[syzbot] [btrfs?] WARNING in btrfs_relocate_block_group

From: syzbot
Date: Sat May 20 2023 - 10:55:55 EST


Hello,

syzbot found the following issue on:

HEAD commit: 1b66c114d161 Merge tag 'nfsd-6.4-1' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=160f9dd9280000
kernel config: https://syzkaller.appspot.com/x/.config?x=94af80bb8ddd23c4
dashboard link: https://syzkaller.appspot.com/bug?extid=07a7e6273e07bda9ef8b
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=122229f9280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2e240bb8f051/disk-1b66c114.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f68505e2033a/vmlinux-1b66c114.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b5b233cfac6d/bzImage-1b66c114.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/92afd11e51ee/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+07a7e6273e07bda9ef8b@xxxxxxxxxxxxxxxxxxxxxxxxx

BTRFS info (device loop0): relocating block group 6881280 flags data|metadata
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5901 at fs/btrfs/relocation.c:4123 btrfs_relocate_block_group+0xcda/0xd70
Modules linked in:
CPU: 1 PID: 5901 Comm: syz-executor.0 Not tainted 6.4.0-rc2-syzkaller-00015-g1b66c114d161 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
RIP: 0010:btrfs_relocate_block_group+0xcda/0xd70 fs/btrfs/relocation.c:4123
Code: fe 48 c7 c7 80 2e 2b 8b 48 c7 c6 20 2e 2b 8b ba b1 0f 00 00 e8 b7 c4 10 07 e8 e2 e2 ee fd 0f 0b e9 62 fd ff ff e8 d6 e2 ee fd <0f> 0b e9 b5 fd ff ff e8 ca e2 ee fd 0f 0b e9 08 fe ff ff 44 89 e1
RSP: 0018:ffffc9000ae1fa28 EFLAGS: 00010293
RAX: ffffffff839c99ca RBX: 0000000000190000 RCX: ffff88806f4d0000
RDX: 0000000000000000 RSI: 0000000000190000 RDI: 0000000000000000
RBP: ffff88806d673068 R08: ffffffff839c9778 R09: fffff520015c3f35
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88806e4e2000
R13: 0000000000000000 R14: ffff88806e750000 R15: ffff88806e750010
FS: 00007fdf35b02700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe4fb4e6000 CR3: 000000002079a000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3276
__btrfs_balance+0x1b06/0x2690 fs/btrfs/volumes.c:4011
btrfs_balance+0xbdb/0x1120 fs/btrfs/volumes.c:4395
btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3599
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fdf34e8c169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fdf35b02168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fdf34fac050 RCX: 00007fdf34e8c169
RDX: 00000000200003c0 RSI: 00000000c4009420 RDI: 0000000000000005
RBP: 00007fdf34ee7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff060f715f R14: 00007fdf35b02300 R15: 0000000000022000
</TASK>


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