[ 19.739936] random: sshd: uninitialized urandom read (32 bytes read, 31 bits of entropy available) [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [ 20.227179] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [ 20.504761] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.368211] random: sshd: uninitialized urandom read (32 bytes read, 104 bits of entropy available) [ 21.518616] random: sshd: uninitialized urandom read (32 bytes read, 107 bits of entropy available) Warning: Permanently added '10.128.15.208' (ECDSA) to the list of known hosts. [ 26.852692] random: sshd: uninitialized urandom read (32 bytes read, 113 bits of entropy available) 2018/02/20 02:35:12 parsed 1 programs 2018/02/20 02:35:12 executed programs: 0 [ 27.197991] IPVS: Creating netns size=2552 id=1 [ 27.323442] ip (3821) used greatest stack depth: 25016 bytes left [ 27.902128] BUG: using __this_cpu_add() in preemptible [00000000] code: syz-executor0/4000 [ 27.910612] caller is __this_cpu_preempt_check+0x1c/0x20 [ 27.916044] CPU: 1 PID: 4000 Comm: syz-executor0 Not tainted 4.4.115-g55a366596 #14 [ 27.923810] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.933135] 0000000000000000 cd4af439e4eb773b ffff8801d84d7740 ffffffff81d03d8d [ 27.941118] 0000000000000001 ffffffff839fe4a0 ffffffff83cef860 ffff8801d9544800 [ 27.949125] 0000000000000003 ffff8801d84d7780 ffffffff81d63cd4 ffffffff81237470 [ 27.957107] Call Trace: [ 27.959685] [] dump_stack+0xc1/0x124 [ 27.965033] [] check_preemption_disabled+0x1d4/0x200 [ 27.971760] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.978753] [] __this_cpu_preempt_check+0x1c/0x20 [ 27.985217] [] tcp_try_rmem_schedule+0xf2/0x1180 [ 27.991591] [] ? skb_put+0x149/0x1c0 [ 27.996921] [] tcp_send_rcvq+0x1ba/0x450 [ 28.002603] [] ? tcp_rcv_established+0x2230/0x2230 [ 28.009151] [] ? tcp_sendmsg+0xb3/0x2b10 [ 28.014833] [] ? lock_sock_nested+0xa2/0x120 [ 28.020862] [] ? lock_sock_nested+0x90/0x120 [ 28.026890] [] ? trace_hardirqs_on+0xd/0x10 [ 28.032840] [] ? __local_bh_enable_ip+0x6a/0xd0 [ 28.039129] [] tcp_sendmsg+0x1e8f/0x2b10 [ 28.044817] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.051807] [] ? sock_has_perm+0x1c1/0x400 [ 28.057662] [] ? tcp_sendpage+0x1830/0x1830 [ 28.063602] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 28.070673] [] ? inet_sendmsg+0x73/0x4c0 [ 28.076364] [] ? inet_sendmsg+0x201/0x4c0 [ 28.082132] [] inet_sendmsg+0x2bc/0x4c0 [ 28.087724] [] ? inet_sendmsg+0x73/0x4c0 [ 28.093404] [] ? inet_recvmsg+0x4c0/0x4c0 [ 28.099174] [] sock_sendmsg+0xca/0x110 [ 28.104682] [] ___sys_sendmsg+0x6c1/0x7c0 [ 28.110450] [] ? copy_msghdr_from_user+0x550/0x550 [ 28.117010] [] ? do_futex+0x3f4/0x15d0 [ 28.122519] [] ? filemap_map_pages+0x508/0x9d0 [ 28.128719] [] ? filemap_map_pages+0x10a/0x9d0 [ 28.134920] [] ? exit_robust_list+0x240/0x240 [ 28.141047] [] ? grab_cache_page_write_begin+0x90/0x90 [ 28.147948] [] ? handle_mm_fault+0x192d/0x3190 [ 28.154154] [] ? _raw_spin_unlock+0x2c/0x50 [ 28.160096] [] ? __fget_light+0xa1/0x1e0 [ 28.165775] [] ? __fdget+0x18/0x20 [ 28.170939] [] __sys_sendmsg+0xd3/0x190 [ 28.176535] [] ? SyS_shutdown+0x1b0/0x1b0 [ 28.182302] [] ? SyS_futex+0x210/0x2c0 [ 28.187814] [] ? move_addr_to_kernel+0x50/0x50 [ 28.194017] [] SyS_sendmsg+0x2d/0x50 [ 28.199362] [] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 28.206152] BUG: using __this_cpu_add() in preemptible [00000000] code: syz-executor0/4000 [ 28.214699] caller is __this_cpu_preempt_check+0x1c/0x20 [ 28.220125] CPU: 1 PID: 4000 Comm: syz-executor0 Not tainted 4.4.115-g55a366596 #14 [ 28.227885] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.237209] 0000000000000000 cd4af439e4eb773b ffff8801d84d7740 ffffffff81d03d8d [ 28.245189] 0000000000000001 ffffffff839fe4a0 ffffffff83cef860 ffff8801d9544800 [ 28.253176] 0000000000000003 ffff8801d84d7780 ffffffff81d63cd4 ffffffff8313163a [ 28.261155] Call Trace: [ 28.263716] [] dump_stack+0xc1/0x124 [ 28.269051] [] check_preemption_disabled+0x1d4/0x200 [ 28.275777] [] ? tcp_prune_ofo_queue+0x30a/0x420 [ 28.282155] [] __this_cpu_preempt_check+0x1c/0x20 [ 28.288619] [] tcp_try_rmem_schedule+0xe33/0x1180 [ 28.295082] [] tcp_send_rcvq+0x1ba/0x450 [ 28.300763] [] ? tcp_rcv_established+0x2230/0x2230 [ 28.307313] [] ? tcp_sendmsg+0xb3/0x2b10 [ 28.312998] [] ? lock_sock_nested+0xa2/0x120 [ 28.319026] [] ? lock_sock_nested+0x90/0x120 [ 28.325054] [] ? trace_hardirqs_on+0xd/0x10 [ 28.330993] [] ? __local_bh_enable_ip+0x6a/0xd0 [ 28.337281] [] tcp_sendmsg+0x1e8f/0x2b10 [ 28.342961] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.349945] [] ? sock_has_perm+0x1c1/0x400 [ 28.355800] [] ? tcp_sendpage+0x1830/0x1830 [ 28.361741] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 28.368818] [] ? inet_sendmsg+0x73/0x4c0 [ 28.374521] [] ? inet_sendmsg+0x201/0x4c0 [ 28.380305] [] inet_sendmsg+0x2bc/0x4c0 [ 28.385902] [] ? inet_sendmsg+0x73/0x4c0 [ 28.391588] [] ? inet_recvmsg+0x4c0/0x4c0 [ 28.397362] [] sock_sendmsg+0xca/0x110 [ 28.402873] [] ___sys_sendmsg+0x6c1/0x7c0 [ 28.408638] [] ? copy_msghdr_from_user+0x550/0x550 [ 28.415190] [] ? do_futex+0x3f4/0x15d0 [ 28.420698] [] ? filemap_map_pages+0x508/0x9d0 [ 28.426898] [] ? filemap_map_pages+0x10a/0x9d0 [ 28.433100] [] ? exit_robust_list+0x240/0x240 [ 28.439217] [] ? grab_cache_page_write_begin+0x90/0x90 [ 28.446114] [] ? handle_mm_fault+0x192d/0x3190 [ 28.452316] [