loop0: detected capacity change from 0 to 32768
------------[ cut here ]------------
lp >= size || lp < 0
WARNING: fs/jfs/jfs_dmap.c:2962 at dbAdjTree+0x3ac/0x430 fs/jfs/jfs_dmap.c:2962, CPU#0: syz.0.0/5319
Modules linked in:
CPU: 0 UID: 0 PID: 5319 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:dbAdjTree+0x3ac/0x430 fs/jfs/jfs_dmap.c:2962
Code: 5f fe eb 0c e8 95 2c 5f fe eb 05 e8 8e 2c 5f fe 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 75 2c 5f fe 90 <0f> 0b 90 eb e1 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c 8c fc ff ff
RSP: 0018:ffffc9000f31efe8 EFLAGS: 00010287
RAX: ffffffff8367e53b RBX: 0000000000002057 RCX: 0000000000100000
RDX: ffffc9000e9b2000 RSI: 000000000000cc4c RDI: 000000000000cc4d
RBP: 0000000000000005 R08: 0000000000000000 R09: 1ffffd4000289180
R10: dffffc0000000000 R11: fffff94000289181 R12: ffff888051230018
R13: dffffc0000000000 R14: ffff888051230010 R15: 0000000000000155
FS:  00007f179a5f56c0(0000) GS:ffff88808c549000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f577f9dc000 CR3: 000000001f5fd000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 dbSplit+0x132/0x200 fs/jfs/jfs_dmap.c:2735
 dbAllocBits+0x4c4/0xa00 fs/jfs/jfs_dmap.c:2280
 dbAllocDmap+0x64/0x140 fs/jfs/jfs_dmap.c:2121
 dbAlloc+0x46c/0xba0 fs/jfs/jfs_dmap.c:892
 extBalloc fs/jfs/jfs_extent.c:336 [inline]
 extAlloc+0x57d/0x1010 fs/jfs/jfs_extent.c:127
 jfs_get_block+0x351/0xad0 fs/jfs/inode.c:254
 __block_write_begin_int+0x6c2/0x1900 fs/buffer.c:2123
 block_write_begin+0x8d/0x120 fs/buffer.c:2234
 jfs_write_begin+0x35/0x80 fs/jfs/inode.c:306
 generic_perform_write+0x2d5/0x8f0 mm/filemap.c:4364
 generic_file_write_iter+0xae/0x330 mm/filemap.c:4507
 iter_file_splice_write+0xa31/0x1240 fs/splice.c:736
 do_splice_from fs/splice.c:936 [inline]
 direct_splice_actor+0x101/0x160 fs/splice.c:1159
 splice_direct_to_actor+0x57b/0xcb0 fs/splice.c:1103
 do_splice_direct_actor fs/splice.c:1202 [inline]
 do_splice_direct+0x195/0x290 fs/splice.c:1228
 do_sendfile+0x52e/0x7c0 fs/read_write.c:1371
 __do_sys_sendfile64 fs/read_write.c:1432 [inline]
 __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1418
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f179e19e0d9
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:00007f179a5f4fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f179e425fa0 RCX: 00007f179e19e0d9
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005
RBP: 00007f179e235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0001000000201005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f179e426038 R14: 00007f179e425fa0 R15: 00007ffc111dbb18
 </TASK>