRACE_SIGNAL_IGNORED; - if (!prepare_signal(sig, t, false)) - goto out; - - ret = 0; - if (unlikely(!list_empty(&q->list))) - { - /* - * If an SI_TIMER entry is already queue just increment - * the overrun count. - */ - BUG_ON(q->info.si_code != SI_TIMER); - q->info.si_overrun++; - result = TRACE_SIGNAL_ALREADY_PENDING; - goto out; - } - q->info.si_overrun = 0; - - signalfd_notify(t, sig); - pending = (type != PIDTYPE_PID) ? &t->signal->shared_pending : &t->pending; - list_add_tail(&q->list, &pending->list); - sigaddset(&pending->signal, sig); - complete_signal(sig, t, type); - result = TRACE_SIGNAL_DELIVERED; -out: - trace_signal_generate(sig, &q->info, t, type != PIDTYPE_PID, result); - unlock_task_sighand(t, &flags); -ret: - rcu_read_unlock(); - return ret; -} - -static void do_notify_pidfd(struct task_struct *task) -{ - struct pid *pid; - - WARN_ON(task->exit_state == 0); - pid = task_pid(task); - wake_up_all(&pid->wait_pidfd); -} - -/* - * Let a parent know about the death of a child. - * For a stopped/continued status change, use do_notify_parent_cldstop instead. - * - * Returns true if our parent ignored us and so we've switched to - * self-reaping. - */ -bool do_notify_parent(struct task_struct *tsk, int sig) -{ - struct kernel_siginfo info; - unsigned long flags; - struct sighand_struct *psig; - bool autoreap = false; - u64 utime, stime; - - BUG_ON(sig == -1); - - /* do_notify_parent_cldstop should have been called instead. */ - BUG_ON(task_is_stopped_or_traced(tsk)); - - BUG_ON(!tsk->ptrace && - (tsk->group_leader != tsk || !thread_group_empty(tsk))); - - /* Wake up all pidfd waiters */ - do_notify_pidfd(tsk); - - if (sig != SIGCHLD) - { - /* - * This is only possible if parent == real_parent. - * Check if it has changed security domain. - */ - if (tsk->parent_exec_id != READ_ONCE(tsk->parent->self_exec_id)) - sig = SIGCHLD; - } - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = 0; - /* - * We are under tasklist_lock here so our parent is tied to - * us and cannot change. - * - * task_active_pid_ns will always return the same pid namespace - * until a task passes through release_task. - * - * write_lock() currently calls preempt_disable() which is the - * same as rcu_read_lock(), but according to Oleg, this is not - * correct to rely on this - */ - rcu_read_lock(); - info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(tsk->parent)); - info.si_uid = from_kuid_munged(task_cred_xxx(tsk->parent, user_ns), - task_uid(tsk)); - rcu_read_unlock(); - - task_cputime(tsk, &utime, &stime); - info.si_utime = nsec_to_clock_t(utime + tsk->signal->utime); - info.si_stime = nsec_to_clock_t(stime + tsk->signal->stime); - - info.si_status = tsk->exit_code & 0x7f; - if (tsk->exit_code & 0x80) - info.si_code = CLD_DUMPED; - else if (tsk->exit_code & 0x7f) - info.si_code = CLD_KILLED; - else - { - info.si_code = CLD_EXITED; - info.si_status = tsk->exit_code >> 8; - } - - psig = tsk->parent->sighand; - spin_lock_irqsave(&psig->siglock, flags); - if (!tsk->ptrace && sig == SIGCHLD && - (psig->action[SIGCHLD - 1].sa.sa_handler == SIG_IGN || - (psig->action[SIGCHLD - 1].sa.sa_flags & SA_NOCLDWAIT))) - { - /* - * We are exiting and our parent doesn't care. POSIX.1 - * defines special semantics for setting SIGCHLD to SIG_IGN - * or setting the SA_NOCLDWAIT flag: we should be reaped - * automatically and not left for our parent's wait4 call. - * Rather than having the parent do it as a magic kind of - * signal handler, we just set this to tell do_exit that we - * can be cleaned up without becoming a zombie. Note that - * we still call __wake_up_parent in this case, because a - * blocked sys_wait4 might now return -ECHILD. - * - * Whether we send SIGCHLD or not for SA_NOCLDWAIT - * is implementation-defined: we do (if you don't want - * it, just use SIG_IGN instead). - */ - autoreap = true; - if (psig->action[SIGCHLD - 1].sa.sa_handler == SIG_IGN) - sig = 0; - } - /* - * Send with __send_signal as si_pid and si_uid are in the - * parent's namespaces. - */ - if (valid_signal(sig) && sig) - __send_signal(sig, &info, tsk->parent, PIDTYPE_TGID, false); - __wake_up_parent(tsk, tsk->parent); - spin_unlock_irqrestore(&psig->siglock, flags); - - return autoreap; -} - -/** - * do_notify_parent_cldstop - notify parent of stopped/continued state change - * @tsk: task reporting the state change - * @for_ptracer: the notification is for ptracer - * @why: CLD_{CONTINUED|STOPPED|TRAPPED} to report - * - * Notify @tsk's parent that the stopped/continued state has changed. If - * @for_ptracer is %false, @tsk's group leader notifies to its real parent. - * If %true, @tsk reports to @tsk->parent which should be the ptracer. - * - * CONTEXT: - * Must be called with tasklist_lock at least read locked. - */ -static void do_notify_parent_cldstop(struct task_struct *tsk, - bool for_ptracer, int why) -{ - struct kernel_siginfo info; - unsigned long flags; - struct task_struct *parent; - struct sighand_struct *sighand; - u64 utime, stime; - - if (for_ptracer) - { - parent = tsk->parent; - } - else - { - tsk = tsk->group_leader; - parent = tsk->real_parent; - } - - clear_siginfo(&info); - info.si_signo = SIGCHLD; - info.si_errno = 0; - /* - * see comment in do_notify_parent() about the following 4 lines - */ - rcu_read_lock(); - info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(parent)); - info.si_uid = from_kuid_munged(task_cred_xxx(parent, user_ns), task_uid(tsk)); - rcu_read_unlock(); - - task_cputime(tsk, &utime, &stime); - info.si_utime = nsec_to_clock_t(utime); - info.si_stime = nsec_to_clock_t(stime); - - info.si_code = why; - switch (why) - { - case CLD_CONTINUED: - info.si_status = SIGCONT; - break; - case CLD_STOPPED: - info.si_status = tsk->signal->group_exit_code & 0x7f; - break; - case CLD_TRAPPED: - info.si_status = tsk->exit_code & 0x7f; - break; - default: - BUG(); - } - - sighand = parent->sighand; - spin_lock_irqsave(&sighand->siglock, flags); - if (sighand->action[SIGCHLD - 1].sa.sa_handler != SIG_IGN && - !(sighand->action[SIGCHLD - 1].sa.sa_flags & SA_NOCLDSTOP)) - __group_send_sig_info(SIGCHLD, &info, parent); - /* - * Even if SIGCHLD is not generated, we must wake up wait4 calls. - */ - __wake_up_parent(tsk, parent); - spin_unlock_irqrestore(&sighand->siglock, flags); -} - -/* - * This must be called with current->sighand->siglock held. - * - * This should be the path for all ptrace stops. - * We always set current->last_siginfo while stopped here. - * That makes it a way to test a stopped process for - * being ptrace-stopped vs being job-control-stopped. - * - * If we actually decide not to stop at all because the tracer - * is gone, we keep current->exit_code unless clear_code. - */ -static void ptrace_stop(int exit_code, int why, int clear_code, kernel_siginfo_t *info) - __releases(¤t->sighand->siglock) - __acquires(¤t->sighand->siglock) -{ - bool gstop_done = false; - - if (arch_ptrace_stop_needed()) - { - /* - * The arch code has something special to do before a - * ptrace stop. This is allowed to block, e.g. for faults - * on user stack pages. We can't keep the siglock while - * calling arch_ptrace_stop, so we must release it now. - * To preserve proper semantics, we must do this before - * any signal bookkeeping like checking group_stop_count. - */ - spin_unlock_irq(¤t->sighand->siglock); - arch_ptrace_stop(); - spin_lock_irq(¤t->sighand->siglock); - } - - /* - * schedule() will not sleep if there is a pending signal that - * can awaken the task. - */ - set_special_state(TASK_TRACED); - - /* - * We're committing to trapping. TRACED should be visible before - * TRAPPING is cleared; otherwise, the tracer might fail do_wait(). - * Also, transition to TRACED and updates to ->jobctl should be - * atomic with respect to siglock and should be done after the arch - * hook as siglock is released and regrabbed across it. - * - * TRACER TRACEE - * - * ptrace_attach() - * [L] wait_on_bit(JOBCTL_TRAPPING) [S] set_special_state(TRACED) - * do_wait() - * set_current_state() smp_wmb(); - * ptrace_do_wait() - * wait_task_stopped() - * task_stopped_code() - * [L] task_is_traced() [S] task_clear_jobctl_trapping(); - */ - smp_wmb(); - - current->last_siginfo = info; - current->exit_code = exit_code; - - /* - * If @why is CLD_STOPPED, we're trapping to participate in a group - * stop. Do the bookkeeping. Note that if SIGCONT was delievered - * across siglock relocks since INTERRUPT was scheduled, PENDING - * could be clear now. We act as if SIGCONT is received after - * TASK_TRACED is entered - ignore it. - */ - if (why == CLD_STOPPED && (current->jobctl & JOBCTL_STOP_PENDING)) - gstop_done = task_participate_group_stop(current); - - /* any trap clears pending STOP trap, STOP trap clears NOTIFY */ - task_clear_jobctl_pending(current, JOBCTL_TRAP_STOP); - if (info && info->si_code >> 8 == PTRACE_EVENT_STOP) - task_clear_jobctl_pending(current, JOBCTL_TRAP_NOTIFY); - - /* entering a trap, clear TRAPPING */ - task_clear_jobctl_trapping(current); - - spin_unlock_irq(¤t->sighand->siglock); - read_lock(&tasklist_lock); - if (likely(current->ptrace)) - { - /* - * Notify parents of the stop. - * - * While ptraced, there are two parents - the ptracer and - * the real_parent of the group_leader. The ptracer should - * know about every stop while the real parent is only - * interested in the completion of group stop. The states - * for the two don't interact with each other. Notify - * separately unless they're gonna be duplicates. - */ - do_notify_parent_cldstop(current, true, why); - if (gstop_done && ptrace_reparented(current)) - do_notify_parent_cldstop(current, false, why); - - /* - * Don't want to allow preemption here, because - * sys_ptrace() needs this task to be inactive. - * - * XXX: implement read_unlock_no_resched(). - */ - preempt_disable(); - read_unlock(&tasklist_lock); - cgroup_enter_frozen(); - preempt_enable_no_resched(); - freezable_schedule(); - cgroup_leave_frozen(true); - } - else - { - /* - * By the time we got the lock, our tracer went away. - * Don't drop the lock yet, another tracer may come. - * - * If @gstop_done, the ptracer went away between group stop - * completion and here. During detach, it would have set - * JOBCTL_STOP_PENDING on us and we'll re-enter - * TASK_STOPPED in do_signal_stop() on return, so notifying - * the real parent of the group stop completion is enough. - */ - if (gstop_done) - do_notify_parent_cldstop(current, false, why); - - /* tasklist protects us from ptrace_freeze_traced() */ - __set_current_state(TASK_RUNNING); - if (clear_code) - current->exit_code = 0; - read_unlock(&tasklist_lock); - } - - /* - * We are back. Now reacquire the siglock before touching - * last_siginfo, so that we are sure to have synchronized with - * any signal-sending on another CPU that wants to examine it. - */ - spin_lock_irq(¤t->sighand->siglock); - current->last_siginfo = NULL; - - /* LISTENING can be set only during STOP traps, clear it */ - current->jobctl &= ~JOBCTL_LISTENING; - - /* - * Queued signals ignored us while we were stopped for tracing. - * So check for any that we should take before resuming user mode. - * This sets TIF_SIGPENDING, but never clears it. - */ - recalc_sigpending_tsk(current); -} - -static void ptrace_do_notify(int signr, int exit_code, int why) -{ - kernel_siginfo_t info; - - clear_siginfo(&info); - info.si_signo = signr; - info.si_code = exit_code; - info.si_pid = task_pid_vnr(current); - info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); - - /* Let the debugger run. */ - ptrace_stop(exit_code, why, 1, &info); -} - -void ptrace_notify(int exit_code) -{ - BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP); - if (unlikely(current->task_works)) - task_work_run(); - - spin_lock_irq(¤t->sighand->siglock); - ptrace_do_notify(SIGTRAP, exit_code, CLD_TRAPPED); - spin_unlock_irq(¤t->sighand->siglock); -} - -/** - * do_signal_stop - handle group stop for SIGSTOP and other stop signals - * @signr: signr causing group stop if initiating - * - * If %JOBCTL_STOP_PENDING is not set yet, initiate group stop with @signr - * and participate in it. If already set, participate in the existing - * group stop. If participated in a group stop (and thus slept), %true is - * returned with siglock released. - * - * If ptraced, this function doesn't handle stop itself. Instead, - * %JOBCTL_TRAP_STOP is scheduled and %false is returned with siglock - * untouched. The caller must ensure that INTERRUPT trap handling takes - * places afterwards. - * - * CONTEXT: - * Must be called with @current->sighand->siglock held, which is released - * on %true return. - * - * RETURNS: - * %false if group stop is already cancelled or ptrace trap is scheduled. - * %true if participated in group stop. - */ -static bool do_signal_stop(int signr) - __releases(¤t->sighand->siglock) -{ - struct signal_struct *sig = current->signal; - - if (!(current->jobctl & JOBCTL_STOP_PENDING)) - { - unsigned long gstop = JOBCTL_STOP_PENDING | JOBCTL_STOP_CONSUME; - struct task_struct *t; - - /* signr will be recorded in task->jobctl for retries */ - WARN_ON_ONCE(signr & ~JOBCTL_STOP_SIGMASK); - - if (!likely(current->jobctl & JOBCTL_STOP_DEQUEUED) || - unlikely(signal_group_exit(sig))) - return false; - /* - * There is no group stop already in progress. We must - * initiate one now. - * - * While ptraced, a task may be resumed while group stop is - * still in effect and then receive a stop signal and - * initiate another group stop. This deviates from the - * usual behavior as two consecutive stop signals can't - * cause two group stops when !ptraced. That is why we - * also check !task_is_stopped(t) below. - * - * The condition can be distinguished by testing whether - * SIGNAL_STOP_STOPPED is already set. Don't generate - * group_exit_code in such case. - * - * This is not necessary for SIGNAL_STOP_CONTINUED because - * an intervening stop signal is required to cause two - * continued events regardless of ptrace. - */ - if (!(sig->flags & SIGNAL_STOP_STOPPED)) - sig->group_exit_code = signr; - - sig->group_stop_count = 0; - - if (task_set_jobctl_pending(current, signr | gstop)) - sig->group_stop_count++; - - t = current; - while_each_thread(current, t) - { - /* - * Setting state to TASK_STOPPED for a group - * stop is always done with the siglock held, - * so this check has no races. - */ - if (!task_is_stopped(t) && - task_set_jobctl_pending(t, signr | gstop)) - { - sig->group_stop_count++; - if (likely(!(t->ptrace & PT_SEIZED))) - signal_wake_up(t, 0); - else - ptrace_trap_notify(t); - } - } - } - - if (likely(!current->ptrace)) - { - int notify = 0; - - /* - * If there are no other threads in the group, or if there - * is a group stop in progress and we are the last to stop, - * report to the parent. - */ - if (task_participate_group_stop(current)) - notify = CLD_STOPPED; - - set_special_state(TASK_STOPPED); - spin_unlock_irq(¤t->sighand->siglock); - - /* - * Notify the parent of the group stop completion. Because - * we're not holding either the siglock or tasklist_lock - * here, ptracer may attach inbetween; however, this is for - * group stop and should always be delivered to the real - * parent of the group leader. The new ptracer will get - * its notification when this task transitions into - * TASK_TRACED. - */ - if (notify) - { - read_lock(&tasklist_lock); - do_notify_parent_cldstop(current, false, notify); - read_unlock(&tasklist_lock); - } - - /* Now we don't run again until woken by SIGCONT or SIGKILL */ - cgroup_enter_frozen(); - freezable_schedule(); - return true; - } - else - { - /* - * While ptraced, group stop is handled by STOP trap. - * Schedule it and let the caller deal with it. - */ - task_set_jobctl_pending(current, JOBCTL_TRAP_STOP); - return false; - } -} - -/** - * do_jobctl_trap - take care of ptrace jobctl traps - * - * When PT_SEIZED, it's used for both group stop and explicit - * SEIZE/INTERRUPT traps. Both generate PTRACE_EVENT_STOP trap with - * accompanying siginfo. If stopped, lower eight bits of exit_code contain - * the stop signal; otherwise, %SIGTRAP. - * - * When !PT_SEIZED, it's used only for group stop trap with stop signal - * number as exit_code and no siginfo. - * - * CONTEXT: - * Must be called with @current->sighand->siglock held, which may be - * released and re-acquired before returning with intervening sleep. - */ -static void do_jobctl_trap(void) -{ - struct signal_struct *signal = current->signal; - int signr = current->jobctl & JOBCTL_STOP_SIGMASK; - - if (current->ptrace & PT_SEIZED) - { - if (!signal->group_stop_count && - !(signal->flags & SIGNAL_STOP_STOPPED)) - signr = SIGTRAP; - WARN_ON_ONCE(!signr); - ptrace_do_notify(signr, signr | (PTRACE_EVENT_STOP << 8), - CLD_STOPPED); - } - else - { - WARN_ON_ONCE(!signr); - ptrace_stop(signr, CLD_STOPPED, 0, NULL); - current->exit_code = 0; - } -} - -/** - * do_freezer_trap - handle the freezer jobctl trap - * - * Puts the task into frozen state, if only the task is not about to quit. - * In this case it drops JOBCTL_TRAP_FREEZE. - * - * CONTEXT: - * Must be called with @current->sighand->siglock held, - * which is always released before returning. - */ -static void do_freezer_trap(void) - __releases(¤t->sighand->siglock) -{ - /* - * If there are other trap bits pending except JOBCTL_TRAP_FREEZE, - * let's make another loop to give it a chance to be handled. - * In any case, we'll return back. - */ - if ((current->jobctl & (JOBCTL_PENDING_MASK | JOBCTL_TRAP_FREEZE)) != - JOBCTL_TRAP_FREEZE) - { - spin_unlock_irq(¤t->sighand->siglock); - return; - } - - /* - * Now we're sure that there is no pending fatal signal and no - * pending traps. Clear TIF_SIGPENDING to not get out of schedule() - * immediately (if there is a non-fatal signal pending), and - * put the task into sleep. - */ - __set_current_state(TASK_INTERRUPTIBLE); - clear_thread_flag(TIF_SIGPENDING); - spin_unlock_irq(¤t->sighand->siglock); - cgroup_enter_frozen(); - freezable_schedule(); -} - -static int ptrace_signal(int signr, kernel_siginfo_t *info) -{ - /* - * We do not check sig_kernel_stop(signr) but set this marker - * unconditionally because we do not know whether debugger will - * change signr. This flag has no meaning unless we are going - * to stop after return from ptrace_stop(). In this case it will - * be checked in do_signal_stop(), we should only stop if it was - * not cleared by SIGCONT while we were sleeping. See also the - * comment in dequeue_signal(). - */ - current->jobctl |= JOBCTL_STOP_DEQUEUED; - ptrace_stop(signr, CLD_TRAPPED, 0, info); - - /* We're back. Did the debugger cancel the sig? */ - signr = current->exit_code; - if (signr == 0) - return signr; - - current->exit_code = 0; - - /* - * Update the siginfo structure if the signal has - * changed. If the debugger wanted something - * specific in the siginfo structure then it should - * have updated *info via PTRACE_SETSIGINFO. - */ - if (signr != info->si_signo) - { - clear_siginfo(info); - info->si_signo = signr; - info->si_errno = 0; - info->si_code = SI_USER; - rcu_read_lock(); - info->si_pid = task_pid_vnr(current->parent); - info->si_uid = from_kuid_munged(current_user_ns(), - task_uid(current->parent)); - rcu_read_unlock(); - } - - /* If the (new) signal is now blocked, requeue it. */ - if (sigismember(¤t->blocked, signr)) - { - send_signal(signr, info, current, PIDTYPE_PID); - signr = 0; - } - - return signr; -} - -static void hide_si_addr_tag_bits(struct ksignal *ksig) -{ - switch (siginfo_layout(ksig->sig, ksig->info.si_code)) - { - case SIL_FAULT: - case SIL_FAULT_TRAPNO: - case SIL_FAULT_MCEERR: - case SIL_FAULT_BNDERR: - case SIL_FAULT_PKUERR: - case SIL_FAULT_PERF_EVENT: - ksig->info.si_addr = arch_untagged_si_addr( - ksig->info.si_addr, ksig->sig, ksig->info.si_code); - break; - case SIL_KILL: - case SIL_TIMER: - case SIL_POLL: - case SIL_CHLD: - case SIL_RT: - case SIL_SYS: - break; - } -} - -bool get_signal(struct ksignal *ksig) -{ - struct sighand_struct *sighand = current->sighand; - struct signal_struct *signal = current->signal; - int signr; - - if (unlikely(current->task_works)) - task_work_run(); - - /* - * For non-generic architectures, check for TIF_NOTIFY_SIGNAL so - * that the arch handlers don't all have to do it. If we get here - * without TIF_SIGPENDING, just exit after running signal work. - */ - if (!IS_ENABLED(CONFIG_GENERIC_ENTRY)) - { - if (test_thread_flag(TIF_NOTIFY_SIGNAL)) - tracehook_notify_signal(); - if (!task_sigpending(current)) - return false; - } - - if (unlikely(uprobe_deny_signal())) - return false; - - /* - * Do this once, we can't return to user-mode if freezing() == T. - * do_signal_stop() and ptrace_stop() do freezable_schedule() and - * thus do not need another check after return. - */ - try_to_freeze(); - -relock: - spin_lock_irq(&sighand->siglock); - - /* - * Every stopped thread goes here after wakeup. Check to see if - * we should notify the parent, prepare_signal(SIGCONT) encodes - * the CLD_ si_code into SIGNAL_CLD_MASK bits. - */ - if (unlikely(signal->flags & SIGNAL_CLD_MASK)) - { - int why; - - if (signal->flags & SIGNAL_CLD_CONTINUED) - why = CLD_CONTINUED; - else - why = CLD_STOPPED; - - signal->flags &= ~SIGNAL_CLD_MASK; - - spin_unlock_irq(&sighand->siglock); - - /* - * Notify the parent that we're continuing. This event is - * always per-process and doesn't make whole lot of sense - * for ptracers, who shouldn't consume the state via - * wait(2) either, but, for backward compatibility, notify - * the ptracer of the group leader too unless it's gonna be - * a duplicate. - */ - read_lock(&tasklist_lock); - do_notify_parent_cldstop(current, false, why); - - if (ptrace_reparented(current->group_leader)) - do_notify_parent_cldstop(current->group_leader, - true, why); - read_unlock(&tasklist_lock); - - goto relock; - } - - /* Has this task already been marked for death? */ - if (signal_group_exit(signal)) - { - ksig->info.si_signo = signr = SIGKILL; - sigdelset(¤t->pending.signal, SIGKILL); - trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, - &sighand->action[SIGKILL - 1]); - recalc_sigpending(); - goto fatal; - } - - for (;;) - { - struct k_sigaction *ka; - - if (unlikely(current->jobctl & JOBCTL_STOP_PENDING) && - do_signal_stop(0)) - goto relock; - - if (unlikely(current->jobctl & - (JOBCTL_TRAP_MASK | JOBCTL_TRAP_FREEZE))) - { - if (current->jobctl & JOBCTL_TRAP_MASK) - { - do_jobctl_trap(); - spin_unlock_irq(&sighand->siglock); - } - else if (current->jobctl & JOBCTL_TRAP_FREEZE) - do_freezer_trap(); - - goto relock; - } - - /* - * If the task is leaving the frozen state, let's update - * cgroup counters and reset the frozen bit. - */ - if (unlikely(cgroup_task_frozen(current))) - { - spin_unlock_irq(&sighand->siglock); - cgroup_leave_frozen(false); - goto relock; - } - - /* - * Signals generated by the execution of an instruction - * need to be delivered before any other pending signals - * so that the instruction pointer in the signal stack - * frame points to the faulting instruction. - */ - signr = dequeue_synchronous_signal(&ksig->info); - if (!signr) - signr = dequeue_signal(current, ¤t->blocked, &ksig->info); - - if (!signr) - break; /* will return 0 */ - - if (unlikely(current->ptrace) && (signr != SIGKILL) && - !(sighand->action[signr - 1].sa.sa_flags & SA_IMMUTABLE)) - { - signr = ptrace_signal(signr, &ksig->info); - if (!signr) - continue; - } - - ka = &sighand->action[signr - 1]; - - /* Trace actually delivered signals. */ - trace_signal_deliver(signr, &ksig->info, ka); - - if (ka->sa.sa_handler == SIG_IGN) /* Do nothing. */ - continue; - if (ka->sa.sa_handler != SIG_DFL) - { - /* Run the handler. */ - ksig->ka = *ka; - - if (ka->sa.sa_flags & SA_ONESHOT) - ka->sa.sa_handler = SIG_DFL; - - break; /* will return non-zero "signr" value */ - } - - /* - * Now we are doing the default action for this signal. - */ - if (sig_kernel_ignore(signr)) /* Default is nothing. */ - continue; - - /* - * Global init gets no signals it doesn't want. - * Container-init gets no signals it doesn't want from same - * container. - * - * Note that if global/container-init sees a sig_kernel_only() - * signal here, the signal must have been generated internally - * or must have come from an ancestor namespace. In either - * case, the signal cannot be dropped. - */ - if (unlikely(signal->flags & SIGNAL_UNKILLABLE) && - !sig_kernel_only(signr)) - continue; - - if (sig_kernel_stop(signr)) - { - /* - * The default action is to stop all threads in - * the thread group. The job control signals - * do nothing in an orphaned pgrp, but SIGSTOP - * always works. Note that siglock needs to be - * dropped during the call to is_orphaned_pgrp() - * because of lock ordering with tasklist_lock. - * This allows an intervening SIGCONT to be posted. - * We need to check for that and bail out if necessary. - */ - if (signr != SIGSTOP) - { - spin_unlock_irq(&sighand->siglock); - - /* signals can be posted during this window */ - - if (is_current_pgrp_orphaned()) - goto relock; - - spin_lock_irq(&sighand->siglock); - } - - if (likely(do_signal_stop(ksig->info.si_signo))) - { - /* It released the siglock. */ - goto relock; - } - - /* - * We didn't actually stop, due to a race - * with SIGCONT or something like that. - */ - continue; - } - - fatal: - spin_unlock_irq(&sighand->siglock); - if (unlikely(cgroup_task_frozen(current))) - cgroup_leave_frozen(true); - - /* - * Anything else is fatal, maybe with a core dump. - */ - current->flags |= PF_SIGNALED; - - if (sig_kernel_coredump(signr)) - { - if (print_fatal_signals) - print_fatal_signal(ksig->info.si_signo); - proc_coredump_connector(current); - /* - * If it was able to dump core, this kills all - * other threads in the group and synchronizes with - * their demise. If we lost the race with another - * thread getting here, it set group_exit_code - * first and our do_group_exit call below will use - * that value and ignore the one we pass it. - */ - do_coredump(&ksig->info); - } - - /* - * PF_IO_WORKER threads will catch and exit on fatal signals - * themselves. They have cleanup that must be performed, so - * we cannot call do_exit() on their behalf. - */ - if (current->flags & PF_IO_WORKER) - goto out; - - /* - * Death signals, no core dump. - */ - do_group_exit(ksig->info.si_signo); - /* NOTREACHED */ - } - spin_unlock_irq(&sighand->siglock); -out: - ksig->sig = signr; - - if (!(ksig->ka.sa.sa_flags & SA_EXPOSE_TAGBITS)) - hide_si_addr_tag_bits(ksig); - - return ksig->sig > 0; -} - -/** - * signal_delivered - - * @ksig: kernel signal struct - * @stepping: nonzero if debugger single-step or block-step in use - * - * This function should be called when a signal has successfully been - * delivered. It updates the blocked signals accordingly (@ksig->ka.sa.sa_mask - * is always blocked, and the signal itself is blocked unless %SA_NODEFER - * is set in @ksig->ka.sa.sa_flags. Tracing is notified. - */ -static void signal_delivered(struct ksignal *ksig, int stepping) -{ - sigset_t blocked; - - /* A signal was successfully delivered, and the - saved sigmask was stored on the signal frame, - and will be restored by sigreturn. So we can - simply clear the restore sigmask flag. */ - clear_restore_sigmask(); - - sigorsets(&blocked, ¤t->blocked, &ksig->ka.sa.sa_mask); - if (!(ksig->ka.sa.sa_flags & SA_NODEFER)) - sigaddset(&blocked, ksig->sig); - set_current_blocked(&blocked); - if (current->sas_ss_flags & SS_AUTODISARM) - sas_ss_reset(current); - tracehook_signal_handler(stepping); -} - -void signal_setup_done(int failed, struct ksignal *ksig, int stepping) -{ - if (failed) - force_sigsegv(ksig->sig); - else - signal_delivered(ksig, stepping); -} - -/* - * It could be that complete_signal() picked us to notify about the - * group-wide signal. Other threads should be notified now to take - * the shared signals in @which since we will not. - */ -static void retarget_shared_pending(struct task_struct *tsk, sigset_t *which) -{ - sigset_t retarget; - struct task_struct *t; - - sigandsets(&retarget, &tsk->signal->shared_pending.signal, which); - if (sigisemptyset(&retarget)) - return; - - t = tsk; - while_each_thread(tsk, t) - { - if (t->flags & PF_EXITING) - continue; - - if (!has_pending_signals(&retarget, &t->blocked)) - continue; - /* Remove the signals this thread can handle. */ - sigandsets(&retarget, &retarget, &t->blocked); - - if (!task_sigpending(t)) - signal_wake_up(t, 0); - - if (sigisemptyset(&retarget)) - break; - } -} - -void exit_signals(struct task_struct *tsk) -{ - int group_stop = 0; - sigset_t unblocked; - - /* - * @tsk is about to have PF_EXITING set - lock out users which - * expect stable threadgroup. - */ - cgroup_threadgroup_change_begin(tsk); - - if (thread_group_empty(tsk) || signal_group_exit(tsk->signal)) - { - tsk->flags |= PF_EXITING; - cgroup_threadgroup_change_end(tsk); - return; - } - - spin_lock_irq(&tsk->sighand->siglock); - /* - * From now this task is not visible for group-wide signals, - * see wants_signal(), do_signal_stop(). - */ - tsk->flags |= PF_EXITING; - - cgroup_threadgroup_change_end(tsk); - - if (!task_sigpending(tsk)) - goto out; - - unblocked = tsk->blocked; - signotset(&unblocked); - retarget_shared_pending(tsk, &unblocked); - - if (unlikely(tsk->jobctl & JOBCTL_STOP_PENDING) && - task_participate_group_stop(tsk)) - group_stop = CLD_STOPPED; -out: - spin_unlock_irq(&tsk->sighand->siglock); - - /* - * If group stop has completed, deliver the notification. This - * should always go to the real parent of the group leader. - */ - if (unlikely(group_stop)) - { - read_lock(&tasklist_lock); - do_notify_parent_cldstop(tsk, false, group_stop); - read_unlock(&tasklist_lock); - } -} - -/* - * System call entry points. - */ - -/** - * sys_restart_syscall - restart a system call - */ -SYSCALL_DEFINE0(restart_syscall) -{ - struct restart_block *restart = ¤t->restart_block; - return restart->fn(restart); -} - -long do_no_restart_syscall(struct restart_block *param) -{ - return -EINTR; -} - -static void __set_task_blocked(struct task_struct *tsk, const sigset_t *newset) -{ - if (task_sigpending(tsk) && !thread_group_empty(tsk)) - { - sigset_t newblocked; - /* A set of now blocked but previously unblocked signals. */ - sigandnsets(&newblocked, newset, ¤t->blocked); - retarget_shared_pending(tsk, &newblocked); - } - tsk->blocked = *newset; - recalc_sigpending(); -} - -/** - * set_current_blocked - change current->blocked mask - * @newset: new mask - * - * It is wrong to change ->blocked directly, this helper should be used - * to ensure the process can't miss a shared signal we are going to block. - */ -void set_current_blocked(sigset_t *newset) -{ - sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP)); - __set_current_blocked(newset); -} - -void __set_current_blocked(const sigset_t *newset) -{ - struct task_struct *tsk = current; - - /* - * In case the signal mask hasn't changed, there is nothing we need - * to do. The current->blocked shouldn't be modified by other task. - */ - if (sigequalsets(&tsk->blocked, newset)) - return; - - spin_lock_irq(&tsk->sighand->siglock); - __set_task_blocked(tsk, newset); - spin_unlock_irq(&tsk->sighand->siglock); -} - -/* - * This is also useful for kernel threads that want to temporarily - * (or permanently) block certain signals. - * - * NOTE! Unlike the user-mode sys_sigprocmask(), the kernel - * interface happily blocks "unblockable" signals like SIGKILL - * and friends. - */ -int sigprocmask(int how, sigset_t *set, sigset_t *oldset) -{ - struct task_struct *tsk = current; - sigset_t newset; - - /* Lockless, only current can change ->blocked, never from irq */ - if (oldset) - *oldset = tsk->blocked; - - switch (how) - { - case SIG_BLOCK: - sigorsets(&newset, &tsk->blocked, set); - break; - case SIG_UNBLOCK: - sigandnsets(&newset, &tsk->blocked, set); - break; - case SIG_SETMASK: - newset = *set; - break; - default: - return -EINVAL; - } - - __set_current_blocked(&newset); - return 0; -} -EXPORT_SYMBOL(sigprocmask); - -/* - * The api helps set app-provided sigmasks. - * - * This is useful for syscalls such as ppoll, pselect, io_pgetevents and - * epoll_pwait where a new sigmask is passed from userland for the syscalls. - * - * Note that it does set_restore_sigmask() in advance, so it must be always - * paired with restore_saved_sigmask_unless() before return from syscall. - */ -int set_user_sigmask(const sigset_t __user *umask, size_t sigsetsize) -{ - sigset_t kmask; - - if (!umask) - return 0; - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - if (copy_from_user(&kmask, umask, sizeof(sigset_t))) - return -EFAULT; - - set_restore_sigmask(); - current->saved_sigmask = current->blocked; - set_current_blocked(&kmask); - - return 0; -} - -#ifdef CONFIG_COMPAT -int set_compat_user_sigmask(const compat_sigset_t __user *umask, - size_t sigsetsize) -{ - sigset_t kmask; - - if (!umask) - return 0; - if (sigsetsize != sizeof(compat_sigset_t)) - return -EINVAL; - if (get_compat_sigset(&kmask, umask)) - return -EFAULT; - - set_restore_sigmask(); - current->saved_sigmask = current->blocked; - set_current_blocked(&kmask); - - return 0; -} -#endif - -/** - * sys_rt_sigprocmask - change the list of currently blocked signals - * @how: whether to add, remove, or set signals - * @nset: stores pending signals - * @oset: previous value of signal mask if non-null - * @sigsetsize: size of sigset_t type - */ -SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, nset, - sigset_t __user *, oset, size_t, sigsetsize) -{ - sigset_t old_set, new_set; - int error; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - old_set = current->blocked; - - if (nset) - { - if (copy_from_user(&new_set, nset, sizeof(sigset_t))) - return -EFAULT; - sigdelsetmask(&new_set, sigmask(SIGKILL) | sigmask(SIGSTOP)); - - error = sigprocmask(how, &new_set, NULL); - if (error) - return error; - } - - if (oset) - { - if (copy_to_user(oset, &old_set, sizeof(sigset_t))) - return -EFAULT; - } - - return 0; -} - -#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, - compat_sigset_t __user *, oset, compat_size_t, sigsetsize) -{ - sigset_t old_set = current->blocked; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (nset) - { - sigset_t new_set; - int error; - if (get_compat_sigset(&new_set, nset)) - return -EFAULT; - sigdelsetmask(&new_set, sigmask(SIGKILL) | sigmask(SIGSTOP)); - - error = sigprocmask(how, &new_set, NULL); - if (error) - return error; - } - return oset ? put_compat_sigset(oset, &old_set, sizeof(*oset)) : 0; -} -#endif - -static void do_sigpending(sigset_t *set) -{ - spin_lock_irq(¤t->sighand->siglock); - sigorsets(set, ¤t->pending.signal, - ¤t->signal->shared_pending.signal); - spin_unlock_irq(¤t->sighand->siglock); - - /* Outside the lock because only this thread touches it. */ - sigandsets(set, ¤t->blocked, set); -} - -/** - * sys_rt_sigpending - examine a pending signal that has been raised - * while blocked - * @uset: stores pending signals - * @sigsetsize: size of sigset_t type or larger - */ -SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize) -{ - sigset_t set; - - if (sigsetsize > sizeof(*uset)) - return -EINVAL; - - do_sigpending(&set); - - if (copy_to_user(uset, &set, sigsetsize)) - return -EFAULT; - - return 0; -} - -#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset, - compat_size_t, sigsetsize) -{ - sigset_t set; - - if (sigsetsize > sizeof(*uset)) - return -EINVAL; - - do_sigpending(&set); - - return put_compat_sigset(uset, &set, sigsetsize); -} -#endif - -static const struct -{ - unsigned char limit, layout; -} sig_sicodes[] = { - [SIGILL] = {NSIGILL, SIL_FAULT}, - [SIGFPE] = {NSIGFPE, SIL_FAULT}, - [SIGSEGV] = {NSIGSEGV, SIL_FAULT}, - [SIGBUS] = {NSIGBUS, SIL_FAULT}, - [SIGTRAP] = {NSIGTRAP, SIL_FAULT}, -#if defined(SIGEMT) - [SIGEMT] = {NSIGEMT, SIL_FAULT}, -#endif - [SIGCHLD] = {NSIGCHLD, SIL_CHLD}, - [SIGPOLL] = {NSIGPOLL, SIL_POLL}, - [SIGSYS] = {NSIGSYS, SIL_SYS}, -}; - -static bool known_siginfo_layout(unsigned sig, int si_code) -{ - if (si_code == SI_KERNEL) - return true; - else if ((si_code > SI_USER)) - { - if (sig_specific_sicodes(sig)) - { - if (si_code <= sig_sicodes[sig].limit) - return true; - } - else if (si_code <= NSIGPOLL) - return true; - } - else if (si_code >= SI_DETHREAD) - return true; - else if (si_code == SI_ASYNCNL) - return true; - return false; -} - -enum siginfo_layout siginfo_layout(unsigned sig, int si_code) -{ - enum siginfo_layout layout = SIL_KILL; - if ((si_code > SI_USER) && (si_code < SI_KERNEL)) - { - if ((sig < ARRAY_SIZE(sig_sicodes)) && - (si_code <= sig_sicodes[sig].limit)) - { - layout = sig_sicodes[sig].layout; - /* Handle the exceptions */ - if ((sig == SIGBUS) && - (si_code >= BUS_MCEERR_AR) && (si_code <= BUS_MCEERR_AO)) - layout = SIL_FAULT_MCEERR; - else if ((sig == SIGSEGV) && (si_code == SEGV_BNDERR)) - layout = SIL_FAULT_BNDERR; -#ifdef SEGV_PKUERR - else if ((sig == SIGSEGV) && (si_code == SEGV_PKUERR)) - layout = SIL_FAULT_PKUERR; -#endif - else if ((sig == SIGTRAP) && (si_code == TRAP_PERF)) - layout = SIL_FAULT_PERF_EVENT; - else if (IS_ENABLED(CONFIG_SPARC) && - (sig == SIGILL) && (si_code == ILL_ILLTRP)) - layout = SIL_FAULT_TRAPNO; - else if (IS_ENABLED(CONFIG_ALPHA) && - ((sig == SIGFPE) || - ((sig == SIGTRAP) && (si_code == TRAP_UNK)))) - layout = SIL_FAULT_TRAPNO; - } - else if (si_code <= NSIGPOLL) - layout = SIL_POLL; - } - else - { - if (si_code == SI_TIMER) - layout = SIL_TIMER; - else if (si_code == SI_SIGIO) - layout = SIL_POLL; - else if (si_code < 0) - layout = SIL_RT; - } - return layout; -} - -static inline char __user *si_expansion(const siginfo_t __user *info) -{ - return ((char __user *)info) + sizeof(struct kernel_siginfo); -} - -int copy_siginfo_to_user(siginfo_t __user *to, const kernel_siginfo_t *from) -{ - char __user *expansion = si_expansion(to); - if (copy_to_user(to, from, sizeof(struct kernel_siginfo))) - return -EFAULT; - if (clear_user(expansion, SI_EXPANSION_SIZE)) - return -EFAULT; - return 0; -} - -static int post_copy_siginfo_from_user(kernel_siginfo_t *info, - const siginfo_t __user *from) -{ - if (unlikely(!known_siginfo_layout(info->si_signo, info->si_code))) - { - char __user *expansion = si_expansion(from); - char buf[SI_EXPANSION_SIZE]; - int i; - /* - * An unknown si_code might need more than - * sizeof(struct kernel_siginfo) bytes. Verify all of the - * extra bytes are 0. This guarantees copy_siginfo_to_user - * will return this data to userspace exactly. - */ - if (copy_from_user(&buf, expansion, SI_EXPANSION_SIZE)) - return -EFAULT; - for (i = 0; i < SI_EXPANSION_SIZE; i++) - { - if (buf[i] != 0) - return -E2BIG; - } - } - return 0; -} - -static int __copy_siginfo_from_user(int signo, kernel_siginfo_t *to, - const siginfo_t __user *from) -{ - if (copy_from_user(to, from, sizeof(struct kernel_siginfo))) - return -EFAULT; - to->si_signo = signo; - return post_copy_siginfo_from_user(to, from); -} - -int copy_siginfo_from_user(kernel_siginfo_t *to, const siginfo_t __user *from) -{ - if (copy_from_user(to, from, sizeof(struct kernel_siginfo))) - return -EFAULT; - return post_copy_siginfo_from_user(to, from); -} - -#ifdef CONFIG_COMPAT -/** - * copy_siginfo_to_external32 - copy a kernel siginfo into a compat user siginfo - * @to: compat siginfo destination - * @from: kernel siginfo source - * - * Note: This function does not work properly for the SIGCHLD on x32, but - * fortunately it doesn't have to. The only valid callers for this function are - * copy_siginfo_to_user32, which is overriden for x32 and the coredump code. - * The latter does not care because SIGCHLD will never cause a coredump. - */ -void copy_siginfo_to_external32(struct compat_siginfo *to, - const struct kernel_siginfo *from) -{ - memset(to, 0, sizeof(*to)); - - to->si_signo = from->si_signo; - to->si_errno = from->si_errno; - to->si_code = from->si_code; - switch (siginfo_layout(from->si_signo, from->si_code)) - { - case SIL_KILL: - to->si_pid = from->si_pid; - to->si_uid = from->si_uid; - break; - case SIL_TIMER: - to->si_tid = from->si_tid; - to->si_overrun = from->si_overrun; - to->si_int = from->si_int; - break; - case SIL_POLL: - to->si_band = from->si_band; - to->si_fd = from->si_fd; - break; - case SIL_FAULT: - to->si_addr = ptr_to_compat(from->si_addr); - break; - case SIL_FAULT_TRAPNO: - to->si_addr = ptr_to_compat(from->si_addr); - to->si_trapno = from->si_trapno; - break; - case SIL_FAULT_MCEERR: - to->si_addr = ptr_to_compat(from->si_addr); - to->si_addr_lsb = from->si_addr_lsb; - break; - case SIL_FAULT_BNDERR: - to->si_addr = ptr_to_compat(from->si_addr); - to->si_lower = ptr_to_compat(from->si_lower); - to->si_upper = ptr_to_compat(from->si_upper); - break; - case SIL_FAULT_PKUERR: - to->si_addr = ptr_to_compat(from->si_addr); - to->si_pkey = from->si_pkey; - break; - case SIL_FAULT_PERF_EVENT: - to->si_addr = ptr_to_compat(from->si_addr); - to->si_perf_data = from->si_perf_data; - to->si_perf_type = from->si_perf_type; - break; - case SIL_CHLD: - to->si_pid = from->si_pid; - to->si_uid = from->si_uid; - to->si_status = from->si_status; - to->si_utime = from->si_utime; - to->si_stime = from->si_stime; - break; - case SIL_RT: - to->si_pid = from->si_pid; - to->si_uid = from->si_uid; - to->si_int = from->si_int; - break; - case SIL_SYS: - to->si_call_addr = ptr_to_compat(from->si_call_addr); - to->si_syscall = from->si_syscall; - to->si_arch = from->si_arch; - break; - } -} - -int __copy_siginfo_to_user32(struct compat_siginfo __user *to, - const struct kernel_siginfo *from) -{ - struct compat_siginfo new; - - copy_siginfo_to_external32(&new, from); - if (copy_to_user(to, &new, sizeof(struct compat_siginfo))) - return -EFAULT; - return 0; -} - -static int post_copy_siginfo_from_user32(kernel_siginfo_t *to, - const struct compat_siginfo *from) -{ - clear_siginfo(to); - to->si_signo = from->si_signo; - to->si_errno = from->si_errno; - to->si_code = from->si_code; - switch (siginfo_layout(from->si_signo, from->si_code)) - { - case SIL_KILL: - to->si_pid = from->si_pid; - to->si_uid = from->si_uid; - break; - case SIL_TIMER: - to->si_tid = from->si_tid; - to->si_overrun = from->si_overrun; - to->si_int = from->si_int; - break; - case SIL_POLL: - to->si_band = from->si_band; - to->si_fd = from->si_fd; - break; - case SIL_FAULT: - to->si_addr = compat_ptr(from->si_addr); - break; - case SIL_FAULT_TRAPNO: - to->si_addr = compat_ptr(from->si_addr); - to->si_trapno = from->si_trapno; - break; - case SIL_FAULT_MCEERR: - to->si_addr = compat_ptr(from->si_addr); - to->si_addr_lsb = from->si_addr_lsb; - break; - case SIL_FAULT_BNDERR: - to->si_addr = compat_ptr(from->si_addr); - to->si_lower = compat_ptr(from->si_lower); - to->si_upper = compat_ptr(from->si_upper); - break; - case SIL_FAULT_PKUERR: - to->si_addr = compat_ptr(from->si_addr); - to->si_pkey = from->si_pkey; - break; - case SIL_FAULT_PERF_EVENT: - to->si_addr = compat_ptr(from->si_addr); - to->si_perf_data = from->si_perf_data; - to->si_perf_type = from->si_perf_type; - break; - case SIL_CHLD: - to->si_pid = from->si_pid; - to->si_uid = from->si_uid; - to->si_status = from->si_status; -#ifdef CONFIG_X86_X32_ABI - if (in_x32_syscall()) - { - to->si_utime = from->_sifields._sigchld_x32._utime; - to->si_stime = from->_sifields._sigchld_x32._stime; - } - else -#endif - { - to->si_utime = from->si_utime; - to->si_stime = from->si_stime; - } - break; - case SIL_RT: - to->si_pid = from->si_pid; - to->si_uid = from->si_uid; - to->si_int = from->si_int; - break; - case SIL_SYS: - to->si_call_addr = compat_ptr(from->si_call_addr); - to->si_syscall = from->si_syscall; - to->si_arch = from->si_arch; - break; - } - return 0; -} - -static int __copy_siginfo_from_user32(int signo, struct kernel_siginfo *to, - const struct compat_siginfo __user *ufrom) -{ - struct compat_siginfo from; - - if (copy_from_user(&from, ufrom, sizeof(struct compat_siginfo))) - return -EFAULT; - - from.si_signo = signo; - return post_copy_siginfo_from_user32(to, &from); -} - -int copy_siginfo_from_user32(struct kernel_siginfo *to, - const struct compat_siginfo __user *ufrom) -{ - struct compat_siginfo from; - - if (copy_from_user(&from, ufrom, sizeof(struct compat_siginfo))) - return -EFAULT; - - return post_copy_siginfo_from_user32(to, &from); -} -#endif /* CONFIG_COMPAT */ - -/** - * do_sigtimedwait - wait for queued signals specified in @which - * @which: queued signals to wait for - * @info: if non-null, the signal's siginfo is returned here - * @ts: upper bound on process time suspension - */ -static int do_sigtimedwait(const sigset_t *which, kernel_siginfo_t *info, - const struct timespec64 *ts) -{ - ktime_t *to = NULL, timeout = KTIME_MAX; - struct task_struct *tsk = current; - sigset_t mask = *which; - int sig, ret = 0; - - if (ts) - { - if (!timespec64_valid(ts)) - return -EINVAL; - timeout = timespec64_to_ktime(*ts); - to = &timeout; - } - - /* - * Invert the set of allowed signals to get those we want to block. - */ - sigdelsetmask(&mask, sigmask(SIGKILL) | sigmask(SIGSTOP)); - signotset(&mask); - - spin_lock_irq(&tsk->sighand->siglock); - sig = dequeue_signal(tsk, &mask, info); - if (!sig && timeout) - { - /* - * None ready, temporarily unblock those we're interested - * while we are sleeping in so that we'll be awakened when - * they arrive. Unblocking is always fine, we can avoid - * set_current_blocked(). - */ - tsk->real_blocked = tsk->blocked; - sigandsets(&tsk->blocked, &tsk->blocked, &mask); - recalc_sigpending(); - spin_unlock_irq(&tsk->sighand->siglock); - - __set_current_state(TASK_INTERRUPTIBLE); - ret = freezable_schedule_hrtimeout_range(to, tsk->timer_slack_ns, - HRTIMER_MODE_REL); - spin_lock_irq(&tsk->sighand->siglock); - __set_task_blocked(tsk, &tsk->real_blocked); - sigemptyset(&tsk->real_blocked); - sig = dequeue_signal(tsk, &mask, info); - } - spin_unlock_irq(&tsk->sighand->siglock); - - if (sig) - return sig; - return ret ? -EINTR : -EAGAIN; -} - -/** - * sys_rt_sigtimedwait - synchronously wait for queued signals specified - * in @uthese - * @uthese: queued signals to wait for - * @uinfo: if non-null, the signal's siginfo is returned here - * @uts: upper bound on process time suspension - * @sigsetsize: size of sigset_t type - */ -SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese, - siginfo_t __user *, uinfo, - const struct __kernel_timespec __user *, uts, - size_t, sigsetsize) -{ - sigset_t these; - struct timespec64 ts; - kernel_siginfo_t info; - int ret; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (copy_from_user(&these, uthese, sizeof(these))) - return -EFAULT; - - if (uts) - { - if (get_timespec64(&ts, uts)) - return -EFAULT; - } - - ret = do_sigtimedwait(&these, &info, uts ? &ts : NULL); - - if (ret > 0 && uinfo) - { - if (copy_siginfo_to_user(uinfo, &info)) - ret = -EFAULT; - } - - return ret; -} - -#ifdef CONFIG_COMPAT_32BIT_TIME -SYSCALL_DEFINE4(rt_sigtimedwait_time32, const sigset_t __user *, uthese, - siginfo_t __user *, uinfo, - const struct old_timespec32 __user *, uts, - size_t, sigsetsize) -{ - sigset_t these; - struct timespec64 ts; - kernel_siginfo_t info; - int ret; - - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (copy_from_user(&these, uthese, sizeof(these))) - return -EFAULT; - - if (uts) - { - if (get_old_timespec32(&ts, uts)) - return -EFAULT; - } - - ret = do_sigtimedwait(&these, &info, uts ? &ts : NULL); - - if (ret > 0 && uinfo) - { - if (copy_siginfo_to_user(uinfo, &info)) - ret = -EFAULT; - } - - return ret; -} -#endif - -#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait_time64, compat_sigset_t __user *, uthese, - struct compat_siginfo __user *, uinfo, - struct __kernel_timespec __user *, uts, compat_size_t, sigsetsize) -{ - sigset_t s; - struct timespec64 t; - kernel_siginfo_t info; - long ret; - - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (get_compat_sigset(&s, uthese)) - return -EFAULT; - - if (uts) - { - if (get_timespec64(&t, uts)) - return -EFAULT; - } - - ret = do_sigtimedwait(&s, &info, uts ? &t : NULL); - - if (ret > 0 && uinfo) - { - if (copy_siginfo_to_user32(uinfo, &info)) - ret = -EFAULT; - } - - return ret; -} - -#ifdef CONFIG_COMPAT_32BIT_TIME -COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait_time32, compat_sigset_t __user *, uthese, - struct compat_siginfo __user *, uinfo, - struct old_timespec32 __user *, uts, compat_size_t, sigsetsize) -{ - sigset_t s; - struct timespec64 t; - kernel_siginfo_t info; - long ret; - - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (get_compat_sigset(&s, uthese)) - return -EFAULT; - - if (uts) - { - if (get_old_timespec32(&t, uts)) - return -EFAULT; - } - - ret = do_sigtimedwait(&s, &info, uts ? &t : NULL); - - if (ret > 0 && uinfo) - { - if (copy_siginfo_to_user32(uinfo, &info)) - ret = -EFAULT; - } - - return ret; -} -#endif -#endif - -static inline void prepare_kill_siginfo(int sig, struct kernel_siginfo *info) -{ - clear_siginfo(info); - info->si_signo = sig; - info->si_errno = 0; - info->si_code = SI_USER; - info->si_pid = task_tgid_vnr(current); - info->si_uid = from_kuid_munged(current_user_ns(), current_uid()); -} - -/** - * sys_kill - send a signal to a process - * @pid: the PID of the process - * @sig: signal to be sent - */ -SYSCALL_DEFINE2(kill, pid_t, pid, int, sig) -{ - struct kernel_siginfo info; - - prepare_kill_siginfo(sig, &info); - - return kill_something_info(sig, &info, pid); -} - -/* - * Verify that the signaler and signalee either are in the same pid namespace - * or that the signaler's pid namespace is an ancestor of the signalee's pid - * namespace. - */ -static bool access_pidfd_pidns(struct pid *pid) -{ - struct pid_namespace *active = task_active_pid_ns(current); - struct pid_namespace *p = ns_of_pid(pid); - - for (;;) - { - if (!p) - return false; - if (p == active) - break; - p = p->parent; - } - - return true; -} - -static int copy_siginfo_from_user_any(kernel_siginfo_t *kinfo, - siginfo_t __user *info) -{ -#ifdef CONFIG_COMPAT - /* - * Avoid hooking up compat syscalls and instead handle necessary - * conversions here. Note, this is a stop-gap measure and should not be - * considered a generic solution. - */ - if (in_compat_syscall()) - return copy_siginfo_from_user32( - kinfo, (struct compat_siginfo __user *)info); -#endif - return copy_siginfo_from_user(kinfo, info); -} - -static struct pid *pidfd_to_pid(const struct file *file) -{ - struct pid *pid; - - pid = pidfd_pid(file); - if (!IS_ERR(pid)) - return pid; - - return tgid_pidfd_to_pid(file); -} - -/** - * sys_pidfd_send_signal - Signal a process through a pidfd - * @pidfd: file descriptor of the process - * @sig: signal to send - * @info: signal info - * @flags: future flags - * - * The syscall currently only signals via PIDTYPE_PID which covers - * kill(, . It does not signal threads or process - * groups. - * In order to extend the syscall to threads and process groups the @flags - * argument should be used. In essence, the @flags argument will determine - * what is signaled and not the file descriptor itself. Put in other words, - * grouping is a property of the flags argument not a property of the file - * descriptor. - * - * Return: 0 on success, negative errno on failure - */ -SYSCALL_DEFINE4(pidfd_send_signal, int, pidfd, int, sig, - siginfo_t __user *, info, unsigned int, flags) -{ - int ret; - struct fd f; - struct pid *pid; - kernel_siginfo_t kinfo; - - /* Enforce flags be set to 0 until we add an extension. */ - if (flags) - return -EINVAL; - - f = fdget(pidfd); - if (!f.file) - return -EBADF; - - /* Is this a pidfd? */ - pid = pidfd_to_pid(f.file); - if (IS_ERR(pid)) - { - ret = PTR_ERR(pid); - goto err; - } - - ret = -EINVAL; - if (!access_pidfd_pidns(pid)) - goto err; - - if (info) - { - ret = copy_siginfo_from_user_any(&kinfo, info); - if (unlikely(ret)) - goto err; - - ret = -EINVAL; - if (unlikely(sig != kinfo.si_signo)) - goto err; - - /* Only allow sending arbitrary signals to yourself. */ - ret = -EPERM; - if ((task_pid(current) != pid) && - (kinfo.si_code >= 0 || kinfo.si_code == SI_TKILL)) - goto err; - } - else - { - prepare_kill_siginfo(sig, &kinfo); - } - - ret = kill_pid_info(sig, &kinfo, pid); - -err: - fdput(f); - return ret; -} - -static int -do_send_specific(pid_t tgid, pid_t pid, int sig, struct kernel_siginfo *info) -{ - struct task_struct *p; - int error = -ESRCH; - - rcu_read_lock(); - p = find_task_by_vpid(pid); - if (p && (tgid <= 0 || task_tgid_vnr(p) == tgid)) - { - error = check_kill_permission(sig, info, p); - /* - * The null signal is a permissions and process existence - * probe. No signal is actually delivered. - */ - if (!error && sig) - { - error = do_send_sig_info(sig, info, p, PIDTYPE_PID); - /* - * If lock_task_sighand() failed we pretend the task - * dies after receiving the signal. The window is tiny, - * and the signal is private anyway. - */ - if (unlikely(error == -ESRCH)) - error = 0; - } - } - rcu_read_unlock(); - - return error; -} - -static int do_tkill(pid_t tgid, pid_t pid, int sig) -{ - struct kernel_siginfo info; - - clear_siginfo(&info); - info.si_signo = sig; - info.si_errno = 0; - info.si_code = SI_TKILL; - info.si_pid = task_tgid_vnr(current); - info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); - - return do_send_specific(tgid, pid, sig, &info); -} - -/** - * sys_tgkill - send signal to one specific thread - * @tgid: the thread group ID of the thread - * @pid: the PID of the thread - * @sig: signal to be sent - * - * This syscall also checks the @tgid and returns -ESRCH even if the PID - * exists but it's not belonging to the target process anymore. This - * method solves the problem of threads exiting and PIDs getting reused. - */ -SYSCALL_DEFINE3(tgkill, pid_t, tgid, pid_t, pid, int, sig) -{ - /* This is only valid for single tasks */ - if (pid <= 0 || tgid <= 0) - return -EINVAL; - - return do_tkill(tgid, pid, sig); -} - -/** - * sys_tkill - send signal to one specific task - * @pid: the PID of the task - * @sig: signal to be sent - * - * Send a signal to only one task, even if it's a CLONE_THREAD task. - */ -SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig) -{ - /* This is only valid for single tasks */ - if (pid <= 0) - return -EINVAL; - - return do_tkill(0, pid, sig); -} - -static int do_rt_sigqueueinfo(pid_t pid, int sig, kernel_siginfo_t *info) -{ - /* Not even root can pretend to send signals from the kernel. - * Nor can they impersonate a kill()/tgkill(), which adds source info. - */ - if ((info->si_code >= 0 || info->si_code == SI_TKILL) && - (task_pid_vnr(current) != pid)) - return -EPERM; - - /* POSIX.1b doesn't mention process groups. */ - return kill_proc_info(sig, info, pid); -} - -/** - * sys_rt_sigqueueinfo - send signal information to a signal - * @pid: the PID of the thread - * @sig: signal to be sent - * @uinfo: signal info to be sent - */ -SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig, - siginfo_t __user *, uinfo) -{ - kernel_siginfo_t info; - int ret = __copy_siginfo_from_user(sig, &info, uinfo); - if (unlikely(ret)) - return ret; - return do_rt_sigqueueinfo(pid, sig, &info); -} - -#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo, - compat_pid_t, pid, - int, sig, - struct compat_siginfo __user *, uinfo) -{ - kernel_siginfo_t info; - int ret = __copy_siginfo_from_user32(sig, &info, uinfo); - if (unlikely(ret)) - return ret; - return do_rt_sigqueueinfo(pid, sig, &info); -} -#endif - -static int do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, kernel_siginfo_t *info) -{ - /* This is only valid for single tasks */ - if (pid <= 0 || tgid <= 0) - return -EINVAL; - - /* Not even root can pretend to send signals from the kernel. - * Nor can they impersonate a kill()/tgkill(), which adds source info. - */ - if ((info->si_code >= 0 || info->si_code == SI_TKILL) && - (task_pid_vnr(current) != pid)) - return -EPERM; - - return do_send_specific(tgid, pid, sig, info); -} - -SYSCALL_DEFINE4(rt_tgsigqueueinfo, pid_t, tgid, pid_t, pid, int, sig, - siginfo_t __user *, uinfo) -{ - kernel_siginfo_t info; - int ret = __copy_siginfo_from_user(sig, &info, uinfo); - if (unlikely(ret)) - return ret; - return do_rt_tgsigqueueinfo(tgid, pid, sig, &info); -} - -#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo, - compat_pid_t, tgid, - compat_pid_t, pid, - int, sig, - struct compat_siginfo __user *, uinfo) -{ - kernel_siginfo_t info; - int ret = __copy_siginfo_from_user32(sig, &info, uinfo); - if (unlikely(ret)) - return ret; - return do_rt_tgsigqueueinfo(tgid, pid, sig, &info); -} -#endif - -/* - * For kthreads only, must not be used if cloned with CLONE_SIGHAND - */ -void kernel_sigaction(int sig, __sighandler_t action) -{ - spin_lock_irq(¤t->sighand->siglock); - current->sighand->action[sig - 1].sa.sa_handler = action; - if (action == SIG_IGN) - { - sigset_t mask; - - sigemptyset(&mask); - sigaddset(&mask, sig); - - flush_sigqueue_mask(&mask, ¤t->signal->shared_pending); - flush_sigqueue_mask(&mask, ¤t->pending); - recalc_sigpending(); - } - spin_unlock_irq(¤t->sighand->siglock); -} -EXPORT_SYMBOL(kernel_sigaction); - -void __weak sigaction_compat_abi(struct k_sigaction *act, - struct k_sigaction *oact) -{ -} - -int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) -{ - struct task_struct *p = current, *t; - struct k_sigaction *k; - sigset_t mask; - - if (!valid_signal(sig) || sig < 1 || (act && sig_kernel_only(sig))) - return -EINVAL; - - k = &p->sighand->action[sig - 1]; - - spin_lock_irq(&p->sighand->siglock); - if (k->sa.sa_flags & SA_IMMUTABLE) - { - spin_unlock_irq(&p->sighand->siglock); - return -EINVAL; - } - if (oact) - *oact = *k; - - /* - * Make sure that we never accidentally claim to support SA_UNSUPPORTED, - * e.g. by having an architecture use the bit in their uapi. - */ - BUILD_BUG_ON(UAPI_SA_FLAGS & SA_UNSUPPORTED); - - /* - * Clear unknown flag bits in order to allow userspace to detect missing - * support for flag bits and to allow the kernel to use non-uapi bits - * internally. - */ - if (act) - act->sa.sa_flags &= UAPI_SA_FLAGS; - if (oact) - oact->sa.sa_flags &= UAPI_SA_FLAGS; - - sigaction_compat_abi(act, oact); - - if (act) - { - sigdelsetmask(&act->sa.sa_mask, - sigmask(SIGKILL) | sigmask(SIGSTOP)); - *k = *act; - /* - * POSIX 3.3.1.3: - * "Setting a signal action to SIG_IGN for a signal that is - * pending shall cause the pending signal to be discarded, - * whether or not it is blocked." - * - * "Setting a signal action to SIG_DFL for a signal that is - * pending and whose default action is to ignore the signal - * (for example, SIGCHLD), shall cause the pending signal to - * be discarded, whether or not it is blocked" - */ - if (sig_handler_ignored(sig_handler(p, sig), sig)) - { - sigemptyset(&mask); - sigaddset(&mask, sig); - flush_sigqueue_mask(&mask, &p->signal->shared_pending); - for_each_thread(p, t) - flush_sigqueue_mask(&mask, &t->pending); - } - } - - spin_unlock_irq(&p->sighand->siglock); - return 0; -} - -#ifdef CONFIG_DYNAMIC_SIGFRAME -static inline void sigaltstack_lock(void) - __acquires(¤t->sighand->siglock) -{ - spin_lock_irq(¤t->sighand->siglock); -} - -static inline void sigaltstack_unlock(void) - __releases(¤t->sighand->siglock) -{ - spin_unlock_irq(¤t->sighand->siglock); -} -#else -static inline void sigaltstack_lock(void) -{ -} -static inline void sigaltstack_unlock(void) {} -#endif - -static int -do_sigaltstack(const stack_t *ss, stack_t *oss, unsigned long sp, - size_t min_ss_size) -{ - struct task_struct *t = current; - int ret = 0; - - if (oss) - { - memset(oss, 0, sizeof(stack_t)); - oss->ss_sp = (void __user *)t->sas_ss_sp; - oss->ss_size = t->sas_ss_size; - oss->ss_flags = sas_ss_flags(sp) | - (current->sas_ss_flags & SS_FLAG_BITS); - } - - if (ss) - { - void __user *ss_sp = ss->ss_sp; - size_t ss_size = ss->ss_size; - unsigned ss_flags = ss->ss_flags; - int ss_mode; - - if (unlikely(on_sig_stack(sp))) - return -EPERM; - - ss_mode = ss_flags & ~SS_FLAG_BITS; - if (unlikely(ss_mode != SS_DISABLE && ss_mode != SS_ONSTACK && - ss_mode != 0)) - return -EINVAL; - - sigaltstack_lock(); - if (ss_mode == SS_DISABLE) - { - ss_size = 0; - ss_sp = NULL; - } - else - { - if (unlikely(ss_size < min_ss_size)) - ret = -ENOMEM; - if (!sigaltstack_size_valid(ss_size)) - ret = -ENOMEM; - } - if (!ret) - { - t->sas_ss_sp = (unsigned long)ss_sp; - t->sas_ss_size = ss_size; - t->sas_ss_flags = ss_flags; - } - sigaltstack_unlock(); - } - return ret; -} - -SYSCALL_DEFINE2(sigaltstack, const stack_t __user *, uss, stack_t __user *, uoss) -{ - stack_t new, old; - int err; - if (uss && copy_from_user(&new, uss, sizeof(stack_t))) - return -EFAULT; - err = do_sigaltstack(uss ? &new : NULL, uoss ? &old : NULL, - current_user_stack_pointer(), - MINSIGSTKSZ); - if (!err && uoss && copy_to_user(uoss, &old, sizeof(stack_t))) - err = -EFAULT; - return err; -} - -int restore_altstack(const stack_t __user *uss) -{ - stack_t new; - if (copy_from_user(&new, uss, sizeof(stack_t))) - return -EFAULT; - (void)do_sigaltstack(&new, NULL, current_user_stack_pointer(), - MINSIGSTKSZ); - /* squash all but EFAULT for now */ - return 0; -} - -int __save_altstack(stack_t __user *uss, unsigned long sp) -{ - struct task_struct *t = current; - int err = __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) | - __put_user(t->sas_ss_flags, &uss->ss_flags) | - __put_user(t->sas_ss_size, &uss->ss_size); - return err; -} - -#ifdef CONFIG_COMPAT -static int do_compat_sigaltstack(const compat_stack_t __user *uss_ptr, - compat_stack_t __user *uoss_ptr) -{ - stack_t uss, uoss; - int ret; - - if (uss_ptr) - { - compat_stack_t uss32; - if (copy_from_user(&uss32, uss_ptr, sizeof(compat_stack_t))) - return -EFAULT; - uss.ss_sp = compat_ptr(uss32.ss_sp); - uss.ss_flags = uss32.ss_flags; - uss.ss_size = uss32.ss_size; - } - ret = do_sigaltstack(uss_ptr ? &uss : NULL, &uoss, - compat_user_stack_pointer(), - COMPAT_MINSIGSTKSZ); - if (ret >= 0 && uoss_ptr) - { - compat_stack_t old; - memset(&old, 0, sizeof(old)); - old.ss_sp = ptr_to_compat(uoss.ss_sp); - old.ss_flags = uoss.ss_flags; - old.ss_size = uoss.ss_size; - if (copy_to_user(uoss_ptr, &old, sizeof(compat_stack_t))) - ret = -EFAULT; - } - return ret; -} - -COMPAT_SYSCALL_DEFINE2(sigaltstack, - const compat_stack_t __user *, uss_ptr, - compat_stack_t __user *, uoss_ptr) -{ - return do_compat_sigaltstack(uss_ptr, uoss_ptr); -} - -int compat_restore_altstack(const compat_stack_t __user *uss) -{ - int err = do_compat_sigaltstack(uss, NULL); - /* squash all but -EFAULT for now */ - return err == -EFAULT ? err : 0; -} - -int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp) -{ - int err; - struct task_struct *t = current; - err = __put_user(ptr_to_compat((void __user *)t->sas_ss_sp), - &uss->ss_sp) | - __put_user(t->sas_ss_flags, &uss->ss_flags) | - __put_user(t->sas_ss_size, &uss->ss_size); - return err; -} -#endif - -#ifdef __ARCH_WANT_SYS_SIGPENDING - -/** - * sys_sigpending - examine pending signals - * @uset: where mask of pending signal is returned - */ -SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, uset) -{ - sigset_t set; - - if (sizeof(old_sigset_t) > sizeof(*uset)) - return -EINVAL; - - do_sigpending(&set); - - if (copy_to_user(uset, &set, sizeof(old_sigset_t))) - return -EFAULT; - - return 0; -} - -#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set32) -{ - sigset_t set; - - do_sigpending(&set); - - return put_user(set.sig[0], set32); -} -#endif - -#endif - -#ifdef __ARCH_WANT_SYS_SIGPROCMASK -/** - * sys_sigprocmask - examine and change blocked signals - * @how: whether to add, remove, or set signals - * @nset: signals to add or remove (if non-null) - * @oset: previous value of signal mask if non-null - * - * Some platforms have their own version with special arguments; - * others support only sys_rt_sigprocmask. - */ - -SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset, - old_sigset_t __user *, oset) -{ - old_sigset_t old_set, new_set; - sigset_t new_blocked; - - old_set = current->blocked.sig[0]; - - if (nset) - { - if (copy_from_user(&new_set, nset, sizeof(*nset))) - return -EFAULT; - - new_blocked = current->blocked; - - switch (how) - { - case SIG_BLOCK: - sigaddsetmask(&new_blocked, new_set); - break; - case SIG_UNBLOCK: - sigdelsetmask(&new_blocked, new_set); - break; - case SIG_SETMASK: - new_blocked.sig[0] = new_set; - break; - default: - return -EINVAL; - } - - set_current_blocked(&new_blocked); - } - - if (oset) - { - if (copy_to_user(oset, &old_set, sizeof(*oset))) - return -EFAULT; - } - - return 0; -} -#endif /* __ARCH_WANT_SYS_SIGPROCMASK */ - -#ifndef CONFIG_ODD_RT_SIGACTION -/** - * sys_rt_sigaction - alter an action taken by a process - * @sig: signal to be sent - * @act: new sigaction - * @oact: used to save the previous sigaction - * @sigsetsize: size of sigset_t type - */ -SYSCALL_DEFINE4(rt_sigaction, int, sig, - const struct sigaction __user *, act, - struct sigaction __user *, oact, - size_t, sigsetsize) -{ - struct k_sigaction new_sa, old_sa; - int ret; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (act && copy_from_user(&new_sa.sa, act, sizeof(new_sa.sa))) - return -EFAULT; - - ret = do_sigaction(sig, act ? &new_sa : NULL, oact ? &old_sa : NULL); - if (ret) - return ret; - - if (oact && copy_to_user(oact, &old_sa.sa, sizeof(old_sa.sa))) - return -EFAULT; - - return 0; -} -#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, - const struct compat_sigaction __user *, act, - struct compat_sigaction __user *, oact, - compat_size_t, sigsetsize) -{ - struct k_sigaction new_ka, old_ka; -#ifdef __ARCH_HAS_SA_RESTORER - compat_uptr_t restorer; -#endif - int ret; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(compat_sigset_t)) - return -EINVAL; - - if (act) - { - compat_uptr_t handler; - ret = get_user(handler, &act->sa_handler); - new_ka.sa.sa_handler = compat_ptr(handler); -#ifdef __ARCH_HAS_SA_RESTORER - ret |= get_user(restorer, &act->sa_restorer); - new_ka.sa.sa_restorer = compat_ptr(restorer); -#endif - ret |= get_compat_sigset(&new_ka.sa.sa_mask, &act->sa_mask); - ret |= get_user(new_ka.sa.sa_flags, &act->sa_flags); - if (ret) - return -EFAULT; - } - - ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); - if (!ret && oact) - { - ret = put_user(ptr_to_compat(old_ka.sa.sa_handler), - &oact->sa_handler); - ret |= put_compat_sigset(&oact->sa_mask, &old_ka.sa.sa_mask, - sizeof(oact->sa_mask)); - ret |= put_user(old_ka.sa.sa_flags, &oact->sa_flags); -#ifdef __ARCH_HAS_SA_RESTORER - ret |= put_user(ptr_to_compat(old_ka.sa.sa_restorer), - &oact->sa_restorer); -#endif - } - return ret; -} -#endif -#endif /* !CONFIG_ODD_RT_SIGACTION */ - -#ifdef CONFIG_OLD_SIGACTION -SYSCALL_DEFINE3(sigaction, int, sig, - const struct old_sigaction __user *, act, - struct old_sigaction __user *, oact) -{ - struct k_sigaction new_ka, old_ka; - int ret; - - if (act) - { - old_sigset_t mask; - if (!access_ok(act, sizeof(*act)) || - __get_user(new_ka.sa.sa_handler, &act->sa_handler) || - __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) || - __get_user(new_ka.sa.sa_flags, &act->sa_flags) || - __get_user(mask, &act->sa_mask)) - return -EFAULT; -#ifdef __ARCH_HAS_KA_RESTORER - new_ka.ka_restorer = NULL; -#endif - siginitset(&new_ka.sa.sa_mask, mask); - } - - ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); - - if (!ret && oact) - { - if (!access_ok(oact, sizeof(*oact)) || - __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || - __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) || - __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || - __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) - return -EFAULT; - } - - return ret; -} -#endif -#ifdef CONFIG_COMPAT_OLD_SIGACTION -COMPAT_SYSCALL_DEFINE3(sigaction, int, sig, - const struct compat_old_sigaction __user *, act, - struct compat_old_sigaction __user *, oact) -{ - struct k_sigaction new_ka, old_ka; - int ret; - compat_old_sigset_t mask; - compat_uptr_t handler, restorer; - - if (act) - { - if (!access_ok(act, sizeof(*act)) || - __get_user(handler, &act->sa_handler) || - __get_user(restorer, &act->sa_restorer) || - __get_user(new_ka.sa.sa_flags, &act->sa_flags) || - __get_user(mask, &act->sa_mask)) - return -EFAULT; - -#ifdef __ARCH_HAS_KA_RESTORER - new_ka.ka_restorer = NULL; -#endif - new_ka.sa.sa_handler = compat_ptr(handler); - new_ka.sa.sa_restorer = compat_ptr(restorer); - siginitset(&new_ka.sa.sa_mask, mask); - } - - ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); - - if (!ret && oact) - { - if (!access_ok(oact, sizeof(*oact)) || - __put_user(ptr_to_compat(old_ka.sa.sa_handler), - &oact->sa_handler) || - __put_user(ptr_to_compat(old_ka.sa.sa_restorer), - &oact->sa_restorer) || - __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || - __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) - return -EFAULT; - } - return ret; -} -#endif - -#ifdef CONFIG_SGETMASK_SYSCALL - -/* - * For backwards compatibility. Functionality superseded by sigprocmask. - */ -SYSCALL_DEFINE0(sgetmask) -{ - /* SMP safe */ - return current->blocked.sig[0]; -} - -SYSCALL_DEFINE1(ssetmask, int, newmask) -{ - int old = current->blocked.sig[0]; - sigset_t newset; - - siginitset(&newset, newmask); - set_current_blocked(&newset); - - return old; -} -#endif /* CONFIG_SGETMASK_SYSCALL */ - -#ifdef __ARCH_WANT_SYS_SIGNAL -/* - * For backwards compatibility. Functionality superseded by sigaction. - */ -SYSCALL_DEFINE2(signal, int, sig, __sighandler_t, handler) -{ - struct k_sigaction new_sa, old_sa; - int ret; - - new_sa.sa.sa_handler = handler; - new_sa.sa.sa_flags = SA_ONESHOT | SA_NOMASK; - sigemptyset(&new_sa.sa.sa_mask); - - ret = do_sigaction(sig, &new_sa, &old_sa); - - return ret ? ret : (unsigned long)old_sa.sa.sa_handler; -} -#endif /* __ARCH_WANT_SYS_SIGNAL */ - -#ifdef __ARCH_WANT_SYS_PAUSE - -SYSCALL_DEFINE0(pause) -{ - while (!signal_pending(current)) - { - __set_current_state(TASK_INTERRUPTIBLE); - schedule(); - } - return -ERESTARTNOHAND; -} - -#endif - -static int sigsuspend(sigset_t *set) -{ - current->saved_sigmask = current->blocked; - set_current_blocked(set); - - while (!signal_pending(current)) - { - __set_current_state(TASK_INTERRUPTIBLE); - schedule(); - } - set_restore_sigmask(); - return -ERESTARTNOHAND; -} - -/** - * sys_rt_sigsuspend - replace the signal mask for a value with the - * @unewset value until a signal is received - * @unewset: new signal mask value - * @sigsetsize: size of sigset_t type - */ -SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *, unewset, size_t, sigsetsize) -{ - sigset_t newset; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (copy_from_user(&newset, unewset, sizeof(newset))) - return -EFAULT; - return sigsuspend(&newset); -} - -#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE2(rt_sigsuspend, compat_sigset_t __user *, unewset, compat_size_t, sigsetsize) -{ - sigset_t newset; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (get_compat_sigset(&newset, unewset)) - return -EFAULT; - return sigsuspend(&newset); -} -#endif - -#ifdef CONFIG_OLD_SIGSUSPEND -SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask) -{ - sigset_t blocked; - siginitset(&blocked, mask); - return sigsuspend(&blocked); -} -#endif -#ifdef CONFIG_OLD_SIGSUSPEND3 -SYSCALL_DEFINE3(sigsuspend, int, unused1, int, unused2, old_sigset_t, mask) -{ - sigset_t blocked; - siginitset(&blocked, mask); - return sigsuspend(&blocked); -} -#endif - -__weak const char *arch_vma_name(struct vm_area_struct *vma) -{ - return NULL; -} - -static inline void siginfo_buildtime_checks(void) -{ - BUILD_BUG_ON(sizeof(struct siginfo) != SI_MAX_SIZE); - - /* Verify the offsets in the two siginfos match */ -#define CHECK_OFFSET(field) \ - BUILD_BUG_ON(offsetof(siginfo_t, field) != offsetof(kernel_siginfo_t, field)) - - /* kill */ - CHECK_OFFSET(si_pid); - CHECK_OFFSET(si_uid); - - /* timer */ - CHECK_OFFSET(si_tid); - CHECK_OFFSET(si_overrun); - CHECK_OFFSET(si_value); - - /* rt */ - CHECK_OFFSET(si_pid); - CHECK_OFFSET(si_uid); - CHECK_OFFSET(si_value); - - /* sigchld */ - CHECK_OFFSET(si_pid); - CHECK_OFFSET(si_uid); - CHECK_OFFSET(si_status); - CHECK_OFFSET(si_utime); - CHECK_OFFSET(si_stime); - - /* sigfault */ - CHECK_OFFSET(si_addr); - CHECK_OFFSET(si_trapno); - CHECK_OFFSET(si_addr_lsb); - CHECK_OFFSET(si_lower); - CHECK_OFFSET(si_upper); - CHECK_OFFSET(si_pkey); - CHECK_OFFSET(si_perf_data); - CHECK_OFFSET(si_perf_type); - - /* sigpoll */ - CHECK_OFFSET(si_band); - CHECK_OFFSET(si_fd); - - /* sigsys */ - CHECK_OFFSET(si_call_addr); - CHECK_OFFSET(si_syscall); - CHECK_OFFSET(si_arch); -#undef CHECK_OFFSET - - /* usb asyncio */ - BUILD_BUG_ON(offsetof(struct siginfo, si_pid) != - offsetof(struct siginfo, si_addr)); - if (sizeof(int) == sizeof(void __user *)) - { - BUILD_BUG_ON(sizeof_field(struct siginfo, si_pid) != - sizeof(void __user *)); - } - else - { - BUILD_BUG_ON((sizeof_field(struct siginfo, si_pid) + - sizeof_field(struct siginfo, si_uid)) != - sizeof(void __user *)); - BUILD_BUG_ON(offsetofend(struct siginfo, si_pid) != - offsetof(struct siginfo, si_uid)); - } -#ifdef CONFIG_COMPAT - BUILD_BUG_ON(offsetof(struct compat_siginfo, si_pid) != - offsetof(struct compat_siginfo, si_addr)); - BUILD_BUG_ON(sizeof_field(struct compat_siginfo, si_pid) != - sizeof(compat_uptr_t)); - BUILD_BUG_ON(sizeof_field(struct compat_siginfo, si_pid) != - sizeof_field(struct siginfo, si_pid)); -#endif -} - -void __init signals_init(void) -{ - siginfo_buildtime_checks(); - - sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC | SLAB_ACCOUNT); -} - -#ifdef CONFIG_KGDB_KDB -#include -/* - * kdb_send_sig - Allows kdb to send signals without exposing - * signal internals. This function checks if the required locks are - * available before calling the main signal code, to avoid kdb - * deadlocks. - */ -void kdb_send_sig(struct task_struct *t, int sig) -{ - static struct task_struct *kdb_prev_t; - int new_t, ret; - if (!spin_trylock(&t->sighand->siglock)) - { - kdb_printf("Can't do kill command now.\n" - "The sigmask lock is held somewhere else in " - "kernel, try again later\n"); - return; - } - new_t = kdb_prev_t != t; - kdb_prev_t = t; - if (!task_is_running(t) && new_t) - { - spin_unlock(&t->sighand->siglock); - kdb_printf("Process is not RUNNING, sending a signal from " - "kdb risks deadlock\n" - "on the run queue locks. " - "The signal has _not_ been sent.\n" - "Reissue the kill command if you want to risk " - "the deadlock.\n"); - return; - } - ret = send_signal(sig, SEND_SIG_PRIV, t, PIDTYPE_PID); - spin_unlock(&t->sighand->siglock); - if (ret) - kdb_printf("Fail to deliver Signal %d to process %d.\n", - sig, t->pid); - else - kdb_printf("Signal %d is sent to process %d.\n", sig, t->pid); -} -#endif /* CONFIG_KGDB_KDB */ diff --git a/ableos/src/arch/x86_64/drivers/vga.rs b/ableos/src/arch/x86_64/drivers/vga.rs index ee5a1b2..669b8ba 100644 --- a/ableos/src/arch/x86_64/drivers/vga.rs +++ b/ableos/src/arch/x86_64/drivers/vga.rs @@ -125,7 +125,7 @@ lazy_static! { use core::fmt; use lazy_static::lazy_static; use spin::Mutex; -use vga::writers::Screen; + use volatile::Volatile; #[macro_export] diff --git a/ableos/src/arch/x86_64/interrupts.rs b/ableos/src/arch/x86_64/interrupts.rs index 7f3775c..1ebfd15 100644 --- a/ableos/src/arch/x86_64/interrupts.rs +++ b/ableos/src/arch/x86_64/interrupts.rs @@ -1,11 +1,9 @@ use crate::{ arch::{drivers::vga::WRITER, gdt}, kernel_state::KERNEL_STATE, - kmain::KEY_BUFFER, print, println, - relib::clparse, }; -use alloc::string::ToString; + use lazy_static::lazy_static; use pic8259::ChainedPics; use spin; @@ -101,7 +99,7 @@ extern "x86-interrupt" fn keyboard_interrupt_handler(_stack_frame: InterruptStac // Enter 0x0A => { - let xyz = crate::kmain::KEY_BUFFER.lock(); + let _xyz = crate::kmain::KEY_BUFFER.lock(); // println!("{:?}", clparse::Command::parse(xyz.to_string())); print!("{}", char::try_from(character).unwrap()); diff --git a/ableos/src/boot_conf.rs b/ableos/src/boot_conf.rs index 2b66886..4762e46 100644 --- a/ableos/src/boot_conf.rs +++ b/ableos/src/boot_conf.rs @@ -1,5 +1,5 @@ use log::LevelFilter; -use serde::{de::value::BoolDeserializer, Deserialize, Serialize}; +use serde::{Deserialize, Serialize}; #[derive(Serialize, Debug, Deserialize)] pub enum LogLevel { diff --git a/ableos/src/graphics/mod.rs b/ableos/src/graphics/mod.rs index 14db258..d625edd 100644 --- a/ableos/src/graphics/mod.rs +++ b/ableos/src/graphics/mod.rs @@ -2,10 +2,10 @@ use crate::vga_e::VGAE; use alloc::{boxed::Box, vec, vec::Vec}; use shadeable::{ evaluate_shader, - pixel_format::{new_rgba64, Rgba64}, + pixel_format::{Rgba64}, }; use spin; -use vga::{colors::Color16, writers::GraphicsWriter}; +use vga::{writers::GraphicsWriter}; #[derive(Debug)] pub struct ScreenSize { @@ -137,7 +137,7 @@ impl VgaBuffer for ScreenBuffer { let mode = VGAE.lock(); for y in 0..self.size.y { for x in 0..self.size.x { - use shadeable::pixel_format::{get_color16, into_vga_16}; + use shadeable::pixel_format::{into_vga_16}; // let vga_color = get_color16(self.buff[y * self.size.x + x]); let vga_color = into_vga_16(self.buff[y * self.size.x + x]); diff --git a/ableos/src/kmain.rs b/ableos/src/kmain.rs index 941d47b..62d0d4c 100644 --- a/ableos/src/kmain.rs +++ b/ableos/src/kmain.rs @@ -79,8 +79,8 @@ pub fn kernel_main() -> ! { graphics.force_redraw(); graphics.clear(); - graphics.draw_filled_circle(100, 100, 5, 0x9900ff00); screen_writer_test(); + graphics.draw_filled_circle(100, 100, 50, 0x9900ff00); graphics.copy_to_buffer(); @@ -135,7 +135,7 @@ pub fn cpu_socket_startup() { cpu_info_socket.register_protocol("CPU_INFO".to_string()); let x = master().unwrap(); - let xyz = x.brand_string().unwrap(); + let _xyz = x.brand_string().unwrap(); } pub fn log_version_data() { @@ -199,8 +199,8 @@ pub fn screen_writer_test() { sock_print_id.register_protocol("Screen Printer".to_string()); // sock_print_id.write(format!("a原 b画 cフ dァ eイ fル 集").into()); - sock_print_id.write(format!("λ³ Half Life 3 booting up ㎣").into()); - // sock_print_id.write(format!("Happy birthday 🎉").into()); + // sock_print_id.write(format!("λ³ Half Life 3 booting up ㎣").into()); + sock_print_id.write(format!("Happy birthday 🎉").into()); // sock_print_id.write(format!("1....2....3....4....5....6....7....8....9").into()); let mut prev = None; diff --git a/ableos/src/relib/encoding/bin.rs b/ableos/src/relib/encoding/bin.rs index 3d731cf..6743bb6 100644 --- a/ableos/src/relib/encoding/bin.rs +++ b/ableos/src/relib/encoding/bin.rs @@ -1,5 +1,5 @@ -use alloc::{boxed::Box, vec::Vec}; -use core::result; +use alloc::{boxed::Box}; + pub struct BinCodeWriter { pub stream: Box,