[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 17.306106] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.734290] random: sshd: uninitialized urandom read (32 bytes read) [ 22.106209] random: sshd: uninitialized urandom read (32 bytes read) [ 22.951363] random: sshd: uninitialized urandom read (32 bytes read) [ 23.105337] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.27' (ECDSA) to the list of known hosts. [ 28.564657] random: sshd: uninitialized urandom read (32 bytes read) RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported [ 28.657669] IPVS: Creating netns size=2536 id=1 Error: argument "bridge0" is wrong: Device does not exist Error: argument "bridge0" is wrong: Device does not exist Error: argument "bond0" is wrong: Device does not exist Error: argument "bond0" is wrong: Device does not exist [ 28.739843] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 28.751222] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready Error: argument "team0" is wrong: Device does not exist Error: argument "team0" is wrong: Device does not exist [ 28.793276] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 28.804542] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 28.846198] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 28.857241] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 28.869274] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready RTNETLINK answers: Operation not supported [ 28.890237] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" RTNETLINK answers: Operation not supported Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "team0" Cannot find device "team0" Cannot find device "team0" Cannot find device "team0" [ 29.377089] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 29.400412] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 29.406569] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 29.414229] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready executing program [ 29.560458] [ 29.562099] ====================================================== [ 29.568392] [ INFO: possible circular locking dependency detected ] [ 29.574769] 4.9.111-g03c70fe #5 Not tainted [ 29.579058] ------------------------------------------------------- [ 29.585431] syz-executor234/3807 is trying to acquire lock: [ 29.591128] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 29.598945] but task is already holding lock: [ 29.603583] (sk_lock-AF_INET){+.+.+.}, at: [] do_ip_setsockopt.isra.13+0x269/0x2b10 [ 29.613377] which lock already depends on the new lock. [ 29.613377] [ 29.620372] [ 29.620372] the existing dependency chain (in reverse order) is: [ 29.628056] -> #1 (sk_lock-AF_INET){+.+.+.}: [ 29.633091] lock_acquire+0x130/0x3e0 [ 29.637386] lock_sock_nested+0xc6/0x120 [ 29.641938] ip_mc_config+0x147/0x1f0 [ 29.646230] inet_rtm_newaddr+0xb1b/0xef0 [ 29.650869] rtnetlink_rcv_msg+0x49c/0x650 [ 29.655602] netlink_rcv_skb+0x145/0x370 [ 29.660157] rtnetlink_rcv+0x2a/0x40 [ 29.664370] netlink_unicast+0x4d8/0x6f0 [ 29.668933] netlink_sendmsg+0x795/0xc30 [ 29.673497] sock_sendmsg+0xcc/0x110 [ 29.677723] ___sys_sendmsg+0x6fc/0x840 [ 29.682187] __sys_sendmsg+0xd9/0x190 [ 29.686479] SyS_sendmsg+0x2d/0x50 [ 29.690512] do_syscall_64+0x1a6/0x490 [ 29.694895] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 29.700494] -> #0 (rtnl_mutex){+.+.+.}: [ 29.705093] __lock_acquire+0x3019/0x4070 [ 29.709733] lock_acquire+0x130/0x3e0 [ 29.714023] mutex_lock_nested+0xc0/0x870 [ 29.718663] rtnl_lock+0x17/0x20 [ 29.722528] mrtsock_destruct+0x3b/0x1e0 [ 29.727089] ip_ra_control+0x2c2/0x420 [ 29.731493] do_ip_setsockopt.isra.13+0x15ff/0x2b10 [ 29.737013] ip_setsockopt+0x3a/0xb0 [ 29.741238] raw_setsockopt+0xb7/0xd0 [ 29.745541] sock_common_setsockopt+0x9a/0xe0 [ 29.750533] SyS_setsockopt+0x166/0x260 [ 29.755005] do_syscall_64+0x1a6/0x490 [ 29.759385] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 29.764985] [ 29.764985] other info that might help us debug this: [ 29.764985] [ 29.773103] Possible unsafe locking scenario: [ 29.773103] [ 29.779134] CPU0 CPU1 [ 29.783769] ---- ---- [ 29.788406] lock(sk_lock-AF_INET); [ 29.792330] lock(rtnl_mutex); [ 29.798337] lock(sk_lock-AF_INET); [ 29.804786] lock(rtnl_mutex); [ 29.808271] [ 29.808271] *** DEADLOCK *** [ 29.808271] [ 29.814300] 1 lock held by syz-executor234/3807: [ 29.819020] #0: (sk_lock-AF_INET){+.+.+.}, at: [] do_ip_setsockopt.isra.13+0x269/0x2b10 [ 29.829359] [ 29.829359] stack backtrace: [ 29.833829] CPU: 1 PID: 3807 Comm: syz-executor234 Not tainted 4.9.111-g03c70fe #5 [ 29.841510] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.850842] ffff8801d96275f8 ffffffff81eb2729 ffffffff8559cef0 ffffffff855e79b0 [ 29.858854] ffffffff8559cef0 ffff8801d95888e8 ffff8801d9588000 ffff8801d9627640 [ 29.866887] ffffffff814263a4 0000000000000001 00000000d9588000 0000000000000001 [ 29.874980] Call Trace: [ 29.877551] [] dump_stack+0xc1/0x128 [ 29.882900] [] print_circular_bug.cold.51+0x1bd/0x27d [ 29.889723] [] __lock_acquire+0x3019/0x4070 [ 29.895670] [] ? debug_check_no_locks_freed+0x210/0x210 [ 29.902657] [] ? add_lock_to_list.isra.27.constprop.41+0x140/0x1c0 [ 29.910610] [] ? __lock_is_held+0xa2/0xf0 [ 29.916391] [] lock_acquire+0x130/0x3e0 [ 29.921997] [] ? rtnl_lock+0x17/0x20 [ 29.927342] [] ? rtnl_lock+0x17/0x20 [ 29.932692] [] mutex_lock_nested+0xc0/0x870 [ 29.938658] [] ? rtnl_lock+0x17/0x20 [ 29.944011] [] ? mutex_trylock+0x3e0/0x3e0 [ 29.949880] [] ? mark_held_locks+0xc7/0x130 [ 29.955837] [] ? __local_bh_enable_ip+0x6a/0xd0 [ 29.962141] [] rtnl_lock+0x17/0x20 [ 29.967313] [] mrtsock_destruct+0x3b/0x1e0 [ 29.973184] [] ? mroute_clean_tables+0x500/0x500 [ 29.979569] [] ip_ra_control+0x2c2/0x420 [ 29.985251] [] do_ip_setsockopt.isra.13+0x15ff/0x2b10 [ 29.992060] [] ? ip_ra_control+0x420/0x420 [ 29.997934] [] ? get_empty_filp+0x8f/0x380 [ 30.003795] [] ? alloc_file+0x20/0x350 [ 30.009316] [] ? sock_alloc_file+0x151/0x330 [ 30.015350] [] ? sock_map_fd+0x34/0x70 [ 30.020856] [] ? SyS_socket+0x10f/0x1b0 [ 30.026452] [] ? do_syscall_64+0x1a6/0x490 [ 30.032308] [] ? entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 30.039389] [] ? debug_check_no_locks_freed+0x210/0x210 [ 30.046382] [] ? debug_check_no_locks_freed+0x210/0x210 [ 30.053379] [] ? check_preemption_disabled+0x3b/0x170 [ 30.060190] [] ? sock_has_perm+0x1c2/0x3e0 [ 30.066045] [] ? sock_has_perm+0x292/0x3e0 [ 30.071903] [] ? sock_has_perm+0x9f/0x3e0 [ 30.077686] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 30.084765] [] ? selinux_netlbl_socket_setsockopt+0x8c/0x340 [ 30.092184] [] ? selinux_netlbl_sock_rcv_skb+0x480/0x480 [ 30.099256] [] ip_setsockopt+0x3a/0xb0 [ 30.105121] [] raw_setsockopt+0xb7/0xd0 [ 30.110732] [] sock_common_setsockopt+0x9a/0xe0 [ 30.117044] [] SyS_setsockopt+0x166/0x260 [ 30.122828] [] ? SyS_recv+0x40/0x40 [ 30.128075] [] ? move_addr_to_kernel+0x50/0x50 [ 30.134289] [] ? do_syscall_64+0x48/0x490 [ 30.140056] [] ? SyS_recv+0x40/0x40 [ 30.145311] [] do_syscall_64+0x1a6/0x490 [ 30.150993] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb