[PATCH] selftests/exec: execveat: Improve debug reporting

[Kees Cook <keescook@chromium.org>]

Children processes were reporting their status, duplicating the
parent's. Remove that, and add some additional details about the test
execution.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: linux-mm@kvack.org
Cc: linux-kselftest@vger.kernel.org
---
 tools/testing/selftests/exec/execveat.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/exec/execveat.c b/tools/testing/selftests/exec/execveat.c
index 0546ca24f2b2..6418ded40bdd 100644
--- a/tools/testing/selftests/exec/execveat.c
+++ b/tools/testing/selftests/exec/execveat.c
@@ -98,10 +98,9 @@ static int check_execveat_invoked_rc(int fd, const char *path, int flags,
 	if (child == 0) {
 		/* Child: do execveat(). */
 		rc = execveat_(fd, path, argv, envp, flags);
-		ksft_print_msg("execveat() failed, rc=%d errno=%d (%s)\n",
+		ksft_print_msg("child execveat() failed, rc=%d errno=%d (%s)\n",
 			       rc, errno, strerror(errno));
-		ksft_test_result_fail("%s\n", test_name);
-		exit(1);  /* should not reach here */
+		exit(errno);
 	}
 	/* Parent: wait for & check child's exit status. */
 	rc = waitpid(child, &status, 0);
@@ -226,11 +225,14 @@ static int check_execveat_pathmax(int root_dfd, const char *src, int is_script)
 	 * "If the command name is found, but it is not an executable utility,
 	 * the exit status shall be 126."), so allow either.
 	 */
-	if (is_script)
+	if (is_script) {
+		ksft_print_msg("Invoke script via root_dfd and relative filename\n");
 		fail += check_execveat_invoked_rc(root_dfd, longpath + 1, 0,
 						  127, 126);
-	else
+	} else {
+		ksft_print_msg("Invoke exec via root_dfd and relative filename\n");
 		fail += check_execveat(root_dfd, longpath + 1, 0);
+	}
 
 	return fail;
 }
-- 
2.34.1