From 14cc73f9bc65b38988f4051625cf5582be4150ef Mon Sep 17 00:00:00 2001 From: Tom Gundersen Date: Sun, 7 Jul 2013 18:32:34 +0200 Subject: [PATCH 1/2] udev: export tags of "dead" device nodes to /run/udev/static_node-tags Based on a patch by Kay Sievers. The difference being that the name of a specific tag ("uaccess") is not hardcoded. --- man/udev.xml | 8 ++++--- src/login/70-uaccess.rules | 3 ++- src/udev/udev-rules.c | 58 ++++++++++++++++++++++++++++++++++++++++++---- src/udev/udev.h | 2 +- src/udev/udevd.c | 3 ++- 5 files changed, 63 insertions(+), 11 deletions(-) diff --git a/man/udev.xml b/man/udev.xml index 553bbfd..5519990 100644 --- a/man/udev.xml +++ b/man/udev.xml @@ -521,9 +521,11 @@ Apply the permissions specified in this rule to the static device node with - the specified name. Static device node creation can be requested by kernel modules. - These nodes might not have a corresponding kernel device at the time systemd-udevd is - started; they can trigger automatic kernel module loading. + the specified name. Also write the tags specified in this rule to + /run/udev/static_node-tags. Static device node creation is + performed by systemd-tmpfiles before systemd-udevd is started. The static nodes + might not have a corresponding kernel device; they are used to trigger automatic + kernel module loading when they are accessed. diff --git a/src/login/70-uaccess.rules b/src/login/70-uaccess.rules index a118f8e..01484c9 100644 --- a/src/login/70-uaccess.rules +++ b/src/login/70-uaccess.rules @@ -25,7 +25,8 @@ SUBSYSTEM=="block", ENV{ID_CDROM}=="1", TAG+="uaccess" SUBSYSTEM=="scsi_generic", SUBSYSTEMS=="scsi", ATTRS{type}=="4|5", TAG+="uaccess" # Sound devices -SUBSYSTEM=="sound", TAG+="uaccess" +SUBSYSTEM=="sound", TAG+="uaccess" \ + OPTIONS+="static_node=snd/timer", OPTIONS+="static_node=snd/seq" # ffado is an userspace driver for firewire sound cards SUBSYSTEM=="firewire", ENV{ID_FFADO}=="1", TAG+="uaccess" diff --git a/src/udev/udev-rules.c b/src/udev/udev-rules.c index fe65e2d..5075cb2 100644 --- a/src/udev/udev-rules.c +++ b/src/udev/udev-rules.c @@ -33,6 +33,7 @@ #include "path-util.h" #include "conf-files.h" #include "strbuf.h" +#include "strv.h" #define PREALLOC_TOKEN 2048 @@ -152,9 +153,9 @@ enum token_type { TK_A_OWNER_ID, /* uid_t */ TK_A_GROUP_ID, /* gid_t */ TK_A_MODE_ID, /* mode_t */ + TK_A_TAG, /* val */ TK_A_STATIC_NODE, /* val */ TK_A_ENV, /* val, attr */ - TK_A_TAG, /* val */ TK_A_NAME, /* val */ TK_A_DEVLINK, /* val */ TK_A_ATTR, /* val, attr */ @@ -2496,16 +2497,21 @@ int udev_rules_apply_to_event(struct udev_rules *rules, struct udev_event *event } } -void udev_rules_apply_static_dev_perms(struct udev_rules *rules) +int udev_rules_apply_static_dev_perms(struct udev_rules *rules) { struct token *cur; struct token *rule; uid_t uid = 0; gid_t gid = 0; mode_t mode = 0; + _cleanup_strv_free_ char **tags = NULL; + char **t; + FILE *f = NULL; + _cleanup_free_ char *path = NULL; + int r = 0; if (rules->tokens == NULL) - return; + return 0; cur = &rules->tokens[0]; rule = cur; @@ -2522,6 +2528,8 @@ void udev_rules_apply_static_dev_perms(struct udev_rules *rules) uid = 0; gid = 0; mode = 0; + strv_free(tags); + tags = NULL; break; case TK_A_OWNER_ID: uid = cur->key.uid; @@ -2532,18 +2540,44 @@ void udev_rules_apply_static_dev_perms(struct udev_rules *rules) case TK_A_MODE_ID: mode = cur->key.mode; break; + case TK_A_TAG: + t = strv_append(tags, rules_str(rules, cur->key.value_off)); + if (!t) { + r = -ENOMEM; + goto finish; + } + + strv_free(tags); + tags = t; + break; case TK_A_STATIC_NODE: { char filename[UTIL_PATH_SIZE]; struct stat stats; /* we assure, that the permissions tokens are sorted before the static token */ - if (mode == 0 && uid == 0 && gid == 0) + if (mode == 0 && uid == 0 && gid == 0 && tags == NULL) goto next; strscpyl(filename, sizeof(filename), "/dev/", rules_str(rules, cur->key.value_off), NULL); if (stat(filename, &stats) != 0) goto next; if (!S_ISBLK(stats.st_mode) && !S_ISCHR(stats.st_mode)) goto next; + + if (tags) { + if (!f) { + /* Export the tags to a file, allowing otherwise dead nodes to be tagged */ + r = fopen_temporary("/run/udev/static_node-tags", &f, &path); + if (r < 0) { + log_error("failed to create /run/udev/static_node-tags: %s\n", strerror(-r)); + return r; + } + } + + STRV_FOREACH(t, tags) { + fprintf(f, "%s %s\n", filename, *t); + } + } + if (mode == 0) { if (gid > 0) mode = 0660; @@ -2564,7 +2598,7 @@ void udev_rules_apply_static_dev_perms(struct udev_rules *rules) break; } case TK_END: - return; + goto finish; } cur++; @@ -2574,4 +2608,18 @@ next: cur = rule + rule->rule.token_count; continue; } + +finish: + if (f) { + fflush(f); + fchmod(fileno(f), 0644); + if (ferror(f) || rename(path, "/run/udev/static_node-tags") < 0) { + r = -errno; + unlink("/run/udev/static_node-tags"); + unlink(path); + } + fclose(f); + } + + return r; } diff --git a/src/udev/udev.h b/src/udev/udev.h index d5f8cd7..6232793 100644 --- a/src/udev/udev.h +++ b/src/udev/udev.h @@ -72,7 +72,7 @@ struct udev_rules *udev_rules_new(struct udev *udev, int resolve_names); struct udev_rules *udev_rules_unref(struct udev_rules *rules); bool udev_rules_check_timestamp(struct udev_rules *rules); int udev_rules_apply_to_event(struct udev_rules *rules, struct udev_event *event, const sigset_t *sigmask); -void udev_rules_apply_static_dev_perms(struct udev_rules *rules); +int udev_rules_apply_static_dev_perms(struct udev_rules *rules); /* udev-event.c */ struct udev_event *udev_event_new(struct udev_device *dev); diff --git a/src/udev/udevd.c b/src/udev/udevd.c index c4127cd..285f9a0 100644 --- a/src/udev/udevd.c +++ b/src/udev/udevd.c @@ -1197,7 +1197,8 @@ int main(int argc, char *argv[]) } log_debug("set children_max to %u\n", children_max); - udev_rules_apply_static_dev_perms(rules); + if (udev_rules_apply_static_dev_perms(rules) < 0) + log_error("failed to apply permissions on static device nodes\n"); udev_list_node_init(&event_list); udev_list_node_init(&worker_list); -- 1.8.3.2