From 0b76cc2fdf133927c307f851ba1bc9395ab09f5a Mon Sep 17 00:00:00 2001 From: Yu Watanabe Date: Tue, 18 Jul 2023 23:10:41 +0900 Subject: [PATCH] udev: split-out formatter and spawning commands from udev-event.c No functional changes, just refactoring. --- src/test/udev-rule-runner.c | 1 + src/udev/meson.build | 2 + src/udev/test-udev-event.c | 1 + src/udev/udev-event.c | 833 ------------------------------------ src/udev/udev-event.h | 32 +- src/udev/udev-format.c | 483 +++++++++++++++++++++ src/udev/udev-format.h | 18 + src/udev/udev-rules.c | 2 + src/udev/udev-spawn.c | 355 +++++++++++++++ src/udev/udev-spawn.h | 28 ++ src/udev/udevadm-test.c | 1 + src/udev/udevd.c | 3 +- 12 files changed, 898 insertions(+), 861 deletions(-) create mode 100644 src/udev/udev-format.c create mode 100644 src/udev/udev-format.h create mode 100644 src/udev/udev-spawn.c create mode 100644 src/udev/udev-spawn.h diff --git a/src/test/udev-rule-runner.c b/src/test/udev-rule-runner.c index fe854a3d2e..72296b3f0e 100644 --- a/src/test/udev-rule-runner.c +++ b/src/test/udev-rule-runner.c @@ -24,6 +24,7 @@ #include "string-util.h" #include "tests.h" #include "udev-event.h" +#include "udev-spawn.h" #include "version.h" static int device_new_from_synthetic_event(sd_device **ret, const char *syspath, const char *action) { diff --git a/src/udev/meson.build b/src/udev/meson.build index 2e14867ba7..3dbda3cc2f 100644 --- a/src/udev/meson.build +++ b/src/udev/meson.build @@ -21,8 +21,10 @@ libudevd_core_sources = files( 'net/link-config.c', 'udev-ctrl.c', 'udev-event.c', + 'udev-format.c', 'udev-node.c', 'udev-rules.c', + 'udev-spawn.c', 'udev-watch.c', 'udev-builtin-btrfs.c', 'udev-builtin-hwdb.c', diff --git a/src/udev/test-udev-event.c b/src/udev/test-udev-event.c index 42f435916b..4f43facd80 100644 --- a/src/udev/test-udev-event.c +++ b/src/udev/test-udev-event.c @@ -5,6 +5,7 @@ #include "strv.h" #include "tests.h" #include "udev-event.h" +#include "udev-spawn.h" #define BUF_SIZE 1024 diff --git a/src/udev/udev-event.c b/src/udev/udev-event.c index 745f29a88f..0876e478d8 100644 --- a/src/udev/udev-event.c +++ b/src/udev/udev-event.c @@ -1,58 +1,21 @@ /* SPDX-License-Identifier: GPL-2.0-or-later */ -#include -#include -#include -#include -#include -#include -#include -#include - -#include "sd-event.h" - #include "alloc-util.h" #include "device-internal.h" #include "device-private.h" #include "device-util.h" -#include "fd-util.h" #include "fs-util.h" -#include "format-util.h" #include "netif-naming-scheme.h" #include "netlink-util.h" -#include "parse-util.h" #include "path-util.h" -#include "process-util.h" -#include "signal-util.h" -#include "stdio-util.h" #include "string-util.h" #include "strv.h" -#include "strxcpyx.h" -#include "udev-builtin.h" #include "udev-event.h" #include "udev-node.h" #include "udev-trace.h" -#include "udev-util.h" #include "udev-watch.h" #include "user-util.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; - UdevEvent *udev_event_new(sd_device *dev, usec_t exec_delay_usec, sd_netlink *rtnl, int log_level) { UdevEvent *event; @@ -93,771 +56,6 @@ UdevEvent *udev_event_free(UdevEvent *event) { return mfree(event); } -typedef enum { - FORMAT_SUBST_DEVNODE, - FORMAT_SUBST_ATTR, - FORMAT_SUBST_ENV, - FORMAT_SUBST_KERNEL, - FORMAT_SUBST_KERNEL_NUMBER, - FORMAT_SUBST_DRIVER, - FORMAT_SUBST_DEVPATH, - FORMAT_SUBST_ID, - FORMAT_SUBST_MAJOR, - FORMAT_SUBST_MINOR, - FORMAT_SUBST_RESULT, - FORMAT_SUBST_PARENT, - FORMAT_SUBST_NAME, - FORMAT_SUBST_LINKS, - FORMAT_SUBST_ROOT, - FORMAT_SUBST_SYS, - _FORMAT_SUBST_TYPE_MAX, - _FORMAT_SUBST_TYPE_INVALID = -EINVAL, -} FormatSubstitutionType; - -struct subst_map_entry { - const char *name; - const char fmt; - FormatSubstitutionType type; -}; - -static const struct subst_map_entry map[] = { - { .name = "devnode", .fmt = 'N', .type = FORMAT_SUBST_DEVNODE }, - { .name = "tempnode", .fmt = 'N', .type = FORMAT_SUBST_DEVNODE }, /* deprecated */ - { .name = "attr", .fmt = 's', .type = FORMAT_SUBST_ATTR }, - { .name = "sysfs", .fmt = 's', .type = FORMAT_SUBST_ATTR }, /* deprecated */ - { .name = "env", .fmt = 'E', .type = FORMAT_SUBST_ENV }, - { .name = "kernel", .fmt = 'k', .type = FORMAT_SUBST_KERNEL }, - { .name = "number", .fmt = 'n', .type = FORMAT_SUBST_KERNEL_NUMBER }, - { .name = "driver", .fmt = 'd', .type = FORMAT_SUBST_DRIVER }, - { .name = "devpath", .fmt = 'p', .type = FORMAT_SUBST_DEVPATH }, - { .name = "id", .fmt = 'b', .type = FORMAT_SUBST_ID }, - { .name = "major", .fmt = 'M', .type = FORMAT_SUBST_MAJOR }, - { .name = "minor", .fmt = 'm', .type = FORMAT_SUBST_MINOR }, - { .name = "result", .fmt = 'c', .type = FORMAT_SUBST_RESULT }, - { .name = "parent", .fmt = 'P', .type = FORMAT_SUBST_PARENT }, - { .name = "name", .fmt = 'D', .type = FORMAT_SUBST_NAME }, - { .name = "links", .fmt = 'L', .type = FORMAT_SUBST_LINKS }, - { .name = "root", .fmt = 'r', .type = FORMAT_SUBST_ROOT }, - { .name = "sys", .fmt = 'S', .type = FORMAT_SUBST_SYS }, -}; - -static const char *format_type_to_string(FormatSubstitutionType t) { - for (size_t i = 0; i < ELEMENTSOF(map); i++) - if (map[i].type == t) - return map[i].name; - return NULL; -} - -static char format_type_to_char(FormatSubstitutionType t) { - for (size_t i = 0; i < ELEMENTSOF(map); i++) - if (map[i].type == t) - return map[i].fmt; - return '\0'; -} - -static int get_subst_type(const char **str, bool strict, FormatSubstitutionType *ret_type, char ret_attr[static UDEV_PATH_SIZE]) { - const char *p = *str, *q = NULL; - size_t i; - - assert(str); - assert(*str); - assert(ret_type); - assert(ret_attr); - - if (*p == '$') { - p++; - if (*p == '$') { - *str = p; - return 0; - } - for (i = 0; i < ELEMENTSOF(map); i++) - if ((q = startswith(p, map[i].name))) - break; - } else if (*p == '%') { - p++; - if (*p == '%') { - *str = p; - return 0; - } - - for (i = 0; i < ELEMENTSOF(map); i++) - if (*p == map[i].fmt) { - q = p + 1; - break; - } - } else - return 0; - if (!q) - /* When 'strict' flag is set, then '$' and '%' must be escaped. */ - return strict ? -EINVAL : 0; - - if (*q == '{') { - const char *start, *end; - size_t len; - - start = q + 1; - end = strchr(start, '}'); - if (!end) - return -EINVAL; - - len = end - start; - if (len == 0 || len >= UDEV_PATH_SIZE) - return -EINVAL; - - strnscpy(ret_attr, UDEV_PATH_SIZE, start, len); - q = end + 1; - } else - *ret_attr = '\0'; - - *str = q; - *ret_type = map[i].type; - return 1; -} - -static int safe_atou_optional_plus(const char *s, unsigned *ret) { - const char *p; - int r; - - assert(s); - assert(ret); - - /* Returns 1 if plus, 0 if no plus, negative on error */ - - p = endswith(s, "+"); - if (p) - s = strndupa_safe(s, p - s); - - r = safe_atou(s, ret); - if (r < 0) - return r; - - return !!p; -} - -static ssize_t udev_event_subst_format( - UdevEvent *event, - FormatSubstitutionType type, - const char *attr, - char *dest, - size_t l, - bool *ret_truncated) { - - sd_device *parent, *dev = ASSERT_PTR(ASSERT_PTR(event)->dev); - const char *val = NULL; - bool truncated = false; - char *s = dest; - int r; - - switch (type) { - case FORMAT_SUBST_DEVPATH: - r = sd_device_get_devpath(dev, &val); - if (r < 0) - return r; - strpcpy_full(&s, l, val, &truncated); - break; - case FORMAT_SUBST_KERNEL: - r = sd_device_get_sysname(dev, &val); - if (r < 0) - return r; - strpcpy_full(&s, l, val, &truncated); - break; - case FORMAT_SUBST_KERNEL_NUMBER: - r = sd_device_get_sysnum(dev, &val); - if (r == -ENOENT) - goto null_terminate; - if (r < 0) - return r; - strpcpy_full(&s, l, val, &truncated); - break; - case FORMAT_SUBST_ID: - if (!event->dev_parent) - goto null_terminate; - r = sd_device_get_sysname(event->dev_parent, &val); - if (r < 0) - return r; - strpcpy_full(&s, l, val, &truncated); - break; - case FORMAT_SUBST_DRIVER: - if (!event->dev_parent) - goto null_terminate; - r = sd_device_get_driver(event->dev_parent, &val); - if (r == -ENOENT) - goto null_terminate; - if (r < 0) - return r; - strpcpy_full(&s, l, val, &truncated); - break; - case FORMAT_SUBST_MAJOR: - case FORMAT_SUBST_MINOR: { - dev_t devnum; - - r = sd_device_get_devnum(dev, &devnum); - if (r < 0 && r != -ENOENT) - return r; - strpcpyf_full(&s, l, &truncated, "%u", r < 0 ? 0 : type == FORMAT_SUBST_MAJOR ? major(devnum) : minor(devnum)); - break; - } - case FORMAT_SUBST_RESULT: { - unsigned index = 0; /* 0 means whole string */ - bool has_plus; - - if (!event->program_result) - goto null_terminate; - - if (!isempty(attr)) { - r = safe_atou_optional_plus(attr, &index); - if (r < 0) - return r; - - has_plus = r; - } - - if (index == 0) - strpcpy_full(&s, l, event->program_result, &truncated); - else { - const char *start, *p; - unsigned i; - - p = skip_leading_chars(event->program_result, NULL); - - for (i = 1; i < index; i++) { - while (*p && !strchr(WHITESPACE, *p)) - p++; - p = skip_leading_chars(p, NULL); - if (*p == '\0') - break; - } - if (i != index) { - log_device_debug(dev, "requested part of result string not found"); - goto null_terminate; - } - - start = p; - /* %c{2+} copies the whole string from the second part on */ - if (has_plus) - strpcpy_full(&s, l, start, &truncated); - else { - while (*p && !strchr(WHITESPACE, *p)) - p++; - strnpcpy_full(&s, l, start, p - start, &truncated); - } - } - break; - } - case FORMAT_SUBST_ATTR: { - char vbuf[UDEV_NAME_SIZE]; - int count; - bool t; - - if (isempty(attr)) - return -EINVAL; - - /* try to read the value specified by "[dmi/id]product_name" */ - if (udev_resolve_subsys_kernel(attr, vbuf, sizeof(vbuf), true) == 0) - val = vbuf; - - /* try to read the attribute the device */ - if (!val) - (void) sd_device_get_sysattr_value(dev, attr, &val); - - /* try to read the attribute of the parent device, other matches have selected */ - if (!val && event->dev_parent && event->dev_parent != dev) - (void) sd_device_get_sysattr_value(event->dev_parent, attr, &val); - - if (!val) - goto null_terminate; - - /* strip trailing whitespace, and replace unwanted characters */ - if (val != vbuf) - strscpy_full(vbuf, sizeof(vbuf), val, &truncated); - delete_trailing_chars(vbuf, NULL); - count = udev_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT); - if (count > 0) - log_device_debug(dev, "%i character(s) replaced", count); - strpcpy_full(&s, l, vbuf, &t); - truncated = truncated || t; - break; - } - case FORMAT_SUBST_PARENT: - r = sd_device_get_parent(dev, &parent); - if (r == -ENOENT) - goto null_terminate; - if (r < 0) - return r; - r = sd_device_get_devname(parent, &val); - if (r == -ENOENT) - goto null_terminate; - if (r < 0) - return r; - strpcpy_full(&s, l, val + STRLEN("/dev/"), &truncated); - break; - case FORMAT_SUBST_DEVNODE: - r = sd_device_get_devname(dev, &val); - if (r == -ENOENT) - goto null_terminate; - if (r < 0) - return r; - strpcpy_full(&s, l, val, &truncated); - break; - case FORMAT_SUBST_NAME: - if (event->name) - strpcpy_full(&s, l, event->name, &truncated); - else if (sd_device_get_devname(dev, &val) >= 0) - strpcpy_full(&s, l, val + STRLEN("/dev/"), &truncated); - else { - r = sd_device_get_sysname(dev, &val); - if (r < 0) - return r; - strpcpy_full(&s, l, val, &truncated); - } - break; - case FORMAT_SUBST_LINKS: - FOREACH_DEVICE_DEVLINK(dev, link) { - if (s == dest) - strpcpy_full(&s, l, link + STRLEN("/dev/"), &truncated); - else - strpcpyl_full(&s, l, &truncated, " ", link + STRLEN("/dev/"), NULL); - if (truncated) - break; - } - if (s == dest) - goto null_terminate; - break; - case FORMAT_SUBST_ROOT: - strpcpy_full(&s, l, "/dev", &truncated); - break; - case FORMAT_SUBST_SYS: - strpcpy_full(&s, l, "/sys", &truncated); - break; - case FORMAT_SUBST_ENV: - if (isempty(attr)) - return -EINVAL; - r = sd_device_get_property_value(dev, attr, &val); - if (r == -ENOENT) - goto null_terminate; - if (r < 0) - return r; - strpcpy_full(&s, l, val, &truncated); - break; - default: - assert_not_reached(); - } - - if (ret_truncated) - *ret_truncated = truncated; - - return s - dest; - -null_terminate: - if (ret_truncated) - *ret_truncated = truncated; - - *s = '\0'; - return 0; -} - -size_t udev_event_apply_format( - UdevEvent *event, - const char *src, - char *dest, - size_t size, - bool replace_whitespace, - bool *ret_truncated) { - - bool truncated = false; - const char *s = ASSERT_PTR(src); - int r; - - assert(event); - assert(event->dev); - assert(dest); - assert(size > 0); - - while (*s) { - FormatSubstitutionType type; - char attr[UDEV_PATH_SIZE]; - ssize_t subst_len; - bool t; - - r = get_subst_type(&s, false, &type, attr); - if (r < 0) { - log_device_warning_errno(event->dev, r, "Invalid format string, ignoring: %s", src); - break; - } else if (r == 0) { - if (size < 2) { - /* need space for this char and the terminating NUL */ - truncated = true; - break; - } - *dest++ = *s++; - size--; - continue; - } - - subst_len = udev_event_subst_format(event, type, attr, dest, size, &t); - if (subst_len < 0) { - log_device_warning_errno(event->dev, subst_len, - "Failed to substitute variable '$%s' or apply format '%%%c', ignoring: %m", - format_type_to_string(type), format_type_to_char(type)); - break; - } - - truncated = truncated || t; - - /* FORMAT_SUBST_RESULT handles spaces itself */ - if (replace_whitespace && type != FORMAT_SUBST_RESULT) - /* udev_replace_whitespace can replace in-place, - * and does nothing if subst_len == 0 */ - subst_len = udev_replace_whitespace(dest, dest, subst_len); - - dest += subst_len; - size -= subst_len; - } - - assert(size >= 1); - - if (ret_truncated) - *ret_truncated = truncated; - - *dest = '\0'; - return size; -} - -int udev_check_format(const char *value, size_t *offset, const char **hint) { - FormatSubstitutionType type; - const char *s = value; - char attr[UDEV_PATH_SIZE]; - int r; - - while (*s) { - r = get_subst_type(&s, true, &type, attr); - if (r < 0) { - if (offset) - *offset = s - value; - if (hint) - *hint = "invalid substitution type"; - return r; - } else if (r == 0) { - s++; - continue; - } - - if (IN_SET(type, FORMAT_SUBST_ATTR, FORMAT_SUBST_ENV) && isempty(attr)) { - if (offset) - *offset = s - value; - if (hint) - *hint = "attribute value missing"; - return -EINVAL; - } - - if (type == FORMAT_SUBST_RESULT && !isempty(attr)) { - unsigned i; - - r = safe_atou_optional_plus(attr, &i); - if (r < 0) { - if (offset) - *offset = s - value; - if (hint) - *hint = "attribute value not a valid number"; - return r; - } - } - } - - return 0; -} - -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 ressize, - bool *ret_truncated) { - - _cleanup_close_pair_ int outpipe[2] = PIPE_EBADF, errpipe[2] = PIPE_EBADF; - _cleanup_strv_free_ char **argv = NULL; - char **envp = NULL; - Spawn spawn; - pid_t pid; - int r; - - assert(event); - assert(event->dev); - assert(result || ressize == 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|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 = ressize, - }; - 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 */ -} - static int device_rename(sd_device *device, const char *name) { _cleanup_free_ char *new_syspath = NULL; const char *s; @@ -1205,34 +403,3 @@ int udev_event_execute_rules( return 0; } - -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); - } - } -} diff --git a/src/udev/udev-event.h b/src/udev/udev-event.h index b99559ca2e..6b94fd08ab 100644 --- a/src/udev/udev-event.h +++ b/src/udev/udev-event.h @@ -5,17 +5,17 @@ * Copyright © 2003 Greg Kroah-Hartman */ +#include +#include + #include "sd-device.h" #include "sd-netlink.h" #include "hashmap.h" #include "macro.h" +#include "time-util.h" #include "udev-rules.h" -#include "udev-util.h" - -#define READ_END 0 -#define WRITE_END 1 -#define UDEV_ALLOWED_CHARS_INPUT "/ $%?," +#include "user-util.h" typedef struct UdevEvent { sd_device *dev; @@ -51,23 +51,6 @@ UdevEvent *udev_event_new(sd_device *dev, usec_t exec_delay_usec, sd_netlink *rt UdevEvent *udev_event_free(UdevEvent *event); DEFINE_TRIVIAL_CLEANUP_FUNC(UdevEvent*, udev_event_free); -size_t udev_event_apply_format( - UdevEvent *event, - const char *src, - char *dest, - size_t size, - bool replace_whitespace, - bool *ret_truncated); -int udev_check_format(const char *value, size_t *offset, const char **hint); -int udev_event_spawn( - UdevEvent *event, - usec_t timeout_usec, - int timeout_signal, - bool accept_failure, - const char *cmd, - char *result, - size_t ressize, - bool *ret_truncated); int udev_event_execute_rules( UdevEvent *event, int inotify_fd, @@ -75,8 +58,3 @@ int udev_event_execute_rules( int timeout_signal, Hashmap *properties_list, UdevRules *rules); -void udev_event_execute_run(UdevEvent *event, usec_t timeout_usec, int timeout_signal); - -static inline usec_t udev_warn_timeout(usec_t timeout_usec) { - return DIV_ROUND_UP(timeout_usec, 3); -} diff --git a/src/udev/udev-format.c b/src/udev/udev-format.c new file mode 100644 index 0000000000..b33d8646c6 --- /dev/null +++ b/src/udev/udev-format.c @@ -0,0 +1,483 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#include "device-util.h" +#include "parse-util.h" +#include "string-util.h" +#include "strxcpyx.h" +#include "udev-event.h" +#include "udev-format.h" +#include "udev-util.h" + +typedef enum { + FORMAT_SUBST_DEVNODE, + FORMAT_SUBST_ATTR, + FORMAT_SUBST_ENV, + FORMAT_SUBST_KERNEL, + FORMAT_SUBST_KERNEL_NUMBER, + FORMAT_SUBST_DRIVER, + FORMAT_SUBST_DEVPATH, + FORMAT_SUBST_ID, + FORMAT_SUBST_MAJOR, + FORMAT_SUBST_MINOR, + FORMAT_SUBST_RESULT, + FORMAT_SUBST_PARENT, + FORMAT_SUBST_NAME, + FORMAT_SUBST_LINKS, + FORMAT_SUBST_ROOT, + FORMAT_SUBST_SYS, + _FORMAT_SUBST_TYPE_MAX, + _FORMAT_SUBST_TYPE_INVALID = -EINVAL, +} FormatSubstitutionType; + +struct subst_map_entry { + const char *name; + const char fmt; + FormatSubstitutionType type; +}; + +static const struct subst_map_entry map[] = { + { .name = "devnode", .fmt = 'N', .type = FORMAT_SUBST_DEVNODE }, + { .name = "tempnode", .fmt = 'N', .type = FORMAT_SUBST_DEVNODE }, /* deprecated */ + { .name = "attr", .fmt = 's', .type = FORMAT_SUBST_ATTR }, + { .name = "sysfs", .fmt = 's', .type = FORMAT_SUBST_ATTR }, /* deprecated */ + { .name = "env", .fmt = 'E', .type = FORMAT_SUBST_ENV }, + { .name = "kernel", .fmt = 'k', .type = FORMAT_SUBST_KERNEL }, + { .name = "number", .fmt = 'n', .type = FORMAT_SUBST_KERNEL_NUMBER }, + { .name = "driver", .fmt = 'd', .type = FORMAT_SUBST_DRIVER }, + { .name = "devpath", .fmt = 'p', .type = FORMAT_SUBST_DEVPATH }, + { .name = "id", .fmt = 'b', .type = FORMAT_SUBST_ID }, + { .name = "major", .fmt = 'M', .type = FORMAT_SUBST_MAJOR }, + { .name = "minor", .fmt = 'm', .type = FORMAT_SUBST_MINOR }, + { .name = "result", .fmt = 'c', .type = FORMAT_SUBST_RESULT }, + { .name = "parent", .fmt = 'P', .type = FORMAT_SUBST_PARENT }, + { .name = "name", .fmt = 'D', .type = FORMAT_SUBST_NAME }, + { .name = "links", .fmt = 'L', .type = FORMAT_SUBST_LINKS }, + { .name = "root", .fmt = 'r', .type = FORMAT_SUBST_ROOT }, + { .name = "sys", .fmt = 'S', .type = FORMAT_SUBST_SYS }, +}; + +static const char *format_type_to_string(FormatSubstitutionType t) { + for (size_t i = 0; i < ELEMENTSOF(map); i++) + if (map[i].type == t) + return map[i].name; + return NULL; +} + +static char format_type_to_char(FormatSubstitutionType t) { + for (size_t i = 0; i < ELEMENTSOF(map); i++) + if (map[i].type == t) + return map[i].fmt; + return '\0'; +} + +static int get_subst_type(const char **str, bool strict, FormatSubstitutionType *ret_type, char ret_attr[static UDEV_PATH_SIZE]) { + const char *p = *str, *q = NULL; + size_t i; + + assert(str); + assert(*str); + assert(ret_type); + assert(ret_attr); + + if (*p == '$') { + p++; + if (*p == '$') { + *str = p; + return 0; + } + for (i = 0; i < ELEMENTSOF(map); i++) + if ((q = startswith(p, map[i].name))) + break; + } else if (*p == '%') { + p++; + if (*p == '%') { + *str = p; + return 0; + } + + for (i = 0; i < ELEMENTSOF(map); i++) + if (*p == map[i].fmt) { + q = p + 1; + break; + } + } else + return 0; + if (!q) + /* When 'strict' flag is set, then '$' and '%' must be escaped. */ + return strict ? -EINVAL : 0; + + if (*q == '{') { + const char *start, *end; + size_t len; + + start = q + 1; + end = strchr(start, '}'); + if (!end) + return -EINVAL; + + len = end - start; + if (len == 0 || len >= UDEV_PATH_SIZE) + return -EINVAL; + + strnscpy(ret_attr, UDEV_PATH_SIZE, start, len); + q = end + 1; + } else + *ret_attr = '\0'; + + *str = q; + *ret_type = map[i].type; + return 1; +} + +static int safe_atou_optional_plus(const char *s, unsigned *ret) { + const char *p; + int r; + + assert(s); + assert(ret); + + /* Returns 1 if plus, 0 if no plus, negative on error */ + + p = endswith(s, "+"); + if (p) + s = strndupa_safe(s, p - s); + + r = safe_atou(s, ret); + if (r < 0) + return r; + + return !!p; +} + +static ssize_t udev_event_subst_format( + UdevEvent *event, + FormatSubstitutionType type, + const char *attr, + char *dest, + size_t l, + bool *ret_truncated) { + + sd_device *parent, *dev = ASSERT_PTR(ASSERT_PTR(event)->dev); + const char *val = NULL; + bool truncated = false; + char *s = dest; + int r; + + switch (type) { + case FORMAT_SUBST_DEVPATH: + r = sd_device_get_devpath(dev, &val); + if (r < 0) + return r; + strpcpy_full(&s, l, val, &truncated); + break; + case FORMAT_SUBST_KERNEL: + r = sd_device_get_sysname(dev, &val); + if (r < 0) + return r; + strpcpy_full(&s, l, val, &truncated); + break; + case FORMAT_SUBST_KERNEL_NUMBER: + r = sd_device_get_sysnum(dev, &val); + if (r == -ENOENT) + goto null_terminate; + if (r < 0) + return r; + strpcpy_full(&s, l, val, &truncated); + break; + case FORMAT_SUBST_ID: + if (!event->dev_parent) + goto null_terminate; + r = sd_device_get_sysname(event->dev_parent, &val); + if (r < 0) + return r; + strpcpy_full(&s, l, val, &truncated); + break; + case FORMAT_SUBST_DRIVER: + if (!event->dev_parent) + goto null_terminate; + r = sd_device_get_driver(event->dev_parent, &val); + if (r == -ENOENT) + goto null_terminate; + if (r < 0) + return r; + strpcpy_full(&s, l, val, &truncated); + break; + case FORMAT_SUBST_MAJOR: + case FORMAT_SUBST_MINOR: { + dev_t devnum; + + r = sd_device_get_devnum(dev, &devnum); + if (r < 0 && r != -ENOENT) + return r; + strpcpyf_full(&s, l, &truncated, "%u", r < 0 ? 0 : type == FORMAT_SUBST_MAJOR ? major(devnum) : minor(devnum)); + break; + } + case FORMAT_SUBST_RESULT: { + unsigned index = 0; /* 0 means whole string */ + bool has_plus; + + if (!event->program_result) + goto null_terminate; + + if (!isempty(attr)) { + r = safe_atou_optional_plus(attr, &index); + if (r < 0) + return r; + + has_plus = r; + } + + if (index == 0) + strpcpy_full(&s, l, event->program_result, &truncated); + else { + const char *start, *p; + unsigned i; + + p = skip_leading_chars(event->program_result, NULL); + + for (i = 1; i < index; i++) { + while (*p && !strchr(WHITESPACE, *p)) + p++; + p = skip_leading_chars(p, NULL); + if (*p == '\0') + break; + } + if (i != index) { + log_device_debug(dev, "requested part of result string not found"); + goto null_terminate; + } + + start = p; + /* %c{2+} copies the whole string from the second part on */ + if (has_plus) + strpcpy_full(&s, l, start, &truncated); + else { + while (*p && !strchr(WHITESPACE, *p)) + p++; + strnpcpy_full(&s, l, start, p - start, &truncated); + } + } + break; + } + case FORMAT_SUBST_ATTR: { + char vbuf[UDEV_NAME_SIZE]; + int count; + bool t; + + if (isempty(attr)) + return -EINVAL; + + /* try to read the value specified by "[dmi/id]product_name" */ + if (udev_resolve_subsys_kernel(attr, vbuf, sizeof(vbuf), true) == 0) + val = vbuf; + + /* try to read the attribute the device */ + if (!val) + (void) sd_device_get_sysattr_value(dev, attr, &val); + + /* try to read the attribute of the parent device, other matches have selected */ + if (!val && event->dev_parent && event->dev_parent != dev) + (void) sd_device_get_sysattr_value(event->dev_parent, attr, &val); + + if (!val) + goto null_terminate; + + /* strip trailing whitespace, and replace unwanted characters */ + if (val != vbuf) + strscpy_full(vbuf, sizeof(vbuf), val, &truncated); + delete_trailing_chars(vbuf, NULL); + count = udev_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT); + if (count > 0) + log_device_debug(dev, "%i character(s) replaced", count); + strpcpy_full(&s, l, vbuf, &t); + truncated = truncated || t; + break; + } + case FORMAT_SUBST_PARENT: + r = sd_device_get_parent(dev, &parent); + if (r == -ENOENT) + goto null_terminate; + if (r < 0) + return r; + r = sd_device_get_devname(parent, &val); + if (r == -ENOENT) + goto null_terminate; + if (r < 0) + return r; + strpcpy_full(&s, l, val + STRLEN("/dev/"), &truncated); + break; + case FORMAT_SUBST_DEVNODE: + r = sd_device_get_devname(dev, &val); + if (r == -ENOENT) + goto null_terminate; + if (r < 0) + return r; + strpcpy_full(&s, l, val, &truncated); + break; + case FORMAT_SUBST_NAME: + if (event->name) + strpcpy_full(&s, l, event->name, &truncated); + else if (sd_device_get_devname(dev, &val) >= 0) + strpcpy_full(&s, l, val + STRLEN("/dev/"), &truncated); + else { + r = sd_device_get_sysname(dev, &val); + if (r < 0) + return r; + strpcpy_full(&s, l, val, &truncated); + } + break; + case FORMAT_SUBST_LINKS: + FOREACH_DEVICE_DEVLINK(dev, link) { + if (s == dest) + strpcpy_full(&s, l, link + STRLEN("/dev/"), &truncated); + else + strpcpyl_full(&s, l, &truncated, " ", link + STRLEN("/dev/"), NULL); + if (truncated) + break; + } + if (s == dest) + goto null_terminate; + break; + case FORMAT_SUBST_ROOT: + strpcpy_full(&s, l, "/dev", &truncated); + break; + case FORMAT_SUBST_SYS: + strpcpy_full(&s, l, "/sys", &truncated); + break; + case FORMAT_SUBST_ENV: + if (isempty(attr)) + return -EINVAL; + r = sd_device_get_property_value(dev, attr, &val); + if (r == -ENOENT) + goto null_terminate; + if (r < 0) + return r; + strpcpy_full(&s, l, val, &truncated); + break; + default: + assert_not_reached(); + } + + if (ret_truncated) + *ret_truncated = truncated; + + return s - dest; + +null_terminate: + if (ret_truncated) + *ret_truncated = truncated; + + *s = '\0'; + return 0; +} + +size_t udev_event_apply_format( + UdevEvent *event, + const char *src, + char *dest, + size_t size, + bool replace_whitespace, + bool *ret_truncated) { + + bool truncated = false; + const char *s = ASSERT_PTR(src); + int r; + + assert(event); + assert(event->dev); + assert(dest); + assert(size > 0); + + while (*s) { + FormatSubstitutionType type; + char attr[UDEV_PATH_SIZE]; + ssize_t subst_len; + bool t; + + r = get_subst_type(&s, false, &type, attr); + if (r < 0) { + log_device_warning_errno(event->dev, r, "Invalid format string, ignoring: %s", src); + break; + } else if (r == 0) { + if (size < 2) { + /* need space for this char and the terminating NUL */ + truncated = true; + break; + } + *dest++ = *s++; + size--; + continue; + } + + subst_len = udev_event_subst_format(event, type, attr, dest, size, &t); + if (subst_len < 0) { + log_device_warning_errno(event->dev, subst_len, + "Failed to substitute variable '$%s' or apply format '%%%c', ignoring: %m", + format_type_to_string(type), format_type_to_char(type)); + break; + } + + truncated = truncated || t; + + /* FORMAT_SUBST_RESULT handles spaces itself */ + if (replace_whitespace && type != FORMAT_SUBST_RESULT) + /* udev_replace_whitespace can replace in-place, + * and does nothing if subst_len == 0 */ + subst_len = udev_replace_whitespace(dest, dest, subst_len); + + dest += subst_len; + size -= subst_len; + } + + assert(size >= 1); + + if (ret_truncated) + *ret_truncated = truncated; + + *dest = '\0'; + return size; +} + +int udev_check_format(const char *value, size_t *offset, const char **hint) { + FormatSubstitutionType type; + const char *s = value; + char attr[UDEV_PATH_SIZE]; + int r; + + while (*s) { + r = get_subst_type(&s, true, &type, attr); + if (r < 0) { + if (offset) + *offset = s - value; + if (hint) + *hint = "invalid substitution type"; + return r; + } else if (r == 0) { + s++; + continue; + } + + if (IN_SET(type, FORMAT_SUBST_ATTR, FORMAT_SUBST_ENV) && isempty(attr)) { + if (offset) + *offset = s - value; + if (hint) + *hint = "attribute value missing"; + return -EINVAL; + } + + if (type == FORMAT_SUBST_RESULT && !isempty(attr)) { + unsigned i; + + r = safe_atou_optional_plus(attr, &i); + if (r < 0) { + if (offset) + *offset = s - value; + if (hint) + *hint = "attribute value not a valid number"; + return r; + } + } + } + + return 0; +} diff --git a/src/udev/udev-format.h b/src/udev/udev-format.h new file mode 100644 index 0000000000..0dbdd561b1 --- /dev/null +++ b/src/udev/udev-format.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#pragma once + +#include +#include + +typedef struct UdevEvent UdevEvent; + +#define UDEV_ALLOWED_CHARS_INPUT "/ $%?," + +size_t udev_event_apply_format( + UdevEvent *event, + const char *src, + char *dest, + size_t size, + bool replace_whitespace, + bool *ret_truncated); +int udev_check_format(const char *value, size_t *offset, const char **hint); diff --git a/src/udev/udev-rules.c b/src/udev/udev-rules.c index 2c9797f099..c4f2a7ffbb 100644 --- a/src/udev/udev-rules.c +++ b/src/udev/udev-rules.c @@ -30,8 +30,10 @@ #include "syslog-util.h" #include "udev-builtin.h" #include "udev-event.h" +#include "udev-format.h" #include "udev-node.h" #include "udev-rules.h" +#include "udev-spawn.h" #include "udev-trace.h" #include "udev-util.h" #include "user-util.h" diff --git a/src/udev/udev-spawn.c b/src/udev/udev-spawn.c new file mode 100644 index 0000000000..f90b9c62a1 --- /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 ressize, + bool *ret_truncated) { + + _cleanup_close_pair_ int outpipe[2] = PIPE_EBADF, errpipe[2] = PIPE_EBADF; + _cleanup_strv_free_ char **argv = NULL; + char **envp = NULL; + Spawn spawn; + pid_t pid; + int r; + + assert(event); + assert(event->dev); + assert(result || ressize == 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|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 = ressize, + }; + 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); + } + } +} diff --git a/src/udev/udev-spawn.h b/src/udev/udev-spawn.h new file mode 100644 index 0000000000..5efea2e886 --- /dev/null +++ b/src/udev/udev-spawn.h @@ -0,0 +1,28 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#pragma once + +#include +#include + +#include "macro.h" +#include "time-util.h" + +#define READ_END 0 +#define WRITE_END 1 + +typedef struct UdevEvent UdevEvent; + +int udev_event_spawn( + UdevEvent *event, + usec_t timeout_usec, + int timeout_signal, + bool accept_failure, + const char *cmd, + char *result, + size_t ressize, + bool *ret_truncated); +void udev_event_execute_run(UdevEvent *event, usec_t timeout_usec, int timeout_signal); + +static inline usec_t udev_warn_timeout(usec_t timeout_usec) { + return DIV_ROUND_UP(timeout_usec, 3); +} diff --git a/src/udev/udevadm-test.c b/src/udev/udevadm-test.c index 682ff56720..8590bf3bf5 100644 --- a/src/udev/udevadm-test.c +++ b/src/udev/udevadm-test.c @@ -21,6 +21,7 @@ #include "strxcpyx.h" #include "udev-builtin.h" #include "udev-event.h" +#include "udev-format.h" #include "udevadm-util.h" #include "udevadm.h" diff --git a/src/udev/udevd.c b/src/udev/udevd.c index b545abd3e4..a2b164e933 100644 --- a/src/udev/udevd.c +++ b/src/udev/udevd.c @@ -64,14 +64,15 @@ #include "strv.h" #include "strxcpyx.h" #include "syslog-util.h" -#include "udevd.h" #include "udev-builtin.h" #include "udev-ctrl.h" #include "udev-event.h" #include "udev-node.h" +#include "udev-spawn.h" #include "udev-trace.h" #include "udev-util.h" #include "udev-watch.h" +#include "udevd.h" #include "user-util.h" #include "version.h" -- 2.25.1