IPVS: stopping backup sync thread 6435 ... ====================================================== WARNING: possible circular locking dependency detected 6.11.0-rc3-syzkaller-00007-gd74da846046a #0 Not tainted ------------------------------------------------------ syz.2.947/8769 is trying to acquire lock: ffffffff8fa0cfa8 (rtnl_mutex){+.+.}-{3:3}, at: ip_mc_drop_socket+0x9b/0x290 net/ipv4/igmp.c:2702 but task is already holding lock: ffff88805b0c4150 (&smc->clcsock_release_lock){+.+.}-{3:3}, at: smc_setsockopt+0x101/0xc00 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}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 smc_switch_to_fallback+0x2d/0xa00 net/smc/af_smc.c:902 smc_sendmsg+0x13d/0x520 net/smc/af_smc.c:2779 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x47f/0x4e0 net/socket.c:2204 __do_sys_sendto net/socket.c:2216 [inline] __se_sys_sendto net/socket.c:2212 [inline] __ia32_sys_sendto+0xdd/0x1b0 net/socket.c:2212 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #1 (sk_lock-AF_INET){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3543 lock_sock include/net/sock.h:1607 [inline] sockopt_lock_sock net/core/sock.c:1061 [inline] sockopt_lock_sock+0x54/0x70 net/core/sock.c:1052 do_ip_setsockopt+0x101/0x38c0 net/ipv4/ip_sockglue.c:1078 ip_setsockopt+0x59/0xf0 net/ipv4/ip_sockglue.c:1417 raw_setsockopt+0xb8/0x290 net/ipv4/raw.c:845 do_sock_setsockopt+0x222/0x480 net/socket.c:2324 __sys_setsockopt+0x1a4/0x270 net/socket.c:2347 __do_sys_setsockopt net/socket.c:2356 [inline] __se_sys_setsockopt net/socket.c:2353 [inline] __ia32_sys_setsockopt+0xbc/0x160 net/socket.c:2353 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #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 kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142 lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 ip_mc_drop_socket+0x9b/0x290 net/ipv4/igmp.c:2702 inet_release+0xa3/0x280 net/ipv4/af_inet.c:424 __sock_release net/socket.c:659 [inline] sock_release+0x8e/0x1d0 net/socket.c:687 stop_sync_thread+0x285/0x720 net/netfilter/ipvs/ip_vs_sync.c:2004 do_ip_vs_set_ctl+0x532/0x1070 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:3768 smc_setsockopt+0x1b4/0xc00 net/smc/af_smc.c:3072 do_sock_setsockopt+0x222/0x480 net/socket.c:2324 __sys_setsockopt+0x1a4/0x270 net/socket.c:2347 __do_sys_setsockopt net/socket.c:2356 [inline] __se_sys_setsockopt net/socket.c:2353 [inline] __ia32_sys_setsockopt+0xbc/0x160 net/socket.c:2353 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e 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.2.947/8769: #0: ffff88805b0c4150 (&smc->clcsock_release_lock){+.+.}-{3:3}, at: smc_setsockopt+0x101/0xc00 net/smc/af_smc.c:3064 stack backtrace: CPU: 0 UID: 0 PID: 8769 Comm: syz.2.947 Not tainted 6.11.0-rc3-syzkaller-00007-gd74da846046a #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 check_noncircular+0x31a/0x400 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 kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142 lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 ip_mc_drop_socket+0x9b/0x290 net/ipv4/igmp.c:2702 inet_release+0xa3/0x280 net/ipv4/af_inet.c:424 __sock_release net/socket.c:659 [inline] sock_release+0x8e/0x1d0 net/socket.c:687 stop_sync_thread+0x285/0x720 net/netfilter/ipvs/ip_vs_sync.c:2004 do_ip_vs_set_ctl+0x532/0x1070 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:3768 smc_setsockopt+0x1b4/0xc00 net/smc/af_smc.c:3072 do_sock_setsockopt+0x222/0x480 net/socket.c:2324 __sys_setsockopt+0x1a4/0x270 net/socket.c:2347 __do_sys_setsockopt net/socket.c:2356 [inline] __se_sys_setsockopt net/socket.c:2353 [inline] __ia32_sys_setsockopt+0xbc/0x160 net/socket.c:2353 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf73fe579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f56e556c EFLAGS: 00000296 ORIG_RAX: 000000000000016e RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000000000 RDX: 000000000000048c RSI: 00000000200003c0 RDI: 0000000000000018 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi