[....] Starting OpenBSD Secure Shell server: sshd[ 19.839482] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 23.267108] random: sshd: uninitialized urandom read (32 bytes read) [ 23.660261] sshd (4527) used greatest stack depth: 17032 bytes left [ 23.677047] random: sshd: uninitialized urandom read (32 bytes read) [ 24.467336] random: sshd: uninitialized urandom read (32 bytes read) [ 24.625458] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.19' (ECDSA) to the list of known hosts. [ 30.189424] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 30.278498] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 [ 30.286546] PGD 1c6446067 P4D 1c6446067 PUD 1ac70a067 PMD 0 [ 30.292342] Oops: 0010 [#1] SMP KASAN [ 30.296137] CPU: 0 PID: 4544 Comm: syz-executor862 Not tainted 4.17.0+ #84 [ 30.303126] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.312459] RIP: 0010: (null) [ 30.316333] Code: Bad RIP value. [ 30.319692] RSP: 0018:ffff8801ac2bf590 EFLAGS: 00010246 [ 30.325036] RAX: 0000000000000000 RBX: ffff8801adb94800 RCX: 1ffffffff10eeea9 [ 30.332286] RDX: ffff8801ac2bfab0 RSI: ffff8801a74fc000 RDI: ffff8801ad225d40 [ 30.339540] RBP: ffff8801ac2bf700 R08: 0000000000000001 R09: 0000000000000000 [ 30.346793] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff10035857eb7 [ 30.354043] R13: ffff8801ac2bfab0 R14: ffff8801adb94812 R15: ffff8801adb94c58 [ 30.361294] FS: 0000000001b25880(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 [ 30.369497] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 30.375356] CR2: ffffffffffffffd6 CR3: 00000001ad55a000 CR4: 00000000001406f0 [ 30.382608] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.389861] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.397109] Call Trace: [ 30.399684] ? smc_poll+0x211/0xdd0 [ 30.403294] ? __mem_cgroup_threshold+0x720/0x720 [ 30.408123] ? __smc_connect+0xa90/0xa90 [ 30.412167] ? kvm_clock_read+0x25/0x30 [ 30.416120] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.421636] ? ktime_get_ts64+0x39d/0x510 [ 30.425764] ? do_gettimeofday+0x170/0x170 [ 30.429980] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.435503] ? __fget_light+0x2ef/0x430 [ 30.439458] sock_poll+0x1d1/0x710 [ 30.442988] ? __smc_connect+0xa90/0xa90 [ 30.447050] ? sock_get_poll_head+0x460/0x460 [ 30.451526] ? sock_get_poll_head+0x460/0x460 [ 30.456002] vfs_poll+0x77/0x2a0 [ 30.459360] do_sys_poll+0x6fd/0x1100 [ 30.463153] ? compat_core_sys_select+0xae0/0xae0 [ 30.467977] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 30.472972] ? graph_lock+0x170/0x170 [ 30.476749] ? graph_lock+0x170/0x170 [ 30.480530] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.486049] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.491565] ? __handle_mm_fault+0x93a/0x4390 [ 30.496046] ? find_held_lock+0x36/0x1c0 [ 30.500089] ? poll_initwait+0x180/0x180 [ 30.504134] ? pvclock_read_flags+0x160/0x160 [ 30.508610] ? ktime_get_ts64+0x405/0x510 [ 30.512737] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 30.517734] ? timespec64_add_safe+0x1f4/0x2d0 [ 30.522298] ? nsec_to_clock_t+0x30/0x30 [ 30.526339] ? do_gettimeofday+0x170/0x170 [ 30.530559] ? poll_select_set_timeout+0x14f/0x220 [ 30.535487] ? do_restart_poll+0x2d0/0x2d0 [ 30.539707] __x64_sys_poll+0x189/0x510 [ 30.543667] ? __ia32_sys_pselect6+0x270/0x270 [ 30.548229] ? do_syscall_64+0x92/0x800 [ 30.552185] do_syscall_64+0x1b1/0x800 [ 30.556066] ? syscall_return_slowpath+0x5c0/0x5c0 [ 30.560975] ? syscall_return_slowpath+0x30f/0x5c0 [ 30.565895] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.571411] ? retint_user+0x18/0x18 [ 30.575105] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.579929] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.585098] RIP: 0033:0x43fd49 [ 30.588262] 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 [ 30.607377] RSP: 002b:00007ffd3bc2fa88 EFLAGS: 00000213 ORIG_RAX: 0000000000000007 [ 30.615080] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd49 [ 30.622328] RDX: 0000000000000004 RSI: 0000000000000005 RDI: 0000000020000000 [ 30.629575] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 30.636833] R10: 00000000004002c8 R11: 0000000000000213 R12: 0000000000401670 [ 30.644094] R13: 0000000000401700 R14: 0000000000000000 R15: 0000000000000000 [ 30.651344] Modules linked in: [ 30.654535] Dumping ftrace buffer: [ 30.658056] (ftrace buffer empty) [ 30.661756] CR2: 0000000000000000 [ 30.665238] ---[ end trace 8f293e2f1f5b9658 ]--- [ 30.670028] RIP: 0010: (null) [ 30.673933] Code: Bad RIP value. [ 30.677325] RSP: 0018:ffff8801ac2bf590 EFLAGS: 00010246 [ 30.682701] RAX: 0000000000000000 RBX: ffff8801adb94800 RCX: 1ffffffff10eeea9 [ 30.689973] RDX: ffff8801ac2bfab0 RSI: ffff8801a74fc000 RDI: ffff8801ad225d40 [ 30.697243] RBP: ffff8801ac2bf700 R08: 0000000000000001 R09: 0000000000000000 [ 30.704517] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff10035857eb7 [ 30.711796] R13: ffff8801ac2bfab0 R14: ffff8801adb94812 R15: ffff8801adb94c58 [ 30.719079] FS: 0000000001b25880(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 [ 30.727319] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 30.733203] CR2: ffffffffffffffd6 CR3: 00000001ad55a000 CR4: 00000000001406f0 [ 30.740482] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.747774] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.755081] Kernel panic - not syncing: Fatal exception [ 30.760899] Dumping ftrace buffer: [ 30.764424] (ftrace buffer empty) [ 30.768112] Kernel Offset: disabled [ 30.771717] Rebooting in 86400 seconds..