====================================================== WARNING: possible circular locking dependency detected 4.17.0-rc2+ #22 Not tainted ------------------------------------------------------ syz-executor1/6602 is trying to acquire lock: (ptrval) (&mm->mmap_sem){++++}, at: __might_fault+0xfb/0x1e0 mm/memory.c:4554 but task is already holding lock: (ptrval) (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1469 [inline] (ptrval) (sk_lock-AF_INET6){+.+.}, at: do_ipv6_setsockopt.isra.9+0x5ba/0x4680 net/ipv6/ipv6_sockglue.c:167 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sk_lock-AF_INET6){+.+.}: lock_sock_nested+0xd0/0x120 net/core/sock.c:2844 lock_sock include/net/sock.h:1469 [inline] tcp_mmap+0x1c7/0x14f0 net/ipv4/tcp.c:1759 sock_mmap+0x8e/0xc0 net/socket.c:1144 call_mmap include/linux/fs.h:1789 [inline] mmap_region+0xd13/0x1820 mm/mmap.c:1723 do_mmap+0xc79/0x11d0 mm/mmap.c:1494 do_mmap_pgoff include/linux/mm.h:2237 [inline] vm_mmap_pgoff+0x1fb/0x2a0 mm/util.c:357 ksys_mmap_pgoff+0x4c9/0x640 mm/mmap.c:1544 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline] __x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&mm->mmap_sem){++++}: lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 __might_fault+0x155/0x1e0 mm/memory.c:4555 _copy_from_user+0x30/0x150 lib/usercopy.c:10 copy_from_user include/linux/uaccess.h:147 [inline] ipv6_flowlabel_opt+0x258/0x3310 net/ipv6/ip6_flowlabel.c:529 do_ipv6_setsockopt.isra.9+0xb81/0x4680 net/ipv6/ipv6_sockglue.c:803 ipv6_setsockopt+0xbd/0x170 net/ipv6/ipv6_sockglue.c:922 udpv6_setsockopt+0x62/0xa0 net/ipv6/udp.c:1445 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3042 __sys_setsockopt+0x1bd/0x390 net/socket.c:1903 __do_sys_setsockopt net/socket.c:1914 [inline] __se_sys_setsockopt net/socket.c:1911 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_INET6); lock(&mm->mmap_sem); lock(sk_lock-AF_INET6); lock(&mm->mmap_sem); *** DEADLOCK *** 1 lock held by syz-executor1/6602: #0: (ptrval) (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1469 [inline] #0: (ptrval) (sk_lock-AF_INET6){+.+.}, at: do_ipv6_setsockopt.isra.9+0x5ba/0x4680 net/ipv6/ipv6_sockglue.c:167 stack backtrace: CPU: 1 PID: 6602 Comm: syz-executor1 Not tainted 4.17.0-rc2+ #22 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_circular_bug.isra.36.cold.54+0x1bd/0x27d kernel/locking/lockdep.c:1223 check_prev_add kernel/locking/lockdep.c:1863 [inline] check_prevs_add kernel/locking/lockdep.c:1976 [inline] validate_chain kernel/locking/lockdep.c:2417 [inline] __lock_acquire+0x343e/0x5140 kernel/locking/lockdep.c:3431 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 __might_fault+0x155/0x1e0 mm/memory.c:4555 _copy_from_user+0x30/0x150 lib/usercopy.c:10 copy_from_user include/linux/uaccess.h:147 [inline] ipv6_flowlabel_opt+0x258/0x3310 net/ipv6/ip6_flowlabel.c:529 do_ipv6_setsockopt.isra.9+0xb81/0x4680 net/ipv6/ipv6_sockglue.c:803 ipv6_setsockopt+0xbd/0x170 net/ipv6/ipv6_sockglue.c:922 udpv6_setsockopt+0x62/0xa0 net/ipv6/udp.c:1445 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3042 __sys_setsockopt+0x1bd/0x390 net/socket.c:1903 __do_sys_setsockopt net/socket.c:1914 [inline] __se_sys_setsockopt net/socket.c:1911 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455979 RSP: 002b:00007f4a4667ec68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f4a4667f6d4 RCX: 0000000000455979 RDX: 0000000000000020 RSI: 0000000000000029 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000020 R09: 0000000000000000 R10: 0000000020f68000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000054e R14: 00000000006faff0 R15: 0000000000000000 openvswitch: netlink: Either Ethernet header or EtherType is required. openvswitch: netlink: Either Ethernet header or EtherType is required. dccp_invalid_packet: P.Data Offset(4) too small IPVS: set_ctl: invalid protocol: 0 172.20.20.170:20001 rr cannot load conntrack support for proto=7 IPVS: set_ctl: invalid protocol: 0 172.20.20.170:20001 rr cannot load conntrack support for proto=7 syz-executor6 (6715) used greatest stack depth: 16536 bytes left IPVS: set_ctl: invalid protocol: 0 0.0.0.0:4096 wlc IPVS: set_ctl: invalid protocol: 0 0.0.0.0:4096 wlc netlink: 8 bytes leftover after parsing attributes in process `syz-executor2'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor2'. bridge0: port 2(bridge_slave_1) entered disabled state kernel msg: ebtables bug: please report to author: Wrong len argument syz-executor6 uses obsolete (PF_INET,SOCK_PACKET) kernel msg: ebtables bug: please report to author: Wrong len argument kernel msg: ebtables bug: please report to author: Wrong len argument netlink: 'syz-executor0': attribute type 1 has an invalid length. netlink: 4 bytes leftover after parsing attributes in process `syz-executor0'. kernel msg: ebtables bug: please report to author: Wrong len argument netlink: 'syz-executor0': attribute type 1 has an invalid length. netlink: 4 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 'syz-executor3': attribute type 1 has an invalid length. netlink: 'syz-executor3': attribute type 1 has an invalid length. netlink: 'syz-executor0': attribute type 41 has an invalid length. netlink: 'syz-executor3': attribute type 1 has an invalid length. kernel msg: ebtables bug: please report to author: Wrong len argument kernel msg: ebtables bug: please report to author: Num_counters wrong kernel msg: ebtables bug: please report to author: entries_size too small netlink: 20 bytes leftover after parsing attributes in process `syz-executor4'. kernel msg: ebtables bug: please report to author: Wrong len argument kernel msg: ebtables bug: please report to author: Num_counters wrong netlink: 20 bytes leftover after parsing attributes in process `syz-executor4'. kernel msg: ebtables bug: please report to author: entries_size too small do_dccp_setsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app kernel msg: ebtables bug: please report to author: entries_size too small do_dccp_setsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app syz-executor1 (7466) used greatest stack depth: 14840 bytes left x_tables: eb_tables: arpreply target: used from hooks OUTPUT, but only usable from PREROUTING x_tables: eb_tables: arpreply target: used from hooks OUTPUT, but only usable from PREROUTING