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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B530CC4332F for ; Mon, 25 Oct 2021 19:35:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9502A610A1 for ; Mon, 25 Oct 2021 19:35:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236162AbhJYThu (ORCPT ); Mon, 25 Oct 2021 15:37:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:53486 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236573AbhJYTe5 (ORCPT ); Mon, 25 Oct 2021 15:34:57 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 43166610C8; Mon, 25 Oct 2021 19:31:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1635190287; bh=zdKgZyh2zyMlaaeqeVL+2k6iSsVp9MWQg7DLL/SSnOc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Pynn3FZhZLaAlyqLKPeI81J60Z+NcQuqrLWDlJWayxsnbxYwwhrG5+8MbZ2hXEi9S 9kuA0CDDu2EEFu7x8GoqpH1lJvyvB+602BigNPtKhoLjHMfguw7EWRw0U/lpRHXup6 g/YYDoctNUPsnWgdL0PszbyRCWqDIcfii7/0+7zE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+78bab6958a614b0c80b9@syzkaller.appspotmail.com, Ziyang Xuan , Oliver Hartkopp , Marc Kleine-Budde Subject: [PATCH 5.10 38/95] can: isotp: isotp_sendmsg(): add result check for wait_event_interruptible() Date: Mon, 25 Oct 2021 21:14:35 +0200 Message-Id: <20211025191002.297023883@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211025190956.374447057@linuxfoundation.org> References: <20211025190956.374447057@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Ziyang Xuan commit 9acf636215a6ce9362fe618e7da4913b8bfe84c8 upstream. Using wait_event_interruptible() to wait for complete transmission, but do not check the result of wait_event_interruptible() which can be interrupted. It will result in TX buffer has multiple accessors and the later process interferes with the previous process. Following is one of the problems reported by syzbot. ============================================================= WARNING: CPU: 0 PID: 0 at net/can/isotp.c:840 isotp_tx_timer_handler+0x2e0/0x4c0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.13.0-rc7+ #68 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014 RIP: 0010:isotp_tx_timer_handler+0x2e0/0x4c0 Call Trace: ? isotp_setsockopt+0x390/0x390 __hrtimer_run_queues+0xb8/0x610 hrtimer_run_softirq+0x91/0xd0 ? rcu_read_lock_sched_held+0x4d/0x80 __do_softirq+0xe8/0x553 irq_exit_rcu+0xf8/0x100 sysvec_apic_timer_interrupt+0x9e/0xc0 asm_sysvec_apic_timer_interrupt+0x12/0x20 Add result check for wait_event_interruptible() in isotp_sendmsg() to avoid multiple accessers for tx buffer. Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol") Link: https://lore.kernel.org/all/10ca695732c9dd267c76a3c30f37aefe1ff7e32f.1633764159.git.william.xuanziyang@huawei.com Cc: stable@vger.kernel.org Reported-by: syzbot+78bab6958a614b0c80b9@syzkaller.appspotmail.com Signed-off-by: Ziyang Xuan Acked-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- net/can/isotp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -863,7 +863,9 @@ static int isotp_sendmsg(struct socket * return -EAGAIN; /* wait for complete transmission of current pdu */ - wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE); + err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE); + if (err) + return err; } if (!size || size > MAX_MSG_LENGTH)