loop0: detected capacity change from 32768 to 32767
BUG at fs/jfs/jfs_dmap.c:2983 assert(n < 4)
------------[ cut here ]------------
kernel BUG at fs/jfs/jfs_dmap.c:2983!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5353 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:dbFindLeaf+0x51d/0x520 fs/jfs/jfs_dmap.c:2983
Code: e9 4c ff ff ff e8 63 92 7f fe 48 c7 c7 c0 ec c3 8b 48 c7 c6 00 ea c3 8b ba a7 0b 00 00 48 c7 c1 80 f7 c3 8b e8 74 77 e7 fd 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57
RSP: 0018:ffffc9000d4df168 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: a775c9394c808d00
RDX: ffffc9000e923000 RSI: 00000000000020e3 RDI: 00000000000020e4
RBP: 000000000a04ffff R08: ffffc9000d4dee87 R09: 1ffff92001a9bdd0
R10: dffffc0000000000 R11: fffff52001a9bdd1 R12: 0000000000000000
R13: 0000000000000010 R14: 000000000000000d R15: 0000000000000155
FS:  00007f919ab676c0(0000) GS:ffff88808d210000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007eff775de000 CR3: 0000000033cd1000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 dbAllocDmapLev+0x60/0x3c0 fs/jfs/jfs_dmap.c:1969
 dbAllocCtl+0x14a/0x9c0 fs/jfs/jfs_dmap.c:1825
 dbAllocAG+0x1e6/0xff0 fs/jfs/jfs_dmap.c:1353
 dbAlloc+0x5a8/0xba0 fs/jfs/jfs_dmap.c:877
 dtSplitUp fs/jfs/jfs_dtree.c:982 [inline]
 dtInsert+0xad5/0x5f40 fs/jfs/jfs_dtree.c:871
 jfs_create+0x6c8/0xa80 fs/jfs/namei.c:137
 lookup_open fs/namei.c:3708 [inline]
 open_last_lookups fs/namei.c:3807 [inline]
 path_openat+0x14f4/0x3830 fs/namei.c:4043
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_creat fs/open.c:1528 [inline]
 __se_sys_creat fs/open.c:1522 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1522
 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: 0033:0x7f9199d8ebe9
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:00007f919ab67038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f9199fb6090 RCX: 00007f9199d8ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000e00
RBP: 00007f9199e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9199fb6128 R14: 00007f9199fb6090 R15: 00007fff9ccf3678
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x51d/0x520 fs/jfs/jfs_dmap.c:2983
Code: e9 4c ff ff ff e8 63 92 7f fe 48 c7 c7 c0 ec c3 8b 48 c7 c6 00 ea c3 8b ba a7 0b 00 00 48 c7 c1 80 f7 c3 8b e8 74 77 e7 fd 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57
RSP: 0018:ffffc9000d4df168 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: a775c9394c808d00
RDX: ffffc9000e923000 RSI: 00000000000020e3 RDI: 00000000000020e4
RBP: 000000000a04ffff R08: ffffc9000d4dee87 R09: 1ffff92001a9bdd0
R10: dffffc0000000000 R11: fffff52001a9bdd1 R12: 0000000000000000
R13: 0000000000000010 R14: 000000000000000d R15: 0000000000000155
FS:  00007f919ab676c0(0000) GS:ffff88808d210000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f919ab45fc8 CR3: 0000000033cd1000 CR4: 0000000000352ef0