check array bounds when parsing arguments to AGI (issue #5868)

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.2@7557 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/res_agi.c

@@ -2016,9 +2016,8 @@ static int agi_exec_full(struct ast_channel *chan, void *data, int enhanced, int
 	ast_copy_string(buf, data, sizeof(buf));
 
 	memset(&agi, 0, sizeof(agi));
-        while ((stringp = strsep(&tmp, "|"))) {
+        while ((stringp = strsep(&tmp, "|")) && argc < MAX_ARGS - 1)
 		argv[argc++] = stringp;
-        }
 	argv[argc] = NULL;
 
 	LOCAL_USER_ADD(u);