WARNING in btrfs_destroy_inode

[shankarapailoor]

Hi,

I'm using Syzkaller to fuzz linux 4.18.0-rc1 with btrfs and found the
following WARNING crash. I have a C program that reproduces it here:
https://pastebin.com/bBzmrGFH

WARNING: CPU: 1 PID: 12788 at fs/btrfs/inode.c:9288
btrfs_destroy_inode+0x545/0x720  fs/btrfs/inode.c:9288

Kernel panic - not syncing: panic_on_warn set ...CPU: 1 PID: 12788
Comm: syz-executor5 Not tainted 4.18.0-rc1+ #35
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 01/01/2011
Call Trace:
   __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x148/0x1b5
lib/dump_stack.c:113
   panic+0x200/0x42c kernel/panic.c:184
   __warn+0x1ea/0x200 kernel/panic.c:536
   report_bug+0x1f4/0x2b0 lib/bug.c:186
   fixup_bug.part.10+0x37/0x80 arch/x86/kernel/traps.c:178
   fixup_bug arch/x86/kernel/traps.c:248 [inline]
   do_error_trap+0x288/0x2e0 arch/x86/kernel/traps.c:296
   do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
    invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
RIP: 0010:btrfs_destroy_inode+0x545/0x720 fs/btrfs/inode.c:9288
Code: ff e8 4f 6c 52 ff 0f 0b e9 ed fb ff ff e8 43 6c 52 ff 0f 0b e9
c8 fc ff ff e8 37 6c 52 ff 0f 0b e9 f2 fc ff ff e8 2b 6c 52 ff <0f> 0b
e9 93 fb ff ff e8 1f 6c 52 ff 0f 0b e9 38 fc ff ff e8 13 6c
RSP: 0018:ffff880091287c68 EFLAGS: 00010293
RAX: ffff88009d0a8340 RBX: ffff8800a65c36a8 RCX: ffffffff820ef895
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8800a65c3598
RBP: ffff880091287cb0 R08: ffffed00169d02bf R09: 0000000000000001
R10: ffffed00169d02be R11: ffff8800b4e815f7 R12: ffff8800a65c3240
R13: ffff8800b448c1c0 R14: ffff8800a65c3878 R15: ffffffff855cbc40
    destroy_inode+0xc3/0x120 fs/inode.c:267
    evict+0x3d4/0x620 fs/inode.c:575
    iput_final fs/inode.c:1506 [inline]
    iput+0x4e8/0x760 fs/inode.c:1532
    do_unlinkat+0x398/0x670 fs/namei.c:4079
    __do_sys_unlink fs/namei.c:4120 [inline]
    __se_sys_unlink fs/namei.c:4118 [inline]
    __x64_sys_unlink+0x42/0x50 fs/namei.c:4118
    do_syscall_64+0xda/0x560 arch/x86/entry/common.c:290
    entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455757
Code: 0f 1f 00 b8 58 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 bd bc fb
ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 57 00 00 00 0f 05 <48> 3d
01 f0 ff ff 0f 83 9d bc fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffe629f058 EFLAGS: 00000202 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455757
RDX: 0000000002980a13 RSI: 00007fffe629f0f0 RDI: 00007fffe629f0f0
RBP: 00007fffe62a0e00 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000005 R11: 0000000000000202 R12: 0000000002980940
R13: 0000000000000000 R14: 0000000000000117 R15: 000000000008e36d


My kernel configs: https://pastebin.com/KFcaLxhj

Please let me know if I can provide more information.

-- 
Regards,
Shankara Pailoor