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 DB526C48BC2 for ; Mon, 21 Jun 2021 18:05:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8428611CE for ; Mon, 21 Jun 2021 18:05:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234319AbhFUSHr (ORCPT ); Mon, 21 Jun 2021 14:07:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:46798 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232777AbhFUSD3 (ORCPT ); Mon, 21 Jun 2021 14:03:29 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 21F726140F; Mon, 21 Jun 2021 17:55:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624298129; bh=WH9gcW9Z1imxQPF+CrvliwExfi0LugZSfydWpHfsRJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OaZa7IJfIjL7dvBL+5YvikDJiWZCSiRhVAgm4B6A6rMyq5r+PAbh70a4dLKZtYtGm K3DO49O0Iv7OuLKXc2ieaI4HXEFp7PWpBXs1u5eSYb16dDXjYnYeCfWv2BXhwy4+Fq 7kVkby1cLwIJdvVufmGjO/PLrI1dqfyTOpXRYWSQINA8kRDobRjmp82B8XLuL9YC7R 5H7al2to4/wY0C/0tUZrh6K/btHCyxHcGJWkHZUXk0E+XZh8dt5mVed+Ctaig9drSp i/oLZxkDk8/AceDSfPMey8AbGP3yONTnvz39lRO+jj727qAxxdChRjTUJVCK5Y9Vrn +oT7GR6FRoxqg== 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 4.14 06/13] net: caif: fix memory leak in ldisc_open Date: Mon, 21 Jun 2021 13:55:12 -0400 Message-Id: <20210621175519.736255-6-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210621175519.736255-1-sashal@kernel.org> References: <20210621175519.736255-1-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: netdev@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 ce76ed50a1a2..1516d621e040 100644 --- a/drivers/net/caif/caif_serial.c +++ b/drivers/net/caif/caif_serial.c @@ -360,6 +360,7 @@ 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