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-rw-r--r--net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch421
1 files changed, 0 insertions, 421 deletions
diff --git a/net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch b/net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch
deleted file mode 100644
index 3d3c7b101d47..000000000000
--- a/net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch
+++ /dev/null
@@ -1,421 +0,0 @@
-From b35211fd58afcf430a0d95a243dc7a086d72b2b8 Mon Sep 17 00:00:00 2001
-From: Jaco Kroon <jaco@uls.co.za>
-Date: Fri, 21 May 2021 20:11:59 +0200
-Subject: [PATCH] Replacement patch for v13.
-
-Change-Id: I30236d7d7229f317c681fb7c6d7944d6108acd08
----
- funcs/func_lock.c | 234 +++++++++++++++++++++++++---------------------
- 1 file changed, 126 insertions(+), 108 deletions(-)
-
-diff --git a/funcs/func_lock.c b/funcs/func_lock.c
-index a006a574eb..c472504f52 100644
---- a/funcs/func_lock.c
-+++ b/funcs/func_lock.c
-@@ -44,6 +44,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
- #include "asterisk/linkedlists.h"
- #include "asterisk/astobj2.h"
- #include "asterisk/utils.h"
-+#include "asterisk/cli.h"
-
- /*** DOCUMENTATION
- <function name="LOCK" language="en_US">
-@@ -112,7 +113,6 @@ static AST_LIST_HEAD_STATIC(locklist, lock_frame);
- static void lock_free(void *data);
- static void lock_fixup(void *data, struct ast_channel *oldchan, struct ast_channel *newchan);
- static int unloading = 0;
--static pthread_t broker_tid = AST_PTHREADT_NULL;
-
- static const struct ast_datastore_info lock_info = {
- .type = "MUTEX",
-@@ -126,8 +126,8 @@ struct lock_frame {
- ast_cond_t cond;
- /*! count is needed so if a recursive mutex exits early, we know how many times to unlock it. */
- unsigned int count;
-- /*! Container of requesters for the named lock */
-- struct ao2_container *requesters;
-+ /*! Count of waiting of requesters for the named lock */
-+ unsigned int requesters;
- /*! who owns us */
- struct ast_channel *owner;
- /*! name of the lock */
-@@ -149,14 +149,19 @@ static void lock_free(void *data)
- while ((clframe = AST_LIST_REMOVE_HEAD(oldlist, list))) {
- /* Only unlock if we own the lock */
- if (clframe->channel == clframe->lock_frame->owner) {
-+ ast_mutex_lock(&clframe->lock_frame->mutex);
- clframe->lock_frame->count = 0;
- clframe->lock_frame->owner = NULL;
-+ ast_cond_signal(&clframe->lock_frame->cond);
-+ ast_mutex_unlock(&clframe->lock_frame->mutex);
- }
- ast_free(clframe);
- }
- AST_LIST_UNLOCK(oldlist);
- AST_LIST_HEAD_DESTROY(oldlist);
- ast_free(oldlist);
-+
-+ ast_module_unref(ast_module_info->self);
- }
-
- static void lock_fixup(void *data, struct ast_channel *oldchan, struct ast_channel *newchan)
-@@ -175,54 +180,11 @@ static void lock_fixup(void *data, struct ast_channel *oldchan, struct ast_chann
- if (clframe->lock_frame->owner == oldchan) {
- clframe->lock_frame->owner = newchan;
- }
-- /* We don't move requesters, because the thread stack is different */
- clframe->channel = newchan;
- }
- AST_LIST_UNLOCK(list);
- }
-
--static void *lock_broker(void *unused)
--{
-- struct lock_frame *frame;
-- struct timespec forever = { 1000000, 0 };
-- for (;;) {
-- int found_requester = 0;
--
-- /* Test for cancel outside of the lock */
-- pthread_testcancel();
-- AST_LIST_LOCK(&locklist);
--
-- AST_LIST_TRAVERSE(&locklist, frame, entries) {
-- if (ao2_container_count(frame->requesters)) {
-- found_requester++;
-- ast_mutex_lock(&frame->mutex);
-- if (!frame->owner) {
-- ast_cond_signal(&frame->cond);
-- }
-- ast_mutex_unlock(&frame->mutex);
-- }
-- }
--
-- AST_LIST_UNLOCK(&locklist);
-- pthread_testcancel();
--
-- /* If there are no requesters, then wait for a signal */
-- if (!found_requester) {
-- nanosleep(&forever, NULL);
-- } else {
-- sched_yield();
-- }
-- }
-- /* Not reached */
-- return NULL;
--}
--
--static int ast_channel_cmp_cb(void *obj, void *arg, int flags)
--{
-- struct ast_channel *chan = obj, *cmp_args = arg;
-- return strcasecmp(ast_channel_name(chan), ast_channel_name(cmp_args)) ? 0 : CMP_MATCH;
--}
--
- static int get_lock(struct ast_channel *chan, char *lockname, int trylock)
- {
- struct ast_datastore *lock_store = ast_channel_datastore_find(chan, &lock_info, NULL);
-@@ -234,7 +196,12 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock)
- struct timeval now;
-
- if (!lock_store) {
-- ast_debug(1, "Channel %s has no lock datastore, so we're allocating one.\n", ast_channel_name(chan));
-+ if (unloading) {
-+ ast_log(LOG_ERROR, "%sLOCK has no datastore and func_lock is unloading, failing.\n",
-+ trylock ? "TRY" : "");
-+ return -1;
-+ }
-+
- lock_store = ast_datastore_alloc(&lock_info, NULL);
- if (!lock_store) {
- ast_log(LOG_ERROR, "Unable to allocate new datastore. No locks will be obtained.\n");
-@@ -253,6 +220,9 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock)
- lock_store->data = list;
- AST_LIST_HEAD_INIT(list);
- ast_channel_datastore_add(chan, lock_store);
-+
-+ /* We cannot unload until this channel has released the lock_store */
-+ ast_module_ref(ast_module_info->self);
- } else
- list = lock_store->data;
-
-@@ -266,6 +236,9 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock)
-
- if (!current) {
- if (unloading) {
-+ ast_log(LOG_ERROR,
-+ "Lock doesn't exist whilst unloading. %sLOCK will fail.\n",
-+ trylock ? "TRY" : "");
- /* Don't bother */
- AST_LIST_UNLOCK(&locklist);
- return -1;
-@@ -292,17 +265,12 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock)
- AST_LIST_UNLOCK(&locklist);
- return -1;
- }
-- current->requesters = ao2_container_alloc_list(AO2_ALLOC_OPT_LOCK_MUTEX, 0,
-- NULL, ast_channel_cmp_cb);
-- if (!current->requesters) {
-- ast_mutex_destroy(&current->mutex);
-- ast_cond_destroy(&current->cond);
-- ast_free(current);
-- AST_LIST_UNLOCK(&locklist);
-- return -1;
-- }
- AST_LIST_INSERT_TAIL(&locklist, current, entries);
- }
-+ /* Add to requester list */
-+ ast_mutex_lock(&current->mutex);
-+ current->requesters++;
-+ ast_mutex_unlock(&current->mutex);
- AST_LIST_UNLOCK(&locklist);
-
- /* Found lock or created one - now find or create the corresponding link in the channel */
-@@ -315,7 +283,13 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock)
-
- if (!clframe) {
- if (unloading) {
-+ ast_log(LOG_ERROR,
-+ "Busy unloading. %sLOCK will fail.\n",
-+ trylock ? "TRY" : "");
- /* Don't bother */
-+ ast_mutex_lock(&current->mutex);
-+ current->requesters--;
-+ ast_mutex_unlock(&current->mutex);
- AST_LIST_UNLOCK(list);
- return -1;
- }
-@@ -324,6 +298,9 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock)
- ast_log(LOG_ERROR,
- "Unable to allocate channel lock frame. %sLOCK will fail.\n",
- trylock ? "TRY" : "");
-+ ast_mutex_lock(&current->mutex);
-+ current->requesters--;
-+ ast_mutex_unlock(&current->mutex);
- AST_LIST_UNLOCK(list);
- return -1;
- }
-@@ -339,44 +316,44 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock)
- * the same amount, before we'll release this one.
- */
- if (current->owner == chan) {
-+ /* We're not a requester, we already have it */
-+ ast_mutex_lock(&current->mutex);
-+ current->requesters--;
-+ ast_mutex_unlock(&current->mutex);
- current->count++;
- return 0;
- }
-
-- /* Okay, we have both frames, so now we need to try to lock.
-- *
-- * Locking order: always lock locklist first. We need the
-- * locklist lock because the broker thread counts whether
-- * there are requesters with the locklist lock held, and we
-- * need to hold it, so that when we send our signal, below,
-- * to wake up the broker thread, it definitely will see that
-- * a requester exists at that point in time. Otherwise, we
-- * could add to the requesters after it has already seen that
-- * that lock is unoccupied and wait forever for another signal.
-- */
-- AST_LIST_LOCK(&locklist);
-- ast_mutex_lock(&current->mutex);
-- /* Add to requester list */
-- ao2_link(current->requesters, chan);
-- pthread_kill(broker_tid, SIGURG);
-- AST_LIST_UNLOCK(&locklist);
--
- /* Wait up to three seconds from now for LOCK. */
- now = ast_tvnow();
- timeout.tv_sec = now.tv_sec + 3;
- timeout.tv_nsec = now.tv_usec * 1000;
-
-- if (!current->owner
-- || (!trylock
-- && !(res = ast_cond_timedwait(&current->cond, &current->mutex, &timeout)))) {
-- res = 0;
-+ ast_mutex_lock(&current->mutex);
-+
-+ res = 0;
-+ while (!trylock && !res && current->owner) {
-+ res = ast_cond_timedwait(&current->cond, &current->mutex, &timeout);
-+ }
-+ if (current->owner) {
-+ ast_log(LOG_ERROR, "%sLOCK failed to obtain lock %s.\n", trylock ? "TRY" : "",
-+ lockname);
-+ /* timeout;
-+ * trylock; or
-+ * cond_timedwait failed.
-+ *
-+ * either way, we fail to obtain the lock.
-+ */
-+ res = -1;
-+ } else {
- current->owner = chan;
- current->count++;
-- } else {
-- res = -1;
-+ res = 0;
- }
- /* Remove from requester list */
-- ao2_unlink(current->requesters, chan);
-+ current->requesters--;
-+ if (res && unloading)
-+ ast_cond_signal(&current->cond);
- ast_mutex_unlock(&current->mutex);
-
- return res;
-@@ -400,7 +377,7 @@ static int unlock_read(struct ast_channel *chan, const char *cmd, char *data, ch
- }
-
- if (!(list = lock_store->data)) {
-- ast_debug(1, "This should NEVER happen\n");
-+ ast_log(LOG_ERROR, "Datastore's data member is NULL ... this should be impossible.");
- ast_copy_string(buf, "0", len);
- return 0;
- }
-@@ -419,12 +396,17 @@ static int unlock_read(struct ast_channel *chan, const char *cmd, char *data, ch
-
- if (!clframe) {
- /* We didn't have this lock in the first place */
-+ ast_log(LOG_WARNING, "Attempting to UNLOCK(%s) - a lock this channel never owned.\n",
-+ data);
- ast_copy_string(buf, "0", len);
- return 0;
- }
-
- if (--clframe->lock_frame->count == 0) {
-+ ast_mutex_lock(&clframe->lock_frame->mutex);
- clframe->lock_frame->owner = NULL;
-+ ast_cond_signal(&clframe->lock_frame->cond);
-+ ast_mutex_unlock(&clframe->lock_frame->mutex);
- }
-
- ast_copy_string(buf, "1", len);
-@@ -455,6 +437,37 @@ static int trylock_read(struct ast_channel *chan, const char *cmd, char *data, c
- return 0;
- }
-
-+static char *handle_cli_locks_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
-+{
-+ int c = 0;
-+ struct lock_frame* current;
-+ switch (cmd) {
-+ case CLI_INIT:
-+ e->command = "locks show";
-+ e->usage =
-+ "Usage: locks show\n"
-+ " List all locks known to func_lock, along with their current status.\n";
-+ return NULL;
-+ case CLI_GENERATE:
-+ return NULL;
-+ }
-+
-+ ast_cli(a->fd, "func_lock locks:\n");
-+ ast_cli(a->fd, "%-40s Requesters Owner\n", "Name");
-+ AST_LIST_LOCK(&locklist);
-+ AST_LIST_TRAVERSE(&locklist, current, entries) {
-+ ast_mutex_lock(&current->mutex);
-+ ast_cli(a->fd, "%-40s %-10d %s\n", current->name, current->requesters,
-+ current->owner ? ast_channel_name(current->owner) : "(unlocked)");
-+ ast_mutex_unlock(&current->mutex);
-+ c++;
-+ }
-+ AST_LIST_UNLOCK(&locklist);
-+ ast_cli(a->fd, "%d total locks listed.\n", c);
-+
-+ return 0;
-+}
-+
- static struct ast_custom_function lock_function = {
- .name = "LOCK",
- .read = lock_read,
-@@ -473,6 +486,8 @@ static struct ast_custom_function unlock_function = {
- .read_max = 2,
- };
-
-+static struct ast_cli_entry cli_locks_show = AST_CLI_DEFINE(handle_cli_locks_show, "List func_lock locks.");
-+
- static int unload_module(void)
- {
- struct lock_frame *current;
-@@ -480,34 +495,43 @@ static int unload_module(void)
- /* Module flag */
- unloading = 1;
-
-+ /* Make it impossible for new requesters to be added
-+ * NOTE: channels could already be in get_lock() */
-+ ast_custom_function_unregister(&lock_function);
-+ ast_custom_function_unregister(&trylock_function);
-+
-+ ast_cli_unregister(&cli_locks_show);
-+
- AST_LIST_LOCK(&locklist);
- while ((current = AST_LIST_REMOVE_HEAD(&locklist, entries))) {
-- /* If any locks are currently in use, then we cannot unload this module */
-- if (current->owner || ao2_container_count(current->requesters)) {
-- /* Put it back */
-- AST_LIST_INSERT_HEAD(&locklist, current, entries);
-- AST_LIST_UNLOCK(&locklist);
-- unloading = 0;
-- return -1;
-+ int warned = 0;
-+ ast_mutex_lock(&current->mutex);
-+ while (current->owner || current->requesters) {
-+ if (!warned) {
-+ ast_log(LOG_WARNING, "Waiting for %d requesters for %s lock %s.\n",
-+ current->requesters, current->owner ? "locked" : "unlocked",
-+ current->name);
-+ warned = 1;
-+ }
-+ /* either the mutex is locked, or other parties are currently in get_lock,
-+ * we need to wait for all of those to clear first */
-+ ast_cond_wait(&current->cond, &current->mutex);
- }
-+ ast_mutex_unlock(&current->mutex);
-+ /* At this point we know:
-+ * 1. the lock has been released,
-+ * 2. there are no requesters (nor should any be able to sneak in).
-+ */
- ast_mutex_destroy(&current->mutex);
-- ao2_ref(current->requesters, -1);
-+ ast_cond_destroy(&current->cond);
- ast_free(current);
- }
-+ AST_LIST_UNLOCK(&locklist);
-+ AST_LIST_HEAD_DESTROY(&locklist);
-
-- /* No locks left, unregister functions */
-- ast_custom_function_unregister(&lock_function);
-- ast_custom_function_unregister(&trylock_function);
-+ /* At this point we can safely stop access to UNLOCK */
- ast_custom_function_unregister(&unlock_function);
-
-- if (broker_tid != AST_PTHREADT_NULL) {
-- pthread_cancel(broker_tid);
-- pthread_kill(broker_tid, SIGURG);
-- pthread_join(broker_tid, NULL);
-- }
--
-- AST_LIST_UNLOCK(&locklist);
--
- return 0;
- }
-
-@@ -516,13 +540,7 @@ static int load_module(void)
- int res = ast_custom_function_register_escalating(&lock_function, AST_CFE_READ);
- res |= ast_custom_function_register_escalating(&trylock_function, AST_CFE_READ);
- res |= ast_custom_function_register_escalating(&unlock_function, AST_CFE_READ);
--
-- if (ast_pthread_create_background(&broker_tid, NULL, lock_broker, NULL)) {
-- ast_log(LOG_ERROR, "Failed to start lock broker thread. Unloading func_lock module.\n");
-- broker_tid = AST_PTHREADT_NULL;
-- unload_module();
-- return AST_MODULE_LOAD_DECLINE;
-- }
-+ res |= ast_cli_register(&cli_locks_show);
-
- return res;
- }
---
-2.26.3
-