BUG at fs/jfs/jfs_dmap.c:2975 assert(n < 4)
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kernel BUG at fs/jfs/jfs_dmap.c:2975!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 6433 Comm: syz.1.53 Not tainted 6.16.0-rc4-syzkaller-00324-g1f988d0788f5 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:dbFindLeaf+0x51d/0x520 fs/jfs/jfs_dmap.c:2975
Code: e9 4c ff ff ff e8 73 ca 84 fe 48 c7 c7 00 b8 c3 8b 48 c7 c6 40 b5 c3 8b ba 9f 0b 00 00 48 c7 c1 c0 c2 c3 8b e8 74 05 ec 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:ffffc90004c8faa0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: 862f6e7b48958a00
RDX: ffffc9000c3a9000 RSI: 00000000000024b1 RDI: 00000000000024b2
RBP: 0000000000000003 R08: ffffc90004c8f7c7 R09: 1ffff92000991ef8
R10: dffffc0000000000 R11: fffff52000991ef9 R12: 000000000000000a
R13: 0000000000000008 R14: 0000000000000005 R15: 0000000000000155
FS:  00007f49cb5676c0(0000) GS:ffff888125d50000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f49cb546d58 CR3: 0000000073e56000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 dbAllocDmapLev+0x60/0x3c0 fs/jfs/jfs_dmap.c:1961
 dbAllocCtl+0x14a/0x9b0 fs/jfs/jfs_dmap.c:1817
 dbAllocAG+0xba8/0xf10 fs/jfs/jfs_dmap.c:1466
 dbDiscardAG+0x2df/0x900 fs/jfs/jfs_dmap.c:1602
 jfs_ioc_trim+0x429/0x690 fs/jfs/jfs_discard.c:106
 jfs_ioctl+0x2b5/0x3d0 fs/jfs/ioctl.c:131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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: 0033:0x7f49ca78e929
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:00007f49cb567038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f49ca9b5fa0 RCX: 00007f49ca78e929
RDX: 0000200000000000 RSI: 00000000c0185879 RDI: 0000000000000006
RBP: 00007f49ca810b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f49ca9b5fa0 R15: 00007ffdb291a308
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x51d/0x520 fs/jfs/jfs_dmap.c:2975
Code: e9 4c ff ff ff e8 73 ca 84 fe 48 c7 c7 00 b8 c3 8b 48 c7 c6 40 b5 c3 8b ba 9f 0b 00 00 48 c7 c1 c0 c2 c3 8b e8 74 05 ec 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:ffffc90004c8faa0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: 862f6e7b48958a00
RDX: ffffc9000c3a9000 RSI: 00000000000024b1 RDI: 00000000000024b2
RBP: 0000000000000003 R08: ffffc90004c8f7c7 R09: 1ffff92000991ef8
R10: dffffc0000000000 R11: fffff52000991ef9 R12: 000000000000000a
R13: 0000000000000008 R14: 0000000000000005 R15: 0000000000000155
FS:  00007f49cb5676c0(0000) GS:ffff888125d50000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f62ca7ff000 CR3: 0000000073e56000 CR4: 00000000003526f0