[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 21.302759] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 25.811850] random: sshd: uninitialized urandom read (32 bytes read, 40 bits of entropy available) [ 26.393503] random: sshd: uninitialized urandom read (32 bytes read, 40 bits of entropy available) [ 27.365982] random: sshd: uninitialized urandom read (32 bytes read, 114 bits of entropy available) [ 27.552580] random: sshd: uninitialized urandom read (32 bytes read, 118 bits of entropy available) Warning: Permanently added '10.128.10.11' (ECDSA) to the list of known hosts. [ 33.038525] random: sshd: uninitialized urandom read (32 bytes read, 126 bits of entropy available) executing program [ 33.125317] kasan: CONFIG_KASAN_INLINE enabled [ 33.129734] kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN [ 33.142572] Dumping ftrace buffer: [ 33.146079] (ftrace buffer empty) [ 33.149757] Modules linked in: [ 33.153035] CPU: 0 PID: 3769 Comm: syzkaller204201 Not tainted 4.4.125-g38f41ec #63 [ 33.160792] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.170113] task: ffff8801c8713000 task.stack: ffff8801c7a78000 [ 33.176136] RIP: 0010:[] [] __free_pages+0x21/0x90 [ 33.184389] RSP: 0018:ffff8801c7a7f9e8 EFLAGS: 00010a07 [ 33.189805] RAX: dffffc0000000000 RBX: dead4ead00000000 RCX: ffffffff825bb1fb [ 33.197041] RDX: 1bd5a9d5a0000003 RSI: 0000000000000001 RDI: dead4ead0000001c [ 33.204281] RBP: ffff8801c7a7f9f8 R08: 0000000000000001 R09: 0000000000000000 [ 33.211516] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004 [ 33.218773] R13: 0000000000000020 R14: ffff8800ac804200 R15: dffffc0000000000 [ 33.226013] FS: 0000000001cf9880(0063) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 33.234205] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 33.240052] CR2: 000000000043e740 CR3: 00000001d1f08000 CR4: 0000000000160670 [ 33.247291] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 33.254531] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 33.261767] Stack: [ 33.263881] 0000000000000000 ffff8800ac804358 ffff8801c7a7fa58 ffffffff825bb221 [ 33.271843] ffff8800ac804370 ffffed001590086b ffffed001590086e ffff8800ac804368 [ 33.279800] dead4ead00000000 ffff8800ac804340 0000000000000000 0000000000000000 [ 33.287757] Call Trace: [ 33.290318] [] sg_remove_scat.isra.17+0x1c1/0x2d0 [ 33.296810] [] sg_finish_rem_req+0x2a6/0x320 [ 33.302837] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 33.309644] [] sg_new_read+0x3c/0x420 [ 33.315061] [] ? sg_get_rq_mark+0x142/0x190 [ 33.320996] [] sg_read+0x8cf/0x14d0 [ 33.326241] [] ? __check_object_size+0x154/0x35b [ 33.332613] [] ? sg_proc_seq_show_debug+0xda0/0xda0 [ 33.339243] [] ? fsnotify+0xee0/0xee0 [ 33.344663] [] ? avc_policy_seqno+0x9/0x20 [ 33.350515] [] do_loop_readv_writev+0x141/0x1e0 [ 33.356802] [] ? security_file_permission+0x89/0x1e0 [ 33.363530] [] ? sg_proc_seq_show_debug+0xda0/0xda0 [ 33.370162] [] ? sg_proc_seq_show_debug+0xda0/0xda0 [ 33.376798] [] do_readv_writev+0x5dd/0x6e0 [ 33.382646] [] ? vfs_write+0x530/0x530 [ 33.388148] [] ? sg_ioctl+0x2a00/0x2a00 [ 33.393742] [] ? __vfs_write+0x10b/0x450 [ 33.399418] [] ? quarantine_put+0xab/0x180 [ 33.405269] [] ? putname+0xee/0x130 [ 33.410513] [] ? fsnotify+0xee0/0xee0 [ 33.415929] [] ? rw_verify_area+0x100/0x2f0 [ 33.421866] [] vfs_readv+0x78/0xb0 [ 33.427022] [] SyS_readv+0xd9/0x240 [ 33.432268] [] ? rw_copy_check_uvector+0x2b0/0x2b0 [ 33.438814] [] ? lockdep_sys_exit_thunk+0x12/0x14 [ 33.445276] [] entry_SYSCALL_64_fastpath+0x22/0x9e [ 33.451818] Code: c6 a0 0c 00 e9 78 fd ff ff 90 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 48 89 fb 48 83 c7 1c 48 89 fa 48 83 ec 08 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 49 [ 33.478328] RIP [] __free_pages+0x21/0x90 [ 33.484213] RSP [ 33.488109] ---[ end trace 9e6d71aab632ea3d ]--- [ 33.492858] Kernel panic - not syncing: Fatal exception [ 33.498664] Dumping ftrace buffer: [ 33.502178] (ftrace buffer empty) [ 33.505855] Kernel Offset: disabled [ 33.509447] Rebooting in 86400 seconds..