BUG at fs/jfs/jfs_dmap.c:2983 assert(n < 4)
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kernel BUG at fs/jfs/jfs_dmap.c:2983!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 3560 Comm: syz.6.4095 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:dbFindLeaf+0x51d/0x520
Code: e9 4c ff ff ff e8 13 8f 80 fe 48 c7 c7 c0 e6 c3 8b 48 c7 c6 00 e4 c3 8b ba a7 0b 00 00 48 c7 c1 80 f1 c3 8b e8 04 81 e8 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:ffffc90003effa98 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: 3038042636b9ba00
RDX: ffffc9000a5aa000 RSI: 000000000000144b RDI: 000000000000144c
RBP: 0000000000000003 R08: ffffc90003eff7c7 R09: 1ffff920007dfef8
R10: dffffc0000000000 R11: fffff520007dfef9 R12: 000000000000000a
R13: 0000000000000008 R14: 0000000000000005 R15: 0000000000000155
FS:  00007fc6be4f76c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ec8aa8a950 CR3: 000000001bb20000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 dbAllocDmapLev+0x60/0x3c0
 dbAllocCtl+0x14a/0x9c0
 dbAllocAG+0xc2b/0xff0
 dbDiscardAG+0x2df/0x900
 jfs_ioc_trim+0x429/0x690
 jfs_ioctl+0x2b5/0x3d0
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc6bd58ec29
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:00007fc6be4f7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fc6bd7d5fa0 RCX: 00007fc6bd58ec29
RDX: 0000200000000080 RSI: 00000000c0185879 RDI: 0000000000000004
RBP: 00007fc6bd611e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc6bd7d6038 R14: 00007fc6bd7d5fa0 R15: 00007ffd254c2df8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x51d/0x520
Code: e9 4c ff ff ff e8 13 8f 80 fe 48 c7 c7 c0 e6 c3 8b 48 c7 c6 00 e4 c3 8b ba a7 0b 00 00 48 c7 c1 80 f1 c3 8b e8 04 81 e8 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:ffffc90003effa98 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: 3038042636b9ba00
RDX: ffffc9000a5aa000 RSI: 000000000000144b RDI: 000000000000144c
RBP: 0000000000000003 R08: ffffc90003eff7c7 R09: 1ffff920007dfef8
R10: dffffc0000000000 R11: fffff520007dfef9 R12: 000000000000000a
R13: 0000000000000008 R14: 0000000000000005 R15: 0000000000000155
FS:  00007fc6be4f76c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558b0725c8 CR3: 000000001bb20000 CR4: 00000000000006f0
