netlink: 12 bytes leftover after parsing attributes in pr
netlink: 12 bytes leftover after parsing attributes in process `syz.0.3218'.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.0.3218/20264 is trying to acquire lock:
ffffffff908486c0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217

but task is already holding lock:
ffff888086a18058 (&pipe->mutex){+.+.}-{4:4}, at: splice_to_socket+0x14f/0x1460 fs/splice.c:805

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #5 (&pipe->mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
       mutex_lock_nested+0x55/0x1d0 kernel/locking/rtmutex_api.c:580
       anon_pipe_prefill_and_lock fs/pipe.c:165 [inline]
       anon_pipe_write+0x292/0x1a90 fs/pipe.c:534
       __kernel_write_iter+0x453/0x8f0 fs/read_write.c:621
       __kernel_write+0x106/0x170 fs/read_write.c:641
       autofs_write fs/autofs/waitq.c:70 [inline]
       autofs_notify_daemon+0x7aa/0xf60 fs/autofs/waitq.c:177
       autofs_wait+0x11c5/0x18d0 fs/autofs/waitq.c:439
       autofs_mount_wait+0x16b/0x390 fs/autofs/root.c:256
       autofs_d_automount+0x64e/0x810 fs/autofs/root.c:410
       follow_automount fs/namei.c:1565 [inline]
       __traverse_mounts+0x2fe/0x5d0 fs/namei.c:1618
       traverse_mounts fs/namei.c:1647 [inline]
       handle_mounts fs/namei.c:1749 [inline]
       step_into_slowpath+0x4ba/0x820 fs/namei.c:2104
       step_into fs/namei.c:2152 [inline]
       walk_component fs/namei.c:2288 [inline]
       lookup_last fs/namei.c:2789 [inline]
       path_lookupat+0x433/0x8c0 fs/namei.c:2813
       filename_lookup+0x265/0x5d0 fs/namei.c:2842
       kern_path+0x3d/0x150 fs/namei.c:3036
       unix_find_bsd net/unix/af_unix.c:1219 [inline]
       unix_find_other+0x18d/0xaf0 net/unix/af_unix.c:1285
       unix_dgram_sendmsg+0x72c/0x17e0 net/unix/af_unix.c:2169
       sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800
       __sock_sendmsg net/socket.c:815 [inline]
       ____sys_sendmsg+0x565/0x870 net/socket.c:2713
       ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767
       __sys_sendmmsg+0x279/0x4e0 net/socket.c:2856
       __do_sys_sendmmsg net/socket.c:2883 [inline]
       __se_sys_sendmmsg net/socket.c:2880 [inline]
       __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2880
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #4 (&sbi->pipe_mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
       mutex_lock_nested+0x55/0x1d0 kernel/locking/rtmutex_api.c:580
       autofs_write fs/autofs/waitq.c:68 [inline]
       autofs_notify_daemon+0x797/0xf60 fs/autofs/waitq.c:177
       autofs_wait+0x11c5/0x18d0 fs/autofs/waitq.c:439
       autofs_mount_wait+0x16b/0x390 fs/autofs/root.c:256
       autofs_d_automount+0x64e/0x810 fs/autofs/root.c:410
       follow_automount fs/namei.c:1565 [inline]
       __traverse_mounts+0x2fe/0x5d0 fs/namei.c:1618
       traverse_mounts fs/namei.c:1647 [inline]
       handle_mounts fs/namei.c:1749 [inline]
       step_into_slowpath+0x4ba/0x820 fs/namei.c:2104
       step_into fs/namei.c:2152 [inline]
       walk_component fs/namei.c:2288 [inline]
       lookup_last fs/namei.c:2789 [inline]
       path_lookupat+0x433/0x8c0 fs/namei.c:2813
       filename_lookup+0x265/0x5d0 fs/namei.c:2842
       kern_path+0x3d/0x150 fs/namei.c:3036
       lookup_bdev+0xc8/0x2b0 block/bdev.c:1268
       resume_store+0x181/0x500 kernel/power/hibernate.c:1286
       kernfs_fop_write_iter+0x3a5/0x540 fs/kernfs/file.c:345
       new_sync_write fs/read_write.c:595 [inline]
       vfs_write+0x61e/0xbb0 fs/read_write.c:687
       ksys_write+0x156/0x270 fs/read_write.c:739
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #3 (&of->mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
       mutex_lock_nested+0x55/0x1d0 kernel/locking/rtmutex_api.c:580
       kernfs_seq_start+0x5d/0x420 fs/kernfs/file.c:165
       traverse+0x192/0x620 fs/seq_file.c:107
       seq_read_iter+0xb6b/0xcb0 fs/seq_file.c:196
       copy_splice_read+0x605/0xab0 fs/splice.c:362
       do_splice_read fs/splice.c:980 [inline]
       splice_direct_to_actor+0x496/0xcc0 fs/splice.c:1077
       do_splice_direct_actor fs/splice.c:1230 [inline]
       do_splice_direct+0x19b/0x2a0 fs/splice.c:1256
       vfs_copy_file_range+0xb0e/0x1370 fs/read_write.c:1633
       __do_sys_copy_file_range fs/read_write.c:1682 [inline]
       __se_sys_copy_file_range+0x2fb/0x480 fs/read_write.c:1649
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&p->lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
       mutex_lock_nested+0x55/0x1d0 kernel/locking/rtmutex_api.c:580
       seq_read_iter+0xa5/0xcb0 fs/seq_file.c:183
       __kernel_read+0x4d3/0x970 fs/read_write.c:532
       integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28
       ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:222 [inline]
       ima_calc_file_hash+0x45d/0x8a0 security/integrity/ima/ima_crypto.c:280
       ima_collect_measurement+0x521/0xa10 security/integrity/ima/ima_api.c:300
       process_measurement+0x1282/0x1c20 security/integrity/ima/ima_main.c:425
       ima_file_check+0xdc/0x130 security/integrity/ima/ima_main.c:685
       security_file_post_open+0xb3/0x260 security/security.c:2776
       do_open fs/namei.c:4847 [inline]
       path_openat+0x174d/0x2100 fs/namei.c:5010
       do_file_open+0x23e/0x4a0 fs/namei.c:5039
       do_sys_openat2+0x115/0x200 fs/open.c:1442
       do_sys_open fs/open.c:1448 [inline]
       __do_sys_openat fs/open.c:1464 [inline]
       __se_sys_openat fs/open.c:1459 [inline]
       __x64_sys_openat+0x138/0x170 fs/open.c:1459
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
       mutex_lock_nested+0x55/0x1d0 kernel/locking/rtmutex_api.c:580
       process_measurement+0x7e0/0x1c20 security/integrity/ima/ima_main.c:319
       ima_file_check+0xdc/0x130 security/integrity/ima/ima_main.c:685
       security_file_post_open+0xb3/0x260 security/security.c:2776
       do_open fs/namei.c:4847 [inline]
       path_openat+0x174d/0x2100 fs/namei.c:5010
       do_file_open+0x23e/0x4a0 fs/namei.c:5039
       file_open_name fs/open.c:1400 [inline]
       filp_open+0x16d/0x1d0 fs/open.c:1417
       kernel_read_file_from_path_initns+0xde/0x1e0 fs/kernel_read_file.c:159
       fw_get_filesystem_firmware drivers/base/firmware_loader/main.c:549 [inline]
       _request_firmware+0xa2b/0x1750 drivers/base/firmware_loader/main.c:873
       request_firmware+0x36/0x50 drivers/base/firmware_loader/main.c:948
       reg_reload_regdb+0x95/0x490 net/wireless/reg.c:1067
       genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
       genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
       genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
       netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2579
       genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
       netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
       netlink_unicast+0x90c/0xac0 net/netlink/af_netlink.c:1364
       netlink_sendmsg+0x7f0/0xb20 net/netlink/af_netlink.c:1923
       sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800
       __sock_sendmsg net/socket.c:815 [inline]
       ____sys_sendmsg+0x565/0x870 net/socket.c:2713
       ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767
       __sys_sendmsg net/socket.c:2799 [inline]
       __do_sys_sendmsg net/socket.c:2804 [inline]
       __se_sys_sendmsg net/socket.c:2802 [inline]
       __x64_sys_sendmsg+0x1b7/0x290 net/socket.c:2802
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (cb_lock){++++}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3209 [inline]
       check_prevs_add kernel/locking/lockdep.c:3328 [inline]
       validate_chain kernel/locking/lockdep.c:3952 [inline]
       __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
       lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
       down_read+0x92/0x200 kernel/locking/rwsem.c:1574
       genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
       netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
       netlink_unicast+0x90c/0xac0 net/netlink/af_netlink.c:1364
       netlink_sendmsg+0x7f0/0xb20 net/netlink/af_netlink.c:1923
       sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800
       __sock_sendmsg net/socket.c:815 [inline]
       sock_sendmsg+0x1ca/0x2d0 net/socket.c:838
       splice_to_socket+0xc50/0x1460 fs/splice.c:884
       do_splice_from fs/splice.c:936 [inline]
       do_splice+0xfb3/0x1a10 fs/splice.c:1377
       __do_splice fs/splice.c:1459 [inline]
       __do_sys_splice fs/splice.c:1662 [inline]
       __se_sys_splice+0x353/0x490 fs/splice.c:1644
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  cb_lock --> &sbi->pipe_mutex --> &pipe->mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&pipe->mutex);
                               lock(&sbi->pipe_mutex);
                               lock(&pipe->mutex);
  rlock(cb_lock);

 *** DEADLOCK ***

locks held by syz.0.3218/20264: 1, last CPU#0:
 #0: ffff888086a18058 (&pipe->mutex){+.+.}-{4:4}, at: splice_to_socket+0x14f/0x1460 fs/splice.c:805

stack backtrace:
CPU: 0 UID: 0 PID: 20264 Comm: syz.0.3218 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087
 check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219
 check_prev_add kernel/locking/lockdep.c:3209 [inline]
 check_prevs_add kernel/locking/lockdep.c:3328 [inline]
 validate_chain kernel/locking/lockdep.c:3952 [inline]
 __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
 down_read+0x92/0x200 kernel/locking/rwsem.c:1574
 genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
 netlink_unicast+0x90c/0xac0 net/netlink/af_netlink.c:1364
 netlink_sendmsg+0x7f0/0xb20 net/netlink/af_netlink.c:1923
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800
 __sock_sendmsg net/socket.c:815 [inline]
 sock_sendmsg+0x1ca/0x2d0 net/socket.c:838
 splice_to_socket+0xc50/0x1460 fs/splice.c:884
 do_splice_from fs/splice.c:936 [inline]
 do_splice+0xfb3/0x1a10 fs/splice.c:1377
 __do_splice fs/splice.c:1459 [inline]
 __do_sys_splice fs/splice.c:1662 [inline]
 __se_sys_splice+0x353/0x490 fs/splice.c:1644
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f113e16f559
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:00007f113c3be028 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00007f113e3f5fa0 RCX: 00007f113e16f559
RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f113e206b20 R08: 0000000000003000 R09: 100000000000000d
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f113e3f6038 R14: 00007f113e3f5fa0 R15: 00007ffecc787038
 </TASK>
netlink: 12 bytes leftover after parsing attributes in process `syz.0.3218'.