Hello, syzbot found the following issue on: HEAD commit: 3226607302ca selftests: net: change shebang to bash in amt.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=12a2683e980000 kernel config: https://syzkaller.appspot.com/x/.config?x=e78fc116033e0ab7 dashboard link: https://syzkaller.appspot.com/bug?extid=e929093395ec65f969c7 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/125c85863435/disk-32266073.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/4477ecab2e1f/vmlinux-32266073.xz kernel image: https://storage.googleapis.com/syzbot-assets/43e28f6ce879/bzImage-32266073.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e929093395ec65f969c7@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc4-syzkaller-00837-g3226607302ca #0 Not tainted ------------------------------------------------------ syz-executor.4/10811 is trying to acquire lock: ffffffff8f5e6f48 (rtnl_mutex){+.+.}-{3:3}, at: start_sync_thread+0xdc/0x2dc0 net/netfilter/ipvs/ip_vs_sync.c:1761 but task is already holding lock: ffff88805ba95750 (&smc->clcsock_release_lock){+.+.}-{3:3}, at: smc_setsockopt+0x1c3/0xe50 net/smc/af_smc.c:3064 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:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 smc_switch_to_fallback+0x35/0xd00 net/smc/af_smc.c:902 smc_sendmsg+0x11f/0x530 net/smc/af_smc.c:2779 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2200 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:5754 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:2312 __sys_setsockopt+0x1ae/0x250 net/socket.c:2335 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2341 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:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 start_sync_thread+0xdc/0x2dc0 net/netfilter/ipvs/ip_vs_sync.c:1761 do_ip_vs_set_ctl+0x442/0x13d0 net/netfilter/ipvs/ip_vs_ctl.c:2732 nf_setsockopt+0x295/0x2c0 net/netfilter/nf_sockopt.c:101 smc_setsockopt+0x275/0xe50 net/smc/af_smc.c:3072 do_sock_setsockopt+0x3af/0x720 net/socket.c:2312 __sys_setsockopt+0x1ae/0x250 net/socket.c:2335 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2341 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-executor.4/10811: #0: ffff88805ba95750 (&smc->clcsock_release_lock){+.+.}-{3:3}, at: smc_setsockopt+0x1c3/0xe50 net/smc/af_smc.c:3064 stack backtrace: CPU: 0 PID: 10811 Comm: syz-executor.4 Not tainted 6.10.0-rc4-syzkaller-00837-g3226607302ca #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 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+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 start_sync_thread+0xdc/0x2dc0 net/netfilter/ipvs/ip_vs_sync.c:1761 do_ip_vs_set_ctl+0x442/0x13d0 net/netfilter/ipvs/ip_vs_ctl.c:2732 nf_setsockopt+0x295/0x2c0 net/netfilter/nf_sockopt.c:101 smc_setsockopt+0x275/0xe50 net/smc/af_smc.c:3072 do_sock_setsockopt+0x3af/0x720 net/socket.c:2312 __sys_setsockopt+0x1ae/0x250 net/socket.c:2335 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2341 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: 0033:0x7f42d8a7d0a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f42d98870c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f42d8bb3f80 RCX: 00007f42d8a7d0a9 RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f42d8aec074 R08: 0000000000000018 R09: 0000000000000000 R10: 0000000020000200 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f42d8bb3f80 R15: 00007ffde628d3a8 </TASK> --- This report is generated by a bot. 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