From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D44CAC4743C for ; Mon, 21 Jun 2021 17:53:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BAA5B613B2 for ; Mon, 21 Jun 2021 17:53:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232199AbhFURzj (ORCPT ); Mon, 21 Jun 2021 13:55:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:39160 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232152AbhFURyu (ORCPT ); Mon, 21 Jun 2021 13:54:50 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id EB73E61206; Mon, 21 Jun 2021 17:52:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624297955; bh=BaNvhATeEufCxlq19nIJTaVOVFK2DRAYVIjsRxIn9Hw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Fd+hvYBr+0b3ffb91YDQmZBoigYaI92Jby2vB5s91efGf8bch/wexAehmMLJlVqZC tc3t+/JTC0a8Mp0Pmj4pClOpJvaXb3ZVDQDlEWcvz/dAXWweIxfWSr76ajpyrijfob us5pvffeODJnaz7ZoZnMiqsQvb5qCl5RN1Wnws9a+Jd8acS9mZtMeudT1A2Z0+IQZe frLewLubvql9fiO1htEJe3jBREKcNI0xuTAHVBcZxG9nzYRy+hOnlMZQ/0MHlDGRo7 lJtogKOq92hGucv6xy0q9FqABTV2rwBq8emSrGoaCP94yqpFN6HhPFoQ1sN+yVa0bt ZIA+a7H1AgOUw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Pavel Skripkin , syzbot+f303e045423e617d2cad@syzkaller.appspotmail.com, "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.12 23/39] net: caif: fix memory leak in ldisc_open Date: Mon, 21 Jun 2021 13:51:39 -0400 Message-Id: <20210621175156.735062-23-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210621175156.735062-1-sashal@kernel.org> References: <20210621175156.735062-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pavel Skripkin [ Upstream commit 58af3d3d54e87bfc1f936e16c04ade3369d34011 ] Syzbot reported memory leak in tty_init_dev(). The problem was in unputted tty in ldisc_open() static int ldisc_open(struct tty_struct *tty) { ... ser->tty = tty_kref_get(tty); ... result = register_netdevice(dev); if (result) { rtnl_unlock(); free_netdev(dev); return -ENODEV; } ... } Ser pointer is netdev private_data, so after free_netdev() this pointer goes away with unputted tty reference. So, fix it by adding tty_kref_put() before freeing netdev. Reported-and-tested-by: syzbot+f303e045423e617d2cad@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/caif/caif_serial.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c index 9f30748da4ab..8c38f224becb 100644 --- a/drivers/net/caif/caif_serial.c +++ b/drivers/net/caif/caif_serial.c @@ -350,6 +350,7 @@ static int ldisc_open(struct tty_struct *tty) rtnl_lock(); result = register_netdevice(dev); if (result) { + tty_kref_put(tty); rtnl_unlock(); free_netdev(dev); return -ENODEV; -- 2.30.2