forked from AbleOS/holey-bytes
Fixed memory (un)mapping
This commit is contained in:
parent
19df4538d7
commit
1ed153a9a2
|
@ -10,25 +10,41 @@ use {
|
||||||
|
|
||||||
fuzz_target!(|data: &[u8]| {
|
fuzz_target!(|data: &[u8]| {
|
||||||
if let Ok(mut vm) = Vm::<_, 16384>::new_validated(data, TestTrapHandler, Default::default()) {
|
if let Ok(mut vm) = Vm::<_, 16384>::new_validated(data, TestTrapHandler, Default::default()) {
|
||||||
let page = Box::into_raw(Box::<Page>::default());
|
// Alloc and map some memory
|
||||||
|
let pages = [
|
||||||
|
alloc_and_map(&mut vm.memory, 0),
|
||||||
|
alloc_and_map(&mut vm.memory, 4096),
|
||||||
|
];
|
||||||
|
|
||||||
|
// Run VM
|
||||||
|
let _ = vm.run();
|
||||||
|
|
||||||
|
// Unmap and dealloc the memory
|
||||||
|
for (i, page) in pages.into_iter().enumerate() {
|
||||||
|
unmap_and_dealloc(&mut vm.memory, page, i as u64 * 4096);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
});
|
||||||
|
|
||||||
|
fn alloc_and_map(memory: &mut Memory, at: u64) -> *mut u8 {
|
||||||
|
let ptr = Box::into_raw(Box::<Page>::default()).cast();
|
||||||
unsafe {
|
unsafe {
|
||||||
vm.memory
|
memory
|
||||||
.map(
|
.map(
|
||||||
page.cast(),
|
ptr,
|
||||||
0,
|
at,
|
||||||
hbvm::mem::paging::Permission::Write,
|
hbvm::mem::paging::Permission::Write,
|
||||||
PageSize::Size4K,
|
PageSize::Size4K,
|
||||||
)
|
)
|
||||||
.unwrap()
|
.unwrap()
|
||||||
};
|
};
|
||||||
|
ptr
|
||||||
|
}
|
||||||
|
|
||||||
let _ = vm.run();
|
fn unmap_and_dealloc(memory: &mut Memory, ptr: *mut u8, from: u64) {
|
||||||
|
memory.unmap(from).unwrap();
|
||||||
vm.memory.unmap(0).unwrap();
|
let _ = unsafe { Box::from_raw(ptr.cast::<Page>()) };
|
||||||
let _ = unsafe { Box::from_raw(page) };
|
}
|
||||||
}
|
|
||||||
});
|
|
||||||
|
|
||||||
#[repr(align(4096))]
|
#[repr(align(4096))]
|
||||||
struct Page([u8; 4096]);
|
struct Page([u8; 4096]);
|
||||||
|
|
|
@ -1,7 +1,7 @@
|
||||||
//! Program memory implementation
|
//! Program memory implementation
|
||||||
|
|
||||||
pub mod paging;
|
|
||||||
pub mod bmc;
|
pub mod bmc;
|
||||||
|
pub mod paging;
|
||||||
|
|
||||||
mod pfhandler;
|
mod pfhandler;
|
||||||
|
|
||||||
|
@ -58,13 +58,13 @@ impl Memory {
|
||||||
|
|
||||||
// Decide on what level depth are we going
|
// Decide on what level depth are we going
|
||||||
let lookup_depth = match pagesize {
|
let lookup_depth = match pagesize {
|
||||||
PageSize::Size4K => 4,
|
PageSize::Size4K => 0,
|
||||||
PageSize::Size2M => 3,
|
PageSize::Size2M => 1,
|
||||||
PageSize::Size1G => 2,
|
PageSize::Size1G => 2,
|
||||||
};
|
};
|
||||||
|
|
||||||
// Walk pagetable levels
|
// Walk pagetable levels
|
||||||
for lvl in (0..lookup_depth).rev() {
|
for lvl in (lookup_depth..5).rev() {
|
||||||
let entry = (*current_pt)
|
let entry = (*current_pt)
|
||||||
.table
|
.table
|
||||||
.get_unchecked_mut(addr_extract_index(target, lvl));
|
.get_unchecked_mut(addr_extract_index(target, lvl));
|
||||||
|
@ -94,7 +94,7 @@ impl Memory {
|
||||||
|
|
||||||
let node = (*current_pt)
|
let node = (*current_pt)
|
||||||
.table
|
.table
|
||||||
.get_unchecked_mut(addr_extract_index(target, 4 - lookup_depth));
|
.get_unchecked_mut(addr_extract_index(target, lookup_depth));
|
||||||
|
|
||||||
// Check if node is not mapped
|
// Check if node is not mapped
|
||||||
if node.permission() != Permission::Empty {
|
if node.permission() != Permission::Empty {
|
||||||
|
@ -114,6 +114,7 @@ impl Memory {
|
||||||
/// just should be ignored.
|
/// just should be ignored.
|
||||||
#[cfg(feature = "alloc")]
|
#[cfg(feature = "alloc")]
|
||||||
pub fn unmap(&mut self, addr: u64) -> Result<(), NothingToUnmap> {
|
pub fn unmap(&mut self, addr: u64) -> Result<(), NothingToUnmap> {
|
||||||
|
extern crate std;
|
||||||
let mut current_pt = self.root_pt;
|
let mut current_pt = self.root_pt;
|
||||||
let mut page_tables = [core::ptr::null_mut(); 5];
|
let mut page_tables = [core::ptr::null_mut(); 5];
|
||||||
|
|
||||||
|
@ -152,9 +153,7 @@ impl Memory {
|
||||||
|
|
||||||
unsafe {
|
unsafe {
|
||||||
let children = &mut (*(*entry).ptr()).pt.childen;
|
let children = &mut (*(*entry).ptr()).pt.childen;
|
||||||
|
*children -= 1; // Decrease children count
|
||||||
// Decrease children count
|
|
||||||
*children -= 1;
|
|
||||||
|
|
||||||
// If there are no children, deallocate.
|
// If there are no children, deallocate.
|
||||||
if *children == 0 {
|
if *children == 0 {
|
||||||
|
@ -162,6 +161,8 @@ impl Memory {
|
||||||
|
|
||||||
// Zero visited entry
|
// Zero visited entry
|
||||||
core::ptr::write_bytes(entry, 0, 1);
|
core::ptr::write_bytes(entry, 0, 1);
|
||||||
|
} else {
|
||||||
|
break;
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
Loading…
Reference in a new issue