BUG at fs/jfs/jfs_dmap.c:3070 assert(n < 4)
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kernel BUG at fs/jfs/jfs_dmap.c:3070!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5570 Comm: syz.0.17 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:dbFindLeaf+0x519/0x520 fs/jfs/jfs_dmap.c:3070
Code: e9 4e ff ff ff e8 a7 82 49 fe 48 c7 c7 20 9b 6e 8c 48 c7 c6 60 98 6e 8c ba fe 0b 00 00 48 c7 c1 40 a6 6e 8c e8 28 13 a8 fd 90 <0f> 0b 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90001df71e0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 3be1ea887ce96b00
RDX: 0000000000000000 RSI: 8000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffc90001df6f67 R09: 1ffff920003bedec
R10: dffffc0000000000 R11: fffff520003beded R12: 0000000000000007
R13: 000000000000005d R14: 0000000000000060 R15: 0000000000000155
FS:  00005555916bd500(0000) GS:ffff88808a9f9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fce25d05a10 CR3: 0000000045c38000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 dbAllocDmapLev+0x60/0x3b0 fs/jfs/jfs_dmap.c:2056
 dbAlloc+0x993/0xba0 fs/jfs/jfs_dmap.c:931
 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
 get_more_blocks fs/direct-io.c:644 [inline]
 do_direct_IO fs/direct-io.c:932 [inline]
 __blockdev_direct_IO+0x1590/0x3380 fs/direct-io.c:1236
 blockdev_direct_IO include/linux/fs.h:3164 [inline]
 jfs_direct_IO+0x119/0x220 fs/jfs/inode.c:339
 generic_file_direct_write+0x1d0/0x3f0 mm/filemap.c:4326
 __generic_file_write_iter+0x11d/0x230 mm/filemap.c:4495
 generic_file_write_iter+0xae/0x330 mm/filemap.c:4535
 do_iter_readv_writev+0x612/0x8c0 fs/read_write.c:-1
 vfs_writev+0x343/0x990 fs/read_write.c:1058
 do_pwritev+0x1a9/0x2d0 fs/read_write.c:1153
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x16a/0x530 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f45565a8f19
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:00007ffd27c6b618 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f4556825fa0 RCX: 00007f45565a8f19
RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000004
RBP: 00007f4556637f6d R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000002000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4556825fac R14: 00007f4556825fa0 R15: 00007f4556825fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x519/0x520 fs/jfs/jfs_dmap.c:3070
Code: e9 4e ff ff ff e8 a7 82 49 fe 48 c7 c7 20 9b 6e 8c 48 c7 c6 60 98 6e 8c ba fe 0b 00 00 48 c7 c1 40 a6 6e 8c e8 28 13 a8 fd 90 <0f> 0b 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90001df71e0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 3be1ea887ce96b00
RDX: 0000000000000000 RSI: 8000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffc90001df6f67 R09: 1ffff920003bedec
R10: dffffc0000000000 R11: fffff520003beded R12: 0000000000000007
R13: 000000000000005d R14: 0000000000000060 R15: 0000000000000155
FS:  00005555916bd500(0000) GS:ffff88808a9f9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0ff25f6c50 CR3: 0000000045c38000 CR4: 0000000000352ef0