Commit 49cee364 authored by Yeoreum Yun's avatar Yeoreum Yun Committed by Catalin Marinas
Browse files

kselftest/arm64/mte: Add verification for address tag in signal handler 



Add the address tag [63:60] verification when synchronous mte fault is happen.
when signal handler is registered with SA_EXPOSE_TAGBITS,
address includes not only memory tag [59:56] but also address tag.
Therefore, when verify fault address location, remove both tags

Signed-off-by: default avatarYeoreum Yun <yeoreum.yun@arm.com>
Reviewed-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20250618084513.1761345-9-yeoreum.yun@arm.com


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent ed434c6e

tools/testing/selftests/arm64/mte/mte_common_util.c

+28 −10
Original line number Diff line number Diff line
@@ -33,12 +33,25 @@ static unsigned int mte_cur_pstate_tco; 


void mte_default_handler(int signum, siginfo_t *si, void *uc)

{

	struct sigaction sa;

	unsigned long addr = (unsigned long)si->si_addr;

	unsigned char si_tag, si_atag;



	sigaction(signum, NULL, &sa);



	if (sa.sa_flags & SA_EXPOSE_TAGBITS) {

		si_tag = MT_FETCH_TAG(addr);

		si_atag = MT_FETCH_ATAG(addr);

		addr = MT_CLEAR_TAGS(addr);

	} else {

		si_tag = 0;

		si_atag = 0;

	}



	if (signum == SIGSEGV) {

#ifdef DEBUG

		ksft_print_msg("INFO: SIGSEGV signal at pc=%lx, fault addr=%lx, si_code=%lx\n",

				((ucontext_t *)uc)->uc_mcontext.pc, addr, si->si_code);

		ksft_print_msg("INFO: SIGSEGV signal at pc=%lx, fault addr=%lx, si_code=%lx, si_tag=%x, si_atag=%x\n",

				((ucontext_t *)uc)->uc_mcontext.pc, addr, si->si_code, si_tag, si_atag);

#endif

		if (si->si_code == SEGV_MTEAERR) {

			if (cur_mte_cxt.trig_si_code == si->si_code)
@@ -51,13 +64,18 @@ void mte_default_handler(int signum, siginfo_t *si, void *uc) 
		}

		/* Compare the context for precise error */

		else if (si->si_code == SEGV_MTESERR) {

			if ((!mtefar_support && si_atag) || (si_atag != MT_FETCH_ATAG(cur_mte_cxt.trig_addr))) {

				ksft_print_msg("Invalid MTE synchronous exception caught for address tag! si_tag=%x, si_atag: %x\n", si_tag, si_atag);

				exit(KSFT_FAIL);

			}



			if (cur_mte_cxt.trig_si_code == si->si_code &&

			    ((cur_mte_cxt.trig_range >= 0 &&

			      addr >= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) &&

			      addr <= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)) ||

			      addr >= MT_CLEAR_TAGS(cur_mte_cxt.trig_addr) &&

			      addr <= (MT_CLEAR_TAGS(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)) ||

			     (cur_mte_cxt.trig_range < 0 &&

			      addr <= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) &&

			      addr >= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)))) {

			      addr <= MT_CLEAR_TAGS(cur_mte_cxt.trig_addr) &&

			      addr >= (MT_CLEAR_TAGS(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)))) {

				cur_mte_cxt.fault_valid = true;

				/* Adjust the pc by 4 */

				((ucontext_t *)uc)->uc_mcontext.pc += 4;
@@ -73,11 +91,11 @@ void mte_default_handler(int signum, siginfo_t *si, void *uc) 
		ksft_print_msg("INFO: SIGBUS signal at pc=%llx, fault addr=%lx, si_code=%x\n",

				((ucontext_t *)uc)->uc_mcontext.pc, addr, si->si_code);

		if ((cur_mte_cxt.trig_range >= 0 &&

		     addr >= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) &&

		     addr <= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)) ||

		     addr >= MT_CLEAR_TAGS(cur_mte_cxt.trig_addr) &&

		     addr <= (MT_CLEAR_TAGS(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)) ||

		    (cur_mte_cxt.trig_range < 0 &&

		     addr <= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) &&

		     addr >= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range))) {

		     addr <= MT_CLEAR_TAGS(cur_mte_cxt.trig_addr) &&

		     addr >= (MT_CLEAR_TAGS(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range))) {

			cur_mte_cxt.fault_valid = true;

			/* Adjust the pc by 4 */

			((ucontext_t *)uc)->uc_mcontext.pc += 4;