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=-8.7 required=3.0 tests=BAYES_00,FROM_LOCAL_DIGITS, FROM_LOCAL_HEX,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS 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 9AC39C433B4 for ; Sun, 4 Apr 2021 04:15:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5538A6137E for ; Sun, 4 Apr 2021 04:15:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229789AbhDDEPX (ORCPT ); Sun, 4 Apr 2021 00:15:23 -0400 Received: from mail-io1-f69.google.com ([209.85.166.69]:44373 "EHLO mail-io1-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229754AbhDDEPX (ORCPT ); Sun, 4 Apr 2021 00:15:23 -0400 Received: by mail-io1-f69.google.com with SMTP id e11so8805093ioh.11 for ; Sat, 03 Apr 2021 21:15:18 -0700 (PDT) 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=XwVdYv6tSytCkwcKFS5bJFOKjHMNQE78mO+cN9dKetk=; b=Ny9cJU4qKPDC1wVX+vj1FdVTKOnLZAJyaCa8qLBWEMJenOP937PlHm1gSojtxFzzsQ 1yGHB2RmLt8RWJmxGwx/zxo0HKiukFZRpT+SF8mcOz63NroprNa6tuMvwtTVIc+BzvcI NtRd0+Nh7MZ+DrZzIjCJLKOEfXQCD14ejv/kgbI3Zh4H+qraHnUJRYupEFgr0aqkbue1 /5fUTefsAneaY7Z8eZlNZ5sFd7Q1+cswDsRbTaNM0kf+mynTlNMjPbpTZLdTgyohHsDC ZOu4ZxcuHfTVViPzADLrOxMXsJoI8oZIEvda5myWlGV0sAkBUV8r/N0bIxLA/aasXc2s sq2w== X-Gm-Message-State: AOAM533FtM4T4mlqxSw6yZu/sUhcwC3GOWbJIQ1AnB6WfQkrwnPDSNA+ AwR9S6IMoM/BTD6pkIQmawLpKpq+iVioiblIdmf1biUm6iZ3 X-Google-Smtp-Source: ABdhPJwZ5MI4HfRYIWlxcFFiKKZ8XNsKwjvwjNOfdJbs9wONLYMscwaLif5HPLDBuoHFWo8Wij6/bUkvBGLK6ccaUihclvJA5NAM MIME-Version: 1.0 X-Received: by 2002:a5e:990f:: with SMTP id t15mr15230556ioj.180.1617509717745; Sat, 03 Apr 2021 21:15:17 -0700 (PDT) Date: Sat, 03 Apr 2021 21:15:17 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000025a67605bf1dd4ab@google.com> Subject: [syzbot] WARNING: suspicious RCU usage in getname_flags From: syzbot To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: 2bb25b3a Merge tag 'mips-fixes_5.12_3' of git://git.kernel.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1284cc31d00000 kernel config: https://syzkaller.appspot.com/x/.config?x=78ef1d159159890 dashboard link: https://syzkaller.appspot.com/bug?extid=dde0cc33951735441301 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+dde0cc33951735441301@syzkaller.appspotmail.com WARNING: suspicious RCU usage 5.12.0-rc5-syzkaller #0 Not tainted ----------------------------- kernel/sched/core.c:8294 Illegal context switch in RCU-bh read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 0 no locks held by systemd-udevd/4825. stack backtrace: CPU: 0 PID: 4825 Comm: systemd-udevd Not tainted 5.12.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 ___might_sleep+0x229/0x2c0 kernel/sched/core.c:8294 __might_fault+0x6e/0x180 mm/memory.c:5018 strncpy_from_user+0x2f/0x3e0 lib/strncpy_from_user.c:117 getname_flags.part.0+0x95/0x4f0 fs/namei.c:149 getname_flags fs/namei.c:2733 [inline] user_path_at_empty+0xa1/0x100 fs/namei.c:2733 user_path_at include/linux/namei.h:60 [inline] do_faccessat+0x127/0x850 fs/open.c:425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f840445f9c7 Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffdc40178d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 0000564d558c9760 RCX: 00007f840445f9c7 RDX: 00746e657665752f RSI: 0000000000000000 RDI: 00007ffdc40178e0 RBP: 00007ffdc4017960 R08: 0000000000004400 R09: 0000000000001010 R10: 0000000000000020 R11: 0000000000000246 R12: 0000564d557b1856 R13: 0000564d558ed190 R14: 00007ffdc40178e0 R15: 0000564d558fe590 --- This report 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 issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.