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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5A13C433FE for ; Tue, 8 Feb 2022 13:16:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346836AbiBHNQh (ORCPT ); Tue, 8 Feb 2022 08:16:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58302 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237002AbiBHMjK (ORCPT ); Tue, 8 Feb 2022 07:39:10 -0500 Received: from mail-lj1-x22b.google.com (mail-lj1-x22b.google.com [IPv6:2a00:1450:4864:20::22b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99D6BC03FEC0 for ; Tue, 8 Feb 2022 04:39:09 -0800 (PST) Received: by mail-lj1-x22b.google.com with SMTP id a25so24232117lji.9 for ; Tue, 08 Feb 2022 04:39:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :references:from:in-reply-to:content-transfer-encoding; bh=HHy+eZQQMBsL1hI8tFLznDb4XcFfyuw3s8T6+48nfm8=; b=PZ0gNesx5cRn5kgwjQIk7wsoVsH9H1A/4CLxTNQyUFpZSzlVEB//gtDX+j4DbsKegH 26KWKRuKCw9RiObMPM/DlPjn5mRI4zhtkNGu3Mc9kRHriMCVyVqpc+SFhlNvuPgjxBBd uJnr43pI8P0fypehT/G1vmnbXZHrV+9H1oacBB2HztS1IxZqXOgf7XhQ/oP/g04Ku/on ghHg0s9sN9Z9j2NMsVSa5PxjamA6UUUlM0qfjHtvrkvhXHPbcW1lz2+R1SzBnOUem5Lz 4oM2RaY3QqYUs3eidJTF2Ed1sMs9ICF9QSZFk7PHosWkfhn/0z5Qb3GholKUZEHtFMD3 ovtw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:references:from:in-reply-to :content-transfer-encoding; bh=HHy+eZQQMBsL1hI8tFLznDb4XcFfyuw3s8T6+48nfm8=; b=f8roDgzQTmMg6i5uASII+oanuBDnFT2N+ginh1RkKNN/yTmSSbtazNONNcpdJAYbBq 1UKRWbZWgEyPM5ri6+y9S23f8vjVCEPfvl/FH9QU7qPup7+SphvcYiN7K4oIHRgn2sms ptufxxLrhSdv/Rs6Bph5WINKU7b1TlK1AQUlyKL2DtoqdSRX0LUM9dQifMhTHvRz8b8F Dl8NcMtLDcbV+ztQyeAyIjaOsNxjk6s5GXdYe4osSdrCtSQL47NANkMO7Tt+Tyx6BS8e VY9ltkYAdiorGFwdX2M0pXaxRtqPyZG1bemFXaNXrURnzul8FEgP5m9squzCyNfyk1xV oU9w== X-Gm-Message-State: AOAM530Xz3FuXcORW++cefOxxlrTI+aDIPG1G6gQ9sDB/JvTXCUah+Xa Sse3oFhCt7DAbia+UtZ42ELSjrnXw5kXXA== X-Google-Smtp-Source: ABdhPJz+pkAXcU1Voc6yQ9GOqOX+yzXIwELkhK4vUxSyWCDPSidyNSqQse9jaiASwRTaoc4jBwWNjw== X-Received: by 2002:a2e:b98a:: with SMTP id p10mr2726398ljp.195.1644323947798; Tue, 08 Feb 2022 04:39:07 -0800 (PST) Received: from [192.168.1.11] ([94.103.224.201]) by smtp.gmail.com with ESMTPSA id f15sm1906287lfg.230.2022.02.08.04.39.06 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 08 Feb 2022 04:39:07 -0800 (PST) Message-ID: Date: Tue, 8 Feb 2022 15:39:03 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [syzbot] WARNING in component_del Content-Language: en-US To: syzbot , dri-devel@lists.freedesktop.org, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, rafael@kernel.org, syzkaller-bugs@googlegroups.com References: <00000000000016f4ae05d5cec832@google.com> <0000000000001e4c2e05d77cfcbb@google.com> From: Pavel Skripkin In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Daniel, On 2/8/22 15:30, Daniel Vetter wrote: > On Mon, Feb 07, 2022 at 11:51:29PM -0800, syzbot wrote: >> syzbot has found a reproducer for the following issue on: >> >> HEAD commit: 555f3d7be91a Merge tag '5.17-rc3-ksmbd-server-fixes' of gi.. >> git tree: upstream >> console output: https://syzkaller.appspot.com/x/log.txt?x=130a0c2c700000 (*) >> kernel config: https://syzkaller.appspot.com/x/.config?x=266de9da75c71a45 >> dashboard link: https://syzkaller.appspot.com/bug?extid=60df062e1c41940cae0f >> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 >> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15880d84700000 >> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14de0c77b00000 >> >> IMPORTANT: if you fix the issue, please add the following tag to the commit: >> Reported-by: syzbot+60df062e1c41940cae0f@syzkaller.appspotmail.com > > From a quick grep usb seems to have indeed gained some component code, and > I'm not aware of any drm usb drivers using component. So I think this is > an usb issue, not a drm one. > It looks like missing error handling. syzbot injected allocation failure inside component_add(), but usb_hub_create_port_device() just prints warn message in case of component_add() failure (see log (*)) And then calling component_del() on non-added item causes WARN_ON() Can't prove my thoughts, since there is no repro :( With regards, Pavel Skripkin