loop0: detected capacity change from 0 to 32768
BUG at fs/jfs/jfs_dmap.c:2948 assert(n < 4)
------------[ cut here ]------------
kernel BUG at fs/jfs/jfs_dmap.c:2948!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 5601 Comm: syz-executor.0 Not tainted 6.2.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
RIP: 0010:dbFindLeaf+0x3a9/0x3b0 fs/jfs/jfs_dmap.c:2948
Code: fe 48 89 ea e9 4f ff ff ff 48 c7 c7 00 0d ed 89 48 c7 c6 c0 1a ed 89 ba 84 0b 00 00 48 c7 c1 a0 17 ed 89 31 c0 e8 d7 f3 92 06 <0f> 0b 0f 1f 44 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 60 48
RSP: 0018:ffffc900047ff320 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000003 RCX: 3644e35902341100
RDX: 1ffff920008ffe1c RSI: ffffffff8a0c24a0 RDI: 0000000000000001
RBP: 00000000001cb703 R08: dffffc0000000000 R09: fffff520008ffe21
R10: fffff520008ffe21 R11: 1ffff920008ffe20 R12: ffff88807a9f3010
R13: 0000000000000019 R14: 0000000000000000 R15: 000000000000001c
FS:  00007fe6b6a6f700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558a232dade0 CR3: 0000000021eb6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 dbAllocDmapLev+0x9a/0x3a0 fs/jfs/jfs_dmap.c:1952
 dbAlloc+0x665/0xa30 fs/jfs/jfs_dmap.c:840
 extBalloc fs/jfs/jfs_extent.c:321 [inline]
 extAlloc+0x3ec/0xd30 fs/jfs/jfs_extent.c:122
 jfs_get_block+0x2c2/0xb80 fs/jfs/inode.c:248
 __block_write_begin_int+0x37a/0x1220 fs/buffer.c:1991
 __block_write_begin fs/buffer.c:2041 [inline]
 block_write_begin+0x6e/0x140 fs/buffer.c:2102
 jfs_write_begin+0x25/0x50 fs/jfs/inode.c:299
 generic_perform_write+0x2bb/0x510 mm/filemap.c:3772
 __generic_file_write_iter+0x13f/0x340 mm/filemap.c:3900
 generic_file_write_iter+0x99/0x230 mm/filemap.c:3932
 do_iter_write+0x632/0xa90 fs/read_write.c:861
 vfs_writev fs/read_write.c:934 [inline]
 do_writev+0x1de/0x3a0 fs/read_write.c:977
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe6b588a5a9
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe6b6a6f168 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007fe6b59abf80 RCX: 00007fe6b588a5a9
RDX: 0000000000000001 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00007fe6b58e5580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffe364958f R14: 00007fe6b6a6f300 R15: 0000000000022000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x3a9/0x3b0 fs/jfs/jfs_dmap.c:2948
Code: fe 48 89 ea e9 4f ff ff ff 48 c7 c7 00 0d ed 89 48 c7 c6 c0 1a ed 89 ba 84 0b 00 00 48 c7 c1 a0 17 ed 89 31 c0 e8 d7 f3 92 06 <0f> 0b 0f 1f 44 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 60 48
RSP: 0018:ffffc900047ff320 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000003 RCX: 3644e35902341100
RDX: 1ffff920008ffe1c RSI: ffffffff8a0c24a0 RDI: 0000000000000001
RBP: 00000000001cb703 R08: dffffc0000000000 R09: fffff520008ffe21
R10: fffff520008ffe21 R11: 1ffff920008ffe20 R12: ffff88807a9f3010
R13: 0000000000000019 R14: 0000000000000000 R15: 000000000000001c
FS:  00007fe6b6a6f700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561f4bfae000 CR3: 0000000021eb6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400