[PATCH] selftests/x86/ptrace_syscall_32: Fix no-vDSO segfault

From: Andy Lutomirski
Date: Thu Mar 12 2020 - 18:35:54 EST


If AT_SYSINFO is not present, don't try to call a NULL pointer.

Reported-by: kbuild test robot <lkp@xxxxxxxxx>
Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
tools/testing/selftests/x86/ptrace_syscall.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/x86/ptrace_syscall.c b/tools/testing/selftests/x86/ptrace_syscall.c
index 6f22238f3217..12aaa063196e 100644
--- a/tools/testing/selftests/x86/ptrace_syscall.c
+++ b/tools/testing/selftests/x86/ptrace_syscall.c
@@ -414,8 +414,12 @@ int main()

#if defined(__i386__) && (!defined(__GLIBC__) || __GLIBC__ > 2 || __GLIBC_MINOR__ >= 16)
vsyscall32 = (void *)getauxval(AT_SYSINFO);
- printf("[RUN]\tCheck AT_SYSINFO return regs\n");
- test_sys32_regs(do_full_vsyscall32);
+ if (vsyscall32) {
+ printf("[RUN]\tCheck AT_SYSINFO return regs\n");
+ test_sys32_regs(do_full_vsyscall32);
+ } else {
+ printf("[SKIP]\tAT_SYSINFO is not available\n");
+ }
#endif

test_ptrace_syscall_restart();
--
2.24.1