Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 355 insertions, 0 deletions

diff --git a/src/udev/udev-spawn.c b/src/udev/udev-spawn.c
new file mode 100644
index 0000000..67a3005
--- /dev/null
+++ b/src/udev/udev-spawn.c
@@ -0,0 +1,355 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "sd-event.h"
+
+#include "device-private.h"
+#include "device-util.h"
+#include "fd-util.h"
+#include "path-util.h"
+#include "process-util.h"
+#include "signal-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "udev-builtin.h"
+#include "udev-event.h"
+#include "udev-spawn.h"
+#include "udev-trace.h"
+
+typedef struct Spawn {
+        sd_device *device;
+        const char *cmd;
+        pid_t pid;
+        usec_t timeout_warn_usec;
+        usec_t timeout_usec;
+        int timeout_signal;
+        usec_t event_birth_usec;
+        bool accept_failure;
+        int fd_stdout;
+        int fd_stderr;
+        char *result;
+        size_t result_size;
+        size_t result_len;
+        bool truncated;
+} Spawn;
+
+static int on_spawn_io(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+        Spawn *spawn = ASSERT_PTR(userdata);
+        char buf[4096], *p;
+        size_t size;
+        ssize_t l;
+        int r;
+
+        assert(fd == spawn->fd_stdout || fd == spawn->fd_stderr);
+        assert(!spawn->result || spawn->result_len < spawn->result_size);
+
+        if (fd == spawn->fd_stdout && spawn->result) {
+                p = spawn->result + spawn->result_len;
+                size = spawn->result_size - spawn->result_len;
+        } else {
+                p = buf;
+                size = sizeof(buf);
+        }
+
+        l = read(fd, p, size - (p == buf));
+        if (l < 0) {
+                if (errno == EAGAIN)
+                        goto reenable;
+
+                log_device_error_errno(spawn->device, errno,
+                                       "Failed to read stdout of '%s': %m", spawn->cmd);
+
+                return 0;
+        }
+
+        if ((size_t) l == size) {
+                log_device_warning(spawn->device, "Truncating stdout of '%s' up to %zu byte.",
+                                   spawn->cmd, spawn->result_size);
+                l--;
+                spawn->truncated = true;
+        }
+
+        p[l] = '\0';
+        if (fd == spawn->fd_stdout && spawn->result)
+                spawn->result_len += l;
+
+        /* Log output only if we watch stderr. */
+        if (l > 0 && spawn->fd_stderr >= 0) {
+                _cleanup_strv_free_ char **v = NULL;
+
+                r = strv_split_newlines_full(&v, p, EXTRACT_RETAIN_ESCAPE);
+                if (r < 0)
+                        log_device_debug(spawn->device,
+                                         "Failed to split output from '%s'(%s), ignoring: %m",
+                                         spawn->cmd, fd == spawn->fd_stdout ? "out" : "err");
+
+                STRV_FOREACH(q, v)
+                        log_device_debug(spawn->device, "'%s'(%s) '%s'", spawn->cmd,
+                                         fd == spawn->fd_stdout ? "out" : "err", *q);
+        }
+
+        if (l == 0 || spawn->truncated)
+                return 0;
+
+reenable:
+        /* Re-enable the event source if we did not encounter EOF */
+
+        r = sd_event_source_set_enabled(s, SD_EVENT_ONESHOT);
+        if (r < 0)
+                log_device_error_errno(spawn->device, r,
+                                       "Failed to reactivate IO source of '%s'", spawn->cmd);
+        return 0;
+}
+
+static int on_spawn_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
+        Spawn *spawn = ASSERT_PTR(userdata);
+
+        DEVICE_TRACE_POINT(spawn_timeout, spawn->device, spawn->cmd);
+
+        kill_and_sigcont(spawn->pid, spawn->timeout_signal);
+
+        log_device_error(spawn->device, "Spawned process '%s' ["PID_FMT"] timed out after %s, killing",
+                         spawn->cmd, spawn->pid,
+                         FORMAT_TIMESPAN(spawn->timeout_usec, USEC_PER_SEC));
+
+        return 1;
+}
+
+static int on_spawn_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) {
+        Spawn *spawn = ASSERT_PTR(userdata);
+
+        log_device_warning(spawn->device, "Spawned process '%s' ["PID_FMT"] is taking longer than %s to complete",
+                           spawn->cmd, spawn->pid,
+                           FORMAT_TIMESPAN(spawn->timeout_warn_usec, USEC_PER_SEC));
+
+        return 1;
+}
+
+static int on_spawn_sigchld(sd_event_source *s, const siginfo_t *si, void *userdata) {
+        Spawn *spawn = ASSERT_PTR(userdata);
+        int ret = -EIO;
+
+        switch (si->si_code) {
+        case CLD_EXITED:
+                if (si->si_status == 0)
+                        log_device_debug(spawn->device, "Process '%s' succeeded.", spawn->cmd);
+                else
+                        log_device_full(spawn->device, spawn->accept_failure ? LOG_DEBUG : LOG_WARNING,
+                                        "Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
+                ret = si->si_status;
+                break;
+        case CLD_KILLED:
+        case CLD_DUMPED:
+                log_device_error(spawn->device, "Process '%s' terminated by signal %s.", spawn->cmd, signal_to_string(si->si_status));
+                break;
+        default:
+                log_device_error(spawn->device, "Process '%s' failed due to unknown reason.", spawn->cmd);
+        }
+
+        DEVICE_TRACE_POINT(spawn_exit, spawn->device, spawn->cmd);
+
+        sd_event_exit(sd_event_source_get_event(s), ret);
+        return 1;
+}
+
+static int spawn_wait(Spawn *spawn) {
+        _cleanup_(sd_event_unrefp) sd_event *e = NULL;
+        _cleanup_(sd_event_source_disable_unrefp) sd_event_source *sigchld_source = NULL;
+        _cleanup_(sd_event_source_disable_unrefp) sd_event_source *stdout_source = NULL;
+        _cleanup_(sd_event_source_disable_unrefp) sd_event_source *stderr_source = NULL;
+        int r;
+
+        assert(spawn);
+
+        r = sd_event_new(&e);
+        if (r < 0)
+                return log_device_debug_errno(spawn->device, r, "Failed to allocate sd-event object: %m");
+
+        if (spawn->timeout_usec > 0) {
+                usec_t usec, age_usec;
+
+                usec = now(CLOCK_MONOTONIC);
+                age_usec = usec - spawn->event_birth_usec;
+                if (age_usec < spawn->timeout_usec) {
+                        if (spawn->timeout_warn_usec > 0 &&
+                            spawn->timeout_warn_usec < spawn->timeout_usec &&
+                            spawn->timeout_warn_usec > age_usec) {
+                                spawn->timeout_warn_usec -= age_usec;
+
+                                r = sd_event_add_time(e, NULL, CLOCK_MONOTONIC,
+                                                      usec + spawn->timeout_warn_usec, USEC_PER_SEC,
+                                                      on_spawn_timeout_warning, spawn);
+                                if (r < 0)
+                                        return log_device_debug_errno(spawn->device, r, "Failed to create timeout warning event source: %m");
+                        }
+
+                        spawn->timeout_usec -= age_usec;
+
+                        r = sd_event_add_time(e, NULL, CLOCK_MONOTONIC,
+                                              usec + spawn->timeout_usec, USEC_PER_SEC, on_spawn_timeout, spawn);
+                        if (r < 0)
+                                return log_device_debug_errno(spawn->device, r, "Failed to create timeout event source: %m");
+                }
+        }
+
+        if (spawn->fd_stdout >= 0) {
+                r = sd_event_add_io(e, &stdout_source, spawn->fd_stdout, EPOLLIN, on_spawn_io, spawn);
+                if (r < 0)
+                        return log_device_debug_errno(spawn->device, r, "Failed to create stdio event source: %m");
+                r = sd_event_source_set_enabled(stdout_source, SD_EVENT_ONESHOT);
+                if (r < 0)
+                        return log_device_debug_errno(spawn->device, r, "Failed to enable stdio event source: %m");
+        }
+
+        if (spawn->fd_stderr >= 0) {
+                r = sd_event_add_io(e, &stderr_source, spawn->fd_stderr, EPOLLIN, on_spawn_io, spawn);
+                if (r < 0)
+                        return log_device_debug_errno(spawn->device, r, "Failed to create stderr event source: %m");
+                r = sd_event_source_set_enabled(stderr_source, SD_EVENT_ONESHOT);
+                if (r < 0)
+                        return log_device_debug_errno(spawn->device, r, "Failed to enable stderr event source: %m");
+        }
+
+        r = sd_event_add_child(e, &sigchld_source, spawn->pid, WEXITED, on_spawn_sigchld, spawn);
+        if (r < 0)
+                return log_device_debug_errno(spawn->device, r, "Failed to create sigchild event source: %m");
+        /* SIGCHLD should be processed after IO is complete */
+        r = sd_event_source_set_priority(sigchld_source, SD_EVENT_PRIORITY_NORMAL + 1);
+        if (r < 0)
+                return log_device_debug_errno(spawn->device, r, "Failed to set priority to sigchild event source: %m");
+
+        return sd_event_loop(e);
+}
+
+int udev_event_spawn(
+                UdevEvent *event,
+                usec_t timeout_usec,
+                int timeout_signal,
+                bool accept_failure,
+                const char *cmd,
+                char *result,
+                size_t result_size,
+                bool *ret_truncated) {
+
+        _cleanup_close_pair_ int outpipe[2] = EBADF_PAIR, errpipe[2] = EBADF_PAIR;
+        _cleanup_strv_free_ char **argv = NULL;
+        char **envp = NULL;
+        Spawn spawn;
+        pid_t pid;
+        int r;
+
+        assert(event);
+        assert(event->dev);
+        assert(result || result_size == 0);
+
+        /* pipes from child to parent */
+        if (result || log_get_max_level() >= LOG_INFO)
+                if (pipe2(outpipe, O_NONBLOCK|O_CLOEXEC) != 0)
+                        return log_device_error_errno(event->dev, errno,
+                                                      "Failed to create pipe for command '%s': %m", cmd);
+
+        if (log_get_max_level() >= LOG_INFO)
+                if (pipe2(errpipe, O_NONBLOCK|O_CLOEXEC) != 0)
+                        return log_device_error_errno(event->dev, errno,
+                                                      "Failed to create pipe for command '%s': %m", cmd);
+
+        r = strv_split_full(&argv, cmd, NULL, EXTRACT_UNQUOTE | EXTRACT_RELAX | EXTRACT_RETAIN_ESCAPE);
+        if (r < 0)
+                return log_device_error_errno(event->dev, r, "Failed to split command: %m");
+
+        if (isempty(argv[0]))
+                return log_device_error_errno(event->dev, SYNTHETIC_ERRNO(EINVAL),
+                                              "Invalid command '%s'", cmd);
+
+        /* allow programs in /usr/lib/udev/ to be called without the path */
+        if (!path_is_absolute(argv[0])) {
+                char *program;
+
+                program = path_join(UDEVLIBEXECDIR, argv[0]);
+                if (!program)
+                        return log_oom();
+
+                free_and_replace(argv[0], program);
+        }
+
+        r = device_get_properties_strv(event->dev, &envp);
+        if (r < 0)
+                return log_device_error_errno(event->dev, r, "Failed to get device properties");
+
+        log_device_debug(event->dev, "Starting '%s'", cmd);
+
+        r = safe_fork_full("(spawn)",
+                           (int[]) { -EBADF, outpipe[WRITE_END], errpipe[WRITE_END] },
+                           NULL, 0,
+                           FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_DEATHSIG_SIGTERM|FORK_REARRANGE_STDIO|FORK_LOG|FORK_RLIMIT_NOFILE_SAFE,
+                           &pid);
+        if (r < 0)
+                return log_device_error_errno(event->dev, r,
+                                              "Failed to fork() to execute command '%s': %m", cmd);
+        if (r == 0) {
+                DEVICE_TRACE_POINT(spawn_exec, event->dev, cmd);
+                execve(argv[0], argv, envp);
+                _exit(EXIT_FAILURE);
+        }
+
+        /* parent closed child's ends of pipes */
+        outpipe[WRITE_END] = safe_close(outpipe[WRITE_END]);
+        errpipe[WRITE_END] = safe_close(errpipe[WRITE_END]);
+
+        spawn = (Spawn) {
+                .device = event->dev,
+                .cmd = cmd,
+                .pid = pid,
+                .accept_failure = accept_failure,
+                .timeout_warn_usec = udev_warn_timeout(timeout_usec),
+                .timeout_usec = timeout_usec,
+                .timeout_signal = timeout_signal,
+                .event_birth_usec = event->birth_usec,
+                .fd_stdout = outpipe[READ_END],
+                .fd_stderr = errpipe[READ_END],
+                .result = result,
+                .result_size = result_size,
+        };
+        r = spawn_wait(&spawn);
+        if (r < 0)
+                return log_device_error_errno(event->dev, r,
+                                              "Failed to wait for spawned command '%s': %m", cmd);
+
+        if (result)
+                result[spawn.result_len] = '\0';
+
+        if (ret_truncated)
+                *ret_truncated = spawn.truncated;
+
+        return r; /* 0 for success, and positive if the program failed */
+}
+
+void udev_event_execute_run(UdevEvent *event, usec_t timeout_usec, int timeout_signal) {
+        const char *command;
+        void *val;
+        int r;
+
+        ORDERED_HASHMAP_FOREACH_KEY(val, command, event->run_list) {
+                UdevBuiltinCommand builtin_cmd = PTR_TO_UDEV_BUILTIN_CMD(val);
+
+                if (builtin_cmd != _UDEV_BUILTIN_INVALID) {
+                        log_device_debug(event->dev, "Running built-in command \"%s\"", command);
+                        r = udev_builtin_run(event, builtin_cmd, command, false);
+                        if (r < 0)
+                                log_device_debug_errno(event->dev, r, "Failed to run built-in command \"%s\", ignoring: %m", command);
+                } else {
+                        if (event->exec_delay_usec > 0) {
+                                log_device_debug(event->dev, "Delaying execution of \"%s\" for %s.",
+                                                 command, FORMAT_TIMESPAN(event->exec_delay_usec, USEC_PER_SEC));
+                                (void) usleep_safe(event->exec_delay_usec);
+                        }
+
+                        log_device_debug(event->dev, "Running command \"%s\"", command);
+
+                        r = udev_event_spawn(event, timeout_usec, timeout_signal, false, command, NULL, 0, NULL);
+                        if (r < 0)
+                                log_device_warning_errno(event->dev, r, "Failed to execute '%s', ignoring: %m", command);
+                        else if (r > 0) /* returned value is positive when program fails */
+                                log_device_debug(event->dev, "Command \"%s\" returned %d (error), ignoring.", command, r);
+                }
+        }
+}