RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-25 18:57:45 +00:00
Code Issues Activity Actions

UserspaceEmulator: Forget ChunkedBlocks after they are munmap()'ed

Browse source 
This is not ideal since we lose free() backtraces, but it will require
some thinking to get this right.
This commit is contained in:
Andreas Kling 2020-11-14 23:07:07 +01:00
parent 2066f48b87
commit 8fd97bee7f
3 changed files with 16 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

8
DevTools/UserspaceEmulator/MallocTracer.cpp
View file

@ -40,6 +40,14 @@ MallocTracer::MallocTracer()
{ {
} }
void MallocTracer::notify_malloc_block_was_released(Badge<MmapRegion>, MmapRegion& region)
{
// FIXME: It's sad that we may lose a bunch of free() backtraces here,
// but if the address is reused for a new ChunkedBlock, things will
// get extremely confused.
m_chunked_blocks.remove(region.base());
}
void MallocTracer::target_did_malloc(Badge<SoftCPU>, FlatPtr address, size_t size) void MallocTracer::target_did_malloc(Badge<SoftCPU>, FlatPtr address, size_t size)
{ {
auto* region = Emulator::the().mmu().find_region({ 0x20, address }); auto* region = Emulator::the().mmu().find_region({ 0x20, address });

3
DevTools/UserspaceEmulator/MallocTracer.h
View file

@ -34,6 +34,7 @@
namespace UserspaceEmulator { namespace UserspaceEmulator {
class MmapRegion;
class SoftCPU; class SoftCPU;
class MallocTracer { class MallocTracer {
@ -44,6 +45,8 @@ public:
void target_did_free(Badge<SoftCPU>, FlatPtr address); void target_did_free(Badge<SoftCPU>, FlatPtr address);
void target_did_realloc(Badge<SoftCPU>, FlatPtr address, size_t); void target_did_realloc(Badge<SoftCPU>, FlatPtr address, size_t);
void notify_malloc_block_was_released(Badge<MmapRegion>, MmapRegion&);
void audit_read(FlatPtr address, size_t); void audit_read(FlatPtr address, size_t);
void audit_write(FlatPtr address, size_t); void audit_write(FlatPtr address, size_t);

5
DevTools/UserspaceEmulator/MmapRegion.cpp
View file

@ -58,6 +58,11 @@ MmapRegion::MmapRegion(u32 base, u32 size, int prot)
MmapRegion::~MmapRegion() MmapRegion::~MmapRegion()
{ {
if (is_malloc_block()) {
if (auto* tracer = Emulator::the().malloc_tracer())
tracer->notify_malloc_block_was_released({}, *this);
}
free(m_shadow_data); free(m_shadow_data);
if (m_file_backed) if (m_file_backed)
munmap(m_data, size()); munmap(m_data, size());