From: Kevin Harwell <kharwell@digium.com>
Date: Thu, 30 Oct 2014 21:13:30 +0000 (+0000)
Subject: res_pjsip_exten_state: PJSIPShowSubscriptionsInbound causes crash
X-Git-Tag: 13.1.0-rc1~94
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c3b1d0df0d1c0cdf85d35241041714815cb6178a;p=thirdparty%2Fasterisk.git

res_pjsip_exten_state: PJSIPShowSubscriptionsInbound causes crash

Currently, it is possible for some subscriptions to get into a NULL state. When
this occurs and the PJSIPShowSubscriptionsInbound ami action is issued and a
device is subscribed for extension state then the associated subscription state
object can't be located.  The code then attempts to dereference a NULL object.
Added a NULL check to avoid the problem.

Reported by: John Bigelow
........

Merged revisions 426779 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/13@426780 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---

diff --git a/res/res_pjsip_exten_state.c b/res/res_pjsip_exten_state.c
index 6b8ee6c12f..332f45b3ac 100644
--- a/res/res_pjsip_exten_state.c
+++ b/res/res_pjsip_exten_state.c
@@ -457,6 +457,10 @@ static void to_ami(struct ast_sip_subscription *sub,
 	struct exten_state_subscription *exten_state_sub =
 		get_exten_state_sub(sub);
 
+	if (!exten_state_sub) {
+		return;
+	}
+
 	ast_str_append(buf, 0, "SubscriptionType: extension_state\r\n"
 		       "Extension: %s\r\nExtensionStates: %s\r\n",
 		       exten_state_sub->exten, ast_extension_state2str(