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 63BAFC4743C for ; Mon, 21 Jun 2021 17:57:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 50B92613B3 for ; Mon, 21 Jun 2021 17:57:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232132AbhFUR7u (ORCPT ); Mon, 21 Jun 2021 13:59:50 -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 S232452AbhFUR4y (ORCPT ); Mon, 21 Jun 2021 13:56:54 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 32340613B3; Mon, 21 Jun 2021 17:53:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624298014; bh=PlTTsjvsT8M0ZaanOfjdZwKOURjWLRmlWEa/RnIrFOo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VPa1+deWUZOUYe8ofx4bxvRG9kVh2goNcjMAdUzmxzS5yGzsW+ceGYC5bJg51k7Bs zjW4DkQN3wRIA5wG39jnLIW3xl5bPfSmJzlxyuItZ8pL2wFS84MOIP8T6mXE7Zgr3b a0A8pERgvPruv/5Ot7wRKFZK/jNLDlu3dlhFer6st0VrA0brzvxjfoMntx6u/HUvmv 18a55lxjw7PRPzWH/Vz4CY8c2MeXs6Nh5Igov3p0b1TlK9GndawpB55VbOsxJYDVpl wuYW+D80ZvoHOTUwWU+vl8avANuND3+BbtN2Heq3rQiSVy+6V8u2nQqu8vBTY2qCo3 S1VI0jKWqpBUg== 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 5.10 22/35] net: caif: fix memory leak in ldisc_open Date: Mon, 21 Jun 2021 13:52:47 -0400 Message-Id: <20210621175300.735437-22-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210621175300.735437-1-sashal@kernel.org> References: <20210621175300.735437-1-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 d025ea434933..39fbd0be179c 100644 --- a/drivers/net/caif/caif_serial.c +++ b/drivers/net/caif/caif_serial.c @@ -351,6 +351,7 @@ 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