From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f208.google.com (mail-il1-f208.google.com [209.85.166.208]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A51821FECBC for ; Wed, 5 Feb 2025 22:22:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.208 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738794144; cv=none; b=YccMcUoIAGyE471gQHq193qZHpjLNbi5qF/Eoqm81Rwtx42JvcJeqAoV0bE5hd4dKvxvxzoQw1d75EgBVoRc9Ilg9Z+mEE5B08F/aHcR21ITKvwFCz2qQPrYKqYQ67JwKERfbn5It3uF8JAAR+NXhoRJ4aqYTm2IcCnqKYhXK8g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738794144; c=relaxed/simple; bh=bJFLp0XeWoy0Wbj14E0G32xDLGx8rBdaR0tauL5LNmU=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=pVlokepGoT+kD4KQNn91BFHqimGlOf63jxbgIItj6w/iSI/HLSo5pMhsndqja491H8H9p4/iFTBH7noGExuRJ85fT2HnHAE6mMpVx2P5zO1LUUVjt+EgUAkna7ok4JjqfuJTU5zkDL0X1hOfhC1RFczHTVT+cNRBZJ7xxmvmS5c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.208 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-il1-f208.google.com with SMTP id e9e14a558f8ab-3ce3bbb2b9dso1722225ab.3 for ; Wed, 05 Feb 2025 14:22:22 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738794142; x=1739398942; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=avAw4ndW1Mba+XlAfaMHMADvM10uoCqU4hpvq784fbw=; b=E+MAvyLRCrzale/4Ps0/T56tf54uf8+ApcSN/IRZ8GR/UhSwN7DueFju9iSOhBkkPA 6i540lQfETWGZkQjfV1jh5J/d5r1FeIvf0tvuHpftzH/CMlobIyPwb+Ff9b2++4u+cjV NugfZM5njuH61knugKeFtQpsORmTkFnCKsVd4u+rgDDQfieOfQPDF2vyXU7oVEFg8csC 2CkxSS0BQk+dK0ofVmXs9041Wll9VeV4g1T+6rMldP45BywKWWj9bBV8SqmskYUO0+Dx 4URV/Z6gT1Keecr4inEDGwK7tH5q7+IBlVAG/1WkBLskkhYwgHBpw6SIjLXIoVZmyhe7 iezw== X-Forwarded-Encrypted: i=1; AJvYcCWz9UNxcq+JJjREK96hh3xHe82BctjVAzInXG2ukhxKnY2a1RenAFYPi5T6a16+cazkTuFknBvtTeC6/o0=@vger.kernel.org X-Gm-Message-State: AOJu0Yxil086DUEk4mZXbQq0bFOJwY+pZpg6KIZnXt9MIZ7ca1DkRZII llpPPIaVZHG0mFQyK3cCiY1NRk4hhN0TVmJEkRE0vsFolAmsPYutKDe1OL05XZSEs3ZFH1YQkJT k1/1phstwrtJTEwFrWih/CEYGJFW6mYedpEsz6Nn44BxU6bC8LllBoIs= X-Google-Smtp-Source: AGHT+IGwUqYYLWvK4yfvYFIaFjyq97vE5KTxe7rnR/C7y8lPlKntf43pmuN1Gyx2ysJNWfrr8m+Am/QZgN58vRBT3P6GaLEgjl1i Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:3309:b0:3cf:fc11:90ca with SMTP id e9e14a558f8ab-3d04f42561emr45209305ab.6.1738794141784; Wed, 05 Feb 2025 14:22:21 -0800 (PST) Date: Wed, 05 Feb 2025 14:22:21 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <67a3e49d.050a0220.19061f.05f0.GAE@google.com> Subject: [syzbot] [autofs?] possible deadlock in pipe_write (2) From: syzbot To: autofs@vger.kernel.org, linux-kernel@vger.kernel.org, raven@themaw.net, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 69e858e0b8b2 Merge tag 'uml-for-linus-6.14-rc1' of git://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15d2fddf980000 kernel config: https://syzkaller.appspot.com/x/.config?x=57ab43c279fa614d dashboard link: https://syzkaller.appspot.com/bug?extid=25dd3743576b83be4773 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/7b9951b25c33/disk-69e858e0.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/3814bbc0e86f/vmlinux-69e858e0.xz kernel image: https://storage.googleapis.com/syzbot-assets/da44e7be7454/bzImage-69e858e0.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+25dd3743576b83be4773@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.13.0-syzkaller-09760-g69e858e0b8b2 #0 Not tainted ------------------------------------------------------ syz.1.2997/15256 is trying to acquire lock: ffff888011f30468 (&pipe->mutex){+.+.}-{4:4}, at: pipe_write+0x1c6/0x1a30 fs/pipe.c:456 but task is already holding lock: ffff888022e95140 (&sbi->pipe_mutex){+.+.}-{4:4}, at: autofs_write fs/autofs/waitq.c:55 [inline] ffff888022e95140 (&sbi->pipe_mutex){+.+.}-{4:4}, at: autofs_notify_daemon+0x71a/0xf70 fs/autofs/waitq.c:164 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sbi->pipe_mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730 autofs_write fs/autofs/waitq.c:55 [inline] autofs_notify_daemon+0x71a/0xf70 fs/autofs/waitq.c:164 autofs_wait+0x10b8/0x1b30 fs/autofs/waitq.c:426 autofs_mount_wait+0x170/0x330 fs/autofs/root.c:255 autofs_d_automount+0x555/0x710 fs/autofs/root.c:401 follow_automount fs/namei.c:1454 [inline] __traverse_mounts+0x2ba/0x580 fs/namei.c:1499 traverse_mounts fs/namei.c:1528 [inline] handle_mounts fs/namei.c:1631 [inline] step_into+0x5e5/0x10b0 fs/namei.c:1952 lookup_last fs/namei.c:2612 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2636 filename_lookup+0x2a3/0x670 fs/namei.c:2665 kern_path+0x35/0x50 fs/namei.c:2773 lookup_bdev+0xc5/0x290 block/bdev.c:1163 resume_store+0x1a0/0x710 kernel/power/hibernate.c:1247 kernfs_fop_write_iter+0x3a0/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xacf/0xd10 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&of->mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730 kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] do_splice+0xd68/0x18b0 fs/splice.c:1354 __do_splice fs/splice.c:1436 [inline] __do_sys_splice fs/splice.c:1639 [inline] __se_sys_splice+0x2e0/0x450 fs/splice.c:1621 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&pipe->mutex){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730 pipe_write+0x1c6/0x1a30 fs/pipe.c:456 __kernel_write_iter+0x4b3/0x950 fs/read_write.c:612 __kernel_write+0x120/0x180 fs/read_write.c:632 autofs_write fs/autofs/waitq.c:57 [inline] autofs_notify_daemon+0x72d/0xf70 fs/autofs/waitq.c:164 autofs_wait+0x10b8/0x1b30 fs/autofs/waitq.c:426 autofs_mount_wait+0x170/0x330 fs/autofs/root.c:255 autofs_d_automount+0x555/0x710 fs/autofs/root.c:401 follow_automount fs/namei.c:1454 [inline] __traverse_mounts+0x2ba/0x580 fs/namei.c:1499 traverse_mounts fs/namei.c:1528 [inline] handle_mounts fs/namei.c:1631 [inline] step_into+0x5e5/0x10b0 fs/namei.c:1952 lookup_last fs/namei.c:2612 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2636 filename_lookup+0x2a3/0x670 fs/namei.c:2665 kern_path+0x35/0x50 fs/namei.c:2773 lookup_bdev+0xc5/0x290 block/bdev.c:1163 resume_store+0x1a0/0x710 kernel/power/hibernate.c:1247 kernfs_fop_write_iter+0x3a0/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xacf/0xd10 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &pipe->mutex --> &of->mutex --> &sbi->pipe_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sbi->pipe_mutex); lock(&of->mutex); lock(&sbi->pipe_mutex); lock(&pipe->mutex); *** DEADLOCK *** 5 locks held by syz.1.2997/15256: #0: ffff888030adcd38 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x254/0x320 fs/file.c:1192 #1: ffff8880359fa420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3023 [inline] #1: ffff8880359fa420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd10 fs/read_write.c:675 #2: ffff88804665a888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #3: ffff8881412ffa58 (kn->active#59){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #4: ffff888022e95140 (&sbi->pipe_mutex){+.+.}-{4:4}, at: autofs_write fs/autofs/waitq.c:55 [inline] #4: ffff888022e95140 (&sbi->pipe_mutex){+.+.}-{4:4}, at: autofs_notify_daemon+0x71a/0xf70 fs/autofs/waitq.c:164 stack backtrace: CPU: 1 UID: 0 PID: 15256 Comm: syz.1.2997 Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2076 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730 pipe_write+0x1c6/0x1a30 fs/pipe.c:456 __kernel_write_iter+0x4b3/0x950 fs/read_write.c:612 __kernel_write+0x120/0x180 fs/read_write.c:632 autofs_write fs/autofs/waitq.c:57 [inline] autofs_notify_daemon+0x72d/0xf70 fs/autofs/waitq.c:164 autofs_wait+0x10b8/0x1b30 fs/autofs/waitq.c:426 autofs_mount_wait+0x170/0x330 fs/autofs/root.c:255 autofs_d_automount+0x555/0x710 fs/autofs/root.c:401 follow_automount fs/namei.c:1454 [inline] __traverse_mounts+0x2ba/0x580 fs/namei.c:1499 traverse_mounts fs/namei.c:1528 [inline] handle_mounts fs/namei.c:1631 [inline] step_into+0x5e5/0x10b0 fs/namei.c:1952 lookup_last fs/namei.c:2612 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2636 filename_lookup+0x2a3/0x670 fs/namei.c:2665 kern_path+0x35/0x50 fs/namei.c:2773 lookup_bdev+0xc5/0x290 block/bdev.c:1163 resume_store+0x1a0/0x710 kernel/power/hibernate.c:1247 kernfs_fop_write_iter+0x3a0/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xacf/0xd10 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f504898cda9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f50498d2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f5048ba5fa0 RCX: 00007f504898cda9 RDX: 0000000000000012 RSI: 0000000020000000 RDI: 0000000000000008 RBP: 00007f5048a0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5048ba5fa0 R15: 00007ffe28e15a78 PM: Image not found (code -6) --- This report is generated by a bot. 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