loop0: detected capacity change from 0 to 32768
loop0: detected capacity change from 32768 to 32767
BUG at fs/jfs/jfs_dmap.c:3070 assert(n < 4)
------------[ cut here ]------------
kernel BUG at fs/jfs/jfs_dmap.c:3070!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5325 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 04/01/2014
RIP: 0010:dbFindLeaf+0x51d/0x520 fs/jfs/jfs_dmap.c:3070
Code: e9 4c ff ff ff e8 83 2a 65 fe 48 c7 c7 20 cf 0b 8c 48 c7 c6 60 cc 0b 8c ba fe 0b 00 00 48 c7 c1 40 da 0b 8c e8 d4 06 c7 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:ffffc9000313f150 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 4914624e9f1a4000
RDX: ffffc90020802000 RSI: 0000000000001d33 RDI: 0000000000001d34
RBP: 000000000a04ffff R08: ffffc9000313eec7 R09: 1ffff92000627dd8
R10: dffffc0000000000 R11: fffff52000627dd9 R12: 0000000000000000
R13: 0000000000000010 R14: 000000000000000d R15: 0000000000000155
FS:  00007f17ddf056c0(0000) GS:ffff88808c881000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb256f97000 CR3: 0000000040860000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 dbAllocDmapLev+0x60/0x3c0 fs/jfs/jfs_dmap.c:2056
 dbAllocCtl+0x14a/0x9c0 fs/jfs/jfs_dmap.c:1912
 dbAllocAG+0x1e6/0xf80 fs/jfs/jfs_dmap.c:1440
 dbAlloc+0x5ab/0xba0 fs/jfs/jfs_dmap.c:964
 dtSplitUp fs/jfs/jfs_dtree.c:979 [inline]
 dtInsert+0xb27/0x5cd0 fs/jfs/jfs_dtree.c:868
 jfs_create+0x75b/0xb10 fs/jfs/namei.c:138
 lookup_open fs/namei.c:4511 [inline]
 open_last_lookups fs/namei.c:4611 [inline]
 path_openat+0x1395/0x3860 fs/namei.c:4855
 do_file_open+0x23e/0x4a0 fs/namei.c:4887
 do_sys_openat2+0x113/0x200 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f17dcf9cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f17ddf04fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f17dd215fa0 RCX: 00007f17dcf9cdd9
RDX: 0000000000143042 RSI: 0000200000000800 RDI: ffffffffffffff9c
RBP: 00007f17dd032d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000088 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f17dd216038 R14: 00007f17dd215fa0 R15: 00007ffc4d5eb5e8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x51d/0x520 fs/jfs/jfs_dmap.c:3070
Code: e9 4c ff ff ff e8 83 2a 65 fe 48 c7 c7 20 cf 0b 8c 48 c7 c6 60 cc 0b 8c ba fe 0b 00 00 48 c7 c1 40 da 0b 8c e8 d4 06 c7 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:ffffc9000313f150 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 4914624e9f1a4000
RDX: ffffc90020802000 RSI: 0000000000001d33 RDI: 0000000000001d34
RBP: 000000000a04ffff R08: ffffc9000313eec7 R09: 1ffff92000627dd8
R10: dffffc0000000000 R11: fffff52000627dd9 R12: 0000000000000000
R13: 0000000000000010 R14: 000000000000000d R15: 0000000000000155
FS:  00007f17ddf056c0(0000) GS:ffff88808c881000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f17ddec2fe8 CR3: 0000000040860000 CR4: 0000000000352ef0