======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc3-syzkaller #0 Not tainted
------------------------------------------------------
syz.0.15/4035 is trying to acquire lock:
ffff888117278258 (sk_lock-AF_INET){+.+.}-{0:0}, at: do_ip_setsockopt+0x91d/0x10c0 net/ipv4/ip_sockglue.c:1078

but task is already holding lock:
ffffffff843aa278 (rtnl_mutex){+.+.}-{3:3}, at: do_ip_setsockopt+0x914/0x10c0 net/ipv4/ip_sockglue.c:1077

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (rtnl_mutex){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x99/0x9a0 kernel/locking/mutex.c:752
       smc_vlan_by_tcpsk+0x15b/0x200 net/smc/smc_core.c:1853
       __smc_connect+0xd3/0x610 net/smc/af_smc.c:1522
       smc_connect+0x250/0x2d0 net/smc/af_smc.c:1702
       __sys_connect_file net/socket.c:2049 [inline]
       __sys_connect+0x1c1/0x1f0 net/socket.c:2066
       __do_sys_connect net/socket.c:2076 [inline]
       __se_sys_connect net/socket.c:2073 [inline]
       __x64_sys_connect+0x15/0x20 net/socket.c:2073
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xa0/0x1b0 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (sk_lock-AF_INET){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x11fe/0x2490 kernel/locking/lockdep.c:5137
       lock_acquire+0xeb/0x270 kernel/locking/lockdep.c:5754
       lock_sock_nested net/core/sock.c:3543 [inline]
       lock_sock include/net/sock.h:1602 [inline]
       sockopt_lock_sock+0x4b/0x90 net/core/sock.c:1061
       do_ip_setsockopt+0x91d/0x10c0 net/ipv4/ip_sockglue.c:1078
       ip_setsockopt+0x39/0x80 net/ipv4/ip_sockglue.c:1417
       do_sock_setsockopt net/socket.c:2312 [inline]
       __sys_setsockopt+0xef/0x110 net/socket.c:2335
       __do_sys_setsockopt net/socket.c:2344 [inline]
       __se_sys_setsockopt net/socket.c:2341 [inline]
       __x64_sys_setsockopt+0x1c/0x30 net/socket.c:2341
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xa0/0x1b0 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(rtnl_mutex);
                               lock(sk_lock-AF_INET);
                               lock(rtnl_mutex);
  lock(sk_lock-AF_INET);

 *** DEADLOCK ***

1 lock held by syz.0.15/4035:
 #0: ffffffff843aa278 (rtnl_mutex){+.+.}-{3:3}, at: do_ip_setsockopt+0x914/0x10c0 net/ipv4/ip_sockglue.c:1077

stack backtrace:
CPU: 1 PID: 4035 Comm: syz.0.15 Not tainted 6.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xa3/0x100 lib/dump_stack.c:114
 check_noncircular+0x119/0x140 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x11fe/0x2490 kernel/locking/lockdep.c:5137
 lock_acquire+0xeb/0x270 kernel/locking/lockdep.c:5754
 lock_sock_nested net/core/sock.c:3543 [inline]
 lock_sock include/net/sock.h:1602 [inline]
 sockopt_lock_sock+0x4b/0x90 net/core/sock.c:1061
 do_ip_setsockopt+0x91d/0x10c0 net/ipv4/ip_sockglue.c:1078
 ip_setsockopt+0x39/0x80 net/ipv4/ip_sockglue.c:1417
 do_sock_setsockopt net/socket.c:2312 [inline]
 __sys_setsockopt+0xef/0x110 net/socket.c:2335
 __do_sys_setsockopt net/socket.c:2344 [inline]
 __se_sys_setsockopt net/socket.c:2341 [inline]
 __x64_sys_setsockopt+0x1c/0x30 net/socket.c:2341
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xa0/0x1b0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0537b79e79
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f05388e6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f0537d15f80 RCX: 00007f0537b79e79
RDX: 0000000000000023 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007f0537be793e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0537d15f80 R15: 00007ffe7c128c78
 </TASK>