Merged revisions 56684 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.2

........
r56684 | tilghman | 2007-02-25 08:38:03 -0600 (Sun, 25 Feb 2007) | 3 lines

Issue 9130 - If prev is the last item on the channel list, then evaluating
additional conditions (e.g. name prefix) will cause a NULL dereference.

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git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@56685 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/channel.c

@@ -997,7 +997,11 @@ static struct ast_channel *channel_find_locked(const struct ast_channel *prev,
 				if (c != prev)	/* not this one */
 					continue;
 				/* found, prepare to return c->next */
-				c = AST_LIST_NEXT(c, chan_list);
+				if ((c = AST_LIST_NEXT(c, chan_list)) == NULL) break;
+				/* If prev was the last item on the channel list, then we just
+				 * want to return NULL, instead of trying to deref NULL in the
+				 * next section.
+				 */
 			}
 			if (name) { /* want match by name */
 				if ((!namelen && strcasecmp(c->name, name)) ||