selftests/exec: Convert execveat test to generate KTAP output

Currently the execveat test does not produce KTAP output but rather a
custom format. This means that we only get a pass/fail for the suite, not
for each individual test that the suite does. Convert to using the standard
kselftest output functions which result in KTAP output being generated.

The main trick with this is that, being an exec() related test, the
program executes itself and returns specific exit codes to verify
success meaning that we need to only use the top level kselftest
header/summary functions when invoked directly rather than when run as
part of a test.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/exec/execveat.c

@@ -23,6 +23,9 @@
 
 #include "../kselftest.h"
 
+#define TESTS_EXPECTED 51
+#define TEST_NAME_LEN (PATH_MAX * 4)
+
 static char longpath[2 * PATH_MAX] = "";
 static char *envp[] = { "IN_TEST=yes", NULL, NULL };
 static char *argv[] = { "execveat", "99", NULL };
@@ -43,71 +46,85 @@ static int execveat_(int fd, const char *path, char **argv, char **envp,
 static int _check_execveat_fail(int fd, const char *path, int flags,
 				int expected_errno, const char *errno_str)
 {
+	char test_name[TEST_NAME_LEN];
 	int rc;
 
 	errno = 0;
-	printf("Check failure of execveat(%d, '%s', %d) with %s... ",
-		fd, path?:"(null)", flags, errno_str);
+	snprintf(test_name, sizeof(test_name),
+		 "Check failure of execveat(%d, '%s', %d) with %s",
+		 fd, path?:"(null)", flags, errno_str);
 	rc = execveat_(fd, path, argv, envp, flags);
 
 	if (rc > 0) {
-		printf("[FAIL] (unexpected success from execveat(2))\n");
+		ksft_print_msg("unexpected success from execveat(2)\n");
+		ksft_test_result_fail("%s\n", test_name);
 		return 1;
 	}
 	if (errno != expected_errno) {
-		printf("[FAIL] (expected errno %d (%s) not %d (%s)\n",
-			expected_errno, strerror(expected_errno),
-			errno, strerror(errno));
+		ksft_print_msg("expected errno %d (%s) not %d (%s)\n",
+			       expected_errno, strerror(expected_errno),
+			       errno, strerror(errno));
+		ksft_test_result_fail("%s\n", test_name);
 		return 1;
 	}
-	printf("[OK]\n");
+	ksft_test_result_pass("%s\n", test_name);
 	return 0;
 }
 
 static int check_execveat_invoked_rc(int fd, const char *path, int flags,
 				     int expected_rc, int expected_rc2)
 {
+	char test_name[TEST_NAME_LEN];
 	int status;
 	int rc;
 	pid_t child;
 	int pathlen = path ? strlen(path) : 0;
 
 	if (pathlen > 40)
-		printf("Check success of execveat(%d, '%.20s...%s', %d)... ",
-			fd, path, (path + pathlen - 20), flags);
+		snprintf(test_name, sizeof(test_name),
+			 "Check success of execveat(%d, '%.20s...%s', %d)... ",
+			 fd, path, (path + pathlen - 20), flags);
 	else
-		printf("Check success of execveat(%d, '%s', %d)... ",
-			fd, path?:"(null)", flags);
+		snprintf(test_name, sizeof(test_name),
+			 "Check success of execveat(%d, '%s', %d)... ",
+			 fd, path?:"(null)", flags);
+
 	child = fork();
 	if (child < 0) {
-		printf("[FAIL] (fork() failed)\n");
+		ksft_perror("fork() failed");
+		ksft_test_result_fail("%s\n", test_name);
 		return 1;
 	}
 	if (child == 0) {
 		/* Child: do execveat(). */
 		rc = execveat_(fd, path, argv, envp, flags);
-		printf("[FAIL]: execveat() failed, rc=%d errno=%d (%s)\n",
-			rc, errno, strerror(errno));
+		ksft_print_msg("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 */
 	}
 	/* Parent: wait for & check child's exit status. */
 	rc = waitpid(child, &status, 0);
 	if (rc != child) {
-		printf("[FAIL] (waitpid(%d,...) returned %d)\n", child, rc);
+		ksft_print_msg("waitpid(%d,...) returned %d\n", child, rc);
+		ksft_test_result_fail("%s\n", test_name);
 		return 1;
 	}
 	if (!WIFEXITED(status)) {
-		printf("[FAIL] (child %d did not exit cleanly, status=%08x)\n",
-			child, status);
+		ksft_print_msg("child %d did not exit cleanly, status=%08x\n",
+			       child, status);
+		ksft_test_result_fail("%s\n", test_name);
 		return 1;
 	}
 	if ((WEXITSTATUS(status) != expected_rc) &&
 	    (WEXITSTATUS(status) != expected_rc2)) {
-		printf("[FAIL] (child %d exited with %d not %d nor %d)\n",
-			child, WEXITSTATUS(status), expected_rc, expected_rc2);
+		ksft_print_msg("child %d exited with %d not %d nor %d\n",
+			       child, WEXITSTATUS(status), expected_rc,
+			       expected_rc2);
+		ksft_test_result_fail("%s\n", test_name);
 		return 1;
 	}
-	printf("[OK]\n");
+	ksft_test_result_pass("%s\n", test_name);
 	return 0;
 }
 
@@ -129,11 +146,9 @@ static int open_or_die(const char *filename, int flags)
 {
 	int fd = open(filename, flags);
 
-	if (fd < 0) {
-		printf("Failed to open '%s'; "
+	if (fd < 0)
+		ksft_exit_fail_msg("Failed to open '%s'; "
 			"check prerequisites are available\n", filename);
-		exit(1);
-	}
 	return fd;
 }
 
@@ -162,8 +177,7 @@ static int check_execveat_pathmax(int root_dfd, const char *src, int is_script)
 		char *cwd = getcwd(NULL, 0);
 
 		if (!cwd) {
-			printf("Failed to getcwd(), errno=%d (%s)\n",
-			       errno, strerror(errno));
+			ksft_perror("Failed to getcwd()");
 			return 2;
 		}
 		strcpy(longpath, cwd);
@@ -193,12 +207,12 @@ static int check_execveat_pathmax(int root_dfd, const char *src, int is_script)
 	 */
 	fd = open(longpath, O_RDONLY);
 	if (fd > 0) {
-		printf("Invoke copy of '%s' via filename of length %zu:\n",
-			src, strlen(longpath));
+		ksft_print_msg("Invoke copy of '%s' via filename of length %zu:\n",
+			       src, strlen(longpath));
 		fail += check_execveat(fd, "", AT_EMPTY_PATH);
 	} else {
-		printf("Failed to open length %zu filename, errno=%d (%s)\n",
-			strlen(longpath), errno, strerror(errno));
+		ksft_print_msg("Failed to open length %zu filename, errno=%d (%s)\n",
+			       strlen(longpath), errno, strerror(errno));
 		fail++;
 	}
 
@@ -405,28 +419,31 @@ int main(int argc, char **argv)
 		const char *in_test = getenv("IN_TEST");
 
 		if (verbose) {
-			printf("  invoked with:");
+			ksft_print_msg("invoked with:\n");
 			for (ii = 0; ii < argc; ii++)
-				printf(" [%d]='%s'", ii, argv[ii]);
-			printf("\n");
+				ksft_print_msg("\t[%d]='%s\n'", ii, argv[ii]);
 		}
 
 		/* Check expected environment transferred. */
 		if (!in_test || strcmp(in_test, "yes") != 0) {
-			printf("[FAIL] (no IN_TEST=yes in env)\n");
+			ksft_print_msg("no IN_TEST=yes in env\n");
 			return 1;
 		}
 
 		/* Use the final argument as an exit code. */
 		rc = atoi(argv[argc - 1]);
-		fflush(stdout);
+		exit(rc);
 	} else {
+		ksft_print_header();
+		ksft_set_plan(TESTS_EXPECTED);
 		prerequisites();
 		if (verbose)
 			envp[1] = "VERBOSE=1";
 		rc = run_tests();
 		if (rc > 0)
 			printf("%d tests failed\n", rc);
+		ksft_finished();
 	}
+
 	return rc;
 }