https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96191
--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-9 branch has been updated by Richard Sandiford <rsand...@gcc.gnu.org>: https://gcc.gnu.org/g:3e40be9cc92d3fa117be7f4fab07cedeed8361a2 commit r9-8795-g3e40be9cc92d3fa117be7f4fab07cedeed8361a2 Author: Richard Sandiford <richard.sandif...@arm.com> Date: Fri Aug 7 12:17:37 2020 +0100 arm: 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/arm/arm.md (arm_stack_protect_test_insn): Zero out operand 2 after use. * config/arm/thumb1.md (thumb1_stack_protect_test_insn): Likewise. gcc/testsuite/ * gcc.target/arm/stack-protector-1.c: New test. * gcc.target/arm/stack-protector-2.c: Likewise. (cherry picked from commit 6a3f3e08723063ea2dadb7ddf503f02972a724e2)
