chan_rtp.c: Fix uninitialized memory crash.

unicast_rtp_request() could pass an uninitialized 'us' parameter to
ast_ouraddrfor().  If ast_ouraddrfor() returns an error then the 'us'
parameter may not get initialized.  Thus when the code tries to save the
'us' parameter to the local address we could try to copy a ridiculous
sized memory buffer and segfault.

* Made pass an initialized 'us' parameter to ast_ouraddrfor() and abort
the UnicastRTP channel request if it fails.

ASTERISK-26672

Change-Id: I1ef7a7c09f4da4f15dcb6de660d2bcac5f2a95c0

diff --git a/channels/chan_rtp.c b/channels/chan_rtp.c
index f1f4f05b93fced16bd7cbef1d95a711fa7d4c48e..d671706b252a4fba9261593bb3e224352591021a 100644 (file)
--- a/channels/chan_rtp.c
+++ b/channels/chan_rtp.c
@@ -316,7 +316,12 @@ static struct ast_channel *unicast_rtp_request(const char *type, struct ast_form
        engine_name = S_COR(ast_test_flag(&opts, OPT_RTP_ENGINE),
                opt_args[OPT_ARG_RTP_ENGINE], "asterisk");
 
-       ast_ouraddrfor(&address, &local_address);
+       ast_sockaddr_copy(&local_address, &address);
+       if (ast_ouraddrfor(&address, &local_address)) {
+               ast_log(LOG_ERROR, "Could not get our address for sending media to '%s'\n",
+                       args.destination);
+               goto failure;
+       }
        instance = ast_rtp_instance_new(engine_name, NULL, &local_address, NULL);
        if (!instance) {
                ast_log(LOG_ERROR,