From: Jeff Peeler <jpeeler@digium.com>
Date: Tue, 1 Dec 2009 21:29:31 +0000 (+0000)
Subject: Fix crash with invalid frame data
X-Git-Tag: 1.4.28-rc1~11^2~10
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9405b9e2b756acb30727bff4e452cae64a8df3e3;p=thirdparty%2Fasterisk.git

Fix crash with invalid frame data

The crash was happening as a result of a frame containing an invalid data
pointer, but was set with data length of zero. The few times the issue was
reproduced it _seemed_ that the frame was queued properly, that is the data
pointer was set to NULL. I never could reproduce the crash so as a last resort
the crash has been fixed, but a check in __ast_read has been added to give as
much information about the source of problematic frames in the future.

(closes issue #16058)
Reported by: atis


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@231911 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---

diff --git a/main/channel.c b/main/channel.c
index 61a5a36088..dfd1062aca 100644
--- a/main/channel.c
+++ b/main/channel.c
@@ -2513,6 +2513,17 @@ static struct ast_frame *__ast_read(struct ast_channel *chan, int dropaudio)
 		ast_frame_dump(chan->name, f, "<<");
 	chan->fin = FRAMECOUNT_INC(chan->fin);
 
+	if (f && f->datalen == 0 && f->data) {
+		/* fix invalid pointer */
+		f->data = NULL;
+#ifdef AST_DEVMODE
+		ast_log(LOG_ERROR, "Found frame with src '%s' with datalen zero, but non-null data pointer!\n", f->src);
+		ast_frame_dump(chan->name, f, "<<");
+#else
+		ast_debug(3, "Found frame with src '%s' on channel '%s' with datalen zero, but non-null data pointer!\n", f->src, chan->name);
+#endif
+	}
+
 done:
 	ast_channel_unlock(chan);
 	return f;