RepoMirrors
/
gperftools
mirror of https://github.com/gperftools/gperftools
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

[stacktrace_generic_fp] clear aarch64 pointer auth bits 

AARCH64 >= armv8.3-a supports pointer authentication. If this feature is
enabled it modifies the previously unused upper address bits in apointer.
The affected bits need to be cleared in order for stacktrace to work.

Signed-off-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
[alkondratenko@gmail.com: added succinct subject line]
This commit is contained in:
Julian Schroeder 2023-10-30 11:43:42 -06:00 committed by Aliaksey Kandratsenka
parent d1a0cbe1bf
commit 000af9a164
1 changed files with 24 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
src/stacktrace_generic_fp-inl.h
View File

@ -77,6 +77,27 @@ namespace stacktrace_generic_fp {
#define PAD_FRAME
#endif
#if __aarch64__
// Aarch64 has pointer authentication and uses the upper 16bit of a stack
// or return address to sign it. These bits needs to be strip in order for
// stacktraces to work.
void *strip_PAC(void* _ptr) {
void *ret;
asm volatile(
"mov x30, %1\n\t"
"hint #7\n\t" // xpaclri, is NOP for < armv8.3-a
"mov %0, x30\n\t"
: "=r"(ret)
: "r"(_ptr)
: "x30");
return ret;
}
#define STRIP_PAC(x) (strip_PAC((x)))
#else
#define STRIP_PAC(x) (x)
#endif
struct frame {
uintptr_t parent;
#ifdef PAD_FRAME
@ -131,7 +152,8 @@ int capture(void **result, int max_depth, int skip_count,
if (max_depth == 0) {
return 0;
}
result[0] = *initial_pc;
result[0] = STRIP_PAC(*initial_pc);
i++;
}
@ -189,7 +211,7 @@ int capture(void **result, int max_depth, int skip_count,
if (WithSizes) {
sizes[i - skip_count] = reinterpret_cast<uintptr_t>(prev_f) - reinterpret_cast<uintptr_t>(f);
}
result[i - skip_count] = pc;
result[i - skip_count] = STRIP_PAC(pc);
}
i++;