From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756247Ab0IRTCd (ORCPT ); Sat, 18 Sep 2010 15:02:33 -0400 Received: from kroah.org ([198.145.64.141]:51267 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754811Ab0IRTBc (ORCPT ); Sat, 18 Sep 2010 15:01:32 -0400 X-Mailbox-Line: From gregkh@clark.site Sat Sep 18 11:59:55 2010 Message-Id: <20100918185955.815808265@clark.site> User-Agent: quilt/0.48-11.2 Date: Sat, 18 Sep 2010 11:57:59 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Takashi Iwai Subject: [035/123] ALSA: seq/oss - Fix double-free at error path of snd_seq_oss_open() References: <20100918185724.290702750@clark.site> Content-Disposition: inline; filename=alsa-seq-oss-fix-double-free-at-error-path-of-snd_seq_oss_open.patch In-Reply-To: <20100918190024.GA14388@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Takashi Iwai commit 27f7ad53829f79e799a253285318bff79ece15bd upstream. The error handling in snd_seq_oss_open() has several bad codes that do dereferecing released pointers and double-free of kmalloc'ed data. The object dp is release in free_devinfo() that is called via private_free callback. The rest shouldn't touch this object any more. The patch changes delete_port() to call kfree() in any case, and gets rid of unnecessary calls of destructors in snd_seq_oss_open(). Fixes CVE-2010-3080. Reported-and-tested-by: Tavis Ormandy Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/core/seq/oss/seq_oss_init.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/sound/core/seq/oss/seq_oss_init.c +++ b/sound/core/seq/oss/seq_oss_init.c @@ -280,13 +280,10 @@ snd_seq_oss_open(struct file *file, int return 0; _error: - snd_seq_oss_writeq_delete(dp->writeq); - snd_seq_oss_readq_delete(dp->readq); snd_seq_oss_synth_cleanup(dp); snd_seq_oss_midi_cleanup(dp); - delete_port(dp); delete_seq_queue(dp->queue); - kfree(dp); + delete_port(dp); return rc; } @@ -349,8 +346,10 @@ create_port(struct seq_oss_devinfo *dp) static int delete_port(struct seq_oss_devinfo *dp) { - if (dp->port < 0) + if (dp->port < 0) { + kfree(dp); return 0; + } debug_printk(("delete_port %i\n", dp->port)); return snd_seq_event_port_detach(dp->cseq, dp->port);