Commit 922a1b52 authored by Sargun Dhillon's avatar Sargun Dhillon Committed by Kees Cook
Browse files

selftests/seccomp: Refactor get_proc_stat to split out file reading code 



This splits up the get_proc_stat function to make it so we can use it as a
generic helper to read the nth field from multiple different files, versus
replicating the logic in multiple places.

Signed-off-by: default avatarSargun Dhillon <sargun@sargun.me>
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220503080958.20220-3-sargun@sargun.me
parent c2aa2dfe

tools/testing/selftests/seccomp/seccomp_bpf.c

+38 −16
Original line number Diff line number Diff line
@@ -4297,32 +4297,54 @@ TEST_F(O_SUSPEND_SECCOMP, seize) 
	ASSERT_EQ(EPERM, errno);

}



static char get_proc_stat(int pid)

/*

 * get_nth - Get the nth, space separated entry in a file.

 *

 * Returns the length of the read field.

 * Throws error if field is zero-lengthed.

 */

static ssize_t get_nth(struct __test_metadata *_metadata, const char *path,

		     const unsigned int position, char **entry)

{

	char proc_path[100] = {0};

	char *line = NULL;

	size_t len = 0;

	unsigned int i;

	ssize_t nread;

	char status;

	size_t len = 0;

	FILE *f;

	int i;



	snprintf(proc_path, sizeof(proc_path), "/proc/%d/stat", pid);

	f = fopen(proc_path, "r");

	if (f == NULL)

		ksft_exit_fail_msg("%s - Could not open %s\n",

				   strerror(errno), proc_path);

	f = fopen(path, "r");

	ASSERT_NE(f, NULL) {

		TH_LOG("Coud not open %s: %s", path, strerror(errno));

	}



	for (i = 0; i < 3; i++) {

	for (i = 0; i < position; i++) {

		nread = getdelim(&line, &len, ' ', f);

		if (nread <= 0)

			ksft_exit_fail_msg("Failed to read status: %s\n",

					   strerror(errno));

		ASSERT_GE(nread, 0) {

			TH_LOG("Failed to read %d entry in file %s", i, path);

		}

	}

	fclose(f);



	ASSERT_GT(nread, 0) {

		TH_LOG("Entry in file %s had zero length", path);

	}



	*entry = line;

	return nread - 1;

}



/* For a given PID, get the task state (D, R, etc...) */

static char get_proc_stat(struct __test_metadata *_metadata, pid_t pid)

{

	char proc_path[100] = {0};

	char status;

	char *line;



	snprintf(proc_path, sizeof(proc_path), "/proc/%d/stat", pid);

	ASSERT_EQ(get_nth(_metadata, proc_path, 3, &line), 1);



	status = *line;

	free(line);

	fclose(f);



	return status;

}
@@ -4383,7 +4405,7 @@ TEST(user_notification_fifo) 
	/* This spins until all of the children are sleeping */

restart_wait:

	for (i = 0; i < ARRAY_SIZE(pids); i++) {

		if (get_proc_stat(pids[i]) != 'S') {

		if (get_proc_stat(_metadata, pids[i]) != 'S') {

			nanosleep(&delay, NULL);

			goto restart_wait;

		}