[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 26.322189] random: sshd: uninitialized urandom read (32 bytes read) [ 26.829450] audit: type=1400 audit(1570159569.142:6): avc: denied { map } for pid=1767 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [ 26.866329] random: sshd: uninitialized urandom read (32 bytes read) [ 27.371554] random: sshd: uninitialized urandom read (32 bytes read) [ 27.526978] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.1.26' (ECDSA) to the list of known hosts. [ 32.985299] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 33.082580] audit: type=1400 audit(1570159575.402:7): avc: denied { map } for pid=1785 comm="syz-executor685" path="/root/syz-executor685930511" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 33.094329] kasan: CONFIG_KASAN_INLINE enabled [ 33.113966] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 33.121615] general protection fault: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 33.128366] Modules linked in: [ 33.131545] CPU: 0 PID: 1785 Comm: syz-executor685 Not tainted 4.14.146+ #0 [ 33.138624] task: (ptrval) task.stack: (ptrval) [ 33.144667] RIP: 0010:__blockdev_direct_IO+0x1dcf/0xe24e [ 33.150113] RSP: 0018:ffff8881cffaf330 EFLAGS: 00010202 [ 33.155456] RAX: dffffc0000000000 RBX: ffffea00073e7a1c RCX: ffffffffb4a38603 [ 33.162705] RDX: 0000000000000004 RSI: 0000000000000004 RDI: 0000000000000020 [ 33.169955] RBP: ffff8881cffaf668 R08: 0000000000000000 R09: fffff94000e7cf44 [ 33.177204] R10: fffff94000e7cf43 R11: ffffea00073e7a1f R12: ffffea00073e7a00 [ 33.184455] R13: ffffea00073e7a00 R14: 0000000000000000 R15: ffff8881cff24000 [ 33.191707] FS: 0000555556ba7880(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000 [ 33.199912] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 33.205772] CR2: 0000000020011000 CR3: 00000001cfd72006 CR4: 00000000001606b0 [ 33.213031] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 33.220288] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 33.227534] Call Trace: [ 33.230115] ? sb_init_dio_done_wq+0x90/0x90 [ 33.234505] ? __bfs+0x25/0x540 [ 33.237781] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 33.243385] ? lock_downgrade+0x5d0/0x5d0 [ 33.247513] ext4_direct_IO+0xa4f/0x2820 [ 33.251556] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 33.257165] ? ext4_da_write_begin+0x10c0/0x10c0 [ 33.262259] ? current_time+0x16/0xb0 [ 33.266052] ? mark_held_locks+0xa6/0xf0 [ 33.270104] ? timespec_trunc+0xc9/0x140 [ 33.274144] ? put_itimerspec64+0x1c0/0x1c0 [ 33.278463] ? trace_hardirqs_on_caller+0x37b/0x540 [ 33.283461] ? current_kernel_time64+0xb6/0x100 [ 33.288123] ? current_time+0x89/0xb0 [ 33.291922] ? filemap_check_errors+0x8b/0xb0 [ 33.296412] generic_file_direct_write+0x1e4/0x430 [ 33.301323] __generic_file_write_iter+0x209/0x550 [ 33.306249] ? generic_write_checks+0x252/0x410 [ 33.310900] ext4_file_write_iter+0x58f/0xdb0 [ 33.315375] ? ext4_llseek+0x7f0/0x7f0 [ 33.319246] do_iter_readv_writev+0x379/0x580 [ 33.323740] ? clone_verify_area+0x1e0/0x1e0 [ 33.328136] ? avc_policy_seqno+0x5/0x10 [ 33.332178] ? security_file_permission+0x88/0x1e0 [ 33.337098] do_iter_write+0x152/0x550 [ 33.340965] vfs_iter_write+0x70/0xa0 [ 33.344758] iter_file_splice_write+0x560/0xa50 [ 33.349411] ? vmsplice_to_user+0x1e0/0x1e0 [ 33.353733] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 33.359176] ? rcu_read_lock_sched_held+0x10a/0x130 [ 33.364211] ? vmsplice_to_user+0x1e0/0x1e0 [ 33.368512] SyS_splice+0xcd6/0x1270 [ 33.372209] ? filp_open+0x60/0x60 [ 33.375770] ? SyS_recv+0x40/0x40 [ 33.379200] ? compat_SyS_vmsplice+0x150/0x150 [ 33.383801] ? do_syscall_64+0x43/0x520 [ 33.387754] ? compat_SyS_vmsplice+0x150/0x150 [ 33.392314] do_syscall_64+0x19b/0x520 [ 33.396193] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.401376] RIP: 0033:0x440309 [ 33.404542] RSP: 002b:00007fffc2be67d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 33.412228] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440309 [ 33.419474] RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000004 [ 33.426724] RBP: 00000000006ca018 R08: 00000000ffffffff R09: 0000000000000000 [ 33.433983] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b90 [ 33.441245] R13: 0000000000401c20 R14: 0000000000000000 R15: 0000000000000000 [ 33.448497] Code: 2c b6 e8 85 69 e9 ff 0f 0b e8 0e bc cd ff 48 8b 84 24 e8 00 00 00 48 8d 78 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 37 a0 00 00 48 8b 84 24 e8 00 00 00 4c 8b 60 [ 33.467591] RIP: __blockdev_direct_IO+0x1dcf/0xe24e RSP: ffff8881cffaf330 [ 33.474884] ---[ end trace 19c539c5356bfb37 ]--- [ 33.479667] Kernel panic - not syncing: Fatal exception [ 33.485615] Kernel Offset: 0x33400000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 33.496533] Rebooting in 86400 seconds..