loop0: detected capacity change from 0 to 32768
BTRFS: device fsid 395ef67a-297e-477c-816d-cd80a5b93e5d devid 1 transid 8 /dev/loop0 (7:0) scanned by syz.0.0 (5344)
BTRFS info (device loop0): first mount of filesystem 395ef67a-297e-477c-816d-cd80a5b93e5d
BTRFS info (device loop0): using sha256 (sha256-lib) checksum algorithm
BTRFS info (device loop0): enabling ssd optimizations
BTRFS info (device loop0): turning on async discard
BTRFS info (device loop0): enabling free space tree
loop0: detected capacity change from 32768 to 64
assertion failed: prealloc == NULL :: 0, in fs/btrfs/qgroup.c:3529
------------[ cut here ]------------
kernel BUG at fs/btrfs/qgroup.c:3529!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5344 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:btrfs_qgroup_inherit+0x2892/0x28a0 fs/btrfs/qgroup.c:3529
Code: ff ff e8 61 87 d2 fd 48 c7 c7 a0 4b d1 8b 48 c7 c6 00 4c d1 8b 31 d2 48 c7 c1 20 48 d1 8b 41 b8 c9 0d 00 00 e8 3f 71 38 fd 90 <0f> 0b 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000e347300 EFLAGS: 00010246
RAX: 0000000000000042 RBX: 0000000000000000 RCX: cfab939672445400
RDX: ffffc90020802000 RSI: 000000000000db21 RDI: 000000000000db22
RBP: ffffc9000e347548 R08: ffffc9000e347027 R09: 1ffff92001c68e04
R10: dffffc0000000000 R11: fffff52001c68e05 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00000000fffffffb
FS:  00007f2b0c4926c0(0000) GS:ffff88808d22f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd2a99fc54 CR3: 0000000011415000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 qgroup_account_snapshot+0x183/0x4a0 fs/btrfs/transaction.c:1601
 create_pending_snapshot+0xead/0x3230 fs/btrfs/transaction.c:1870
 create_pending_snapshots+0x17c/0x1c0 fs/btrfs/transaction.c:1940
 btrfs_commit_transaction+0xf78/0x3b10 fs/btrfs/transaction.c:2430
 create_snapshot fs/btrfs/ioctl.c:779 [inline]
 btrfs_mksubvol+0xc75/0x12c0 fs/btrfs/ioctl.c:926
 btrfs_mksnapshot+0xab/0xf0 fs/btrfs/ioctl.c:968
 __btrfs_ioctl_snap_create+0x520/0x730 fs/btrfs/ioctl.c:1232
 btrfs_ioctl_snap_create+0x131/0x180 fs/btrfs/ioctl.c:1259
 btrfs_ioctl+0x447/0xd00 fs/btrfs/ioctl.c:-1
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2b0b58f7c9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2b0c492038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2b0b7e5fa0 RCX: 00007f2b0b58f7c9
RDX: 0000200000000200 RSI: 0000000050009401 RDI: 0000000000000003
RBP: 00007f2b0b613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2b0b7e6038 R14: 00007f2b0b7e5fa0 R15: 00007fffafec3e98
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:btrfs_qgroup_inherit+0x2892/0x28a0 fs/btrfs/qgroup.c:3529
Code: ff ff e8 61 87 d2 fd 48 c7 c7 a0 4b d1 8b 48 c7 c6 00 4c d1 8b 31 d2 48 c7 c1 20 48 d1 8b 41 b8 c9 0d 00 00 e8 3f 71 38 fd 90 <0f> 0b 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000e347300 EFLAGS: 00010246
RAX: 0000000000000042 RBX: 0000000000000000 RCX: cfab939672445400
RDX: ffffc90020802000 RSI: 000000000000db21 RDI: 000000000000db22
RBP: ffffc9000e347548 R08: ffffc9000e347027 R09: 1ffff92001c68e04
R10: dffffc0000000000 R11: fffff52001c68e05 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00000000fffffffb
FS:  00007f2b0c4926c0(0000) GS:ffff88808d22f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2b0c3156a0 CR3: 0000000011415000 CR4: 0000000000352ef0