Unverified Commit 474dd09d authored by Christian Brauner's avatar Christian Brauner
Browse files

selftests/coredump: cleanup coredump tests 

Make the selftests we added this cycle easier to read.

Link: https://lore.kernel.org/20250603-work-coredump-socket-protocol-v2-3-05a5f0c18ecc@kernel.org


Acked-by: default avatarLennart Poettering <lennart@poettering.net>
Reviewed-by: default avatarAlexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 994dc263

tools/testing/selftests/coredump/stackdump_test.c

+174 −235
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



#include <assert.h>

#include <fcntl.h>

#include <inttypes.h>

#include <libgen.h>
@@ -20,6 +21,10 @@ 
#define STACKDUMP_SCRIPT "stackdump"

#define NUM_THREAD_SPAWN 128



#ifndef PAGE_SIZE

#define PAGE_SIZE 4096

#endif



static void *do_nothing(void *)

{

	while (1)
@@ -109,7 +114,7 @@ TEST_F_TIMEOUT(coredump, stackdump, 120) 
	unsigned long long stack;

	char *test_dir, *line;

	size_t line_length;

	char buf[PATH_MAX];

	char buf[PAGE_SIZE];

	int ret, i, status;

	FILE *file;

	pid_t pid;
@@ -168,152 +173,163 @@ TEST_F_TIMEOUT(coredump, stackdump, 120) 
	fclose(file);

}



static int create_and_listen_unix_socket(const char *path)

{

	struct sockaddr_un addr = {

		.sun_family = AF_UNIX,

	};

	assert(strlen(path) < sizeof(addr.sun_path) - 1);

	strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);

	size_t addr_len =

		offsetof(struct sockaddr_un, sun_path) + strlen(path) + 1;

	int fd, ret;



	fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0);

	if (fd < 0)

		goto out;



	ret = bind(fd, (const struct sockaddr *)&addr, addr_len);

	if (ret < 0)

		goto out;



	ret = listen(fd, 1);

	if (ret < 0)

		goto out;



	return fd;



out:

	if (fd >= 0)

		close(fd);

	return -1;

}



static bool set_core_pattern(const char *pattern)

{

	FILE *file;

	int ret;



	file = fopen("/proc/sys/kernel/core_pattern", "w");

	if (!file)

		return false;



	ret = fprintf(file, "%s", pattern);

	fclose(file);



	return ret == strlen(pattern);

}



static int get_peer_pidfd(int fd)

{

	int fd_peer_pidfd;

	socklen_t fd_peer_pidfd_len = sizeof(fd_peer_pidfd);

	int ret = getsockopt(fd, SOL_SOCKET, SO_PEERPIDFD, &fd_peer_pidfd,

			     &fd_peer_pidfd_len);

	if (ret < 0) {

		fprintf(stderr, "%m - Failed to retrieve peer pidfd for coredump socket connection\n");

		return -1;

	}

	return fd_peer_pidfd;

}



static bool get_pidfd_info(int fd_peer_pidfd, struct pidfd_info *info)

{

	memset(info, 0, sizeof(*info));

	info->mask = PIDFD_INFO_EXIT | PIDFD_INFO_COREDUMP;

	return ioctl(fd_peer_pidfd, PIDFD_GET_INFO, info) == 0;

}



static void

wait_and_check_coredump_server(pid_t pid_coredump_server,

			       struct __test_metadata *const _metadata,

			       FIXTURE_DATA(coredump)* self)

{

	int status;

	waitpid(pid_coredump_server, &status, 0);

	self->pid_coredump_server = -ESRCH;

	ASSERT_TRUE(WIFEXITED(status));

	ASSERT_EQ(WEXITSTATUS(status), 0);

}



TEST_F(coredump, socket)

{

	int pidfd, ret, status;

	FILE *file;

	pid_t pid, pid_coredump_server;

	struct stat st;

	struct pidfd_info info = {};

	int ipc_sockets[2];

	char c;

	const struct sockaddr_un coredump_sk = {

		.sun_family = AF_UNIX,

		.sun_path = "/tmp/coredump.socket",

	};

	size_t coredump_sk_len = offsetof(struct sockaddr_un, sun_path) +

				 sizeof("/tmp/coredump.socket");



	ASSERT_TRUE(set_core_pattern("@/tmp/coredump.socket"));



	ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets);

	ASSERT_EQ(ret, 0);



	file = fopen("/proc/sys/kernel/core_pattern", "w");

	ASSERT_NE(file, NULL);



	ret = fprintf(file, "@/tmp/coredump.socket");

	ASSERT_EQ(ret, strlen("@/tmp/coredump.socket"));

	ASSERT_EQ(fclose(file), 0);



	pid_coredump_server = fork();

	ASSERT_GE(pid_coredump_server, 0);

	if (pid_coredump_server == 0) {

		int fd_server, fd_coredump, fd_peer_pidfd, fd_core_file;

		socklen_t fd_peer_pidfd_len;

		int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1, fd_core_file = -1;

		int exit_code = EXIT_FAILURE;



		close(ipc_sockets[0]);



		fd_server = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0);

		fd_server = create_and_listen_unix_socket("/tmp/coredump.socket");

		if (fd_server < 0)

			_exit(EXIT_FAILURE);

			goto out;



		ret = bind(fd_server, (const struct sockaddr *)&coredump_sk, coredump_sk_len);

		if (ret < 0) {

			fprintf(stderr, "Failed to bind coredump socket\n");

			close(fd_server);

			close(ipc_sockets[1]);

			_exit(EXIT_FAILURE);

		}



		ret = listen(fd_server, 1);

		if (ret < 0) {

			fprintf(stderr, "Failed to listen on coredump socket\n");

			close(fd_server);

			close(ipc_sockets[1]);

			_exit(EXIT_FAILURE);

		}



		if (write_nointr(ipc_sockets[1], "1", 1) < 0) {

			close(fd_server);

			close(ipc_sockets[1]);

			_exit(EXIT_FAILURE);

		}

		if (write_nointr(ipc_sockets[1], "1", 1) < 0)

			goto out;



		close(ipc_sockets[1]);



		fd_coredump = accept4(fd_server, NULL, NULL, SOCK_CLOEXEC);

		if (fd_coredump < 0) {

			fprintf(stderr, "Failed to accept coredump socket connection\n");

			close(fd_server);

			_exit(EXIT_FAILURE);

		}

		if (fd_coredump < 0)

			goto out;



		fd_peer_pidfd_len = sizeof(fd_peer_pidfd);

		ret = getsockopt(fd_coredump, SOL_SOCKET, SO_PEERPIDFD,

				 &fd_peer_pidfd, &fd_peer_pidfd_len);

		if (ret < 0) {

			fprintf(stderr, "%m - Failed to retrieve peer pidfd for coredump socket connection\n");

			close(fd_coredump);

			close(fd_server);

			_exit(EXIT_FAILURE);

		}

		fd_peer_pidfd = get_peer_pidfd(fd_coredump);

		if (fd_peer_pidfd < 0)

			goto out;



		memset(&info, 0, sizeof(info));

		info.mask = PIDFD_INFO_EXIT | PIDFD_INFO_COREDUMP;

		ret = ioctl(fd_peer_pidfd, PIDFD_GET_INFO, &info);

		if (ret < 0) {

			fprintf(stderr, "Failed to retrieve pidfd info from peer pidfd for coredump socket connection\n");

			close(fd_coredump);

			close(fd_server);

			close(fd_peer_pidfd);

			_exit(EXIT_FAILURE);

		}

		if (!get_pidfd_info(fd_peer_pidfd, &info))

			goto out;



		if (!(info.mask & PIDFD_INFO_COREDUMP)) {

			fprintf(stderr, "Missing coredump information from coredumping task\n");

			close(fd_coredump);

			close(fd_server);

			close(fd_peer_pidfd);

			_exit(EXIT_FAILURE);

		}

		if (!(info.mask & PIDFD_INFO_COREDUMP))

			goto out;



		if (!(info.coredump_mask & PIDFD_COREDUMPED)) {

			fprintf(stderr, "Received connection from non-coredumping task\n");

			close(fd_coredump);

			close(fd_server);

			close(fd_peer_pidfd);

			_exit(EXIT_FAILURE);

		}

		if (!(info.coredump_mask & PIDFD_COREDUMPED))

			goto out;



		fd_core_file = creat("/tmp/coredump.file", 0644);

		if (fd_core_file < 0) {

			fprintf(stderr, "Failed to create coredump file\n");

			close(fd_coredump);

			close(fd_server);

			close(fd_peer_pidfd);

			_exit(EXIT_FAILURE);

		}

		if (fd_core_file < 0)

			goto out;



		for (;;) {

			char buffer[4096];

			ssize_t bytes_read, bytes_write;



			bytes_read = read(fd_coredump, buffer, sizeof(buffer));

			if (bytes_read < 0) {

				close(fd_coredump);

				close(fd_server);

				close(fd_peer_pidfd);

				close(fd_core_file);

				_exit(EXIT_FAILURE);

			}

			if (bytes_read < 0)

				goto out;



			if (bytes_read == 0)

				break;



			bytes_write = write(fd_core_file, buffer, bytes_read);

			if (bytes_read != bytes_write) {

				close(fd_coredump);

				close(fd_server);

				close(fd_peer_pidfd);

				close(fd_core_file);

				_exit(EXIT_FAILURE);

			}

			if (bytes_read != bytes_write)

				goto out;

		}



		exit_code = EXIT_SUCCESS;

out:

		if (fd_core_file >= 0)

			close(fd_core_file);

		if (fd_peer_pidfd >= 0)

			close(fd_peer_pidfd);

		if (fd_coredump >= 0)

			close(fd_coredump);

		if (fd_server >= 0)

			close(fd_server);

		close(fd_peer_pidfd);

		close(fd_core_file);

		_exit(EXIT_SUCCESS);

		_exit(exit_code);

	}

	self->pid_coredump_server = pid_coredump_server;
@@ -333,47 +349,27 @@ TEST_F(coredump, socket) 
	ASSERT_TRUE(WIFSIGNALED(status));

	ASSERT_TRUE(WCOREDUMP(status));



	info.mask = PIDFD_INFO_EXIT | PIDFD_INFO_COREDUMP;

	ASSERT_EQ(ioctl(pidfd, PIDFD_GET_INFO, &info), 0);

	ASSERT_TRUE(get_pidfd_info(pidfd, &info));

	ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0);

	ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0);



	waitpid(pid_coredump_server, &status, 0);

	self->pid_coredump_server = -ESRCH;

	ASSERT_TRUE(WIFEXITED(status));

	ASSERT_EQ(WEXITSTATUS(status), 0);

	wait_and_check_coredump_server(pid_coredump_server, _metadata, self);



	ASSERT_EQ(stat("/tmp/coredump.file", &st), 0);

	ASSERT_GT(st.st_size, 0);

	/*

	 * We should somehow validate the produced core file.

	 * For now just allow for visual inspection

	 */

	system("file /tmp/coredump.file");

}



TEST_F(coredump, socket_detect_userspace_client)

{

	int pidfd, ret, status;

	FILE *file;

	pid_t pid, pid_coredump_server;

	struct stat st;

	struct pidfd_info info = {};

	int ipc_sockets[2];

	char c;

	const struct sockaddr_un coredump_sk = {

		.sun_family = AF_UNIX,

		.sun_path = "/tmp/coredump.socket",

	};

	size_t coredump_sk_len = offsetof(struct sockaddr_un, sun_path) +

				 sizeof("/tmp/coredump.socket");



	file = fopen("/proc/sys/kernel/core_pattern", "w");

	ASSERT_NE(file, NULL);



	ret = fprintf(file, "@/tmp/coredump.socket");

	ASSERT_EQ(ret, strlen("@/tmp/coredump.socket"));

	ASSERT_EQ(fclose(file), 0);

	ASSERT_TRUE(set_core_pattern("@/tmp/coredump.socket"));



	ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets);

	ASSERT_EQ(ret, 0);
@@ -381,87 +377,46 @@ TEST_F(coredump, socket_detect_userspace_client) 
	pid_coredump_server = fork();

	ASSERT_GE(pid_coredump_server, 0);

	if (pid_coredump_server == 0) {

		int fd_server, fd_coredump, fd_peer_pidfd;

		socklen_t fd_peer_pidfd_len;

		int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1;

		int exit_code = EXIT_FAILURE;



		close(ipc_sockets[0]);



		fd_server = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0);

		fd_server = create_and_listen_unix_socket("/tmp/coredump.socket");

		if (fd_server < 0)

			_exit(EXIT_FAILURE);



		ret = bind(fd_server, (const struct sockaddr *)&coredump_sk, coredump_sk_len);

		if (ret < 0) {

			fprintf(stderr, "Failed to bind coredump socket\n");

			close(fd_server);

			close(ipc_sockets[1]);

			_exit(EXIT_FAILURE);

		}

			goto out;



		ret = listen(fd_server, 1);

		if (ret < 0) {

			fprintf(stderr, "Failed to listen on coredump socket\n");

			close(fd_server);

			close(ipc_sockets[1]);

			_exit(EXIT_FAILURE);

		}



		if (write_nointr(ipc_sockets[1], "1", 1) < 0) {

			close(fd_server);

			close(ipc_sockets[1]);

			_exit(EXIT_FAILURE);

		}

		if (write_nointr(ipc_sockets[1], "1", 1) < 0)

			goto out;



		close(ipc_sockets[1]);



		fd_coredump = accept4(fd_server, NULL, NULL, SOCK_CLOEXEC);

		if (fd_coredump < 0) {

			fprintf(stderr, "Failed to accept coredump socket connection\n");

			close(fd_server);

			_exit(EXIT_FAILURE);

		}

		if (fd_coredump < 0)

			goto out;



		fd_peer_pidfd_len = sizeof(fd_peer_pidfd);

		ret = getsockopt(fd_coredump, SOL_SOCKET, SO_PEERPIDFD,

				 &fd_peer_pidfd, &fd_peer_pidfd_len);

		if (ret < 0) {

			fprintf(stderr, "%m - Failed to retrieve peer pidfd for coredump socket connection\n");

			close(fd_coredump);

			close(fd_server);

			_exit(EXIT_FAILURE);

		}

		fd_peer_pidfd = get_peer_pidfd(fd_coredump);

		if (fd_peer_pidfd < 0)

			goto out;



		memset(&info, 0, sizeof(info));

		info.mask = PIDFD_INFO_EXIT | PIDFD_INFO_COREDUMP;

		ret = ioctl(fd_peer_pidfd, PIDFD_GET_INFO, &info);

		if (ret < 0) {

			fprintf(stderr, "Failed to retrieve pidfd info from peer pidfd for coredump socket connection\n");

			close(fd_coredump);

			close(fd_server);

			close(fd_peer_pidfd);

			_exit(EXIT_FAILURE);

		}

		if (!get_pidfd_info(fd_peer_pidfd, &info))

			goto out;



		if (!(info.mask & PIDFD_INFO_COREDUMP)) {

			fprintf(stderr, "Missing coredump information from coredumping task\n");

			close(fd_coredump);

			close(fd_server);

			close(fd_peer_pidfd);

			_exit(EXIT_FAILURE);

		}

		if (!(info.mask & PIDFD_INFO_COREDUMP))

			goto out;



		if (info.coredump_mask & PIDFD_COREDUMPED) {

			fprintf(stderr, "Received unexpected connection from coredumping task\n");

			close(fd_coredump);

			close(fd_server);

			close(fd_peer_pidfd);

			_exit(EXIT_FAILURE);

		}

		if (info.coredump_mask & PIDFD_COREDUMPED)

			goto out;



		exit_code = EXIT_SUCCESS;

out:

		if (fd_peer_pidfd >= 0)

			close(fd_peer_pidfd);

		if (fd_coredump >= 0)

			close(fd_coredump);

		if (fd_server >= 0)

			close(fd_server);

		close(fd_peer_pidfd);

		_exit(EXIT_SUCCESS);

		_exit(exit_code);

	}

	self->pid_coredump_server = pid_coredump_server;
@@ -474,12 +429,18 @@ TEST_F(coredump, socket_detect_userspace_client) 
	if (pid == 0) {

		int fd_socket;

		ssize_t ret;

		const struct sockaddr_un coredump_sk = {

			.sun_family = AF_UNIX,

			.sun_path = "/tmp/coredump.socket",

		};

		size_t coredump_sk_len =

			offsetof(struct sockaddr_un, sun_path) +

			sizeof("/tmp/coredump.socket");



		fd_socket = socket(AF_UNIX, SOCK_STREAM, 0);

		if (fd_socket < 0)

			_exit(EXIT_FAILURE);





		ret = connect(fd_socket, (const struct sockaddr *)&coredump_sk, coredump_sk_len);

		if (ret < 0)

			_exit(EXIT_FAILURE);
@@ -495,15 +456,11 @@ TEST_F(coredump, socket_detect_userspace_client) 
	ASSERT_TRUE(WIFEXITED(status));

	ASSERT_EQ(WEXITSTATUS(status), 0);



	info.mask = PIDFD_INFO_EXIT | PIDFD_INFO_COREDUMP;

	ASSERT_EQ(ioctl(pidfd, PIDFD_GET_INFO, &info), 0);

	ASSERT_TRUE(get_pidfd_info(pidfd, &info));

	ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0);

	ASSERT_EQ((info.coredump_mask & PIDFD_COREDUMPED), 0);



	waitpid(pid_coredump_server, &status, 0);

	self->pid_coredump_server = -ESRCH;

	ASSERT_TRUE(WIFEXITED(status));

	ASSERT_EQ(WEXITSTATUS(status), 0);

	wait_and_check_coredump_server(pid_coredump_server, _metadata, self);



	ASSERT_NE(stat("/tmp/coredump.file", &st), 0);

	ASSERT_EQ(errno, ENOENT);
@@ -511,16 +468,10 @@ TEST_F(coredump, socket_detect_userspace_client) 


TEST_F(coredump, socket_enoent)

{

	int pidfd, ret, status;

	FILE *file;

	int pidfd, status;

	pid_t pid;



	file = fopen("/proc/sys/kernel/core_pattern", "w");

	ASSERT_NE(file, NULL);



	ret = fprintf(file, "@/tmp/coredump.socket");

	ASSERT_EQ(ret, strlen("@/tmp/coredump.socket"));

	ASSERT_EQ(fclose(file), 0);

	ASSERT_TRUE(set_core_pattern("@/tmp/coredump.socket"));



	pid = fork();

	ASSERT_GE(pid, 0);
@@ -538,7 +489,6 @@ TEST_F(coredump, socket_enoent) 
TEST_F(coredump, socket_no_listener)

{

	int pidfd, ret, status;

	FILE *file;

	pid_t pid, pid_coredump_server;

	int ipc_sockets[2];

	char c;
@@ -549,44 +499,36 @@ TEST_F(coredump, socket_no_listener) 
	size_t coredump_sk_len = offsetof(struct sockaddr_un, sun_path) +

				 sizeof("/tmp/coredump.socket");



	ASSERT_TRUE(set_core_pattern("@/tmp/coredump.socket"));



	ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets);

	ASSERT_EQ(ret, 0);



	file = fopen("/proc/sys/kernel/core_pattern", "w");

	ASSERT_NE(file, NULL);



	ret = fprintf(file, "@/tmp/coredump.socket");

	ASSERT_EQ(ret, strlen("@/tmp/coredump.socket"));

	ASSERT_EQ(fclose(file), 0);



	pid_coredump_server = fork();

	ASSERT_GE(pid_coredump_server, 0);

	if (pid_coredump_server == 0) {

		int fd_server;

		int fd_server = -1;

		int exit_code = EXIT_FAILURE;



		close(ipc_sockets[0]);



		fd_server = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0);

		if (fd_server < 0)

			_exit(EXIT_FAILURE);

			goto out;



		ret = bind(fd_server, (const struct sockaddr *)&coredump_sk, coredump_sk_len);

		if (ret < 0) {

			fprintf(stderr, "Failed to bind coredump socket\n");

			close(fd_server);

			close(ipc_sockets[1]);

			_exit(EXIT_FAILURE);

		}

		if (ret < 0)

			goto out;



		if (write_nointr(ipc_sockets[1], "1", 1) < 0) {

			close(fd_server);

			close(ipc_sockets[1]);

			_exit(EXIT_FAILURE);

		}

		if (write_nointr(ipc_sockets[1], "1", 1) < 0)

			goto out;



		exit_code = EXIT_SUCCESS;

out:

		if (fd_server >= 0)

			close(fd_server);

		close(ipc_sockets[1]);

		_exit(EXIT_SUCCESS);

		_exit(exit_code);

	}

	self->pid_coredump_server = pid_coredump_server;
@@ -606,10 +548,7 @@ TEST_F(coredump, socket_no_listener) 
	ASSERT_TRUE(WIFSIGNALED(status));

	ASSERT_FALSE(WCOREDUMP(status));



	waitpid(pid_coredump_server, &status, 0);

	self->pid_coredump_server = -ESRCH;

	ASSERT_TRUE(WIFEXITED(status));

	ASSERT_EQ(WEXITSTATUS(status), 0);

	wait_and_check_coredump_server(pid_coredump_server, _metadata, self);

}



TEST_HARNESS_MAIN