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mte: add untag_pointer() variant for const pointers

pull/226/head
Dmitry Muhomor 2023-10-30 12:52:09 +02:00 committed by Daniel Micay
parent be08eeee2d
commit 72dc236d5f
2 changed files with 10 additions and 1 deletions
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2
h_malloc.c
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@ -1762,7 +1762,7 @@ EXPORT size_t h_malloc_usable_size(H_MALLOC_USABLE_SIZE_CONST void *arg) {
return 0; 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) { if (p < get_slab_region_end() && p >= ro.slab_region_start) {
thread_unseal_metadata(); thread_unseal_metadata();

9
memtag.h
View File

@ -19,6 +19,15 @@ static inline void *untag_pointer(void *ptr) {
#endif #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) { static inline void *set_pointer_tag(void *ptr, u8 tag) {
#ifdef HAS_ARM_MTE #ifdef HAS_ARM_MTE
return (void *) (((uintptr_t) tag << 56) | (uintptr_t) untag_pointer(ptr)); return (void *) (((uintptr_t) tag << 56) | (uintptr_t) untag_pointer(ptr));