nfs4: Unknown parameter 'øÿÿÿ' ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.8.4412/25103 is trying to acquire lock: ffff88803ef4f2c0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xa5/0xcb0 fs/seq_file.c:183 but task is already holding lock: ffff888073fc8058 (&pipe->mutex){+.+.}-{4:4}, at: splice_file_to_pipe+0x3e/0x6c0 fs/splice.c:1270 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&pipe->mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 anon_pipe_write+0x290/0x1c30 fs/pipe.c:553 __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:57 [inline] autofs_notify_daemon+0x777/0xed0 fs/autofs/waitq.c:164 autofs_wait+0x11d8/0x18b0 fs/autofs/waitq.c:426 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 __do_sys_chdir fs/open.c:557 [inline] __se_sys_chdir+0xa8/0x2a0 fs/open.c:550 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #5 (&sbi->pipe_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 autofs_write fs/autofs/waitq.c:55 [inline] autofs_notify_daemon+0x764/0xed0 fs/autofs/waitq.c:164 autofs_wait+0x11d8/0x18b0 fs/autofs/waitq.c:426 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 bpf_prog_get_type_path+0xa3/0x270 kernel/bpf/inode.c:642 __bpf_mt_check_path net/netfilter/xt_bpf.c:60 [inline] bpf_mt_check_v1+0x156/0x360 net/netfilter/xt_bpf.c:84 xt_checkentry_match net/netfilter/x_tables.c:543 [inline] xt_check_match+0x602/0xce0 net/netfilter/x_tables.c:576 __nft_match_init+0x66b/0x8c0 net/netfilter/nft_compat.c:530 nft_match_large_init+0xc0/0x150 net/netfilter/nft_compat.c:552 nf_tables_newexpr net/netfilter/nf_tables_api.c:3633 [inline] nf_tables_newrule+0x179e/0x28a0 net/netfilter/nf_tables_api.c:4451 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:524 [inline] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:647 [inline] nfnetlink_rcv+0x1291/0x28d0 net/netfilter/nfnetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:785 __sock_sendmsg net/socket.c:800 [inline] ____sys_sendmsg+0x565/0x870 net/socket.c:2702 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2756 __sys_sendmsg net/socket.c:2788 [inline] __do_sys_sendmsg net/socket.c:2793 [inline] __se_sys_sendmsg net/socket.c:2791 [inline] __x64_sys_sendmsg+0x1b7/0x290 net/socket.c:2791 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&nft_net->commit_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 nf_tables_netdev_event+0xad/0x160 net/netfilter/nft_chain_filter.c:416 call_netdevice_notifier net/core/dev.c:1892 [inline] call_netdevice_register_notifiers net/core/dev.c:1900 [inline] call_netdevice_register_net_notifiers+0x12a/0x560 net/core/dev.c:1931 register_netdevice_notifier+0x10b/0x440 net/core/dev.c:1987 nft_chain_filter_netdev_init net/netfilter/nft_chain_filter.c:442 [inline] nft_chain_filter_init+0x1d/0x80 net/netfilter/nft_chain_filter.c:468 nf_tables_module_init+0x25/0x100 net/netfilter/nf_tables_api.c:12213 do_one_initcall+0x250/0x870 init/main.c:1347 do_initcall_level+0x10a/0x1a0 init/main.c:1409 do_initcalls+0x59/0xa0 init/main.c:1425 kernel_init_freeable+0x29d/0x3e0 init/main.c:1658 kernel_init+0x1d/0x1d0 init/main.c:1548 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #3 (&dev_instance_lock_key#3){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 netdev_lock include/linux/netdevice.h:2842 [inline] netdev_lock_ops include/net/netdev_lock.h:42 [inline] do_setlink+0x8de/0x4670 net/core/rtnetlink.c:3163 rtnl_changelink net/core/rtnetlink.c:3849 [inline] __rtnl_newlink net/core/rtnetlink.c:4022 [inline] rtnl_newlink+0x15c2/0x1bd0 net/core/rtnetlink.c:4159 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:785 __sock_sendmsg net/socket.c:800 [inline] __sys_sendto+0x41e/0x5d0 net/socket.c:2267 __do_sys_sendto net/socket.c:2274 [inline] __se_sys_sendto net/socket.c:2270 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2270 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (dev_addr_sem){++++}-{4:4}: down_read+0x97/0x200 kernel/locking/rwsem.c:1574 address_show+0x25/0x250 net/core/net-sysfs.c:260 dev_attr_show+0x58/0xc0 drivers/base/core.c:2487 sysfs_kf_seq_show+0x331/0x490 fs/sysfs/file.c:65 seq_read_iter+0x464/0xcb0 fs/seq_file.c:231 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x59e/0xa90 fs/read_write.c:574 ksys_read+0x156/0x270 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&of->mutex#2){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 kernfs_seq_start+0x5d/0x420 fs/kernfs/file.c:165 seq_read_iter+0x37f/0xcb0 fs/seq_file.c:226 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x59e/0xa90 fs/read_write.c:574 ksys_read+0x156/0x270 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&p->lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3167 [inline] check_prevs_add kernel/locking/lockdep.c:3286 [inline] validate_chain kernel/locking/lockdep.c:3910 [inline] __lock_acquire+0x1520/0x2ce0 kernel/locking/lockdep.c:5239 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5870 __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 seq_read_iter+0xa5/0xcb0 fs/seq_file.c:183 copy_splice_read+0x605/0xab0 fs/splice.c:346 do_splice_read fs/splice.c:963 [inline] splice_file_to_pipe+0x450/0x6c0 fs/splice.c:1273 do_sendfile+0x4e6/0x7e0 fs/read_write.c:1400 __do_sys_sendfile64 fs/read_write.c:1455 [inline] __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1441 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 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: &p->lock --> &sbi->pipe_mutex --> &pipe->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pipe->mutex); lock(&sbi->pipe_mutex); lock(&pipe->mutex); lock(&p->lock); *** DEADLOCK *** 1 lock held by syz.8.4412/25103: #0: ffff888073fc8058 (&pipe->mutex){+.+.}-{4:4}, at: splice_file_to_pipe+0x3e/0x6c0 fs/splice.c:1270 stack backtrace: CPU: 1 UID: 0 PID: 25103 Comm: syz.8.4412 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2045 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3167 [inline] check_prevs_add kernel/locking/lockdep.c:3286 [inline] validate_chain kernel/locking/lockdep.c:3910 [inline] __lock_acquire+0x1520/0x2ce0 kernel/locking/lockdep.c:5239 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5870 __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 seq_read_iter+0xa5/0xcb0 fs/seq_file.c:183 copy_splice_read+0x605/0xab0 fs/splice.c:346 do_splice_read fs/splice.c:963 [inline] splice_file_to_pipe+0x450/0x6c0 fs/splice.c:1273 do_sendfile+0x4e6/0x7e0 fs/read_write.c:1400 __do_sys_sendfile64 fs/read_write.c:1455 [inline] __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1441 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efda944ce59 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:00007efda767d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007efda96c6090 RCX: 00007efda944ce59 RDX: 0000000000000000 RSI: 000000000000000a RDI: 0000000000000000 RBP: 00007efda94e2e6f R08: 0000000000000000 R09: 0000000000000000 R10: 00000002000007ff R11: 0000000000000246 R12: 0000000000000000 R13: 00007efda96c6128 R14: 00007efda96c6090 R15: 00007ffd28bf84e8