[PATCH] kselftest: Fix vdso_test_abi return status

[Vincenzo Frascino <vincenzo.frascino@xxxxxxx>]

vdso_test_abi contains a batch of tests that verify the validity of the
vDSO ABI.

When a vDSO symbol is not found the relevant test is skipped reporting
KSFT_SKIP. All the tests return values are then added in a single
variable which is checked to verify failures. This approach can have
side effects which result in reporting the wrong kselftest exit status.

Fix vdso_test_abi verifying the return code of each test separately.

Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reported-by: Cristian Marussi <cristian.marussi@xxxxxxx>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
---
 tools/testing/selftests/vDSO/vdso_test_abi.c | 27 +++++++++++---------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/tools/testing/selftests/vDSO/vdso_test_abi.c b/tools/testing/selftests/vDSO/vdso_test_abi.c
index 3d603f1394af..3a4efb91b9b2 100644
--- a/tools/testing/selftests/vDSO/vdso_test_abi.c
+++ b/tools/testing/selftests/vDSO/vdso_test_abi.c
@@ -184,10 +184,12 @@ static inline int vdso_test_clock(clockid_t clock_id)
 	return ret0;
 }
 
+#define VDSO_TESTS_MAX	9
+
 int main(int argc, char **argv)
 {
 	unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
-	int ret;
+	int ret[VDSO_TESTS_MAX] = {0};
 
 	if (!sysinfo_ehdr) {
 		printf("AT_SYSINFO_EHDR is not present!\n");
@@ -201,44 +203,45 @@ int main(int argc, char **argv)
 
 	vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR));
 
-	ret = vdso_test_gettimeofday();
+	ret[0] = vdso_test_gettimeofday();
 
 #if _POSIX_TIMERS > 0
 
 #ifdef CLOCK_REALTIME
-	ret += vdso_test_clock(CLOCK_REALTIME);
+	ret[1] = vdso_test_clock(CLOCK_REALTIME);
 #endif
 
 #ifdef CLOCK_BOOTTIME
-	ret += vdso_test_clock(CLOCK_BOOTTIME);
+	ret[2] = vdso_test_clock(CLOCK_BOOTTIME);
 #endif
 
 #ifdef CLOCK_TAI
-	ret += vdso_test_clock(CLOCK_TAI);
+	ret[3] = vdso_test_clock(CLOCK_TAI);
 #endif
 
 #ifdef CLOCK_REALTIME_COARSE
-	ret += vdso_test_clock(CLOCK_REALTIME_COARSE);
+	ret[4] = vdso_test_clock(CLOCK_REALTIME_COARSE);
 #endif
 
 #ifdef CLOCK_MONOTONIC
-	ret += vdso_test_clock(CLOCK_MONOTONIC);
+	ret[5] = vdso_test_clock(CLOCK_MONOTONIC);
 #endif
 
 #ifdef CLOCK_MONOTONIC_RAW
-	ret += vdso_test_clock(CLOCK_MONOTONIC_RAW);
+	ret[6] = vdso_test_clock(CLOCK_MONOTONIC_RAW);
 #endif
 
 #ifdef CLOCK_MONOTONIC_COARSE
-	ret += vdso_test_clock(CLOCK_MONOTONIC_COARSE);
+	ret[7] = vdso_test_clock(CLOCK_MONOTONIC_COARSE);
 #endif
 
 #endif
 
-	ret += vdso_test_time();
+	ret[8] = vdso_test_time();
 
-	if (ret > 0)
-		return KSFT_FAIL;
+	for (int i = 0; i < VDSO_TESTS_MAX; i++)
+		if (ret[i] == KSFT_FAIL)
+			return KSFT_FAIL;
 
 	return KSFT_PASS;
 }
-- 
2.34.1