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=-5.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,LOTS_OF_MONEY,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS 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 F0E81C33C9E for ; Tue, 7 Jan 2020 08:17:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CFE5C207FF for ; Tue, 7 Jan 2020 08:17:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727677AbgAGIRK (ORCPT ); Tue, 7 Jan 2020 03:17:10 -0500 Received: from mail-io1-f70.google.com ([209.85.166.70]:36018 "EHLO mail-io1-f70.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727211AbgAGIRK (ORCPT ); Tue, 7 Jan 2020 03:17:10 -0500 Received: by mail-io1-f70.google.com with SMTP id 144so32956983iou.3 for ; Tue, 07 Jan 2020 00:17:09 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=sWRGtZyhrTa5cnofeyFrm2ZXt4tjqGK52iR9mR6FDmI=; b=kANnr7H/ux2Ku6Zb9uDsDqNzsfsFUamjE4YcShZOPamYZO3OKlFewrXDF0SjhWbJ0y E2240X/ZNPSkjrFcqYtNBKcHDqQ2cRI9EvLEQxwJ7n6q2DNefvfGRC/7veUvLwCLG37B hStPp+UfC8b9+rSqEFnBIihUyRsnUoopHCx0kMAG5IlL+PwdxE48sS+XGD+EuCkl9niQ /eYMOWAKfjzEqSDREROuYGYzdvb9kh8JqHWQ97vUgVABisRwdSxDktXKzlFFZOzjtTjE hZQcn1Cl1oMo/1nqrUMLyS+QBscXI1q4tTYu+EoZw0YDeIuATO345Ptl735ObhXyNJNt RoMQ== X-Gm-Message-State: APjAAAXgiZBjhXjKWJSZyRWgfDyCt6gFYXdtJl1Z1EdSN7Cjei2eFVtL vLYvreEaWAdF3s8OA+WHPP9DJCldkkE2nBjNofkbM8q7geIp X-Google-Smtp-Source: APXvYqwpyHHTx23AZtUaH6jgl3Hngv/FxRQRXeeujJMl1paZJYC6e68a5gAwAV6Dx4tz0KPVHYkW0QxYTL+D4DaFRAzSbfjuyAhZ MIME-Version: 1.0 X-Received: by 2002:a5e:cb4b:: with SMTP id h11mr66105785iok.302.1578385029481; Tue, 07 Jan 2020 00:17:09 -0800 (PST) Date: Tue, 07 Jan 2020 00:17:09 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000004d9d059b88678a@google.com> Subject: KCSAN: data-race in pid_update_inode / pid_update_inode From: syzbot To: adobriyan@gmail.com, akpm@linux-foundation.org, casey@schaufler-ca.com, christian@brauner.io, elver@google.com, keescook@chromium.org, kent.overstreet@gmail.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, mhocko@suse.com, syzkaller-bugs@googlegroups.com, tglx@linutronix.de Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 245a4300 Merge branch 'rcu/kcsan' into tip/locking/kcsan git tree: https://github.com/google/ktsan.git kcsan console output: https://syzkaller.appspot.com/x/log.txt?x=123776e1e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=a38292766f8efdaa dashboard link: https://syzkaller.appspot.com/bug?extid=41a393c8d33874c463e9 compiler: gcc (GCC) 9.0.0 20181231 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+41a393c8d33874c463e9@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in pid_update_inode / pid_update_inode read to 0xffff88812b806828 of 2 bytes by task 11180 on cpu 1: pid_update_inode+0x25/0x70 fs/proc/base.c:1818 pid_revalidate+0x91/0x120 fs/proc/base.c:1841 d_revalidate fs/namei.c:758 [inline] d_revalidate fs/namei.c:755 [inline] lookup_fast+0x612/0x6c0 fs/namei.c:1618 do_last fs/namei.c:3291 [inline] path_openat+0x2ac/0x3580 fs/namei.c:3537 do_filp_open+0x11e/0x1b0 fs/namei.c:3567 do_sys_open+0x3b3/0x4f0 fs/open.c:1097 __do_sys_open fs/open.c:1115 [inline] __se_sys_open fs/open.c:1110 [inline] __x64_sys_open+0x55/0x70 fs/open.c:1110 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 write to 0xffff88812b806828 of 2 bytes by task 11178 on cpu 0: pid_update_inode+0x51/0x70 fs/proc/base.c:1820 pid_revalidate+0x91/0x120 fs/proc/base.c:1841 d_revalidate fs/namei.c:758 [inline] d_revalidate fs/namei.c:755 [inline] lookup_fast+0x612/0x6c0 fs/namei.c:1618 do_last fs/namei.c:3291 [inline] path_openat+0x2ac/0x3580 fs/namei.c:3537 do_filp_open+0x11e/0x1b0 fs/namei.c:3567 do_sys_open+0x3b3/0x4f0 fs/open.c:1097 __do_sys_open fs/open.c:1115 [inline] __se_sys_open fs/open.c:1110 [inline] __x64_sys_open+0x55/0x70 fs/open.c:1110 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 11178 Comm: ps Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.