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| author |   Chang S. Bae <chang.seok.bae@intel.com> | 2021-05-18 13:03:18 -0700 |
|---|---|---|
| committer |   Borislav Petkov <bp@suse.de> | 2021-05-19 12:38:17 +0200 |
| commit | bdf6c8b84a4fa726c382ef6d3518f3ae123a7ebd (patch) | |
| tree | 748bb858c73b77862f456afb8ab881613ebebac5 | |
| parent | x86/elf: Support a new ELF aux vector AT_MINSIGSTKSZ (diff) | |
| download | linux-dev-bdf6c8b84a4fa726c382ef6d3518f3ae123a7ebd.tar.xz linux-dev-bdf6c8b84a4fa726c382ef6d3518f3ae123a7ebd.zip | |
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@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Len Brown <len.brown@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20210518200320.17239-5-chang.seok.bae@intel.com
| -rw-r--r-- | tools/testing/selftests/sigaltstack/sas.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/tools/testing/selftests/sigaltstack/sas.c b/tools/testing/selftests/sigaltstack/sas.c index 8934a3766d20..c53b070755b6 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); |