From mboxrd@z Thu Jan 1 00:00:00 1970 From: mwilck@suse.com Subject: [PATCH v2 11/21] libmultipath: protect racy libdevmapper calls with a mutex Date: Thu, 24 Sep 2020 15:37:06 +0200 Message-ID: <20200924133716.14120-12-mwilck@suse.com> References: <20200924133716.14120-1-mwilck@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20200924133716.14120-1-mwilck@suse.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Christophe Varoqui , Benjamin Marzinski Cc: lixiaokeng@huawei.com, dm-devel@redhat.com, Martin Wilck List-Id: dm-devel.ids From: Martin Wilck dm_udev_wait() and dm_task_run() may access global / static state in libdevmapper. They need to be protected by a lock in in our multithreaded library. Cc: lixiaokeng@huawei.com Reviewed-by: Benjamin Marzinski Signed-off-by: Martin Wilck --- libmultipath/devmapper.c | 73 +++++++++++++++++++------------ libmultipath/devmapper.h | 2 + libmultipath/libmultipath.version | 6 +++ libmultipath/util.c | 5 +++ libmultipath/util.h | 1 + multipathd/dmevents.c | 2 +- multipathd/waiter.c | 2 +- 7 files changed, 62 insertions(+), 29 deletions(-) diff --git a/libmultipath/devmapper.c b/libmultipath/devmapper.c index 08aa09f..2e3ae8a 100644 --- a/libmultipath/devmapper.c +++ b/libmultipath/devmapper.c @@ -42,6 +42,7 @@ static unsigned int dm_mpath_target_version[3] = { INVALID_VERSION, }; static pthread_once_t dm_initialized = PTHREAD_ONCE_INIT; static pthread_once_t versions_initialized = PTHREAD_ONCE_INIT; +static pthread_mutex_t libmp_dm_lock = PTHREAD_MUTEX_INITIALIZER; static int dm_conf_verbosity; @@ -59,16 +60,34 @@ static inline int dm_task_set_cookie(struct dm_task *dmt, uint32_t *c, int a) return 1; } -void dm_udev_wait(unsigned int c) +static void libmp_udev_wait(unsigned int c) { } -void dm_udev_set_sync_support(int c) +static void dm_udev_set_sync_support(int c) { } - +#else +static void libmp_udev_wait(unsigned int c) +{ + pthread_mutex_lock(&libmp_dm_lock); + pthread_cleanup_push(cleanup_mutex, &libmp_dm_lock); + dm_udev_wait(c); + pthread_cleanup_pop(1); +} #endif +int libmp_dm_task_run(struct dm_task *dmt) +{ + int r; + + pthread_mutex_lock(&libmp_dm_lock); + pthread_cleanup_push(cleanup_mutex, &libmp_dm_lock); + r = dm_task_run(dmt); + pthread_cleanup_pop(1); + return r; +} + __attribute__((format(printf, 4, 5))) static void dm_write_log (int level, const char *file, int line, const char *f, ...) { @@ -196,7 +215,7 @@ static int dm_tgt_version (unsigned int *version, char *str) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(2, DM_DEVICE_LIST_VERSIONS, dmt); condlog(0, "Can not communicate with kernel DM"); goto out; @@ -380,12 +399,12 @@ dm_simplecmd (int task, const char *name, int no_flush, int need_sync, uint16_t DM_UDEV_DISABLE_LIBRARY_FALLBACK | udev_flags)) goto out; - r = dm_task_run (dmt); + r = libmp_dm_task_run (dmt); if (!r) dm_log_error(2, task, dmt); if (udev_wait_flag) - dm_udev_wait(cookie); + libmp_udev_wait(cookie); out: dm_task_destroy (dmt); return r; @@ -472,12 +491,12 @@ dm_addmap (int task, const char *target, struct multipath *mpp, !dm_task_set_cookie(dmt, &cookie, udev_flags)) goto freeout; - r = dm_task_run (dmt); + r = libmp_dm_task_run (dmt); if (!r) dm_log_error(2, task, dmt); if (task == DM_DEVICE_CREATE) - dm_udev_wait(cookie); + libmp_udev_wait(cookie); freeout: if (prefixed_uuid) FREE(prefixed_uuid); @@ -587,7 +606,7 @@ do_get_info(const char *name, struct dm_info *info) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_INFO, dmt); goto out; } @@ -628,7 +647,7 @@ int dm_get_map(const char *name, unsigned long long *size, char *outparams) dm_task_no_open_count(dmt); errno = 0; - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_TABLE, dmt); if (dm_task_get_errno(dmt) == ENXIO) r = DMP_NOT_FOUND; @@ -670,7 +689,7 @@ dm_get_prefixed_uuid(const char *name, char *uuid, int uuid_len) if (!dm_task_set_name (dmt, name)) goto uuidout; - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_INFO, dmt); goto uuidout; } @@ -741,7 +760,7 @@ int dm_get_status(const char *name, char *outstatus) dm_task_no_open_count(dmt); errno = 0; - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_STATUS, dmt); if (dm_task_get_errno(dmt) == ENXIO) r = DMP_NOT_FOUND; @@ -794,7 +813,7 @@ int dm_type(const char *name, char *type) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_TABLE, dmt); goto out; } @@ -838,7 +857,7 @@ int dm_is_mpath(const char *name) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_TABLE, dmt); goto out_task; } @@ -902,7 +921,7 @@ dm_map_present_by_uuid(const char *uuid) if (!dm_task_set_uuid(dmt, prefixed_uuid)) goto out_task; - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_INFO, dmt); goto out_task; } @@ -948,7 +967,7 @@ dm_get_opencount (const char * mapname) if (!dm_task_set_name(dmt, mapname)) goto out; - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_INFO, dmt); goto out; } @@ -1108,7 +1127,7 @@ int dm_flush_maps (int need_suspend, int retries) dm_task_no_open_count(dmt); - if (!dm_task_run (dmt)) { + if (!libmp_dm_task_run (dmt)) { dm_log_error(3, DM_DEVICE_LIST, dmt); goto out; } @@ -1154,7 +1173,7 @@ dm_message(const char * mapname, char * message) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(2, DM_DEVICE_TARGET_MSG, dmt); goto out; } @@ -1274,7 +1293,7 @@ dm_get_maps (vector mp) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_LIST, dmt); goto out; } @@ -1359,7 +1378,7 @@ dm_mapname(int major, int minor) * daemon uev_trigger -> uev_add_map */ while (--loop) { - r = dm_task_run(dmt); + r = libmp_dm_task_run(dmt); if (r) break; @@ -1404,7 +1423,7 @@ do_foreach_partmaps (const char * mapname, dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_LIST, dmt); goto out; } @@ -1639,11 +1658,11 @@ dm_rename (const char * old, char * new, char *delim, int skip_kpartx) if (!dm_task_set_cookie(dmt, &cookie, udev_flags)) goto out; - r = dm_task_run(dmt); + r = libmp_dm_task_run(dmt); if (!r) dm_log_error(2, DM_DEVICE_RENAME, dmt); - dm_udev_wait(cookie); + libmp_udev_wait(cookie); out: dm_task_destroy(dmt); @@ -1685,7 +1704,7 @@ int dm_reassign_table(const char *name, char *old, char *new) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_TABLE, dmt); goto out; } @@ -1718,7 +1737,7 @@ int dm_reassign_table(const char *name, char *old, char *new) if (modified) { dm_task_no_open_count(reload_dmt); - if (!dm_task_run(reload_dmt)) { + if (!libmp_dm_task_run(reload_dmt)) { dm_log_error(3, DM_DEVICE_RELOAD, reload_dmt); condlog(3, "%s: failed to reassign targets", name); goto out_reload; @@ -1765,7 +1784,7 @@ int dm_reassign(const char *mapname) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_DEPS, dmt); goto out; } @@ -1833,7 +1852,7 @@ int dm_setgeometry(struct multipath *mpp) goto out; } - r = dm_task_run(dmt); + r = libmp_dm_task_run(dmt); if (!r) dm_log_error(3, DM_DEVICE_SET_GEOMETRY, dmt); out: diff --git a/libmultipath/devmapper.h b/libmultipath/devmapper.h index c8b37e1..158057e 100644 --- a/libmultipath/devmapper.h +++ b/libmultipath/devmapper.h @@ -89,6 +89,8 @@ enum { MULTIPATH_VERSION }; int libmp_get_version(int which, unsigned int version[3]); +struct dm_task; +int libmp_dm_task_run(struct dm_task *dmt); #define dm_log_error(lvl, cmd, dmt) \ condlog(lvl, "%s: libdm task=%d error: %s", __func__, \ diff --git a/libmultipath/libmultipath.version b/libmultipath/libmultipath.version index 5699a0b..0a96010 100644 --- a/libmultipath/libmultipath.version +++ b/libmultipath/libmultipath.version @@ -212,3 +212,9 @@ global: local: *; }; + +LIBMULTIPATH_0.8.4.2 { +global: + libmp_dm_task_run; + cleanup_mutex; +} LIBMULTIPATH_0.8.4.1; diff --git a/libmultipath/util.c b/libmultipath/util.c index 66cd721..41da6ce 100644 --- a/libmultipath/util.c +++ b/libmultipath/util.c @@ -409,6 +409,11 @@ void cleanup_free_ptr(void *arg) free(*p); } +void cleanup_mutex(void *arg) +{ + pthread_mutex_unlock(arg); +} + struct bitfield *alloc_bitfield(unsigned int maxbit) { unsigned int n; diff --git a/libmultipath/util.h b/libmultipath/util.h index c1ae878..b8481af 100644 --- a/libmultipath/util.h +++ b/libmultipath/util.h @@ -49,6 +49,7 @@ int should_exit(void); void close_fd(void *arg); void cleanup_free_ptr(void *arg); +void cleanup_mutex(void *arg); struct scandir_result { struct dirent **di; diff --git a/multipathd/dmevents.c b/multipathd/dmevents.c index fc97c8a..b561cbf 100644 --- a/multipathd/dmevents.c +++ b/multipathd/dmevents.c @@ -156,7 +156,7 @@ static int dm_get_events(void) dm_task_no_open_count(dmt); - if (!dm_task_run(dmt)) { + if (!libmp_dm_task_run(dmt)) { dm_log_error(3, DM_DEVICE_LIST, dmt); goto fail; } diff --git a/multipathd/waiter.c b/multipathd/waiter.c index 16fbdc8..620bfa7 100644 --- a/multipathd/waiter.c +++ b/multipathd/waiter.c @@ -118,7 +118,7 @@ static int waiteventloop (struct event_thread *waiter) pthread_sigmask(SIG_UNBLOCK, &set, &oldset); pthread_testcancel(); - r = dm_task_run(waiter->dmt); + r = libmp_dm_task_run(waiter->dmt); if (!r) dm_log_error(2, DM_DEVICE_WAITEVENT, waiter->dmt); pthread_testcancel(); -- 2.28.0