From patchwork Tue Apr 26 08:21:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 566629 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D565BC43217 for ; Tue, 26 Apr 2022 08:43:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345631AbiDZIqo (ORCPT ); Tue, 26 Apr 2022 04:46:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346823AbiDZIpY (ORCPT ); Tue, 26 Apr 2022 04:45:24 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E043A90CF1; Tue, 26 Apr 2022 01:35:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 99298B81CFE; Tue, 26 Apr 2022 08:35:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DB3BEC385A4; Tue, 26 Apr 2022 08:35:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1650962148; bh=3aLdmpvxaChLzyHcYZwWLEm72qRpXWXyd7TlPmtCnCM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R0Dwtz/GFhSrIU5JxHSaVxx1zwPOrtb4MQFfxLv7EmXSwrtZWS12iH4MezHhdL/L0 h4e2Jo2qqBchjxGB1Z6h43QAA3nlDy1yaq+W/jnak6kVYhpux46xozP2ZX74e28KtP AAjw7b8ahrpqop/G7DDCukGLnLP3etJOFj9Pt1Cc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+2339c27f5c66c652843e@syzkaller.appspotmail.com, Oliver Hartkopp , Marc Kleine-Budde Subject: [PATCH 5.10 81/86] can: isotp: stop timeout monitoring when no first frame was sent Date: Tue, 26 Apr 2022 10:21:49 +0200 Message-Id: <20220426081743.553084500@linuxfoundation.org> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220426081741.202366502@linuxfoundation.org> References: <20220426081741.202366502@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Oliver Hartkopp commit d73497081710c876c3c61444445512989e102152 upstream. The first attempt to fix a the 'impossible' WARN_ON_ONCE(1) in isotp_tx_timer_handler() focussed on the identical CAN IDs created by the syzbot reproducer and lead to upstream fix/commit 3ea566422cbd ("can: isotp: sanitize CAN ID checks in isotp_bind()"). But this did not catch the root cause of the wrong tx.state in the tx_timer handler. In the isotp 'first frame' case a timeout monitoring needs to be started before the 'first frame' is send. But when this sending failed the timeout monitoring for this specific frame has to be disabled too. Otherwise the tx_timer is fired with the 'warn me' tx.state of ISOTP_IDLE. Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol") Link: https://lore.kernel.org/all/20220405175112.2682-1-socketcan@hartkopp.net Reported-by: syzbot+2339c27f5c66c652843e@syzkaller.appspotmail.com Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- net/can/isotp.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -864,6 +864,7 @@ static int isotp_sendmsg(struct socket * struct canfd_frame *cf; int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0; int wait_tx_done = (so->opt.flags & CAN_ISOTP_WAIT_TX_DONE) ? 1 : 0; + s64 hrtimer_sec = 0; int off; int err; @@ -962,7 +963,9 @@ static int isotp_sendmsg(struct socket * isotp_create_fframe(cf, so, ae); /* start timeout for FC */ - hrtimer_start(&so->txtimer, ktime_set(1, 0), HRTIMER_MODE_REL_SOFT); + hrtimer_sec = 1; + hrtimer_start(&so->txtimer, ktime_set(hrtimer_sec, 0), + HRTIMER_MODE_REL_SOFT); } /* send the first or only CAN frame */ @@ -975,6 +978,11 @@ static int isotp_sendmsg(struct socket * if (err) { pr_notice_once("can-isotp: %s: can_send_ret %d\n", __func__, err); + + /* no transmission -> no timeout monitoring */ + if (hrtimer_sec) + hrtimer_cancel(&so->txtimer); + goto err_out_drop; }