diff options
Diffstat (limited to 'tools/testing/selftests/coredump')
| -rw-r--r-- | tools/testing/selftests/coredump/Makefile | 7 | ||||
| -rw-r--r-- | tools/testing/selftests/coredump/README.rst | 50 | ||||
| -rw-r--r-- | tools/testing/selftests/coredump/config | 3 | ||||
| -rwxr-xr-x | tools/testing/selftests/coredump/stackdump | 14 | ||||
| -rw-r--r-- | tools/testing/selftests/coredump/stackdump_test.c | 1830 |
5 files changed, 1904 insertions, 0 deletions
diff --git a/tools/testing/selftests/coredump/Makefile b/tools/testing/selftests/coredump/Makefile new file mode 100644 index 000000000000..77b3665c73c7 --- /dev/null +++ b/tools/testing/selftests/coredump/Makefile @@ -0,0 +1,7 @@ +# SPDX-License-Identifier: GPL-2.0-only +CFLAGS += -Wall -O0 -g $(KHDR_INCLUDES) $(TOOLS_INCLUDES) + +TEST_GEN_PROGS := stackdump_test +TEST_FILES := stackdump + +include ../lib.mk diff --git a/tools/testing/selftests/coredump/README.rst b/tools/testing/selftests/coredump/README.rst new file mode 100644 index 000000000000..164a7aa181c8 --- /dev/null +++ b/tools/testing/selftests/coredump/README.rst @@ -0,0 +1,50 @@ +coredump selftest +================= + +Background context +------------------ + +`coredump` is a feature which dumps a process's memory space when the process terminates +unexpectedly (e.g. due to segmentation fault), which can be useful for debugging. By default, +`coredump` dumps the memory to the file named `core`, but this behavior can be changed by writing a +different file name to `/proc/sys/kernel/core_pattern`. Furthermore, `coredump` can be piped to a +user-space program by writing the pipe symbol (`|`) followed by the command to be executed to +`/proc/sys/kernel/core_pattern`. For the full description, see `man 5 core`. + +The piped user program may be interested in reading the stack pointers of the crashed process. The +crashed process's stack pointers can be read from `procfs`: it is the `kstkesp` field in +`/proc/$PID/stat`. See `man 5 proc` for all the details. + +The problem +----------- +While a thread is active, the stack pointer is unsafe to read and therefore the `kstkesp` field +reads zero. But when the thread is dead (e.g. during a coredump), this field should have valid +value. + +However, this was broken in the past and `kstkesp` was zero even during coredump: + +* commit 0a1eb2d474ed ("fs/proc: Stop reporting eip and esp in /proc/PID/stat") changed kstkesp to + always be zero + +* commit fd7d56270b52 ("fs/proc: Report eip/esp in /prod/PID/stat for coredumping") fixed it for the + coredumping thread. However, other threads in a coredumping process still had the problem. + +* commit cb8f381f1613 ("fs/proc/array.c: allow reporting eip/esp for all coredumping threads") fixed + for all threads in a coredumping process. + +* commit 92307383082d ("coredump: Don't perform any cleanups before dumping core") broke it again + for the other threads in a coredumping process. + +The problem has been fixed now, but considering the history, it may appear again in the future. + +The goal of this test +--------------------- +This test detects problem with reading `kstkesp` during coredump by doing the following: + +#. Tell the kernel to execute the "stackdump" script when a coredump happens. This script + reads the stack pointers of all threads of crashed processes. + +#. Spawn a child process who creates some threads and then crashes. + +#. Read the output from the "stackdump" script, and make sure all stack pointer values are + non-zero. diff --git a/tools/testing/selftests/coredump/config b/tools/testing/selftests/coredump/config new file mode 100644 index 000000000000..a05ef112b4f9 --- /dev/null +++ b/tools/testing/selftests/coredump/config @@ -0,0 +1,3 @@ +CONFIG_COREDUMP=y +CONFIG_NET=y +CONFIG_UNIX=y diff --git a/tools/testing/selftests/coredump/stackdump b/tools/testing/selftests/coredump/stackdump new file mode 100755 index 000000000000..96714ce42d12 --- /dev/null +++ b/tools/testing/selftests/coredump/stackdump @@ -0,0 +1,14 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 + +CRASH_PROGRAM_ID=$1 +STACKDUMP_FILE=$2 + +TMP=$(mktemp) + +for t in /proc/$CRASH_PROGRAM_ID/task/*; do + tid=$(basename $t) + cat /proc/$tid/stat | awk '{print $29}' >> $TMP +done + +mv $TMP $STACKDUMP_FILE diff --git a/tools/testing/selftests/coredump/stackdump_test.c b/tools/testing/selftests/coredump/stackdump_test.c new file mode 100644 index 000000000000..5a5a7a5f7e1d --- /dev/null +++ b/tools/testing/selftests/coredump/stackdump_test.c @@ -0,0 +1,1830 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <assert.h> +#include <fcntl.h> +#include <inttypes.h> +#include <libgen.h> +#include <limits.h> +#include <linux/coredump.h> +#include <linux/fs.h> +#include <linux/limits.h> +#include <pthread.h> +#include <string.h> +#include <sys/mount.h> +#include <poll.h> +#include <sys/epoll.h> +#include <sys/resource.h> +#include <sys/stat.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <unistd.h> + +#include "../kselftest_harness.h" +#include "../filesystems/wrappers.h" +#include "../pidfd/pidfd.h" + +#define STACKDUMP_FILE "stack_values" +#define STACKDUMP_SCRIPT "stackdump" +#define NUM_THREAD_SPAWN 128 + +#ifndef PAGE_SIZE +#define PAGE_SIZE 4096 +#endif + +static void *do_nothing(void *) +{ + while (1) + pause(); + + return NULL; +} + +static void crashing_child(void) +{ + pthread_t thread; + int i; + + for (i = 0; i < NUM_THREAD_SPAWN; ++i) + pthread_create(&thread, NULL, do_nothing, NULL); + + /* crash on purpose */ + i = *(int *)NULL; +} + +FIXTURE(coredump) +{ + char original_core_pattern[256]; + pid_t pid_coredump_server; + int fd_tmpfs_detached; +}; + +static int create_detached_tmpfs(void) +{ + int fd_context, fd_tmpfs; + + fd_context = sys_fsopen("tmpfs", 0); + if (fd_context < 0) + return -1; + + if (sys_fsconfig(fd_context, FSCONFIG_CMD_CREATE, NULL, NULL, 0) < 0) + return -1; + + fd_tmpfs = sys_fsmount(fd_context, 0, 0); + close(fd_context); + return fd_tmpfs; +} + +FIXTURE_SETUP(coredump) +{ + FILE *file; + int ret; + + self->pid_coredump_server = -ESRCH; + self->fd_tmpfs_detached = -1; + file = fopen("/proc/sys/kernel/core_pattern", "r"); + ASSERT_NE(NULL, file); + + ret = fread(self->original_core_pattern, 1, sizeof(self->original_core_pattern), file); + ASSERT_TRUE(ret || feof(file)); + ASSERT_LT(ret, sizeof(self->original_core_pattern)); + + self->original_core_pattern[ret] = '\0'; + self->fd_tmpfs_detached = create_detached_tmpfs(); + ASSERT_GE(self->fd_tmpfs_detached, 0); + + ret = fclose(file); + ASSERT_EQ(0, ret); +} + +FIXTURE_TEARDOWN(coredump) +{ + const char *reason; + FILE *file; + int ret, status; + + unlink(STACKDUMP_FILE); + + if (self->pid_coredump_server > 0) { + kill(self->pid_coredump_server, SIGTERM); + waitpid(self->pid_coredump_server, &status, 0); + } + unlink("/tmp/coredump.file"); + unlink("/tmp/coredump.socket"); + + file = fopen("/proc/sys/kernel/core_pattern", "w"); + if (!file) { + reason = "Unable to open core_pattern"; + goto fail; + } + + ret = fprintf(file, "%s", self->original_core_pattern); + if (ret < 0) { + reason = "Unable to write to core_pattern"; + goto fail; + } + + ret = fclose(file); + if (ret) { + reason = "Unable to close core_pattern"; + goto fail; + } + + if (self->fd_tmpfs_detached >= 0) { + ret = close(self->fd_tmpfs_detached); + if (ret < 0) { + reason = "Unable to close detached tmpfs"; + goto fail; + } + self->fd_tmpfs_detached = -1; + } + + return; +fail: + /* This should never happen */ + fprintf(stderr, "Failed to cleanup stackdump test: %s\n", reason); +} + +TEST_F_TIMEOUT(coredump, stackdump, 120) +{ + unsigned long long stack; + char *test_dir, *line; + size_t line_length; + char buf[PAGE_SIZE]; + int ret, i, status; + FILE *file; + pid_t pid; + + /* + * Step 1: Setup core_pattern so that the stackdump script is executed when the child + * process crashes + */ + ret = readlink("/proc/self/exe", buf, sizeof(buf)); + ASSERT_NE(-1, ret); + ASSERT_LT(ret, sizeof(buf)); + buf[ret] = '\0'; + + test_dir = dirname(buf); + + file = fopen("/proc/sys/kernel/core_pattern", "w"); + ASSERT_NE(NULL, file); + + ret = fprintf(file, "|%1$s/%2$s %%P %1$s/%3$s", test_dir, STACKDUMP_SCRIPT, STACKDUMP_FILE); + ASSERT_LT(0, ret); + + ret = fclose(file); + ASSERT_EQ(0, ret); + + /* Step 2: Create a process who spawns some threads then crashes */ + pid = fork(); + ASSERT_TRUE(pid >= 0); + if (pid == 0) + crashing_child(); + + /* + * Step 3: Wait for the stackdump script to write the stack pointers to the stackdump file + */ + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_TRUE(WCOREDUMP(status)); + + for (i = 0; i < 10; ++i) { + file = fopen(STACKDUMP_FILE, "r"); + if (file) + break; + sleep(1); + } + ASSERT_NE(file, NULL); + + /* Step 4: Make sure all stack pointer values are non-zero */ + line = NULL; + for (i = 0; -1 != getline(&line, &line_length, file); ++i) { + stack = strtoull(line, NULL, 10); + ASSERT_NE(stack, 0); + } + free(line); + + ASSERT_EQ(i, 1 + NUM_THREAD_SPAWN); + + 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, 128); + if (ret < 0) + goto out; + + return fd; + +out: + if (fd >= 0) + close(fd); + return -1; +} + +static bool set_core_pattern(const char *pattern) +{ + int fd; + ssize_t ret; + + fd = open("/proc/sys/kernel/core_pattern", O_WRONLY | O_CLOEXEC); + if (fd < 0) + return false; + + ret = write(fd, pattern, strlen(pattern)); + close(fd); + if (ret < 0) + return false; + + fprintf(stderr, "Set core_pattern to '%s' | %zu == %zu\n", pattern, ret, strlen(pattern)); + 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; + pid_t pid, pid_coredump_server; + struct stat st; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + 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 = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (!(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + + fd_core_file = creat("/tmp/coredump.file", 0644); + 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) + goto out; + + if (bytes_read == 0) + break; + + bytes_write = write(fd_core_file, buffer, bytes_read); + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_TRUE(WCOREDUMP(status)); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 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); + system("file /tmp/coredump.file"); +} + +TEST_F(coredump, socket_detect_userspace_client) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + struct stat st; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1; + int exit_code = EXIT_FAILURE; + + close(ipc_sockets[0]); + + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (info.coredump_mask & PIDFD_COREDUMPED) + goto out; + + if (read(fd_coredump, &c, 1) < 1) + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + 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); + + close(fd_socket); + _exit(EXIT_SUCCESS); + } + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFEXITED(status)); + ASSERT_EQ(WEXITSTATUS(status), 0); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_EQ((info.coredump_mask & PIDFD_COREDUMPED), 0); + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); + + ASSERT_NE(stat("/tmp/coredump.file", &st), 0); + ASSERT_EQ(errno, ENOENT); +} + +TEST_F(coredump, socket_enoent) +{ + int pidfd, status; + pid_t pid; + + ASSERT_TRUE(set_core_pattern("@/tmp/coredump.socket")); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_FALSE(WCOREDUMP(status)); +} + +TEST_F(coredump, socket_no_listener) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + 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); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + 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) + goto out; + + ret = bind(fd_server, (const struct sockaddr *)&coredump_sk, coredump_sk_len); + if (ret < 0) + goto out; + + 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_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_FALSE(WCOREDUMP(status)); + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +static ssize_t recv_marker(int fd) +{ + enum coredump_mark mark = COREDUMP_MARK_REQACK; + ssize_t ret; + + ret = recv(fd, &mark, sizeof(mark), MSG_WAITALL); + if (ret != sizeof(mark)) + return -1; + + switch (mark) { + case COREDUMP_MARK_REQACK: + fprintf(stderr, "Received marker: ReqAck\n"); + return COREDUMP_MARK_REQACK; + case COREDUMP_MARK_MINSIZE: + fprintf(stderr, "Received marker: MinSize\n"); + return COREDUMP_MARK_MINSIZE; + case COREDUMP_MARK_MAXSIZE: + fprintf(stderr, "Received marker: MaxSize\n"); + return COREDUMP_MARK_MAXSIZE; + case COREDUMP_MARK_UNSUPPORTED: + fprintf(stderr, "Received marker: Unsupported\n"); + return COREDUMP_MARK_UNSUPPORTED; + case COREDUMP_MARK_CONFLICTING: + fprintf(stderr, "Received marker: Conflicting\n"); + return COREDUMP_MARK_CONFLICTING; + default: + fprintf(stderr, "Received unknown marker: %u\n", mark); + break; + } + return -1; +} + +static bool read_marker(int fd, enum coredump_mark mark) +{ + ssize_t ret; + + ret = recv_marker(fd); + if (ret < 0) + return false; + return ret == mark; +} + +static bool read_coredump_req(int fd, struct coredump_req *req) +{ + ssize_t ret; + size_t field_size, user_size, ack_size, kernel_size, remaining_size; + + memset(req, 0, sizeof(*req)); + field_size = sizeof(req->size); + + /* Peek the size of the coredump request. */ + ret = recv(fd, req, field_size, MSG_PEEK | MSG_WAITALL); + if (ret != field_size) + return false; + kernel_size = req->size; + + if (kernel_size < COREDUMP_ACK_SIZE_VER0) + return false; + if (kernel_size >= PAGE_SIZE) + return false; + + /* Use the minimum of user and kernel size to read the full request. */ + user_size = sizeof(struct coredump_req); + ack_size = user_size < kernel_size ? user_size : kernel_size; + ret = recv(fd, req, ack_size, MSG_WAITALL); + if (ret != ack_size) + return false; + + fprintf(stderr, "Read coredump request with size %u and mask 0x%llx\n", + req->size, (unsigned long long)req->mask); + + if (user_size > kernel_size) + remaining_size = user_size - kernel_size; + else + remaining_size = kernel_size - user_size; + + if (PAGE_SIZE <= remaining_size) + return false; + + /* + * Discard any additional data if the kernel's request was larger than + * what we knew about or cared about. + */ + if (remaining_size) { + char buffer[PAGE_SIZE]; + + ret = recv(fd, buffer, sizeof(buffer), MSG_WAITALL); + if (ret != remaining_size) + return false; + fprintf(stderr, "Discarded %zu bytes of data after coredump request\n", remaining_size); + } + + return true; +} + +static bool send_coredump_ack(int fd, const struct coredump_req *req, + __u64 mask, size_t size_ack) +{ + ssize_t ret; + /* + * Wrap struct coredump_ack in a larger struct so we can + * simulate sending to much data to the kernel. + */ + struct large_ack_for_size_testing { + struct coredump_ack ack; + char buffer[PAGE_SIZE]; + } large_ack = {}; + + if (!size_ack) + size_ack = sizeof(struct coredump_ack) < req->size_ack ? + sizeof(struct coredump_ack) : + req->size_ack; + large_ack.ack.mask = mask; + large_ack.ack.size = size_ack; + ret = send(fd, &large_ack, size_ack, MSG_NOSIGNAL); + if (ret != size_ack) + return false; + + fprintf(stderr, "Sent coredump ack with size %zu and mask 0x%llx\n", + size_ack, (unsigned long long)mask); + return true; +} + +static bool check_coredump_req(const struct coredump_req *req, size_t min_size, + __u64 required_mask) +{ + if (req->size < min_size) + return false; + if ((req->mask & required_mask) != required_mask) + return false; + if (req->mask & ~required_mask) + return false; + return true; +} + +TEST_F(coredump, socket_request_kernel) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + struct stat st; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + struct coredump_req req = {}; + int fd_server = -1, fd_coredump = -1, fd_core_file = -1, fd_peer_pidfd = -1; + int exit_code = EXIT_FAILURE; + + close(ipc_sockets[0]); + + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (!(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + + fd_core_file = creat("/tmp/coredump.file", 0644); + if (fd_core_file < 0) + goto out; + + if (!read_coredump_req(fd_coredump, &req)) + goto out; + + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) + goto out; + + if (!send_coredump_ack(fd_coredump, &req, + COREDUMP_KERNEL | COREDUMP_WAIT, 0)) + goto out; + + if (!read_marker(fd_coredump, COREDUMP_MARK_REQACK)) + goto out; + + for (;;) { + char buffer[4096]; + ssize_t bytes_read, bytes_write; + + bytes_read = read(fd_coredump, buffer, sizeof(buffer)); + 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) + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_TRUE(WCOREDUMP(status)); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 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); + system("file /tmp/coredump.file"); +} + +TEST_F(coredump, socket_request_userspace) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + struct coredump_req req = {}; + int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1; + int exit_code = EXIT_FAILURE; + + close(ipc_sockets[0]); + + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (!(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + + if (!read_coredump_req(fd_coredump, &req)) + goto out; + + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) + goto out; + + if (!send_coredump_ack(fd_coredump, &req, + COREDUMP_USERSPACE | COREDUMP_WAIT, 0)) + goto out; + + if (!read_marker(fd_coredump, COREDUMP_MARK_REQACK)) + goto out; + + for (;;) { + char buffer[4096]; + ssize_t bytes_read; + + bytes_read = read(fd_coredump, buffer, sizeof(buffer)); + if (bytes_read > 0) + goto out; + + if (bytes_read < 0) + goto out; + + if (bytes_read == 0) + break; + } + + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_TRUE(WCOREDUMP(status)); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0); + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +TEST_F(coredump, socket_request_reject) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + struct coredump_req req = {}; + int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1; + int exit_code = EXIT_FAILURE; + + close(ipc_sockets[0]); + + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (!(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + + if (!read_coredump_req(fd_coredump, &req)) + goto out; + + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) + goto out; + + if (!send_coredump_ack(fd_coredump, &req, + COREDUMP_REJECT | COREDUMP_WAIT, 0)) + goto out; + + if (!read_marker(fd_coredump, COREDUMP_MARK_REQACK)) + goto out; + + for (;;) { + char buffer[4096]; + ssize_t bytes_read; + + bytes_read = read(fd_coredump, buffer, sizeof(buffer)); + if (bytes_read > 0) + goto out; + + if (bytes_read < 0) + goto out; + + if (bytes_read == 0) + break; + } + + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_FALSE(WCOREDUMP(status)); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0); + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +TEST_F(coredump, socket_request_invalid_flag_combination) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + struct coredump_req req = {}; + int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1; + int exit_code = EXIT_FAILURE; + + close(ipc_sockets[0]); + + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (!(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + + if (!read_coredump_req(fd_coredump, &req)) + goto out; + + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) + goto out; + + if (!send_coredump_ack(fd_coredump, &req, + COREDUMP_KERNEL | COREDUMP_REJECT | COREDUMP_WAIT, 0)) + goto out; + + if (!read_marker(fd_coredump, COREDUMP_MARK_CONFLICTING)) + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_FALSE(WCOREDUMP(status)); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0); + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +TEST_F(coredump, socket_request_unknown_flag) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + struct coredump_req req = {}; + int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1; + int exit_code = EXIT_FAILURE; + + close(ipc_sockets[0]); + + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (!(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + + if (!read_coredump_req(fd_coredump, &req)) + goto out; + + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) + goto out; + + if (!send_coredump_ack(fd_coredump, &req, (1ULL << 63), 0)) + goto out; + + if (!read_marker(fd_coredump, COREDUMP_MARK_UNSUPPORTED)) + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_FALSE(WCOREDUMP(status)); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0); + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +TEST_F(coredump, socket_request_invalid_size_small) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + struct coredump_req req = {}; + int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1; + int exit_code = EXIT_FAILURE; + + close(ipc_sockets[0]); + + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (!(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + + if (!read_coredump_req(fd_coredump, &req)) + goto out; + + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) + goto out; + + if (!send_coredump_ack(fd_coredump, &req, + COREDUMP_REJECT | COREDUMP_WAIT, + COREDUMP_ACK_SIZE_VER0 / 2)) + goto out; + + if (!read_marker(fd_coredump, COREDUMP_MARK_MINSIZE)) + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_FALSE(WCOREDUMP(status)); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0); + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +TEST_F(coredump, socket_request_invalid_size_large) +{ + int pidfd, ret, status; + pid_t pid, pid_coredump_server; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + + ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets); + ASSERT_EQ(ret, 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + struct coredump_req req = {}; + int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1; + int exit_code = EXIT_FAILURE; + + close(ipc_sockets[0]); + + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + 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) + goto out; + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + + if (!(info.mask & PIDFD_INFO_COREDUMP)) + goto out; + + if (!(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + + if (!read_coredump_req(fd_coredump, &req)) + goto out; + + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) + goto out; + + if (!send_coredump_ack(fd_coredump, &req, + COREDUMP_REJECT | COREDUMP_WAIT, + COREDUMP_ACK_SIZE_VER0 + PAGE_SIZE)) + goto out; + + if (!read_marker(fd_coredump, COREDUMP_MARK_MAXSIZE)) + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) + crashing_child(); + + pidfd = sys_pidfd_open(pid, 0); + ASSERT_GE(pidfd, 0); + + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFSIGNALED(status)); + ASSERT_FALSE(WCOREDUMP(status)); + + ASSERT_TRUE(get_pidfd_info(pidfd, &info)); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0); + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +static int open_coredump_tmpfile(int fd_tmpfs_detached) +{ + return openat(fd_tmpfs_detached, ".", O_TMPFILE | O_RDWR | O_EXCL, 0600); +} + +#define NUM_CRASHING_COREDUMPS 5 + +TEST_F_TIMEOUT(coredump, socket_multiple_crashing_coredumps, 500) +{ + int pidfd[NUM_CRASHING_COREDUMPS], status[NUM_CRASHING_COREDUMPS]; + pid_t pid[NUM_CRASHING_COREDUMPS], pid_coredump_server; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + + ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets), 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + int fd_server = -1, fd_coredump = -1, fd_peer_pidfd = -1, fd_core_file = -1; + int exit_code = EXIT_FAILURE; + struct coredump_req req = {}; + + close(ipc_sockets[0]); + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) { + fprintf(stderr, "Failed to create and listen on unix socket\n"); + goto out; + } + + if (write_nointr(ipc_sockets[1], "1", 1) < 0) { + fprintf(stderr, "Failed to notify parent via ipc socket\n"); + goto out; + } + close(ipc_sockets[1]); + + for (int i = 0; i < NUM_CRASHING_COREDUMPS; i++) { + fd_coredump = accept4(fd_server, NULL, NULL, SOCK_CLOEXEC); + if (fd_coredump < 0) { + fprintf(stderr, "accept4 failed: %m\n"); + goto out; + } + + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) { + fprintf(stderr, "get_peer_pidfd failed for fd %d: %m\n", fd_coredump); + goto out; + } + + if (!get_pidfd_info(fd_peer_pidfd, &info)) { + fprintf(stderr, "get_pidfd_info failed for fd %d\n", fd_peer_pidfd); + goto out; + } + + if (!(info.mask & PIDFD_INFO_COREDUMP)) { + fprintf(stderr, "pidfd info missing PIDFD_INFO_COREDUMP for fd %d\n", fd_peer_pidfd); + goto out; + } + if (!(info.coredump_mask & PIDFD_COREDUMPED)) { + fprintf(stderr, "pidfd info missing PIDFD_COREDUMPED for fd %d\n", fd_peer_pidfd); + goto out; + } + + if (!read_coredump_req(fd_coredump, &req)) { + fprintf(stderr, "read_coredump_req failed for fd %d\n", fd_coredump); + goto out; + } + + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) { + fprintf(stderr, "check_coredump_req failed for fd %d\n", fd_coredump); + goto out; + } + + if (!send_coredump_ack(fd_coredump, &req, + COREDUMP_KERNEL | COREDUMP_WAIT, 0)) { + fprintf(stderr, "send_coredump_ack failed for fd %d\n", fd_coredump); + goto out; + } + + if (!read_marker(fd_coredump, COREDUMP_MARK_REQACK)) { + fprintf(stderr, "read_marker failed for fd %d\n", fd_coredump); + goto out; + } + + fd_core_file = open_coredump_tmpfile(self->fd_tmpfs_detached); + if (fd_core_file < 0) { + fprintf(stderr, "%m - open_coredump_tmpfile failed for fd %d\n", fd_coredump); + goto out; + } + + for (;;) { + char buffer[4096]; + ssize_t bytes_read, bytes_write; + + bytes_read = read(fd_coredump, buffer, sizeof(buffer)); + if (bytes_read < 0) { + fprintf(stderr, "read failed for fd %d: %m\n", fd_coredump); + goto out; + } + + if (bytes_read == 0) + break; + + bytes_write = write(fd_core_file, buffer, bytes_read); + if (bytes_read != bytes_write) { + fprintf(stderr, "write failed for fd %d: %m\n", fd_core_file); + goto out; + } + } + + close(fd_core_file); + close(fd_peer_pidfd); + close(fd_coredump); + fd_peer_pidfd = -1; + fd_coredump = -1; + } + + 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); + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + for (int i = 0; i < NUM_CRASHING_COREDUMPS; i++) { + pid[i] = fork(); + ASSERT_GE(pid[i], 0); + if (pid[i] == 0) + crashing_child(); + pidfd[i] = sys_pidfd_open(pid[i], 0); + ASSERT_GE(pidfd[i], 0); + } + + for (int i = 0; i < NUM_CRASHING_COREDUMPS; i++) { + waitpid(pid[i], &status[i], 0); + ASSERT_TRUE(WIFSIGNALED(status[i])); + ASSERT_TRUE(WCOREDUMP(status[i])); + } + + for (int i = 0; i < NUM_CRASHING_COREDUMPS; i++) { + info.mask = PIDFD_INFO_EXIT | PIDFD_INFO_COREDUMP; + ASSERT_EQ(ioctl(pidfd[i], PIDFD_GET_INFO, &info), 0); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0); + } + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +#define MAX_EVENTS 128 + +static void process_coredump_worker(int fd_coredump, int fd_peer_pidfd, int fd_core_file) +{ + int epfd = -1; + int exit_code = EXIT_FAILURE; + + epfd = epoll_create1(0); + if (epfd < 0) + goto out; + + struct epoll_event ev; + ev.events = EPOLLIN | EPOLLRDHUP | EPOLLET; + ev.data.fd = fd_coredump; + if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd_coredump, &ev) < 0) + goto out; + + for (;;) { + struct epoll_event events[1]; + int n = epoll_wait(epfd, events, 1, -1); + if (n < 0) + break; + + if (events[0].events & (EPOLLIN | EPOLLRDHUP)) { + for (;;) { + char buffer[4096]; + ssize_t bytes_read = read(fd_coredump, buffer, sizeof(buffer)); + if (bytes_read < 0) { + if (errno == EAGAIN || errno == EWOULDBLOCK) + break; + goto out; + } + if (bytes_read == 0) + goto done; + ssize_t bytes_write = write(fd_core_file, buffer, bytes_read); + if (bytes_write != bytes_read) + goto out; + } + } + } + +done: + exit_code = EXIT_SUCCESS; +out: + if (epfd >= 0) + close(epfd); + 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); + _exit(exit_code); +} + +TEST_F_TIMEOUT(coredump, socket_multiple_crashing_coredumps_epoll_workers, 500) +{ + int pidfd[NUM_CRASHING_COREDUMPS], status[NUM_CRASHING_COREDUMPS]; + pid_t pid[NUM_CRASHING_COREDUMPS], pid_coredump_server, worker_pids[NUM_CRASHING_COREDUMPS]; + struct pidfd_info info = {}; + int ipc_sockets[2]; + char c; + + ASSERT_TRUE(set_core_pattern("@@/tmp/coredump.socket")); + ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, ipc_sockets), 0); + + pid_coredump_server = fork(); + ASSERT_GE(pid_coredump_server, 0); + if (pid_coredump_server == 0) { + int fd_server = -1, exit_code = EXIT_FAILURE, n_conns = 0; + fd_server = -1; + exit_code = EXIT_FAILURE; + n_conns = 0; + close(ipc_sockets[0]); + fd_server = create_and_listen_unix_socket("/tmp/coredump.socket"); + if (fd_server < 0) + goto out; + + if (write_nointr(ipc_sockets[1], "1", 1) < 0) + goto out; + close(ipc_sockets[1]); + + while (n_conns < NUM_CRASHING_COREDUMPS) { + int fd_coredump = -1, fd_peer_pidfd = -1, fd_core_file = -1; + struct coredump_req req = {}; + fd_coredump = accept4(fd_server, NULL, NULL, SOCK_CLOEXEC); + if (fd_coredump < 0) { + if (errno == EAGAIN || errno == EWOULDBLOCK) + continue; + goto out; + } + fd_peer_pidfd = get_peer_pidfd(fd_coredump); + if (fd_peer_pidfd < 0) + goto out; + if (!get_pidfd_info(fd_peer_pidfd, &info)) + goto out; + if (!(info.mask & PIDFD_INFO_COREDUMP) || !(info.coredump_mask & PIDFD_COREDUMPED)) + goto out; + if (!read_coredump_req(fd_coredump, &req)) + goto out; + if (!check_coredump_req(&req, COREDUMP_ACK_SIZE_VER0, + COREDUMP_KERNEL | COREDUMP_USERSPACE | + COREDUMP_REJECT | COREDUMP_WAIT)) + goto out; + if (!send_coredump_ack(fd_coredump, &req, COREDUMP_KERNEL | COREDUMP_WAIT, 0)) + goto out; + if (!read_marker(fd_coredump, COREDUMP_MARK_REQACK)) + goto out; + fd_core_file = open_coredump_tmpfile(self->fd_tmpfs_detached); + if (fd_core_file < 0) + goto out; + pid_t worker = fork(); + if (worker == 0) { + close(fd_server); + process_coredump_worker(fd_coredump, fd_peer_pidfd, fd_core_file); + } + worker_pids[n_conns] = worker; + if (fd_coredump >= 0) + close(fd_coredump); + if (fd_peer_pidfd >= 0) + close(fd_peer_pidfd); + if (fd_core_file >= 0) + close(fd_core_file); + n_conns++; + } + exit_code = EXIT_SUCCESS; +out: + if (fd_server >= 0) + close(fd_server); + + // Reap all worker processes + for (int i = 0; i < n_conns; i++) { + int wstatus; + if (waitpid(worker_pids[i], &wstatus, 0) < 0) { + fprintf(stderr, "Failed to wait for worker %d: %m\n", worker_pids[i]); + } else if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) != EXIT_SUCCESS) { + fprintf(stderr, "Worker %d exited with error code %d\n", worker_pids[i], WEXITSTATUS(wstatus)); + exit_code = EXIT_FAILURE; + } + } + + _exit(exit_code); + } + self->pid_coredump_server = pid_coredump_server; + + EXPECT_EQ(close(ipc_sockets[1]), 0); + ASSERT_EQ(read_nointr(ipc_sockets[0], &c, 1), 1); + EXPECT_EQ(close(ipc_sockets[0]), 0); + + for (int i = 0; i < NUM_CRASHING_COREDUMPS; i++) { + pid[i] = fork(); + ASSERT_GE(pid[i], 0); + if (pid[i] == 0) + crashing_child(); + pidfd[i] = sys_pidfd_open(pid[i], 0); + ASSERT_GE(pidfd[i], 0); + } + + for (int i = 0; i < NUM_CRASHING_COREDUMPS; i++) { + ASSERT_GE(waitpid(pid[i], &status[i], 0), 0); + ASSERT_TRUE(WIFSIGNALED(status[i])); + ASSERT_TRUE(WCOREDUMP(status[i])); + } + + for (int i = 0; i < NUM_CRASHING_COREDUMPS; i++) { + info.mask = PIDFD_INFO_EXIT | PIDFD_INFO_COREDUMP; + ASSERT_EQ(ioctl(pidfd[i], PIDFD_GET_INFO, &info), 0); + ASSERT_GT((info.mask & PIDFD_INFO_COREDUMP), 0); + ASSERT_GT((info.coredump_mask & PIDFD_COREDUMPED), 0); + } + + wait_and_check_coredump_server(pid_coredump_server, _metadata, self); +} + +TEST_F(coredump, socket_invalid_paths) +{ + ASSERT_FALSE(set_core_pattern("@ /tmp/coredump.socket")); + ASSERT_FALSE(set_core_pattern("@/tmp/../coredump.socket")); + ASSERT_FALSE(set_core_pattern("@../coredump.socket")); + ASSERT_FALSE(set_core_pattern("@/tmp/coredump.socket/..")); + ASSERT_FALSE(set_core_pattern("@..")); + + ASSERT_FALSE(set_core_pattern("@@ /tmp/coredump.socket")); + ASSERT_FALSE(set_core_pattern("@@/tmp/../coredump.socket")); + ASSERT_FALSE(set_core_pattern("@@../coredump.socket")); + ASSERT_FALSE(set_core_pattern("@@/tmp/coredump.socket/..")); + ASSERT_FALSE(set_core_pattern("@@..")); + + ASSERT_FALSE(set_core_pattern("@@@/tmp/coredump.socket")); +} + +TEST_HARNESS_MAIN |