[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 18.548408] random: sshd: uninitialized urandom read (32 bytes read, 31 bits of entropy available) [?25l[?1c7[ ok 8[?25h[?0c. [ 18.702551] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [ 18.890531] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.116372] random: sshd: uninitialized urandom read (32 bytes read, 105 bits of entropy available) [ 20.284142] random: sshd: uninitialized urandom read (32 bytes read, 109 bits of entropy available) Warning: Permanently added '10.128.15.208' (ECDSA) to the list of known hosts. [ 25.628384] random: sshd: uninitialized urandom read (32 bytes read, 114 bits of entropy available) 2018/02/20 07:46:46 parsed 1 programs 2018/02/20 07:46:46 executed programs: 0 [ 25.966055] IPVS: Creating netns size=2552 id=1 [ 26.625078] BUG: using __this_cpu_add() in preemptible [00000000] code: syz-executor0/3998 [ 26.633516] caller is __this_cpu_preempt_check+0x1c/0x20 [ 26.638943] CPU: 0 PID: 3998 Comm: syz-executor0 Not tainted 4.4.115-g55a366596 #14 [ 26.646704] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.656026] 0000000000000000 39f2478c2b18d88d ffff8801d845f6b0 ffffffff81d03d8d [ 26.663993] 0000000000000000 ffffffff839fe4a0 ffffffff83cef860 ffff8800ba3c0000 [ 26.671957] 0000000000000003 ffff8801d845f6f0 ffffffff81d63cd4 ffffffff81237470 [ 26.679930] Call Trace: [ 26.682488] [] dump_stack+0xc1/0x124 [ 26.687823] [] check_preemption_disabled+0x1d4/0x200 [ 26.694548] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 26.701534] [] __this_cpu_preempt_check+0x1c/0x20 [ 26.707994] [] tcp_try_rmem_schedule+0xf2/0x1180 [ 26.714367] [] ? skb_put+0x149/0x1c0 [ 26.719697] [] tcp_send_rcvq+0x1ba/0x450 [ 26.725374] [] ? tcp_rcv_established+0x2230/0x2230 [ 26.731919] [] ? tcp_sendmsg+0xb3/0x2b10 [ 26.737598] [] ? lock_sock_nested+0xa2/0x120 [ 26.743622] [] ? lock_sock_nested+0x90/0x120 [ 26.749647] [] ? trace_hardirqs_on+0xd/0x10 [ 26.755585] [] ? __local_bh_enable_ip+0x6a/0xd0 [ 26.761871] [] tcp_sendmsg+0x1e8f/0x2b10 [ 26.767550] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 26.774533] [] ? sock_has_perm+0x1c1/0x400 [ 26.780392] [] ? tcp_sendpage+0x1830/0x1830 [ 26.786332] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 26.793399] [] ? inet_sendmsg+0x73/0x4c0 [ 26.799076] [] ? inet_sendmsg+0x201/0x4c0 [ 26.804840] [] inet_sendmsg+0x2bc/0x4c0 [ 26.810429] [] ? inet_sendmsg+0x73/0x4c0 [ 26.816108] [] ? inet_recvmsg+0x4c0/0x4c0 [ 26.821875] [] sock_sendmsg+0xca/0x110 [ 26.827380] [] sock_write_iter+0x226/0x3b0 [ 26.833230] [] ? sock_sendmsg+0x110/0x110 [ 26.839390] [] ? rw_copy_check_uvector+0x21e/0x2b0 [ 26.845937] [] do_iter_readv_writev+0x138/0x1e0 [ 26.852222] [] ? sock_sendmsg+0x110/0x110 [ 26.857991] [] ? vfs_iter_read+0x270/0x270 [ 26.863856] [] ? rw_verify_area+0x100/0x2f0 [ 26.869797] [] ? sock_sendmsg+0x110/0x110 [ 26.875572] [] do_readv_writev+0x2d2/0x6e0 [ 26.881424] [] ? vfs_write+0x530/0x530 [ 26.886928] [] ? _raw_spin_unlock+0x2c/0x50 [ 26.892865] [] ? do_huge_pmd_anonymous_page+0x3dd/0xa10 [ 26.899844] [] ? handle_mm_fault+0x3f2/0x3190 [ 26.905955] [] vfs_writev+0x7b/0xb0 [ 26.911198] [] SyS_writev+0xd9/0x240 [ 26.916527] [] ? SyS_readv+0x240/0x240 [ 26.922041] [] ? lockdep_sys_exit_thunk+0x12/0x14 [ 26.928501] [] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 26.935409] BUG: using __this_cpu_add() in preemptible [00000000] code: syz-executor0/3998 [ 26.943815] caller is __this_cpu_preempt_check+0x1c/0x20 [ 26.949245] CPU: 0 PID: 3998 Comm: syz-executor0 Not tainted 4.4.115-g55a366596 #14 [ 26.957006] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.966326] 0000000000000000 39f2478c2b18d88d ffff8801d845f6b0 ffffffff81d03d8d [ 26.974288] 0000000000000000 ffffffff839fe4a0 ffffffff83cef860 ffff8800ba3c0000 [ 26.982260] 0000000000000003 ffff8801d845f6f0 ffffffff81d63cd4 ffffffff8313163a [ 26.990226] Call Trace: [ 26.992784] [] dump_stack+0xc1/0x124 [ 26.998115] [] check_preemption_disabled+0x1d4/0x200 [ 27.004837] [] ? tcp_prune_ofo_queue+0x30a/0x420 [ 27.011208] [] __this_cpu_preempt_check+0x1c/0x20 [ 27.017666] [] tcp_try_rmem_schedule+0xe33/0x1180 [ 27.024126] [] tcp_send_rcvq+0x1ba/0x450 [ 27.029805] [] ? tcp_rcv_established+0x2230/0x2230 [ 27.036350] [] ? tcp_sendmsg+0xb3/0x2b10 [ 27.042032] [] ? lock_sock_nested+0xa2/0x120 [ 27.048064] [] ? lock_sock_nested+0x90/0x120 [ 27.054091] [] ? trace_hardirqs_on+0xd/0x10 [ 27.060029] [] ? __local_bh_enable_ip+0x6a/0xd0 [ 27.066313] [] tcp_sendmsg+0x1e8f/0x2b10 [ 27.071993] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.078973] [] ? sock_has_perm+0x1c1/0x400 [ 27.084825] [] ? tcp_sendpage+0x1830/0x1830 [ 27.090764] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 27.097830] [] ? inet_sendmsg+0x73/0x4c0 [ 27.103506] [] ? inet_sendmsg+0x201/0x4c0 [ 27.109269] [] inet_sendmsg+0x2bc/0x4c0 [ 27.114860] [] ? inet_sendmsg+0x73/0x4c0 [ 27.120543] [] ? inet_recvmsg+0x4c0/0x4c0 [ 27.126316] [] sock_sendmsg+0xca/0x110 [ 27.131825] [] sock_write_iter+0x226/0x3b0 [ 27.137676] [] ? sock_sendmsg+0x110/0x110 [ 27.143440] [] ? rw_copy_check_uvector+0x21e/0x2b0 [ 27.149988] [] do_iter_readv_writev+0x138/0x1e0 [ 27.156273] [] ? sock_sendmsg+0x110/0x110 [ 27.162036] [] ? vfs_iter_read+0x270/0x270 [ 27.167887] [] ? rw_verify_area+0x100/0x2f0 [ 27.173823] [] ? sock_sendmsg+0x110/0x110 [ 27.179588] [] do_readv_writev+0x2d2/0x6e0 [ 27.185439] [] ? vfs_write+0x530/0x530 [ 27.190943] [] ? _raw_spin_unlock+0x2c/0x50 [ 27.196885] [] ? do_huge_pmd_anonymous_page+0x3dd/0xa10 [ 27.203864] [] ? handle_mm_fault+0x3f2/0x3190 [ 27.209975] [] vfs_writev+0x7b/0xb0 [ 27.215215] [] SyS_writev+0xd9/0x240 [ 27.220543] [] ? SyS_readv+0x240/0x240 [ 27.226047] [