[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.287095] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.438445] random: sshd: uninitialized urandom read (32 bytes read) [ 22.700515] random: sshd: uninitialized urandom read (32 bytes read) [ 23.522859] random: sshd: uninitialized urandom read (32 bytes read) [ 23.681916] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.59' (ECDSA) to the list of known hosts. [ 29.189903] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 29.294660] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 [ 29.302784] PGD 1ac704067 P4D 1ac704067 PUD 1ac791067 PMD 0 [ 29.309207] Oops: 0010 [#1] SMP KASAN [ 29.313000] CPU: 1 PID: 4531 Comm: syz-executor111 Not tainted 4.17.0+ #84 [ 29.320003] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.329355] RIP: 0010: (null) [ 29.333221] Code: Bad RIP value. [ 29.336614] RSP: 0018:ffff8801ac77f3a0 EFLAGS: 00010246 [ 29.341979] RAX: 0000000000000000 RBX: ffff8801d95de800 RCX: 1ffffffff10ea9fd [ 29.349252] RDX: ffff8801ac77fc00 RSI: ffff8801bc903940 RDI: ffff8801d90f3540 [ 29.356511] RBP: ffff8801ac77f510 R08: ffff8801d9010af8 R09: 0000000000000006 [ 29.363777] R10: ffff8801d90102c0 R11: 0000000000000000 R12: 1ffff100358efe79 [ 29.371043] R13: ffff8801ac77fc00 R14: ffff8801d95de812 R15: ffff8801d95dec58 [ 29.378299] FS: 0000000001dd6880(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 [ 29.386502] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 29.392364] CR2: ffffffffffffffd6 CR3: 00000001d90e3000 CR4: 00000000001406e0 [ 29.399633] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 29.406987] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 29.414247] Call Trace: [ 29.416826] ? smc_poll+0x211/0xdd0 [ 29.420529] ? __smc_connect+0xa90/0xa90 [ 29.424570] ? save_stack+0x43/0xd0 [ 29.428181] ? kasan_kmalloc+0xc4/0xe0 [ 29.432052] ? kasan_slab_alloc+0x12/0x20 [ 29.436183] ? kmem_cache_alloc+0x12e/0x760 [ 29.440484] ? ep_insert+0x270/0x1c00 [ 29.444269] ? __x64_sys_epoll_ctl+0xef1/0x10f0 [ 29.448922] ? do_syscall_64+0x1b1/0x800 [ 29.452975] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 29.458326] ? graph_lock+0x170/0x170 [ 29.462112] ? debug_check_no_locks_freed+0x310/0x310 [ 29.467293] ? find_held_lock+0x36/0x1c0 [ 29.471340] ? print_usage_bug+0xc0/0xc0 [ 29.475399] sock_poll+0x1d1/0x710 [ 29.478930] ? __smc_connect+0xa90/0xa90 [ 29.482985] ? sock_get_poll_head+0x460/0x460 [ 29.487553] ? sock_get_poll_head+0x460/0x460 [ 29.492038] vfs_poll+0x77/0x2a0 [ 29.495390] ep_item_poll.isra.15+0x2c1/0x390 [ 29.499870] ? rcu_read_lock_sched_held+0x108/0x120 [ 29.504868] ? ep_eventpoll_poll+0x1f0/0x1f0 [ 29.509269] ? ep_insert+0x270/0x1c00 [ 29.513053] ep_insert+0x6b8/0x1c00 [ 29.516678] ? pudp_huge_clear_flush+0x230/0x230 [ 29.521425] ? ep_send_events_proc+0xee0/0xee0 [ 29.525993] ? lock_release+0xa10/0xa10 [ 29.529953] ? check_same_owner+0x320/0x320 [ 29.534264] ? rcu_note_context_switch+0x710/0x710 [ 29.539183] ? __might_sleep+0x95/0x190 [ 29.543154] ? kasan_check_write+0x14/0x20 [ 29.547377] ? __mutex_lock+0x7d9/0x17f0 [ 29.551430] ? __x64_sys_epoll_ctl+0x518/0x10f0 [ 29.556104] ? find_held_lock+0x36/0x1c0 [ 29.560164] ? mutex_trylock+0x2a0/0x2a0 [ 29.564220] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.569236] ? graph_lock+0x170/0x170 [ 29.573039] ? lockdep_init_map+0x9/0x10 [ 29.577103] ? debug_mutex_init+0x2d/0x60 [ 29.581237] ? pud_val+0x80/0xf0 [ 29.584586] ? pmd_val+0xf0/0xf0 [ 29.587937] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.593470] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.598993] ? __handle_mm_fault+0x93a/0x4390 [ 29.603507] ? find_held_lock+0x36/0x1c0 [ 29.607678] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.613205] ? __fget_light+0x2ef/0x430 [ 29.617268] ? fget_raw+0x20/0x20 [ 29.620722] ? find_held_lock+0x36/0x1c0 [ 29.624774] ? __might_sleep+0x95/0x190 [ 29.628814] ? clear_tfile_check_list+0x380/0x380 [ 29.633643] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 29.638882] __x64_sys_epoll_ctl+0xef1/0x10f0 [ 29.643372] ? __ia32_sys_epoll_create+0x70/0x70 [ 29.648112] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.653656] ? __do_page_fault+0x441/0xe40 [ 29.658065] ? mm_fault_error+0x380/0x380 [ 29.662211] ? __ia32_sys_fallocate+0xf0/0xf0 [ 29.666696] ? do_syscall_64+0x92/0x800 [ 29.670672] do_syscall_64+0x1b1/0x800 [ 29.674562] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 29.679397] ? syscall_return_slowpath+0x5c0/0x5c0 [ 29.684319] ? syscall_return_slowpath+0x30f/0x5c0 [ 29.689232] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.694784] ? retint_user+0x18/0x18 [ 29.698488] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.703318] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 29.708505] RIP: 0033:0x43fce9 [ 29.711697] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 6b 45 00 00 c3 66 2e 0f 1f 84 00 00 00 00 [ 29.730840] RSP: 002b:00007ffec5ef3ea8 EFLAGS: 00000217 ORIG_RAX: 00000000000000e9 [ 29.738545] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fce9 [ 29.745886] RDX: 0000000000000003 RSI: 0000000000000001 RDI: 0000000000000004 [ 29.753148] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 29.760402] R10: 0000000020c7f000 R11: 0000000000000217 R12: 0000000000401610 [ 29.767656] R13: 00000000004016a0 R14: 0000000000000000 R15: 0000000000000000 [ 29.774917] Modules linked in: [ 29.778092] Dumping ftrace buffer: [ 29.781616] (ftrace buffer empty) [ 29.785313] CR2: 0000000000000000 [ 29.788816] ---[ end trace 78c719141a3f2e13 ]--- [ 29.793610] RIP: 0010: (null) [ 29.797511] Code: Bad RIP value. [ 29.800897] RSP: 0018:ffff8801ac77f3a0 EFLAGS: 00010246 [ 29.806264] RAX: 0000000000000000 RBX: ffff8801d95de800 RCX: 1ffffffff10ea9fd [ 29.813539] RDX: ffff8801ac77fc00 RSI: ffff8801bc903940 RDI: ffff8801d90f3540 [ 29.821089] RBP: ffff8801ac77f510 R08: ffff8801d9010af8 R09: 0000000000000006 [ 29.828376] R10: ffff8801d90102c0 R11: 0000000000000000 R12: 1ffff100358efe79 [ 29.835667] R13: ffff8801ac77fc00 R14: ffff8801d95de812 R15: ffff8801d95dec58 [ 29.842976] FS: 0000000001dd6880(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 [ 29.851243] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 29.857131] CR2: ffffffffffffffd6 CR3: 00000001d90e3000 CR4: 00000000001406e0 [ 29.864416] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 29.871697] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 29.878982] Kernel panic - not syncing: Fatal exception [ 29.884941] Dumping ftrace buffer: [ 29.888474] (ftrace buffer empty) [ 29.892169] Kernel Offset: disabled [ 29.895776] Rebooting in 86400 seconds..