Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable ====================================================== WARNING: possible circular locking dependency detected 6.11.0-rc6-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.3027/20391 is trying to acquire lock: ffffffff8fc8bd48 (rtnl_mutex){+.+.}-{3:3}, at: ip_mroute_setsockopt+0x15b/0x1190 net/ipv4/ipmr.c:1369 but task is already holding lock: ffff888027dd2050 (&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: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:2779 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] __ia32_sys_sendto+0xdd/0x100 net/socket.c:2212 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #1 (sk_lock-AF_INET6){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 lock_sock_nested+0x48/0x100 net/core/sock.c:3543 do_ipv6_setsockopt+0xbf3/0x3630 net/ipv6/ipv6_sockglue.c:567 ipv6_setsockopt+0x5c/0x1a0 net/ipv6/ipv6_sockglue.c:993 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] __ia32_sys_setsockopt+0xb5/0xd0 net/socket.c:2353 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 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+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_mroute_setsockopt+0x15b/0x1190 net/ipv4/ipmr.c:1369 do_ip_setsockopt+0x129f/0x3cd0 net/ipv4/ip_sockglue.c:948 ip_setsockopt+0x63/0x100 net/ipv4/ip_sockglue.c:1417 smc_setsockopt+0x275/0xe50 net/smc/af_smc.c:3072 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] __ia32_sys_setsockopt+0xb5/0xd0 net/socket.c:2353 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 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_INET6 --> &smc->clcsock_release_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&smc->clcsock_release_lock); lock(sk_lock-AF_INET6); lock(&smc->clcsock_release_lock); lock(rtnl_mutex); *** DEADLOCK *** 1 lock held by syz.1.3027/20391: #0: ffff888027dd2050 (&smc->clcsock_release_lock){+.+.}-{3:3}, at: smc_setsockopt+0x1c3/0xe50 net/smc/af_smc.c:3064 stack backtrace: CPU: 0 UID: 0 PID: 20391 Comm: syz.1.3027 Not tainted 6.11.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 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_mroute_setsockopt+0x15b/0x1190 net/ipv4/ipmr.c:1369 do_ip_setsockopt+0x129f/0x3cd0 net/ipv4/ip_sockglue.c:948 ip_setsockopt+0x63/0x100 net/ipv4/ip_sockglue.c:1417 smc_setsockopt+0x275/0xe50 net/smc/af_smc.c:3072 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] __ia32_sys_setsockopt+0xb5/0xd0 net/socket.c:2353 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fe6579 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 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f578656c EFLAGS: 00000206 ORIG_RAX: 000000000000016e RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000000000 RDX: 00000000000000c9 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 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: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop