--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __COREDUMP_TEST_H
+#define __COREDUMP_TEST_H
+
+#include <stdbool.h>
+#include <sys/types.h>
+#include <linux/coredump.h>
+
+#include "../kselftest_harness.h"
+#include "../pidfd/pidfd.h"
+
+#ifndef PAGE_SIZE
+#define PAGE_SIZE 4096
+#endif
+
+#define NUM_THREAD_SPAWN 128
+
+/* Coredump fixture */
+FIXTURE(coredump)
+{
+ char original_core_pattern[256];
+ pid_t pid_coredump_server;
+ int fd_tmpfs_detached;
+};
+
+/* Shared helper function declarations */
+void *do_nothing(void *arg);
+void crashing_child(void);
+int create_detached_tmpfs(void);
+int create_and_listen_unix_socket(const char *path);
+bool set_core_pattern(const char *pattern);
+int get_peer_pidfd(int fd);
+bool get_pidfd_info(int fd_peer_pidfd, struct pidfd_info *info);
+
+/* Inline helper that uses harness types */
+static inline 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);
+}
+
+/* Protocol helper function declarations */
+ssize_t recv_marker(int fd);
+bool read_marker(int fd, enum coredump_mark mark);
+bool read_coredump_req(int fd, struct coredump_req *req);
+bool send_coredump_ack(int fd, const struct coredump_req *req,
+ __u64 mask, size_t size_ack);
+bool check_coredump_req(const struct coredump_req *req, size_t min_size,
+ __u64 required_mask);
+int open_coredump_tmpfile(int fd_tmpfs_detached);
+void process_coredump_worker(int fd_coredump, int fd_peer_pidfd, int fd_core_file);
+
+#endif /* __COREDUMP_TEST_H */
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <linux/coredump.h>
+#include <linux/fs.h>
+#include <pthread.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/epoll.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "../filesystems/wrappers.h"
+#include "../pidfd/pidfd.h"
+
+/* Forward declarations to avoid including harness header */
+struct __test_metadata;
+
+/* Match the fixture definition from coredump_test.h */
+struct _fixture_coredump_data {
+ char original_core_pattern[256];
+ pid_t pid_coredump_server;
+ int fd_tmpfs_detached;
+};
+
+#ifndef PAGE_SIZE
+#define PAGE_SIZE 4096
+#endif
+
+#define NUM_THREAD_SPAWN 128
+
+void *do_nothing(void *arg)
+{
+ (void)arg;
+ while (1)
+ pause();
+
+ return NULL;
+}
+
+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;
+}
+
+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;
+}
+
+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;
+}
+
+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);
+}
+
+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;
+}
+
+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 | PIDFD_INFO_COREDUMP_SIGNAL;
+ return ioctl(fd_peer_pidfd, PIDFD_GET_INFO, info) == 0;
+}
+
+/* Protocol helper functions */
+
+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;
+}
+
+bool read_marker(int fd, enum coredump_mark mark)
+{
+ ssize_t ret;
+
+ ret = recv_marker(fd);
+ if (ret < 0)
+ return false;
+ return ret == mark;
+}
+
+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;
+}
+
+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;
+}
+
+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;
+}
+
+int open_coredump_tmpfile(int fd_tmpfs_detached)
+{
+ return openat(fd_tmpfs_detached, ".", O_TMPFILE | O_RDWR | O_EXCL, 0600);
+}
+
+void process_coredump_worker(int fd_coredump, int fd_peer_pidfd, int fd_core_file)
+{
+ int epfd = -1;
+ int exit_code = EXIT_FAILURE;
+ struct epoll_event ev;
+
+ epfd = epoll_create1(0);
+ if (epfd < 0)
+ goto out;
+
+ 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);
+}
projects / thirdparty / linux.git / commitdiff
