IPVS: stopping backup sync thread 15576 ... ====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc7-syzkaller-00209-g9528d418de4d #0 Not tainted ------------------------------------------------------ syz.0.2615/15575 is trying to acquire lock: ffffffff8fee0048 (rtnl_mutex){+.+.}-{4:4}, at: ip_mc_drop_socket+0x9b/0x290 net/ipv4/igmp.c:2718 but task is already holding lock: ffff88807cf7ad28 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_setsockopt+0x101/0xa00 net/smc/af_smc.c:3070 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&smc->clcsock_release_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735 smc_switch_to_fallback+0x2d/0xa00 net/smc/af_smc.c:903 smc_sendmsg+0x13d/0x520 net/smc/af_smc.c:2778 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg net/socket.c:726 [inline] __sys_sendto+0x488/0x4f0 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2200 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (sk_lock-AF_INET){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3625 lock_sock include/net/sock.h:1623 [inline] sockopt_lock_sock net/core/sock.c:1126 [inline] sockopt_lock_sock+0x54/0x70 net/core/sock.c:1117 do_ip_setsockopt+0x101/0x3680 net/ipv4/ip_sockglue.c:1078 ip_setsockopt+0x59/0xf0 net/ipv4/ip_sockglue.c:1417 udp_setsockopt+0x7d/0xd0 net/ipv4/udp.c:2997 do_sock_setsockopt+0x222/0x480 net/socket.c:2313 __sys_setsockopt+0x1a0/0x230 net/socket.c:2338 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2341 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (rtnl_mutex){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735 ip_mc_drop_socket+0x9b/0x290 net/ipv4/igmp.c:2718 inet_release+0xa3/0x280 net/ipv4/af_inet.c:422 __sock_release net/socket.c:640 [inline] sock_release+0x8e/0x1d0 net/socket.c:668 stop_sync_thread+0x285/0x720 net/netfilter/ipvs/ip_vs_sync.c:2004 do_ip_vs_set_ctl+0x4ec/0x11c0 net/netfilter/ipvs/ip_vs_ctl.c:2734 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424 tcp_setsockopt+0xa4/0x100 net/ipv4/tcp.c:4030 smc_setsockopt+0x1b4/0xa00 net/smc/af_smc.c:3078 do_sock_setsockopt+0x222/0x480 net/socket.c:2313 __sys_setsockopt+0x1a0/0x230 net/socket.c:2338 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2341 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 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.0.2615/15575: #0: ffff88807cf7ad28 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_setsockopt+0x101/0xa00 net/smc/af_smc.c:3070 stack backtrace: CPU: 0 UID: 0 PID: 15575 Comm: syz.0.2615 Not tainted 6.13.0-rc7-syzkaller-00209-g9528d418de4d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735 ip_mc_drop_socket+0x9b/0x290 net/ipv4/igmp.c:2718 inet_release+0xa3/0x280 net/ipv4/af_inet.c:422 __sock_release net/socket.c:640 [inline] sock_release+0x8e/0x1d0 net/socket.c:668 stop_sync_thread+0x285/0x720 net/netfilter/ipvs/ip_vs_sync.c:2004 do_ip_vs_set_ctl+0x4ec/0x11c0 net/netfilter/ipvs/ip_vs_ctl.c:2734 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424 tcp_setsockopt+0xa4/0x100 net/ipv4/tcp.c:4030 smc_setsockopt+0x1b4/0xa00 net/smc/af_smc.c:3078 do_sock_setsockopt+0x222/0x480 net/socket.c:2313 __sys_setsockopt+0x1a0/0x230 net/socket.c:2338 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2341 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4e3b385d29 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:00007f4e3c1c6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f4e3b575fa0 RCX: 00007f4e3b385d29 RDX: 000000000000048c RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f4e3b401b08 R08: 0000000000000018 R09: 0000000000000000 R10: 00000000200002c0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4e3b575fa0 R15: 00007ffea036f718