The following commit has been merged into the x86/fpu branch of tip:
Commit-ID: bdf6c8b84a4fa726c382ef6d3518f3ae123a7ebd
Gitweb: https://git.kernel.org/tip/bdf6c8b84a4fa726c382ef6d3518f3ae123a7ebd
Author: Chang S. Bae <chang.seok.bae@xxxxxxxxx>
AuthorDate: Tue, 18 May 2021 13:03:18 -07:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Wed, 19 May 2021 12:38:17 +02:00
selftest/sigaltstack: Use the AT_MINSIGSTKSZ aux vector if available
The SIGSTKSZ constant may not represent enough stack size in some
architectures as the hardware state size grows.
Use getauxval(AT_MINSIGSTKSZ) to increase the stack size.
Signed-off-by: Chang S. Bae <chang.seok.bae@xxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Len Brown <len.brown@xxxxxxxxx>
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20210518200320.17239-5-chang.seok.bae@xxxxxxxxx
---
tools/testing/selftests/sigaltstack/sas.c | 20 +++++++++++++++-----
1 file changed, 15 insertions(+), 5 deletions(-)
diff --git a/tools/testing/selftests/sigaltstack/sas.c b/tools/testing/selftests/sigaltstack/sas.c
index 8934a37..c53b070 100644
--- a/tools/testing/selftests/sigaltstack/sas.c
+++ b/tools/testing/selftests/sigaltstack/sas.c
@@ -17,6 +17,7 @@
#include <string.h>
#include <assert.h>
#include <errno.h>
+#include <sys/auxv.h>
#include "../kselftest.h"
@@ -24,6 +25,11 @@
#define SS_AUTODISARM (1U << 31)
#endif
+#ifndef AT_MINSIGSTKSZ
+#define AT_MINSIGSTKSZ 51
+#endif
+
+static unsigned int stack_size;
static void *sstack, *ustack;
static ucontext_t uc, sc;
static const char *msg = "[OK]\tStack preserved";
@@ -47,7 +53,7 @@ void my_usr1(int sig, siginfo_t *si, void *u)
#endif
if (sp < (unsigned long)sstack ||
- sp >= (unsigned long)sstack + SIGSTKSZ) {
+ sp >= (unsigned long)sstack + stack_size) {
ksft_exit_fail_msg("SP is not on sigaltstack\n");
}
/* put some data on stack. other sighandler will try to overwrite it */
@@ -108,6 +114,10 @@ int main(void)
stack_t stk;
int err;
+ /* Make sure more than the required minimum. */
+ stack_size = getauxval(AT_MINSIGSTKSZ) + SIGSTKSZ;
+ ksft_print_msg("[NOTE]\tthe stack size is %lu\n", stack_size);
+
ksft_print_header();
ksft_set_plan(3);
@@ -117,7 +127,7 @@ int main(void)
sigaction(SIGUSR1, &act, NULL);
act.sa_sigaction = my_usr2;
sigaction(SIGUSR2, &act, NULL);
- sstack = mmap(NULL, SIGSTKSZ, PROT_READ | PROT_WRITE,
+ sstack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0);
if (sstack == MAP_FAILED) {
ksft_exit_fail_msg("mmap() - %s\n", strerror(errno));
@@ -139,7 +149,7 @@ int main(void)
}
stk.ss_sp = sstack;
- stk.ss_size = SIGSTKSZ;
+ stk.ss_size = stack_size;
stk.ss_flags = SS_ONSTACK | SS_AUTODISARM;
err = sigaltstack(&stk, NULL);
if (err) {
@@ -161,7 +171,7 @@ int main(void)
}
}
- ustack = mmap(NULL, SIGSTKSZ, PROT_READ | PROT_WRITE,
+ ustack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0);
if (ustack == MAP_FAILED) {
ksft_exit_fail_msg("mmap() - %s\n", strerror(errno));
@@ -170,7 +180,7 @@ int main(void)
getcontext(&uc);
uc.uc_link = NULL;
uc.uc_stack.ss_sp = ustack;
- uc.uc_stack.ss_size = SIGSTKSZ;
+ uc.uc_stack.ss_size = stack_size;
makecontext(&uc, switch_fn, 0);
raise(SIGUSR1);
|