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: 0 UID: 0 PID: 7656 Comm: syz.7.243 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 d3 8d 74 fe 48 c7 c7 20 55 c5 8b 48 c7 c6 60 52 c5 8b ba a7 0b 00 00 48 c7 c1 00 60 c5 8b e8 44 b0 d9 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:ffffc90007277aa0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: fe5425caaefc4d00
RDX: ffffc90004c89000 RSI: 0000000000000eb4 RDI: 0000000000000eb5
RBP: 0000000000000003 R08: ffffc90007277827 R09: 1ffff92000e4ef04
R10: dffffc0000000000 R11: fffff52000e4ef05 R12: 000000000000000a
R13: 0000000000000008 R14: 0000000000000005 R15: 0000000000000155
FS:  00007fd5a00606c0(0000) GS:ffff88818e40b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32410ff8 CR3: 0000000112292000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 dbAllocDmapLev+0x60/0x3c0
 dbAllocCtl+0x14a/0x9c0
 dbAllocAG+0xc2b/0xff0
 dbDiscardAG+0x2da/0x8f0
 jfs_ioc_trim+0x429/0x690
 jfs_ioctl+0x28e/0x3b0
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd59f19acb9
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:00007fd5a0060028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd59f415fa0 RCX: 00007fd59f19acb9
RDX: 0000200000000080 RSI: 00000000c0185879 RDI: 0000000000000008
RBP: 00007fd59f208bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd59f416038 R14: 00007fd59f415fa0 R15: 00007ffce02f3248
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x51d/0x520
Code: e9 4c ff ff ff e8 d3 8d 74 fe 48 c7 c7 20 55 c5 8b 48 c7 c6 60 52 c5 8b ba a7 0b 00 00 48 c7 c1 00 60 c5 8b e8 44 b0 d9 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:ffffc90007277aa0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: fe5425caaefc4d00
RDX: ffffc90004c89000 RSI: 0000000000000eb4 RDI: 0000000000000eb5
RBP: 0000000000000003 R08: ffffc90007277827 R09: 1ffff92000e4ef04
R10: dffffc0000000000 R11: fffff52000e4ef05 R12: 000000000000000a
R13: 0000000000000008 R14: 0000000000000005 R15: 0000000000000155
FS:  00007fd5a00606c0(0000) GS:ffff88818e40b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f03fed84900 CR3: 0000000112292000 CR4: 00000000000006f0
