[syzbot] WARNING in btrfs_add_link

syzbot
2022-10-18T07:04:54Z

Hello,

syzbot found the following issue on:

HEAD commit: 55be6084c8e0 Merge tag 'timers-core-2022-10-05' of git://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1298899a880000
kernel config: https://syzkaller.appspot.com/x/.config?x=df75278aabf0681a
dashboard link: https://syzkaller.appspot.com/bug?extid=b531e31d583db14070d4
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6c791937c012/disk-55be6084.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cb21a2879b4c/vmlinux-55be6084.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b531e31d583db14070d4@syzkaller.appspotmail.com

loop1: detected capacity change from 0 to 32768
BTRFS info (device loop1): using xxhash64 (xxhash64-generic) checksum algorithm
BTRFS info (device loop1): using free space tree
BTRFS info (device loop1): enabling ssd optimizations
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1681 at fs/btrfs/inode.c:6568 btrfs_add_link+0xab5/0xd50 fs/btrfs/inode.c:6568
Modules linked in:
CPU: 1 PID: 1681 Comm: syz-executor.1 Not tainted 6.0.0-syzkaller-09589-g55be6084c8e0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
RIP: 0010:btrfs_add_link+0xab5/0xd50 fs/btrfs/inode.c:6568
Code: f7 1d fe 44 89 ee bf e2 ff ff ff e8 f5 f3 1d fe 41 83 fd e2 74 6a e8 2a f7 1d fe 44 89 ee 48 c7 c7 40 9c 37 8a e8 2a db e0 05 <0f> 0b bb 01 00 00 00 e8 0f f7 1d fe 41 89 d8 44 89 e9 ba a8 19 00
RSP: 0018:ffffc90003f2f510 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88809c91c000 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff81612e28 RDI: fffff520007e5e94
RBP: ffffc90003f2f620 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 00000000312d2072 R12: ffff88809ded3c20
R13: 00000000fffffff4 R14: 0000000000000108 R15: ffff888047aba000
FS: 00007efc740b9700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563379fb8c78 CR3: 00000000a763e000 CR4: 0000000000350ef0
Call Trace:
<TASK>
btrfs_create_new_inode+0x1b46/0x2890 fs/btrfs/inode.c:6504
btrfs_create_common+0x1d5/0x260 fs/btrfs/inode.c:6639
btrfs_create+0x112/0x160 fs/btrfs/inode.c:6679
lookup_open.isra.0+0xf05/0x12a0 fs/namei.c:3413
open_last_lookups fs/namei.c:3481 [inline]
path_openat+0x996/0x28f0 fs/namei.c:3688
do_filp_open+0x1b6/0x400 fs/namei.c:3718
do_sys_openat2+0x16d/0x4c0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_open fs/open.c:1334 [inline]
__se_sys_open fs/open.c:1330 [inline]
__x64_sys_open+0x119/0x1c0 fs/open.c:1330
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7efc72e8b5a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efc740b9168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007efc72fabf80 RCX: 00007efc72e8b5a9
RDX: 0000000000000000 RSI: 0000000000143142 RDI: 0000000020002000
RBP: 00007efc740b91d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffc75a878af R14: 00007efc740b9300 R15: 0000000000022000
</TASK>

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