From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f208.google.com (mail-oi1-f208.google.com [209.85.167.208]) (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 84DA42F3C18 for ; Wed, 29 Jul 2026 05:27:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.208 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785302852; cv=none; b=YcuhgJOHZlWdziM8xvHhxODlDAnrUfjGEf/O1+HP323iXIbBVqXYhCeJ37x08jp0bF7X5iBsAJS275GZUZxhqNDF5gtzNIKlT2wR6mfJGfTVFxX2VN+qd2mVCggCxs3RqqLd5UJOTcvnSFOiqj8pJoWY9SKVT62DoVTX6YmJFdg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785302852; c=relaxed/simple; bh=i9jEe0P2sE9IW8SXt73vwdCcYhMgdpeG6EXSa7wQ14g=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=d3weVkLeX7olIzWtUhsBw0BDl0S2rh3OmtRZ2MyL0IeOmcMFvKbocNIrte0hzV4zF0Qy6dg4rzvOBWnJW4Lm+C966B+hcDlKjC6vg0TqEL94JNMFRFl/GA7iAqMlkWbxjNcfNHWE7ffvRsLP65e/eAFJ7Pwv9YpWrOwfHM3iO6s= 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=209.85.167.208 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-oi1-f208.google.com with SMTP id 5614622812f47-4a416619e8dso724644b6e.1 for ; Tue, 28 Jul 2026 22:27:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785302849; x=1785907649; 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=rIn/LBI9JBxDR42/aRTpRVXPaJbvrdIj7QtaG6wYi/E=; b=Wsm9YeFK0w2WtnksonNy7BB0fp/6u5svxT5TVlmHZrC+/8VLOEuvRj/CwV2+vz8I6A GlD2ZWFfy8BjnjSK/kXlg/DrIm3WwNv365SOwGComOq+bPQGPL45lv0KspGHLFbrS2IR oclvOO3Iu4f0/uijmwrNHM06SLs71dWGrcn8xuzwCtv3Ry8YyossCElf+26zBWDZKg8v nz8k4NIzu59aDXgZ7K5mH7im3wT5tRrVSMyfKTE22R9xOp7yCHkjlAgltMRuxftpR4QP JxgHM3Tb08eIjvuKb3xyppjHq9BcpZPHmJoc115ASW09jwTtQJIqoLqlcqOSYuM4+ZVN BxZQ== X-Forwarded-Encrypted: i=1; AHgh+Rp17IPXQ+rqcI0mBhh+oDdVGwvwYg7+aUTkolXQEI18B606LUxPlNQt+GFvhJMaAchTuaWHkhZyx41gwy0=@vger.kernel.org X-Gm-Message-State: AOJu0YzNqGJnKIx53+A6NYR5K2WPGdLcQYV4laZjP2nVJv8sY8dhKzJB Pkw6sPHDIZEZTGxNi4B/fiTmHgYEfGmCQ7hFcCJop3wXkl/PqM2O6upaNR5PAAAbY7snMSkq2ZI p6J99VXgYmfyJx4yKCYD6M4xApRx832wya534pDvzV6buzB9aICf4Qrp0zLc= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:1646:b0:49a:7714:ed25 with SMTP id 5614622812f47-4ad730d1443mr438633b6e.3.1785302849472; Tue, 28 Jul 2026 22:27:29 -0700 (PDT) Date: Tue, 28 Jul 2026 22:27:29 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a698f41.d9e86bb5.297b12.0052.GAE@google.com> Subject: [syzbot] [fs?] possible deadlock in configfs_read_iter 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: f5098b6bae76 Linux 7.2-rc5 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=137026b9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782 dashboard link: https://syzkaller.appspot.com/bug?extid=d2085ac2d653b9e383e2 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/2113dcf433f6/disk-f5098b6b.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/413e673b7de4/vmlinux-f5098b6b.xz kernel image: https://storage.googleapis.com/syzbot-assets/fc40c1b83e80/bzImage-f5098b6b.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d2085ac2d653b9e383e2@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.3.4908/17817 is trying to acquire lock: ffff88807ab9cc80 (&buffer->mutex){+.+.}-{4:4}, at: configfs_read_iter+0x79/0x6f0 fs/configfs/file.c:86 but task is already holding lock: ffff8880741349a8 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x5ab/0x2350 security/integrity/ima/ima_main.c:319 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&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 -> #5 (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 -> #4 (&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 -> #3 (sb_writers#6){.+.+}-{0:0}: 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 -> #2 (&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 -> #1 (&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 flush_write_buffer fs/configfs/file.c:205 [inline] configfs_write_iter+0x218/0x4e0 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 -> #0 (&buffer->mutex){+.+.}-{4:4}: 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 __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 other info that might help us debug this: Chain exists of: &buffer->mutex --> cb_lock --> &ima_iint_mutex_key[depth] Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ima_iint_mutex_key[depth]); lock(cb_lock); lock(&ima_iint_mutex_key[depth]); lock(&buffer->mutex); *** DEADLOCK *** 1 lock held by syz.3.4908/17817: #0: ffff8880741349a8 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x5ab/0x2350 security/integrity/ima/ima_main.c:319 stack backtrace: CPU: 0 UID: 0 PID: 17817 Comm: syz.3.4908 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 __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 RIP: 0033:0x7f3adaf9de99 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:00007f3adbf33028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f3adb225fa0 RCX: 00007f3adaf9de99 RDX: 0000000000000000 RSI: 0000200000000640 RDI: ffffffffffffff9c RBP: 00007f3adb033eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3adb226038 R14: 00007f3adb225fa0 R15: 00007ffd05bb3858 syz_tun (unregistering): left allmulticast mode --- 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