loop0: detected capacity change from 32768 to 0
gfs2: fsid=syz:syz.0: quota exceeded for group 0
gfs2: fsid=syz:syz.0: fatal: I/O error - block = 9474, function = gfs2_ail1_empty_one, file = fs/gfs2/log.c, line = 328
gfs2: fsid=syz:syz.0: about to withdraw this file system
gfs2: fsid=syz:syz.0: Journal recovery skipped for jid 0 until next mount.
gfs2: fsid=syz:syz.0: Glock dequeues delayed: 0
gfs2: fsid=syz:syz.0: File system withdrawn
CPU: 0 UID: 60928 PID: 5360 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
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 gfs2_withdraw+0xb30/0x1430 fs/gfs2/util.c:345
 revoke_lo_before_commit+0x2f/0xe60 fs/gfs2/lops.c:857
 lops_before_commit fs/gfs2/lops.h:42 [inline]
 gfs2_log_flush+0xb88/0x24c0 fs/gfs2/log.c:1105
 do_sync+0xa1d/0xc60 fs/gfs2/quota.c:981
 gfs2_quota_unlock+0x6f8/0x8a0 fs/gfs2/quota.c:1186
 gfs2_iomap_begin_write fs/gfs2/bmap.c:-1 [inline]
 gfs2_iomap_begin+0xc14/0x11c0 fs/gfs2/bmap.c:1133
 iomap_iter+0x531/0xde0 fs/iomap/iter.c:108
 iomap_file_buffered_write+0x7fa/0x9b0 fs/iomap/buffered-io.c:1065
 gfs2_file_buffered_write+0x4ed/0x880 fs/gfs2/file.c:1061
 gfs2_file_write_iter+0x94e/0x1100 fs/gfs2/file.c:1166
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c6/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff1cc18ebe9
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:00007ff1ccf39038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ff1cc3c6090 RCX: 00007ff1cc18ebe9
RDX: 0000000000001006 RSI: 00002000000005c0 RDI: 0000000000000004
RBP: 00007ff1cc211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff1cc3c6128 R14: 00007ff1cc3c6090 R15: 00007fff429c9c98
 </TASK>
------------[ cut here ]------------
kernel BUG at fs/gfs2/quota.c:331!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 60928 PID: 5360 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:qd_put+0x18a/0x190 fs/gfs2/quota.c:331
Code: e7 e8 ba 08 28 fe e9 ee fe ff ff 89 e9 80 e1 07 80 c1 03 38 c1 7c 83 48 89 ef e8 91 09 28 fe e9 76 ff ff ff e8 a7 18 c3 fd 90 <0f> 0b 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000d4b73e8 EFLAGS: 00010287
RAX: ffffffff83fca5e9 RBX: ffff8880455e6000 RCX: 0000000000100000
RDX: ffffc9000eb23000 RSI: 00000000000335ab RDI: 00000000000335ac
RBP: 00000000ffffff80 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52001a96e64 R12: ffff8880455e6070
R13: dffffc0000000000 R14: ffff8880455e6030 R15: 1ffff11008abcc0e
FS:  00007ff1ccf396c0(0000) GS:ffff88808d20c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cc9de5c618 CR3: 0000000042fe5000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 gfs2_quota_unhold+0x1c9/0x690 fs/gfs2/quota.c:653
 gfs2_quota_unlock+0x7bd/0x8a0 fs/gfs2/quota.c:1191
 gfs2_iomap_begin_write fs/gfs2/bmap.c:-1 [inline]
 gfs2_iomap_begin+0xc14/0x11c0 fs/gfs2/bmap.c:1133
 iomap_iter+0x531/0xde0 fs/iomap/iter.c:108
 iomap_file_buffered_write+0x7fa/0x9b0 fs/iomap/buffered-io.c:1065
 gfs2_file_buffered_write+0x4ed/0x880 fs/gfs2/file.c:1061
 gfs2_file_write_iter+0x94e/0x1100 fs/gfs2/file.c:1166
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c6/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff1cc18ebe9
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:00007ff1ccf39038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ff1cc3c6090 RCX: 00007ff1cc18ebe9
RDX: 0000000000001006 RSI: 00002000000005c0 RDI: 0000000000000004
RBP: 00007ff1cc211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff1cc3c6128 R14: 00007ff1cc3c6090 R15: 00007fff429c9c98
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:qd_put+0x18a/0x190 fs/gfs2/quota.c:331
Code: e7 e8 ba 08 28 fe e9 ee fe ff ff 89 e9 80 e1 07 80 c1 03 38 c1 7c 83 48 89 ef e8 91 09 28 fe e9 76 ff ff ff e8 a7 18 c3 fd 90 <0f> 0b 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000d4b73e8 EFLAGS: 00010287
RAX: ffffffff83fca5e9 RBX: ffff8880455e6000 RCX: 0000000000100000
RDX: ffffc9000eb23000 RSI: 00000000000335ab RDI: 00000000000335ac
RBP: 00000000ffffff80 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52001a96e64 R12: ffff8880455e6070
R13: dffffc0000000000 R14: ffff8880455e6030 R15: 1ffff11008abcc0e
FS:  00007ff1ccf396c0(0000) GS:ffff88808d20c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cc9de5c618 CR3: 0000000042fe5000 CR4: 0000000000352ef0