jmb/hardened_malloc
1
0
Fork 0
mirror of https://github.com/GrapheneOS/hardened_malloc.git synced 2025-11-03 01:06:33 +01:00
Code Issues Projects Releases Packages Wiki Activity

mte: add untag_pointer() variant for const pointers

Browse source
This commit is contained in:
Dmitry Muhomor 2023-10-30 12:52:09 +02:00
parent 99ab17364e
commit 452ff8a878
2 changed files with 10 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
h_malloc.c
View file

@ -1762,7 +1762,7 @@ EXPORT size_t h_malloc_usable_size(H_MALLOC_USABLE_SIZE_CONST void *arg) {
return 0;
}
void *p = untag_pointer((void *) (uintptr_t) arg);
const void *p = untag_const_pointer(arg);
if (p < get_slab_region_end() && p >= ro.slab_region_start) {
thread_unseal_metadata();

9
memtag.h
View file

@ -19,6 +19,15 @@ static inline void *untag_pointer(void *ptr) {
#endif
}
static inline const void *untag_const_pointer(const void *ptr) {
#ifdef HAS_ARM_MTE
const uintptr_t mask = UINTPTR_MAX >> 8;
return (const void *) ((uintptr_t) ptr & mask);
#else
return ptr;
#endif
}
static inline void *set_pointer_tag(void *ptr, u8 tag) {
#ifdef HAS_ARM_MTE
return (void *) (((uintptr_t) tag << 56) | (uintptr_t) untag_pointer(ptr));