[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 43.110690] audit: type=1800 audit(1547759197.927:25): pid=7894 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 43.137897] audit: type=1800 audit(1547759197.927:26): pid=7894 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 43.157990] audit: type=1800 audit(1547759197.927:27): pid=7894 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.129' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 55.242758] kasan: CONFIG_KASAN_INLINE enabled [ 55.247448] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 55.254920] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 55.261151] CPU: 1 PID: 8044 Comm: syz-executor668 Not tainted 5.0.0-rc2+ #30 [ 55.268402] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 55.277748] RIP: 0010:fuse_dev_do_write+0x1e44/0x3780 [ 55.282949] Code: 00 48 c1 e0 2a 80 3c 02 00 0f 85 d5 18 00 00 49 8b 9f 58 01 00 00 b8 ff ff 37 00 48 c1 e0 2a 48 8d 7b 04 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 39 [ 55.301836] RSP: 0018:ffff888082d476d8 EFLAGS: 00010247 [ 55.307195] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff828b9c2a [ 55.314444] RDX: 0000000000000000 RSI: ffffffff828b9c3c RDI: 0000000000000004 [ 55.321694] RBP: ffff888082d47aa8 R08: ffff8880951de3c0 R09: ffffed1013e49f7f [ 55.328942] R10: ffffed1013e49f7e R11: ffff88809f24fbf3 R12: 0000000000000000 [ 55.336194] R13: 0000000000000000 R14: 0000000000000030 R15: ffff88809f24fbd0 [ 55.343450] FS: 000000000259a880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 55.351657] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 55.357521] CR2: 0000000000455060 CR3: 00000000a4c1d000 CR4: 00000000001406e0 [ 55.364775] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 55.372023] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 55.379268] Call Trace: [ 55.381845] ? fuse_dev_read+0x250/0x250 [ 55.385891] ? fuse_dev_do_read.isra.0+0x27a/0x1c90 [ 55.390891] ? print_usage_bug+0xd0/0xd0 [ 55.394941] ? fuse_dev_release+0x6b0/0x6b0 [ 55.399256] ? add_lock_to_list.isra.0+0x450/0x450 [ 55.404186] ? print_usage_bug+0xd0/0xd0 [ 55.408227] ? aa_file_perm+0x42e/0x1090 [ 55.412275] ? find_held_lock+0x35/0x120 [ 55.416324] ? aa_file_perm+0x42e/0x1090 [ 55.420531] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.426049] ? lock_downgrade+0x910/0x910 [ 55.430180] ? kasan_check_read+0x11/0x20 [ 55.434319] ? rcu_read_unlock_special+0x380/0x380 [ 55.439231] ? aa_file_perm+0x455/0x1090 [ 55.443275] ? memset+0x32/0x40 [ 55.446539] fuse_dev_write+0x191/0x240 [ 55.450505] ? fuse_dev_splice_write+0xe10/0xe10 [ 55.455260] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.460780] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 55.466299] ? iov_iter_init+0xea/0x220 [ 55.470261] __vfs_write+0x764/0xb40 [ 55.473962] ? kernel_read+0x120/0x120 [ 55.477834] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.483357] ? apparmor_file_permission+0x25/0x30 [ 55.488185] ? rw_verify_area+0x118/0x360 [ 55.492324] vfs_write+0x20c/0x580 [ 55.495845] ksys_write+0x105/0x260 [ 55.499451] ? __ia32_sys_read+0xb0/0xb0 [ 55.503495] ? trace_hardirqs_off_caller+0x300/0x300 [ 55.508578] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 55.513326] __x64_sys_write+0x73/0xb0 [ 55.517194] do_syscall_64+0x1a3/0x800 [ 55.521062] ? syscall_return_slowpath+0x5f0/0x5f0 [ 55.525971] ? prepare_exit_to_usermode+0x232/0x3b0 [ 55.530972] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 55.535800] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 55.540972] RIP: 0033:0x440279 [ 55.544148] 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 55.563036] RSP: 002b:00007ffea76828f8 EFLAGS: 00000217 ORIG_RAX: 0000000000000001 [ 55.570724] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440279 [ 55.577980] RDX: 0000000000000030 RSI: 0000000020000080 RDI: 0000000000000003 [ 55.585228] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 55.592477] R10: 00000000004002c8 R11: 0000000000000217 R12: 0000000000401b00 [ 55.599726] R13: 0000000000401b90 R14: 0000000000000000 R15: 0000000000000000 [ 55.606977] Modules linked in: [ 55.611260] ---[ end trace 265810759553c610 ]--- [ 55.616035] RIP: 0010:fuse_dev_do_write+0x1e44/0x3780 [ 55.621494] Code: 00 48 c1 e0 2a 80 3c 02 00 0f 85 d5 18 00 00 49 8b 9f 58 01 00 00 b8 ff ff 37 00 48 c1 e0 2a 48 8d 7b 04 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 39 [ 55.640457] RSP: 0018:ffff888082d476d8 EFLAGS: 00010247 [ 55.645817] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff828b9c2a [ 55.653104] RDX: 0000000000000000 RSI: ffffffff828b9c3c RDI: 0000000000000004 [ 55.660370] RBP: ffff888082d47aa8 R08: ffff8880951de3c0 R09: ffffed1013e49f7f [ 55.667677] R10: ffffed1013e49f7e R11: ffff88809f24fbf3 R12: 0000000000000000 [ 55.674969] R13: 0000000000000000 R14: 0000000000000030 R15: ffff88809f24fbd0 [ 55.682285] FS: 000000000259a880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 55.690545] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 55.696411] CR2: 0000000000455060 CR3: 00000000a4c1d000 CR4: 00000000001406e0 [ 55.703727] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 55.711025] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 55.718281] Kernel panic - not syncing: Fatal exception [ 55.724634] Kernel Offset: disabled [ 55.728256] Rebooting in 86400 seconds..