https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96191
--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-10 branch has been updated by Richard Sandiford <rsand...@gcc.gnu.org>: https://gcc.gnu.org/g:bab5fdaf9abb1236a7a56258d1d36265068b4827 commit r10-8583-gbab5fdaf9abb1236a7a56258d1d36265068b4827 Author: Richard Sandiford <richard.sandif...@arm.com> Date: Fri Aug 7 12:15:01 2020 +0100 aarch64: Clear canary value after stack_protect_test [PR96191] The stack_protect_test patterns were leaving the canary value in the temporary register, meaning that it was often still in registers on return from the function. An attacker might therefore have been able to use it to defeat stack-smash protection for a later function. gcc/ PR target/96191 * config/aarch64/aarch64.md (stack_protect_test_<mode>): Set the CC register directly, instead of a GPR. Replace the original GPR destination with an extra scratch register. Zero out operand 3 after use. (stack_protect_test): Update accordingly. gcc/testsuite/ PR target/96191 * gcc.target/aarch64/stack-protector-1.c: New test. * gcc.target/aarch64/stack-protector-2.c: Likewise. (cherry picked from commit fe1a26429038d7cd17abc53f96a6f3e2639b605f)
