res_pjsip_mwi: Fix segv caused by 16c7d8e74a9af13f98c3c22aa9c43ce39965f6b7

I forgot the new voicemail_extension wasn't a stringfield and didn't check
for NULL where I should have.

Change-Id: I029482d5c2ab72474838750461bd46b0809c90fb

diff --git a/res/res_pjsip_mwi.c b/res/res_pjsip_mwi.c
index 8735a7842899e7d5d9c68f82d5d62c688883520b..64d3c84eafb74296ddae6d6f1dffbed32fc50465 100644 (file)
--- a/res/res_pjsip_mwi.c
+++ b/res/res_pjsip_mwi.c
@@ -459,7 +459,8 @@ static struct ast_sip_aor *find_aor_for_resource(struct ast_sip_endpoint *endpoi
                        continue;
                }
 
-               if (!strcasecmp(check_aor->voicemail_extension, resource)) {
+               if (!ast_strlen_zero(check_aor->voicemail_extension)
+                       && !strcasecmp(check_aor->voicemail_extension, resource)) {
                        ast_debug(1, "Found an aor (%s) that matches voicemail_extension %s\n", aor_name, resource);
                        return check_aor;
                }