Skip to content

[PAC][libunwind] Enhance PAuth-related comments in __unw_set_reg #173769

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
kovdan01 merged 1 commit into from
Dec 29, 2025
+9 −6
Merged

[PAC][libunwind] Enhance PAuth-related comments in __unw_set_reg #173769

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
15 changes: 9 additions & 6 deletions libunwind/src/libunwind.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -150,16 +150,19 @@ _LIBUNWIND_HIDDEN int __unw_set_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
_LIBUNWIND_ABORT("PC vs frame info mismatch");

// PC should have been signed with the sp, so we verify that
// roundtripping does not fail.
// roundtripping does not fail. The `ptrauth_auth_and_resign` is
// guaranteed to trap on authentication failure even without FPAC
// feature.
pint_t pc = (pint_t)co->getReg(UNW_REG_IP);
if (ptrauth_auth_and_resign((void *)pc, ptrauth_key_return_address, sp,
ptrauth_key_return_address,
sp) != (void *)pc) {
_LIBUNWIND_LOG("Bad unwind through arm64e (0x%zX, 0x%zX)->0x%zX\n",
pc, sp,
(pint_t)ptrauth_auth_data(
(void *)pc, ptrauth_key_return_address, sp));
_LIBUNWIND_ABORT("Bad unwind through arm64e");
_LIBUNWIND_LOG(
"Bad unwind with PAuth-enabled ABI (0x%zX, 0x%zX)->0x%zX\n", pc,
sp,
(pint_t)ptrauth_auth_data((void *)pc, ptrauth_key_return_address,
sp));
_LIBUNWIND_ABORT("Bad unwind with PAuth-enabled ABI");
}
}
#endif
Expand Down
Loading