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=-13.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 autolearn=ham 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 34103C432C0 for ; Thu, 28 Nov 2019 11:10:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C29521774 for ; Thu, 28 Nov 2019 11:10:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726733AbfK1LKz (ORCPT ); Thu, 28 Nov 2019 06:10:55 -0500 Received: from mx2.suse.de ([195.135.220.15]:52730 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726582AbfK1LKz (ORCPT ); Thu, 28 Nov 2019 06:10:55 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id D2AD6AD10; Thu, 28 Nov 2019 11:10:52 +0000 (UTC) Message-ID: <1574939450.21204.7.camel@suse.com> Subject: Re: KASAN: use-after-free Read in si470x_int_in_callback (2) From: Oliver Neukum To: syzbot , andreyknvl@google.com, hverkuil@xs4all.nl, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-usb@vger.kernel.org, mchehab@kernel.org, syzkaller-bugs@googlegroups.com Date: Thu, 28 Nov 2019 12:10:50 +0100 In-Reply-To: <000000000000f47f0b0595307ddc@google.com> References: <000000000000f47f0b0595307ddc@google.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Freitag, den 18.10.2019, 07:53 -0700 schrieb syzbot: > Hello, > > syzbot found the following crash on: > > HEAD commit: 22be26f7 usb-fuzzer: main usb gadget fuzzer driver > git tree: https://github.com/google/kasan.git usb-fuzzer > console output: https://syzkaller.appspot.com/x/log.txt?x=102b65cf600000 > kernel config: https://syzkaller.appspot.com/x/.config?x=387eccb7ac68ec5 > dashboard link: https://syzkaller.appspot.com/bug?extid=9ca7a12fd736d93e0232 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=143b9060e00000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15d3b94b600000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+9ca7a12fd736d93e0232@syzkaller.appspotmail.com JUST FOR DEBUGGING #syz test: https://github.com/google/kasan.git 22be26f7 >From 6e4c324c34b2fead2bdd1bc1274bd2e978df2be5 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Mon, 18 Nov 2019 14:41:51 +0100 Subject: [PATCH] si470x: prevent resubmission Starting IO to a device is not necessarily a NOP in every error case. So we need to terminate all IO in every case of probe failure and disconnect with absolute certainty. Signed-off-by: Oliver Neukum --- drivers/media/radio/si470x/radio-si470x-usb.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/media/radio/si470x/radio-si470x-usb.c b/drivers/media/radio/si470x/radio-si470x-usb.c index fedff68d8c49..3a3c539ee39a 100644 --- a/drivers/media/radio/si470x/radio-si470x-usb.c +++ b/drivers/media/radio/si470x/radio-si470x-usb.c @@ -373,6 +373,7 @@ static void si470x_int_in_callback(struct urb *urb) if (urb->status == -ENOENT || urb->status == -ECONNRESET || urb->status == -ESHUTDOWN) { + printk(KERN_ERR"Int URB killed\n"); return; } else { dev_warn(&radio->intf->dev, @@ -463,6 +464,7 @@ static void si470x_int_in_callback(struct urb *urb) /* Resubmit if we're still running. */ if (radio->int_in_running && radio->usbdev) { retval = usb_submit_urb(radio->int_in_urb, GFP_ATOMIC); + printk(KERN_ERR"In resubmit code path with result %d\n", retval); if (retval) { dev_warn(&radio->intf->dev, "resubmitting urb failed (%d)", retval); @@ -542,6 +544,8 @@ static int si470x_start_usb(struct si470x_device *radio) radio->int_in_running = 0; } radio->status_rssi_auto_update = radio->int_in_running; + if (retval < 0) + return retval; /* start radio */ retval = si470x_start(radio); @@ -734,7 +738,8 @@ static int si470x_usb_driver_probe(struct usb_interface *intf, /* start radio */ retval = si470x_start_usb(radio); if (retval < 0) - goto err_buf; + /* the urb may be running even after an error */ + goto err_all; /* set initial frequency */ si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */ @@ -749,7 +754,7 @@ static int si470x_usb_driver_probe(struct usb_interface *intf, return 0; err_all: - usb_kill_urb(radio->int_in_urb); + usb_poison_urb(radio->int_in_urb); err_buf: kfree(radio->buffer); err_ctrl: @@ -824,7 +829,7 @@ static void si470x_usb_driver_disconnect(struct usb_interface *intf) mutex_lock(&radio->lock); v4l2_device_disconnect(&radio->v4l2_dev); video_unregister_device(&radio->videodev); - usb_kill_urb(radio->int_in_urb); + usb_poison_urb(radio->int_in_urb); usb_set_intfdata(intf, NULL); mutex_unlock(&radio->lock); v4l2_device_put(&radio->v4l2_dev); -- 2.16.4