IPVS: stopping backup sync thread 11445 ... ====================================================== WARNING: possible circular locking dependency detected 6.11.0-rc2-syzkaller-00393-ga9c60712d71f #0 Not tainted ------------------------------------------------------ syz.3.2107/13085 is trying to acquire lock: ffffffff8fc81f48 (rtnl_mutex){+.+.}-{3:3}, at: ip_mc_drop_socket+0x81/0x280 net/ipv4/igmp.c:2702 but task is already holding lock: ffff88801f3d5750 (&smc->clcsock_release_lock){+.+.}-{3:3}, at: smc_setsockopt+0x1c3/0xe50 net/smc/af_smc.c:3056 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&smc->clcsock_release_lock){+.+.}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 smc_switch_to_fallback+0x35/0xdb0 net/smc/af_smc.c:902 smc_sendmsg+0x11f/0x530 net/smc/af_smc.c:2771 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2204 __do_sys_sendto net/socket.c:2216 [inline] __se_sys_sendto net/socket.c:2212 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2212 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (sk_lock-AF_INET){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 lock_sock_nested+0x48/0x100 net/core/sock.c:3543 do_ip_setsockopt+0x1a2d/0x3cd0 net/ipv4/ip_sockglue.c:1078 ip_setsockopt+0x63/0x100 net/ipv4/ip_sockglue.c:1417 do_sock_setsockopt+0x3af/0x720 net/socket.c:2324 __sys_setsockopt+0x1ae/0x250 net/socket.c:2347 __do_sys_setsockopt net/socket.c:2356 [inline] __se_sys_setsockopt net/socket.c:2353 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2353 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (rtnl_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 ip_mc_drop_socket+0x81/0x280 net/ipv4/igmp.c:2702 inet_release+0x96/0x200 net/ipv4/af_inet.c:424 __sock_release net/socket.c:659 [inline] sock_release+0x82/0x150 net/socket.c:687 stop_sync_thread+0x4e6/0x5e0 net/netfilter/ipvs/ip_vs_sync.c:2004 do_ip_vs_set_ctl+0x47b/0x13d0 net/netfilter/ipvs/ip_vs_ctl.c:2734 nf_setsockopt+0x295/0x2c0 net/netfilter/nf_sockopt.c:101 smc_setsockopt+0x275/0xe50 net/smc/af_smc.c:3064 do_sock_setsockopt+0x3af/0x720 net/socket.c:2324 __sys_setsockopt+0x1ae/0x250 net/socket.c:2347 __do_sys_setsockopt net/socket.c:2356 [inline] __se_sys_setsockopt net/socket.c:2353 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2353 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: rtnl_mutex --> sk_lock-AF_INET --> &smc->clcsock_release_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&smc->clcsock_release_lock); lock(sk_lock-AF_INET); lock(&smc->clcsock_release_lock); lock(rtnl_mutex); *** DEADLOCK *** 1 lock held by syz.3.2107/13085: #0: ffff88801f3d5750 (&smc->clcsock_release_lock){+.+.}-{3:3}, at: smc_setsockopt+0x1c3/0xe50 net/smc/af_smc.c:3056 stack backtrace: CPU: 0 UID: 0 PID: 13085 Comm: syz.3.2107 Not tainted 6.11.0-rc2-syzkaller-00393-ga9c60712d71f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186 check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 ip_mc_drop_socket+0x81/0x280 net/ipv4/igmp.c:2702 inet_release+0x96/0x200 net/ipv4/af_inet.c:424 __sock_release net/socket.c:659 [inline] sock_release+0x82/0x150 net/socket.c:687 stop_sync_thread+0x4e6/0x5e0 net/netfilter/ipvs/ip_vs_sync.c:2004 do_ip_vs_set_ctl+0x47b/0x13d0 net/netfilter/ipvs/ip_vs_ctl.c:2734 nf_setsockopt+0x295/0x2c0 net/netfilter/nf_sockopt.c:101 smc_setsockopt+0x275/0xe50 net/smc/af_smc.c:3064 do_sock_setsockopt+0x3af/0x720 net/socket.c:2324 __sys_setsockopt+0x1ae/0x250 net/socket.c:2347 __do_sys_setsockopt net/socket.c:2356 [inline] __se_sys_setsockopt net/socket.c:2353 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2353 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f77c39799b9 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:00007f77c33ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f77c3b16058 RCX: 00007f77c39799b9 RDX: 000000000000048c RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f77c39e78d8 R08: 0000000000000018 R09: 0000000000000000 R10: 00000000200011c0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f77c3b16058 R15: 00007ffccb920e68