BUG at fs/jfs/jfs_dmap.c:3036 assert(bitno < 32)
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kernel BUG at fs/jfs/jfs_dmap.c:3036!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5386 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:dbFindBits+0x19e/0x1a0 fs/jfs/jfs_dmap.c:3036
Code: e1 fd 90 0f 0b e8 82 8d 7a fe 48 c7 c7 00 7e a4 8b 48 c7 c6 40 7b a4 8b ba dc 0b 00 00 48 c7 c1 e0 85 a4 8b e8 d3 fb e1 fd 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41
RSP: 0018:ffffc9000d3a7190 EFLAGS: 00010246
RAX: 0000000000000030 RBX: 0000000000000000 RCX: 58ec0a899cfada00
RDX: ffffc9000e5c3000 RSI: 0000000000000662 RDI: 0000000000000663
RBP: 00000000ffffffff R08: ffffc9000d3a6ea7 R09: 1ffff92001a74dd4
R10: dffffc0000000000 R11: fffff52001a74dd5 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000020
FS:  00007f7789fec6c0(0000) GS:ffff88808d730000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 000000004411d000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 dbAllocNear+0x244/0x3d0 fs/jfs/jfs_dmap.c:1243
 dbAlloc+0x933/0xba0 fs/jfs/jfs_dmap.c:832
 extBalloc fs/jfs/jfs_extent.c:336 [inline]
 extAlloc+0x54a/0xfb0 fs/jfs/jfs_extent.c:127
 jfs_get_block+0x346/0xab0 fs/jfs/inode.c:254
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145
 block_write_begin+0x8a/0x120 fs/buffer.c:2256
 jfs_write_begin+0x35/0x80 fs/jfs/inode.c:306
 generic_perform_write+0x2c5/0x900 mm/filemap.c:4242
 generic_file_write_iter+0x117/0x550 mm/filemap.c:4385
 do_iter_readv_writev+0x623/0x8c0 fs/read_write.c:-1
 vfs_writev+0x31a/0x960 fs/read_write.c:1057
 do_writev+0x14d/0x2d0 fs/read_write.c:1103
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f778918f6c9
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:00007f7789fec038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f77893e6090 RCX: 00007f778918f6c9
RDX: 0000000000000001 RSI: 00002000000002c0 RDI: 0000000000000006
RBP: 00007f7789211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f77893e6128 R14: 00007f77893e6090 R15: 00007ffc22f1c238
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindBits+0x19e/0x1a0 fs/jfs/jfs_dmap.c:3036
Code: e1 fd 90 0f 0b e8 82 8d 7a fe 48 c7 c7 00 7e a4 8b 48 c7 c6 40 7b a4 8b ba dc 0b 00 00 48 c7 c1 e0 85 a4 8b e8 d3 fb e1 fd 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41
RSP: 0018:ffffc9000d3a7190 EFLAGS: 00010246
RAX: 0000000000000030 RBX: 0000000000000000 RCX: 58ec0a899cfada00
RDX: ffffc9000e5c3000 RSI: 0000000000000662 RDI: 0000000000000663
RBP: 00000000ffffffff R08: ffffc9000d3a6ea7 R09: 1ffff92001a74dd4
R10: dffffc0000000000 R11: fffff52001a74dd5 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000020
FS:  00007f7789fec6c0(0000) GS:ffff88808d730000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 000000004411d000 CR4: 0000000000352ef0