From: Corey Farrell <git@cfware.com>
Date: Tue, 28 Oct 2014 20:55:04 +0000 (+0000)
Subject: res_fax: Resolve T38 gateway frame leak.
X-Git-Tag: 12.7.0-rc1~22
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6c96ec7379761f7b5fe3776239dcd5f0d82d9625;p=thirdparty%2Fasterisk.git

res_fax: Resolve T38 gateway frame leak.

When frames are translated by a fax gateway they need to be freed.  The
existing call to ast_frfree was unreachable.  This change reorganizes
fax_gateway_framehook to ensure that ast_frfree is called when needed.

ASTERISK-24457 #close
Reported by: Corey Farrell
Review: https://reviewboard.asterisk.org/r/4115/
........

Merged revisions 426527 from http://svn.asterisk.org/svn/asterisk/branches/11


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/12@426528 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---

diff --git a/res/res_fax.c b/res/res_fax.c
index 4e58e89ab4..a233eef9b5 100644
--- a/res/res_fax.c
+++ b/res/res_fax.c
@@ -3233,25 +3233,25 @@ static struct ast_frame *fax_gateway_framehook(struct ast_channel *chan, struct
 
 	/* in gateway mode, gateway some packets */
 	if (gateway->t38_state == T38_STATE_NEGOTIATED) {
+		struct ast_trans_pvt *readtrans;
 		/* framehooks are called in __ast_read() before frame format
 		 * translation is done, so we need to translate here */
-		if ((f->frametype == AST_FRAME_VOICE) && (f->subclass.format.id != AST_FORMAT_SLINEAR)) {
-			if (ast_channel_readtrans(active) && (f = ast_translate(ast_channel_readtrans(active), f, 1)) == NULL) {
+		if ((f->frametype == AST_FRAME_VOICE) && (f->subclass.format.id != AST_FORMAT_SLINEAR)
+			&& (readtrans = ast_channel_readtrans(active))) {
+			if ((f = ast_translate(readtrans, f, 1)) == NULL) {
 				f = &ast_null_frame;
 				return f;
 			}
-		}
-
-		/* XXX we ignore the return value here, perhaps we should
-		 * disable the gateway if a write fails. I am not sure how a
-		 * write would fail, or even if a failure would be fatal so for
-		 * now we'll just ignore the return value. */
-		gateway->s->tech->write(gateway->s, f);
-		if ((f->frametype == AST_FRAME_VOICE) && (f->subclass.format.id != AST_FORMAT_SLINEAR) && ast_channel_readtrans(active)) {
-			/* Only free the frame if we translated / duplicated it - otherwise,
-			 * let whatever is outside the frame hook do it */
+			/* XXX we ignore the return value here, perhaps we should
+			 * disable the gateway if a write fails. I am not sure how a
+			 * write would fail, or even if a failure would be fatal so for
+			 * now we'll just ignore the return value. */
+			gateway->s->tech->write(gateway->s, f);
 			ast_frfree(f);
+		} else {
+			gateway->s->tech->write(gateway->s, f);
 		}
+
 		f = &ast_null_frame;
 		return f;
 	}