====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc1-next-20241205-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.52/6144 is trying to acquire lock: ffffffff8fcb8188 (rtnl_mutex){+.+.}-{4:4}, at: do_ip_setsockopt+0x127d/0x3cd0 net/ipv4/ip_sockglue.c:1077 but task is already holding lock: ffff88805d778aa8 (&smc->clcsock_release_lock){+.+.}-{4:4}, 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){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 smc_switch_to_fallback+0x35/0xd90 net/smc/af_smc.c:903 smc_sendmsg+0x11f/0x530 net/smc/af_smc.c:2771 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 __sys_sendto+0x363/0x4c0 net/socket.c:2197 __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:5849 lock_sock_nested+0x48/0x100 net/core/sock.c:3622 lock_sock include/net/sock.h:1617 [inline] gtp_encap_enable_socket+0x2ce/0x5c0 drivers/net/gtp.c:1672 gtp_encap_enable drivers/net/gtp.c:1706 [inline] gtp_newlink+0x59f/0xf60 drivers/net/gtp.c:1509 rtnl_newlink_create+0x2ee/0xa40 net/core/rtnetlink.c:3786 __rtnl_newlink net/core/rtnetlink.c:3896 [inline] rtnl_newlink+0x1b40/0x20e0 net/core/rtnetlink.c:4009 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6919 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2542 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmsg+0x269/0x350 net/socket.c:2669 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){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 do_ip_setsockopt+0x127d/0x3cd0 net/ipv4/ip_sockglue.c:1077 ip_setsockopt+0x63/0x100 net/ipv4/ip_sockglue.c:1417 smc_setsockopt+0x275/0xe50 net/smc/af_smc.c:3064 do_sock_setsockopt+0x3af/0x720 net/socket.c:2313 __sys_setsockopt net/socket.c:2338 [inline] __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0x1ee/0x280 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.1.52/6144: #0: ffff88805d778aa8 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_setsockopt+0x1c3/0xe50 net/smc/af_smc.c:3056 stack backtrace: CPU: 1 UID: 0 PID: 6144 Comm: syz.1.52 Not tainted 6.13.0-rc1-next-20241205-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 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+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 do_ip_setsockopt+0x127d/0x3cd0 net/ipv4/ip_sockglue.c:1077 ip_setsockopt+0x63/0x100 net/ipv4/ip_sockglue.c:1417 smc_setsockopt+0x275/0xe50 net/smc/af_smc.c:3064 do_sock_setsockopt+0x3af/0x720 net/socket.c:2313 __sys_setsockopt net/socket.c:2338 [inline] __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0x1ee/0x280 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: 0033:0x7f057237fed9 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:00007f057311d058 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f0572545fa0 RCX: 00007f057237fed9 RDX: 0000000000000030 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 00007f05723f3cc8 R08: 0000000000000410 R09: 0000000000000000 R10: 0000000020000440 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0572545fa0 R15: 00007ffd99a7cc88