======================================================
WARNING: possible circular locking dependency detected
6.4.0-rc6-syzkaller-01415-g98e95872f2b8 #0 Not tainted
------------------------------------------------------
syz-executor.4/8288 is trying to acquire lock:
ffff888079b23230 (msk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_diag_get_info+0x1ae/0x380 net/mptcp/mptcp_diag.c:224

but task is already holding lock:
ffffc9000130ca38 (&h->lhash2[i].lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline]
ffffc9000130ca38 (&h->lhash2[i].lock){+.+.}-{2:2}, at: mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:98 [inline]
ffffc9000130ca38 (&h->lhash2[i].lock){+.+.}-{2:2}, at: mptcp_diag_dump+0x838/0x1330 net/mptcp/mptcp_diag.c:197

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&h->lhash2[i].lock){+.+.}-{2:2}:
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
       spin_lock include/linux/spinlock.h:350 [inline]
       inet_unhash+0x3ad/0x700 net/ipv4/inet_hashtables.c:780
       tcp_set_state+0x19b/0x7e0 net/ipv4/tcp.c:2667
       __mptcp_close_ssk+0x714/0x900 net/mptcp/protocol.c:2412
       mptcp_destroy_common+0x169/0x650 net/mptcp/protocol.c:3271
       mptcp_destroy+0x84/0x110 net/mptcp/protocol.c:3298
       __mptcp_destroy_sock+0xf6/0x3c0 net/mptcp/protocol.c:2928
       __mptcp_close+0x7c1/0xac0 net/mptcp/protocol.c:3026
       mptcp_close+0x28/0xf0 net/mptcp/protocol.c:3041
       inet_release+0x132/0x270 net/ipv4/af_inet.c:427
       inet6_release+0x50/0x70 net/ipv6/af_inet6.c:480
       __sock_release+0xcd/0x290 net/socket.c:653
       sock_close+0x1c/0x20 net/socket.c:1385
       __fput+0x27c/0xa90 fs/file_table.c:321
       task_work_run+0x16f/0x270 kernel/task_work.c:179
       resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
       exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
       exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204
       __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
       syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297
       do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #1 (k-sk_lock-AF_INET6/1){+.+.}-{0:0}:
       lock_sock_nested+0x3a/0xf0 net/core/sock.c:3517
       mptcp_subflow_create_socket+0x176/0xed0 net/mptcp/subflow.c:1671
       __mptcp_socket_create net/mptcp/protocol.c:89 [inline]
       __mptcp_nmpc_socket net/mptcp/protocol.c:123 [inline]
       __mptcp_nmpc_socket+0x1b0/0x7b0 net/mptcp/protocol.c:111
       mptcp_pm_nl_create_listen_socket+0x335/0x5b0 net/mptcp/pm_netlink.c:1035
       mptcp_nl_cmd_add_addr+0x2d9/0x9d0 net/mptcp/pm_netlink.c:1339
       genl_family_rcv_msg_doit.isra.0+0x1e6/0x2d0 net/netlink/genetlink.c:970
       genl_family_rcv_msg net/netlink/genetlink.c:1050 [inline]
       genl_rcv_msg+0x4ff/0x7e0 net/netlink/genetlink.c:1067
       netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2548
       genl_rcv+0x28/0x40 net/netlink/genetlink.c:1078
       netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
       netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
       netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1913
       sock_sendmsg_nosec net/socket.c:724 [inline]
       sock_sendmsg+0xde/0x190 net/socket.c:747
       ____sys_sendmsg+0x733/0x920 net/socket.c:2493
       ___sys_sendmsg+0x110/0x1b0 net/socket.c:2547
       __sys_sendmsg+0xf7/0x1c0 net/socket.c:2576
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (msk_lock-AF_INET){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3113 [inline]
       check_prevs_add kernel/locking/lockdep.c:3232 [inline]
       validate_chain kernel/locking/lockdep.c:3847 [inline]
       __lock_acquire+0x2fcd/0x5f30 kernel/locking/lockdep.c:5088
       lock_acquire kernel/locking/lockdep.c:5705 [inline]
       lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5670
       lock_sock_fast include/net/sock.h:1742 [inline]
       mptcp_diag_fill_info+0x454/0x9c0 net/mptcp/sockopt.c:930
       mptcp_diag_get_info+0x1ae/0x380 net/mptcp/mptcp_diag.c:224
       inet_sk_diag_fill+0x1258/0x1fd0 net/ipv4/inet_diag.c:342
       sk_diag_dump net/mptcp/mptcp_diag.c:24 [inline]
       sk_diag_dump net/mptcp/mptcp_diag.c:16 [inline]
       mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:125 [inline]
       mptcp_diag_dump+0xc5e/0x1330 net/mptcp/mptcp_diag.c:197
       __inet_diag_dump+0x114/0x2e0 net/ipv4/inet_diag.c:1179
       inet_diag_dump_compat+0x209/0x290 net/ipv4/inet_diag.c:1287
       netlink_dump+0x570/0xc50 net/netlink/af_netlink.c:2268
       __netlink_dump_start+0x6c0/0x9b0 net/netlink/af_netlink.c:2375
       netlink_dump_start include/linux/netlink.h:330 [inline]
       inet_diag_rcv_msg_compat+0x26d/0x2d0 net/ipv4/inet_diag.c:1321
       __sock_diag_cmd net/core/sock_diag.c:240 [inline]
       sock_diag_rcv_msg+0x2eb/0x440 net/core/sock_diag.c:269
       netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2548
       sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:280
       netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
       netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
       netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1913
       sock_sendmsg_nosec net/socket.c:724 [inline]
       sock_sendmsg+0xde/0x190 net/socket.c:747
       splice_to_socket+0x964/0xee0 fs/splice.c:915
       do_splice_from fs/splice.c:967 [inline]
       direct_splice_actor+0x114/0x180 fs/splice.c:1155
       splice_direct_to_actor+0x34a/0x9c0 fs/splice.c:1101
       do_splice_direct+0x1ad/0x280 fs/splice.c:1207
       do_sendfile+0xb19/0x12c0 fs/read_write.c:1254
       __do_sys_sendfile64 fs/read_write.c:1322 [inline]
       __se_sys_sendfile64 fs/read_write.c:1308 [inline]
       __x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1308
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

Chain exists of:
  msk_lock-AF_INET --> k-sk_lock-AF_INET6/1 --> &h->lhash2[i].lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&h->lhash2[i].lock);
                               lock(k-sk_lock-AF_INET6/1);
                               lock(&h->lhash2[i].lock);
  lock(msk_lock-AF_INET);

 *** DEADLOCK ***

6 locks held by syz-executor.4/8288:
 #0: ffffffff8e125408 (sock_diag_mutex){+.+.}-{3:3}, at: sock_diag_rcv+0x1b/0x40 net/core/sock_diag.c:279
 #1: ffffffff8e125588 (sock_diag_table_mutex){+.+.}-{3:3}, at: sock_diag_rcv_msg net/core/sock_diag.c:259 [inline]
 #1: ffffffff8e125588 (sock_diag_table_mutex){+.+.}-{3:3}, at: sock_diag_rcv_msg+0x2d2/0x440 net/core/sock_diag.c:248
 #2: ffff88807df17688 (nlk_cb_mutex-SOCK_DIAG){+.+.}-{3:3}, at: netlink_dump+0xbe/0xc50 net/netlink/af_netlink.c:2215
 #3: ffffffff8e29a628 (inet_diag_table_mutex){+.+.}-{3:3}, at: inet_diag_lock_handler+0x6e/0x100 net/ipv4/inet_diag.c:63
 #4: ffffffff8c7990c0 (rcu_read_lock){....}-{1:2}, at: mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:95 [inline]
 #4: ffffffff8c7990c0 (rcu_read_lock){....}-{1:2}, at: mptcp_diag_dump+0x7c8/0x1330 net/mptcp/mptcp_diag.c:197
 #5: ffffc9000130ca38 (&h->lhash2[i].lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline]
 #5: ffffc9000130ca38 (&h->lhash2[i].lock){+.+.}-{2:2}, at: mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:98 [inline]
 #5: ffffc9000130ca38 (&h->lhash2[i].lock){+.+.}-{2:2}, at: mptcp_diag_dump+0x838/0x1330 net/mptcp/mptcp_diag.c:197

stack backtrace:
CPU: 0 PID: 8288 Comm: syz-executor.4 Not tainted 6.4.0-rc6-syzkaller-01415-g98e95872f2b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2188
 check_prev_add kernel/locking/lockdep.c:3113 [inline]
 check_prevs_add kernel/locking/lockdep.c:3232 [inline]
 validate_chain kernel/locking/lockdep.c:3847 [inline]
 __lock_acquire+0x2fcd/0x5f30 kernel/locking/lockdep.c:5088
 lock_acquire kernel/locking/lockdep.c:5705 [inline]
 lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5670
 lock_sock_fast include/net/sock.h:1742 [inline]
 mptcp_diag_fill_info+0x454/0x9c0 net/mptcp/sockopt.c:930
 mptcp_diag_get_info+0x1ae/0x380 net/mptcp/mptcp_diag.c:224
 inet_sk_diag_fill+0x1258/0x1fd0 net/ipv4/inet_diag.c:342
 sk_diag_dump net/mptcp/mptcp_diag.c:24 [inline]
 sk_diag_dump net/mptcp/mptcp_diag.c:16 [inline]
 mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:125 [inline]
 mptcp_diag_dump+0xc5e/0x1330 net/mptcp/mptcp_diag.c:197
 __inet_diag_dump+0x114/0x2e0 net/ipv4/inet_diag.c:1179
 inet_diag_dump_compat+0x209/0x290 net/ipv4/inet_diag.c:1287
 netlink_dump+0x570/0xc50 net/netlink/af_netlink.c:2268
 __netlink_dump_start+0x6c0/0x9b0 net/netlink/af_netlink.c:2375
 netlink_dump_start include/linux/netlink.h:330 [inline]
 inet_diag_rcv_msg_compat+0x26d/0x2d0 net/ipv4/inet_diag.c:1321
 __sock_diag_cmd net/core/sock_diag.c:240 [inline]
 sock_diag_rcv_msg+0x2eb/0x440 net/core/sock_diag.c:269
 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2548
 sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:280
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1913
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:747
 splice_to_socket+0x964/0xee0 fs/splice.c:915
 do_splice_from fs/splice.c:967 [inline]
 direct_splice_actor+0x114/0x180 fs/splice.c:1155
 splice_direct_to_actor+0x34a/0x9c0 fs/splice.c:1101
 do_splice_direct+0x1ad/0x280 fs/splice.c:1207
 do_sendfile+0xb19/0x12c0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3294c8c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3295a4c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f3294dabf80 RCX: 00007f3294c8c389
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 000000000000000a
RBP: 00007f3294cd7493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000021fd1ee9 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd6a884aef R14: 00007f3295a4c300 R15: 0000000000022000
 </TASK>
BUG: sleeping function called from invalid context at net/core/sock.c:3549
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 8288, name: syz-executor.4
preempt_count: 1, expected: 0
RCU nest depth: 1, expected: 0
INFO: lockdep is turned off.
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 0 PID: 8288 Comm: syz-executor.4 Not tainted 6.4.0-rc6-syzkaller-01415-g98e95872f2b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x136/0x150 lib/dump_stack.c:106
 __might_resched+0x358/0x580 kernel/sched/core.c:10153
 __lock_sock_fast+0x25/0xe0 net/core/sock.c:3549
 lock_sock_fast include/net/sock.h:1744 [inline]
 mptcp_diag_fill_info+0x45c/0x9c0 net/mptcp/sockopt.c:930
 mptcp_diag_get_info+0x1ae/0x380 net/mptcp/mptcp_diag.c:224
 inet_sk_diag_fill+0x1258/0x1fd0 net/ipv4/inet_diag.c:342
 sk_diag_dump net/mptcp/mptcp_diag.c:24 [inline]
 sk_diag_dump net/mptcp/mptcp_diag.c:16 [inline]
 mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:125 [inline]
 mptcp_diag_dump+0xc5e/0x1330 net/mptcp/mptcp_diag.c:197
 __inet_diag_dump+0x114/0x2e0 net/ipv4/inet_diag.c:1179
 inet_diag_dump_compat+0x209/0x290 net/ipv4/inet_diag.c:1287
 netlink_dump+0x570/0xc50 net/netlink/af_netlink.c:2268
 __netlink_dump_start+0x6c0/0x9b0 net/netlink/af_netlink.c:2375
 netlink_dump_start include/linux/netlink.h:330 [inline]
 inet_diag_rcv_msg_compat+0x26d/0x2d0 net/ipv4/inet_diag.c:1321
 __sock_diag_cmd net/core/sock_diag.c:240 [inline]
 sock_diag_rcv_msg+0x2eb/0x440 net/core/sock_diag.c:269
 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2548
 sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:280
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1913
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:747
 splice_to_socket+0x964/0xee0 fs/splice.c:915
 do_splice_from fs/splice.c:967 [inline]
 direct_splice_actor+0x114/0x180 fs/splice.c:1155
 splice_direct_to_actor+0x34a/0x9c0 fs/splice.c:1101
 do_splice_direct+0x1ad/0x280 fs/splice.c:1207
 do_sendfile+0xb19/0x12c0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3294c8c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3295a4c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f3294dabf80 RCX: 00007f3294c8c389
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 000000000000000a
RBP: 00007f3294cd7493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000021fd1ee9 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd6a884aef R14: 00007f3295a4c300 R15: 0000000000022000
 </TASK>