WARNING: CPU: 1 PID: 15358 at fs/fuse/dev.c:390 request_end+0x82e/0xaa0 fs/fuse/dev.c:390
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 15358 Comm: syz-executor5 Not tainted 4.19.0-rc5-next-20180925+ #79
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
kobject: 'loop0' (00000000e0950edf): kobject_uevent_env
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d3/0x2c4 lib/dump_stack.c:113
kobject: 'loop4' (00000000335fb77d): kobject_uevent_env
 panic+0x238/0x4e7 kernel/panic.c:184
kobject: 'loop4' (00000000335fb77d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop0' (00000000e0950edf): fill_kobj_path: path = '/devices/virtual/block/loop0'
 __warn.cold.8+0x163/0x1ba kernel/panic.c:536
 report_bug+0x254/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:969
RIP: 0010:request_end+0x82e/0xaa0 fs/fuse/dev.c:390
Code: 3c 03 0f 8f 6f fe ff ff 48 8b bd f0 fe ff ff e8 f8 a0 38 ff e9 5e fe ff ff e8 1e 1e f5 fe 0f 0b e9 b0 fa ff ff e8 12 1e f5 fe <0f> 0b e9 f0 fa ff ff e8 26 32 bf fe e8 f1 a0 38 ff e9 5b fb ff ff
RSP: 0018:ffff88018a0df378 EFLAGS: 00010216
RAX: 0000000000040000 RBX: ffff8801c0186c00 RCX: ffffc90004270000
RDX: 0000000000000134 RSI: ffffffff82883bae RDI: 0000000000000007
RBP: ffff88018a0df4a8 R08: ffff8801970dc340 R09: ffffed003ab7176f
R10: ffffed003ab7176f R11: ffff8801d5b8bb7b R12: 1ffff1003141be74
R13: ffff8801d5b8bb00 R14: ffff8801c0186c30 R15: ffff88018a0df480
FAT-fs (loop4): bogus number of reserved sectors
FAT-fs (loop4): Can't find a valid FAT filesystem
 fuse_dev_do_write+0x1926/0x36c0 fs/fuse/dev.c:1915
 fuse_dev_write+0x19a/0x240 fs/fuse/dev.c:1939
 call_write_iter include/linux/fs.h:1825 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x6b8/0x9f0 fs/read_write.c:487
 vfs_write+0x1fc/0x560 fs/read_write.c:549
 ksys_write+0x101/0x260 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 1d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5571482c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000000000078 RSI: 0000000020000680 RDI: 0000000000000005
RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f55714836d4
R13: 00000000004c4ed2 R14: 00000000004d8408 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..