From 1ffb200c0e8642b7fb5c4f174e0064877f0c3d85 Mon Sep 17 00:00:00 2001
From: Terry Wilson <twilson@digium.com>
Date: Tue, 22 May 2012 16:23:19 +0000
Subject: [PATCH] Resolve crash in subscribing for MWI notifications
ASTOBJ_UNREF sets the variable to NULL after unreffing it, so the variable
should definitely not be used after that. To solve this in the two cases
that affect subscribing for MWI notifications, we instead save the ref
locally, and unref them in the error conditions.
(closes issue ASTERISK-19827)
Reported by: B. R
Review: https://reviewboard.asterisk.org/r/1940/
........
Merged revisions 367266 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........
Merged revisions 367267 from http://svn.asterisk.org/svn/asterisk/branches/10
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@367274 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---
channels/chan_sip.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index a84adeb75e..665daec1ad 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -12926,13 +12926,14 @@ static int __sip_subscribe_mwi_do(struct sip_subscription_mwi *mwi)
/* If we have no DNS manager let's do a lookup */
if (!mwi->dnsmgr) {
char transport[MAXHOSTNAMELEN];
+ struct sip_subscription_mwi *saved;
snprintf(transport, sizeof(transport), "_%s._%s", get_srv_service(mwi->transport), get_srv_protocol(mwi->transport));
mwi->us.ss.ss_family = get_address_family_filter(&bindaddr); /* Filter address family */
- ASTOBJ_REF(mwi); /* Add a ref for storing the mwi on the dnsmgr for updates */
- ast_dnsmgr_lookup_cb(mwi->hostname, &mwi->us, &mwi->dnsmgr, sip_cfg.srvlookup ? transport : NULL, on_dns_update_mwi, mwi);
+ saved = ASTOBJ_REF(mwi);
+ ast_dnsmgr_lookup_cb(mwi->hostname, &mwi->us, &mwi->dnsmgr, sip_cfg.srvlookup ? transport : NULL, on_dns_update_mwi, saved);
if (!mwi->dnsmgr) {
- ASTOBJ_UNREF(mwi, sip_subscribe_mwi_destroy); /* dnsmgr disabled, remove reference */
+ ASTOBJ_UNREF(saved, sip_subscribe_mwi_destroy); /* dnsmgr disabled, remove reference */
}
}
@@ -30932,10 +30933,12 @@ static void sip_send_all_registers(void)
static void sip_send_all_mwi_subscriptions(void)
{
ASTOBJ_CONTAINER_TRAVERSE(&submwil, 1, do {
+ struct sip_subscription_mwi *saved;
ASTOBJ_WRLOCK(iterator);
AST_SCHED_DEL(sched, iterator->resub);
- if ((iterator->resub = ast_sched_add(sched, 1, sip_subscribe_mwi_do, ASTOBJ_REF(iterator))) < 0) {
- ASTOBJ_UNREF(iterator, sip_subscribe_mwi_destroy);
+ saved = ASTOBJ_REF(iterator);
+ if ((iterator->resub = ast_sched_add(sched, 1, sip_subscribe_mwi_do, saved)) < 0) {
+ ASTOBJ_UNREF(saved, sip_subscribe_mwi_destroy);
}
ASTOBJ_UNLOCK(iterator);
} while (0));
--
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