From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f79.google.com (mail-oo1-f79.google.com [209.85.161.79]) (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 01F3E72623 for ; Wed, 29 Jul 2026 03:36:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.79 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785296200; cv=none; b=qcf+5zYIOSv4mA5AOdu2epd0XVFhVfhBMoMtoTbgfLOXp0nO7L7AyRy1nhHhiF/5mihvjkZSeII7HltTc6jKaW9nFzDe/P9rBJ/v/Zxr4PatqLcYN+l0Gh5TFgSJdJNO3T7l0ar5p3pNA3vhEaTkfcCCryktY8hc7Ee6W/TTbZU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785296200; c=relaxed/simple; bh=Fq5KXqB0ouEigAxyyoVDAqk1ybZBJ6LJQSwIjdYv8jY=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=VIgPd/1//pK5V2ixtNcJEC64aXr8/hhe+n8w0TvBk15jJm8oKF5oO8cSbZ1mgLJTqusgmkzkxp5Msh1npqkebbM3Fvmj9kq808M+ga8zkdsfMvauF9tti1mfu1zMt31ca64D0jRNPiAxDEsP6ZX1n7WJgLbcx1GxiTSGJENp1r0= 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=209.85.161.79 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-oo1-f79.google.com with SMTP id 006d021491bc7-6aaefd6909fso287510eaf.2 for ; Tue, 28 Jul 2026 20:36:38 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785296198; x=1785900998; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=zoRbr/2h7I9PSmbEC0Pnvz218hVaoI8f/dcTXSgXG+w=; b=kAmA/5rQK1DvTdz5z0Gp3iMctoXLafx1/WJpV0yzO7JQSvvMDQVpzZkyay2y3FocR9 2r5WNuIN8LQZzynIfTc6VP8F0lUj96OFcD2XPtPWUTl+CLxZiwbntt8DDfz/UWWO98AZ Xf6lyAEt3v9tH+MKUdx+d/AAFJZLevFTj1sWkjmb/uoqFkGQuyJIQNLoWl5dTpkDd9qO FBdf2OVJzXotgsFviUeHaviMyK6qVfVoDZapNRCw69gp8ULX66gu4kQEg5+ftIbaw4Dd G0VQgYBnNvDBKT4MCUSK/uVoi0na4byxtoEQ45K6fgvE7n9TU8GyoVV7eLbQGFmLxGDf /ivQ== X-Forwarded-Encrypted: i=1; AHgh+Rq1Pv+VBZA9l1dRuuQBt9zpSbF30NBEJTZk+9AxcdpURihBWZvFrcMZReQ5k1g6yIh6Oq+hvhF39elE3xkV@vger.kernel.org X-Gm-Message-State: AOJu0YwOFiULxgDTZsuiLANJho7TYBljvAC8PZ4qn8CxHRfNfBCw6xVL iucqIisQAoTQWpJKjYjAtWfXW1WtQoPIymE39wUl1qKK0mRHBVmT2gJ9TR6wqj8Ey8LyP9F988G 04SFPajEAOM+dJDNzBah/JU7nST8beGgF+SzxP65qb3yVfk2njOhxMVtm+SY= Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:4d09:b0:6aa:c76b:6c30 with SMTP id 006d021491bc7-6ac96cf80fdmr2230773eaf.39.1785296197943; Tue, 28 Jul 2026 20:36:37 -0700 (PDT) Date: Tue, 28 Jul 2026 20:36:37 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a697545.6bd615f2.c0aa.0008.GAE@google.com> Subject: [syzbot] [fs?] possible deadlock in path_openat (5) From: syzbot To: a.hindborg@kernel.org, leitao@debian.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 0ce37745d4bf Merge tag 'block-7.2-20260724' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10d866b9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782 dashboard link: https://syzkaller.appspot.com/bug?extid=4c9318af45f0bf2af153 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/19521188f055/disk-0ce37745.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/2f7922f1fe08/vmlinux-0ce37745.xz kernel image: https://storage.googleapis.com/syzbot-assets/1a7a0ce66cfa/bzImage-0ce37745.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+4c9318af45f0bf2af153@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.5.3348/18446 is trying to acquire lock: ffff88803564a450 (sb_writers#6){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:4597 [inline] ffff88803564a450 (sb_writers#6){.+.+}-{0:0}, at: path_openat+0xad9/0x4280 fs/namei.c:4860 but task is already holding lock: ffff888076068920 (&common->filesem){+.+.}-{4:4}, at: fsg_store_file+0x193/0x450 drivers/usb/gadget/function/storage_common.c:452 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&common->filesem){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 down_write+0x8b/0x1f0 kernel/locking/rwsem.c:1631 fsg_store_file+0x193/0x450 drivers/usb/gadget/function/storage_common.c:452 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #5 (&p->frag_sem){++++}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 down_read+0x99/0x4c0 kernel/locking/rwsem.c:1574 fill_read_buffer fs/configfs/file.c:66 [inline] configfs_read_iter+0x346/0x6f0 fs/configfs/file.c:88 __kernel_read+0x397/0xad0 fs/read_write.c:532 integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28 ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222 ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280 ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300 process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425 ima_file_check+0xc3/0x110 security/integrity/ima/ima_main.c:685 security_file_post_open+0xc4/0x210 security/security.c:2755 do_open fs/namei.c:4702 [inline] path_openat+0x985/0x4280 fs/namei.c:4863 do_file_open+0x20e/0x430 fs/namei.c:4892 do_sys_openat2+0x10f/0x1e0 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&buffer->mutex){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x1a4/0x1bd0 kernel/locking/mutex.c:821 configfs_read_iter+0x79/0x6f0 fs/configfs/file.c:86 __kernel_read+0x397/0xad0 fs/read_write.c:532 integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28 ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222 ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280 ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300 process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425 ima_file_check+0xc3/0x110 security/integrity/ima/ima_main.c:685 security_file_post_open+0xc4/0x210 security/security.c:2755 do_open fs/namei.c:4702 [inline] path_openat+0x985/0x4280 fs/namei.c:4863 do_file_open+0x20e/0x430 fs/namei.c:4892 do_sys_openat2+0x10f/0x1e0 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x1a4/0x1bd0 kernel/locking/mutex.c:821 process_measurement+0x5ab/0x2350 security/integrity/ima/ima_main.c:319 ima_file_check+0xc3/0x110 security/integrity/ima/ima_main.c:685 security_file_post_open+0xc4/0x210 security/security.c:2755 do_open fs/namei.c:4702 [inline] path_openat+0x985/0x4280 fs/namei.c:4863 do_file_open_root+0x2f6/0x5a0 fs/namei.c:4916 file_open_root+0x1c6/0x3f0 fs/open.c:1355 kernel_read_file_from_path_initns+0x189/0x260 fs/kernel_read_file.c:163 fw_get_filesystem_firmware drivers/base/firmware_loader/main.c:549 [inline] _request_firmware+0x733/0x13c0 drivers/base/firmware_loader/main.c:873 request_firmware+0x35/0x50 drivers/base/firmware_loader/main.c:948 reg_reload_regdb+0x85/0x460 net/wireless/reg.c:1067 genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0xa4d/0xbe0 net/socket.c:2684 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2738 __sys_sendmsg+0x160/0x210 net/socket.c:2770 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (cb_lock){++++}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 down_read+0x99/0x4c0 kernel/locking/rwsem.c:1574 genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] sock_sendmsg+0x394/0x410 net/socket.c:813 splice_to_socket+0xb3c/0x11a0 fs/splice.c:884 do_splice_from fs/splice.c:936 [inline] do_splice+0x109c/0x1f90 fs/splice.c:1349 __do_splice+0x33b/0x370 fs/splice.c:1431 __do_sys_splice fs/splice.c:1634 [inline] __se_sys_splice fs/splice.c:1616 [inline] __x64_sys_splice+0x187/0x250 fs/splice.c:1616 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&pipe->mutex){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x1a4/0x1bd0 kernel/locking/mutex.c:821 pipe_lock fs/pipe.c:91 [inline] pipe_lock+0x69/0x80 fs/pipe.c:88 iter_file_splice_write+0x1fd/0x10b0 fs/splice.c:682 do_splice_from fs/splice.c:936 [inline] do_splice+0x109c/0x1f90 fs/splice.c:1349 __do_splice+0x33b/0x370 fs/splice.c:1431 __do_sys_splice fs/splice.c:1634 [inline] __se_sys_splice fs/splice.c:1616 [inline] __x64_sys_splice+0x187/0x250 fs/splice.c:1616 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sb_writers#6){.+.+}-{0:0}: check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3165 check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x136c/0x1a40 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_write include/linux/fs/super.h:125 [inline] mnt_want_write+0x6f/0x410 fs/namespace.c:494 open_last_lookups fs/namei.c:4597 [inline] path_openat+0xad9/0x4280 fs/namei.c:4860 do_file_open+0x20e/0x430 fs/namei.c:4892 file_open_name+0x1c3/0x3e0 fs/open.c:1326 filp_open+0x2e/0x50 fs/open.c:1343 fsg_lun_open+0x6b/0x7b0 drivers/usb/gadget/function/storage_common.c:194 fsg_store_file+0x1e7/0x450 drivers/usb/gadget/function/storage_common.c:455 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: sb_writers#6 --> &p->frag_sem --> &common->filesem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&common->filesem); lock(&p->frag_sem); lock(&common->filesem); rlock(sb_writers#6); *** DEADLOCK *** 5 locks held by syz.5.3348/18446: #0: ffff88807a6470b0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259 #1: ffff88801e730450 (sb_writers#14){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739 #2: ffff888068736480 (&buffer->mutex){+.+.}-{4:4}, at: configfs_write_iter+0x76/0x4e0 fs/configfs/file.c:226 #3: ffff888058e5c970 (&p->frag_sem){++++}-{4:4}, at: flush_write_buffer fs/configfs/file.c:205 [inline] #3: ffff888058e5c970 (&p->frag_sem){++++}-{4:4}, at: configfs_write_iter+0x218/0x4e0 fs/configfs/file.c:229 #4: ffff888076068920 (&common->filesem){+.+.}-{4:4}, at: fsg_store_file+0x193/0x450 drivers/usb/gadget/function/storage_common.c:452 stack backtrace: CPU: 0 UID: 0 PID: 18446 Comm: syz.5.3348 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2175 check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3165 check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x136c/0x1a40 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_write include/linux/fs/super.h:125 [inline] mnt_want_write+0x6f/0x410 fs/namespace.c:494 open_last_lookups fs/namei.c:4597 [inline] path_openat+0xad9/0x4280 fs/namei.c:4860 do_file_open+0x20e/0x430 fs/namei.c:4892 file_open_name+0x1c3/0x3e0 fs/open.c:1326 filp_open+0x2e/0x50 fs/open.c:1343 fsg_lun_open+0x6b/0x7b0 drivers/usb/gadget/function/storage_common.c:194 fsg_store_file+0x1e7/0x450 drivers/usb/gadget/function/storage_common.c:455 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f072db9de99 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f072eb12028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f072de25fa0 RCX: 00007f072db9de99 RDX: 0000000000000001 RSI: 0000200000000f00 RDI: 0000000000000003 RBP: 00007f072dc33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f072de26038 R14: 00007f072de25fa0 R15: 00007fff6d0c4d58 mass_storage.usb0/lun.0: unable to open backing file: f --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup