TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. FAT-fs (loop6): bogus number of reserved sectors FAT-fs (loop6): Can't find a valid FAT filesystem ====================================================== [ INFO: possible circular locking dependency detected ] 4.9.107-g42a730a #45 Not tainted ------------------------------------------------------- syz-executor0/12721 is trying to acquire lock: (sk_lock-AF_INET){+.+.+.}, at: [] lock_sock include/net/sock.h:1404 [inline] (sk_lock-AF_INET){+.+.+.}, at: [] set_mcast_if net/netfilter/ipvs/ip_vs_sync.c:1370 [inline] (sk_lock-AF_INET){+.+.+.}, at: [] make_send_sock net/netfilter/ipvs/ip_vs_sync.c:1490 [inline] (sk_lock-AF_INET){+.+.+.}, at: [] start_sync_thread+0x88b/0x1e80 net/netfilter/ipvs/ip_vs_sync.c:1885 but task is already holding lock: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (rtnl_mutex){+.+.+.}: lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756 __mutex_lock_common kernel/locking/mutex.c:521 [inline] mutex_lock_nested+0xc0/0x870 kernel/locking/mutex.c:621 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 mrtsock_destruct+0x3b/0x1e0 net/ipv4/ipmr.c:1231 ip_ra_control+0x2c2/0x420 net/ipv4/ip_sockglue.c:360 do_ip_setsockopt.isra.13+0x15ff/0x2b10 net/ipv4/ip_sockglue.c:1139 ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1242 raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:833 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706 SYSC_setsockopt net/socket.c:1772 [inline] SyS_setsockopt+0x166/0x260 net/socket.c:1751 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 entry_SYSCALL_64_after_swapgs+0x5d/0xdb -> #0 (sk_lock-AF_INET){+.+.+.}: check_prev_add kernel/locking/lockdep.c:1828 [inline] check_prevs_add kernel/locking/lockdep.c:1938 [inline] validate_chain kernel/locking/lockdep.c:2265 [inline] __lock_acquire+0x3019/0x4070 kernel/locking/lockdep.c:3345 lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756 lock_sock_nested+0xc6/0x120 net/core/sock.c:2511 lock_sock include/net/sock.h:1404 [inline] set_mcast_if net/netfilter/ipvs/ip_vs_sync.c:1370 [inline] make_send_sock net/netfilter/ipvs/ip_vs_sync.c:1490 [inline] start_sync_thread+0x88b/0x1e80 net/netfilter/ipvs/ip_vs_sync.c:1885 do_ip_vs_set_ctl+0x90f/0xbb0 net/netfilter/ipvs/ip_vs_ctl.c:2396 nf_sockopt net/netfilter/nf_sockopt.c:105 [inline] nf_setsockopt+0x6d/0xc0 net/netfilter/nf_sockopt.c:114 ip_setsockopt+0x9a/0xb0 net/ipv4/ip_sockglue.c:1249 tcp_setsockopt+0x88/0xe0 net/ipv4/tcp.c:2758 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706 SYSC_setsockopt net/socket.c:1772 [inline] SyS_setsockopt+0x166/0x260 net/socket.c:1751 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 entry_SYSCALL_64_after_swapgs+0x5d/0xdb other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(sk_lock-AF_INET); lock(rtnl_mutex); lock(sk_lock-AF_INET); *** DEADLOCK *** 2 locks held by syz-executor0/12721: #0: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 #1: (ipvs->sync_mutex){+.+.+.}, at: [] start_sync_thread+0x118/0x1e80 net/netfilter/ipvs/ip_vs_sync.c:1779 stack backtrace: CPU: 0 PID: 12721 Comm: syz-executor0 Not tainted 4.9.107-g42a730a #45 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801ba35f5a8 ffffffff81eb42a9 ffffffff855e7ba0 ffffffff8559cf30 ffffffff855e7ba0 ffff8801b745d0e8 ffff8801b745c800 ffff8801ba35f5f0 ffffffff814267ed 0000000000000001 00000000b745c800 0000000000000001 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_circular_bug.cold.51+0x1bd/0x27d kernel/locking/lockdep.c:1202 [] check_prev_add kernel/locking/lockdep.c:1828 [inline] [] check_prevs_add kernel/locking/lockdep.c:1938 [inline] [] validate_chain kernel/locking/lockdep.c:2265 [inline] [] __lock_acquire+0x3019/0x4070 kernel/locking/lockdep.c:3345 [] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756 [] lock_sock_nested+0xc6/0x120 net/core/sock.c:2511 [] lock_sock include/net/sock.h:1404 [inline] [] set_mcast_if net/netfilter/ipvs/ip_vs_sync.c:1370 [inline] [] make_send_sock net/netfilter/ipvs/ip_vs_sync.c:1490 [inline] [] start_sync_thread+0x88b/0x1e80 net/netfilter/ipvs/ip_vs_sync.c:1885 [] do_ip_vs_set_ctl+0x90f/0xbb0 net/netfilter/ipvs/ip_vs_ctl.c:2396 [] nf_sockopt net/netfilter/nf_sockopt.c:105 [inline] [] nf_setsockopt+0x6d/0xc0 net/netfilter/nf_sockopt.c:114 [] ip_setsockopt+0x9a/0xb0 net/ipv4/ip_sockglue.c:1249 [] tcp_setsockopt+0x88/0xe0 net/ipv4/tcp.c:2758 [] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706 [] SYSC_setsockopt net/socket.c:1772 [inline] [] SyS_setsockopt+0x166/0x260 net/socket.c:1751 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb IPVS: sync thread started: state = MASTER, mcast_ifn = lo, syncid = 0, id = 0 ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. FAT-fs (loop6): bogus number of reserved sectors FAT-fs (loop6): Can't find a valid FAT filesystem ISOFS: Unable to identify CD-ROM format. IPVS: sync thread started: state = MASTER, mcast_ifn = lo, syncid = 0, id = 0 ISOFS: Unable to identify CD-ROM format. syz-executor6 (12810) used greatest stack depth: 21824 bytes left TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. IPVS: sync thread started: state = MASTER, mcast_ifn = lo, syncid = 0, id = 0 IPVS: sync thread started: state = MASTER, mcast_ifn = lo, syncid = 0, id = 0 ISOFS: Unable to identify CD-ROM format. binder: 12861:12870 transaction failed 29189/-22, size 0-0 line 3018 ISOFS: Unable to identify CD-ROM format. binder: undelivered TRANSACTION_ERROR: 29189 IPVS: sync thread started: state = MASTER, mcast_ifn = lo, syncid = 0, id = 0 binder: 12898:12900 transaction failed 29189/-22, size 0-0 line 3018 IPVS: sync thread started: state = MASTER, mcast_ifn = lo, syncid = 0, id = 0 ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. binder: undelivered TRANSACTION_ERROR: 29189 binder: 12933:12935 transaction failed 29189/-22, size 0-0 line 3018 ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. binder: undelivered TRANSACTION_ERROR: 29189 EXT4-fs (loop6): bad geometry: block count 2048 exceeds size of device (2 blocks) TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. EXT4-fs (loop6): bad geometry: block count 2048 exceeds size of device (2 blocks) capability: warning: `syz-executor7' uses deprecated v2 capabilities in a way that may be insecure ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. EXT4-fs (loop6): bad geometry: block count 2048 exceeds size of device (2 blocks) ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. EXT4-fs (loop6): bad geometry: block count 2048 exceeds size of device (2 blocks) TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. EXT4-fs (loop6): bad geometry: block count 2048 exceeds size of device (2 blocks) ISOFS: Unable to identify CD-ROM format. ISOFS: Unable to identify CD-ROM format. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=28005 sclass=netlink_route_socket pig=13072 comm=syz-executor6 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=28005 sclass=netlink_route_socket pig=13073 comm=syz-executor3 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=28005 sclass=netlink_route_socket pig=13077 comm=syz-executor5