prevent possible seg fault (issue #5502)

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/v1-0@6919 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/rtp.c b/rtp.c
index 79799fac914d2d79c702f26255429913a4728f90..c069b85bbb17f81c2dc1bf505ed4f913ab846489 100755 (executable)
--- a/rtp.c
+++ b/rtp.c
@@ -342,7 +342,7 @@ struct ast_frame *ast_rtcp_read(struct ast_rtp *rtp)
        unsigned int rtcpdata[1024];
        char iabuf[INET_ADDRSTRLEN];
        
-       if (!rtp->rtcp)
+       if (!rtp || !rtp->rtcp)
                return &null_frame;
 
        len = sizeof(sin);