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fix is_pointer_to_instructions check #2

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fix is_pointer_to_instructions check #2

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9eb09b7
fix is_pointer_to_instructions check
staturnzz Aug 5, 2026
97c4575
fix section attr masking
staturnzz Aug 5, 2026
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19 changes: 10 additions & 9 deletions src/litehook.c
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Original file line number Diff line number Diff line change
Expand Up @@ -243,13 +243,12 @@ bool is_pointer_to_instructions(const mach_header_u *header, uintptr_t ptr)
(const struct section_64 *)((const uint8_t *)seg + sizeof(struct segment_command_64));

for (uint32_t s = 0; s < seg->nsects; s++, sect++) {
uint64_t sectStart = (uintptr_t)header + sect->addr;
uint64_t sectStart = sect->addr;
uint64_t sectEnd = sectStart + sect->size;

if ((ptr >= sect->addr) && (ptr < sectEnd)) {
uint32_t attrs = sect->flags & SECTION_ATTRIBUTES_USR;
return (attrs & S_ATTR_PURE_INSTRUCTIONS) ||
(attrs & S_ATTR_SOME_INSTRUCTIONS);
if ((ptr >= sectStart) && (ptr < sectEnd)) {
return (sect->flags & S_ATTR_PURE_INSTRUCTIONS) ||
(sect->flags & S_ATTR_SOME_INSTRUCTIONS);
}
}
}
Expand All @@ -259,7 +258,7 @@ bool is_pointer_to_instructions(const mach_header_u *header, uintptr_t ptr)
return false;
}

void *_litehook_sign_if_executable(void *ptr, const mach_header_u *optHeader)
void *_litehook_sign_if_executable(void *ptr, uintptr_t slide, const mach_header_u *optHeader)
{
const mach_header_u *header = optHeader;
if (!header) {
Expand All @@ -269,7 +268,7 @@ void *_litehook_sign_if_executable(void *ptr, const mach_header_u *optHeader)
}
header = (const mach_header_u *)info.dli_fbase;
}
if (!is_pointer_to_instructions(header, (uintptr_t)ptr)) {
if (!is_pointer_to_instructions(header, (uintptr_t)ptr - slide)) {
return ptr;
}
return ptrauth_sign_unauthenticated(ptr, ptrauth_key_function_pointer, 0);
Expand Down Expand Up @@ -330,7 +329,8 @@ void *litehook_find_symbol(const mach_header_u *header, const char *symbolName)
}

if (!strcmp(curSymbolName, symbolName)) {
return _litehook_sign_if_executable((void *)((uintptr_t)header + symEntry->n_value), header);
if (slide == -1) slide = 0;
return _litehook_sign_if_executable((void *)((uintptr_t)header + symEntry->n_value), slide, header);
}
}

Expand Down Expand Up @@ -414,7 +414,8 @@ void *litehook_find_dsc_symbol(const char *imagePath, const char *symbolName)
char curSymbolName[len+1];
if (fread(curSymbolName, len+1, 1, symbolDSC) != 1) goto end;
if (!strcmp(curSymbolName, symbolName)) {
symbol = _litehook_sign_if_executable((void *)(litehook_get_dsc_slide() + n.n_value), NULL);
uintptr_t slide = litehook_get_dsc_slide();
symbol = _litehook_sign_if_executable((void *)(slide + n.n_value), slide, NULL);
}
}

Expand Down