BUG at fs/jfs/jfs_dmap.c:2972 assert(n < 4)
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kernel BUG at fs/jfs/jfs_dmap.c:2972!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 5095 Comm: syz-executor.0 Not tainted 6.7.0-rc5-syzkaller-00047-g5bd7ef53ffe5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:dbFindLeaf+0x4df/0x4f0 fs/jfs/jfs_dmap.c:2972
Code: e9 55 ff ff ff e8 81 15 7c fe 48 c7 c7 20 43 a2 8b 48 c7 c6 60 40 a2 8b ba 9c 0b 00 00 48 c7 c1 e0 4d a2 8b e8 02 3b 02 08 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 41 57 41 56
RSP: 0018:ffffc90003cbf118 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 0d23d6631974f800
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000011 R08: ffffffff81713a3c R09: 1ffff92000797dc4
R10: dffffc0000000000 R11: fffff52000797dc5 R12: 0000000000000155
R13: 0000000000000003 R14: 0000000000000014 R15: 0000000000000000
FS:  00007f450ffa76c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020da1000 CR3: 000000002115b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 dbAllocDmapLev+0xd3/0x490 fs/jfs/jfs_dmap.c:1967
 dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1823
 dbAllocAG+0x28f/0x10b0 fs/jfs/jfs_dmap.c:1364
 dbAlloc+0x658/0xca0 fs/jfs/jfs_dmap.c:888
 extBalloc fs/jfs/jfs_extent.c:326 [inline]
 extAlloc+0x4f8/0x1000 fs/jfs/jfs_extent.c:122
 jfs_get_block+0x41b/0xe60 fs/jfs/inode.c:248
 __block_write_begin_int+0x54d/0x1ad0 fs/buffer.c:2119
 __block_write_begin fs/buffer.c:2168 [inline]
 block_write_begin+0x9b/0x1e0 fs/buffer.c:2227
 jfs_write_begin+0x31/0x70 fs/jfs/inode.c:299
 generic_perform_write+0x31b/0x630 mm/filemap.c:3918
 generic_file_write_iter+0xaf/0x310 mm/filemap.c:4039
 do_iter_readv_writev+0x330/0x4a0
 do_iter_write+0x1f6/0x8d0 fs/read_write.c:860
 vfs_writev fs/read_write.c:933 [inline]
 do_pwritev+0x21a/0x360 fs/read_write.c:1030
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f450f27cba9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f450ffa70c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f450f39bf80 RCX: 00007f450f27cba9
RDX: 0000000000000001 RSI: 0000000020000100 RDI: 0000000000000004
RBP: 00007f450f2c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000005405 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f450f39bf80 R15: 00007ffd62975808
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x4df/0x4f0 fs/jfs/jfs_dmap.c:2972
Code: e9 55 ff ff ff e8 81 15 7c fe 48 c7 c7 20 43 a2 8b 48 c7 c6 60 40 a2 8b ba 9c 0b 00 00 48 c7 c1 e0 4d a2 8b e8 02 3b 02 08 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 41 57 41 56
RSP: 0018:ffffc90003cbf118 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 0d23d6631974f800
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000011 R08: ffffffff81713a3c R09: 1ffff92000797dc4
R10: dffffc0000000000 R11: fffff52000797dc5 R12: 0000000000000155
R13: 0000000000000003 R14: 0000000000000014 R15: 0000000000000000
FS:  00007f450ffa76c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020da1000 CR3: 000000002115b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400