BUG at fs/jfs/jfs_dmap.c:3051 assert(n < 4)
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kernel BUG at fs/jfs/jfs_dmap.c:3051!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 7261 Comm: syz.6.529 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:dbFindLeaf+0x517/0x520 fs/jfs/jfs_dmap.c:3051
Code: fe e9 51 ff ff ff e8 b8 d7 a9 fe 48 c7 c7 40 29 62 8a 48 c7 c6 c0 26 62 8a ba eb 0b 00 00 48 c7 c1 40 34 62 8a e8 c9 f9 e1 06 <0f> 0b 0f 1f 80 00 00 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec
RSP: 0018:ffffc9000356ed98 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 4047fc40544b4200
RDX: ffffc9000f039000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: 0000000000000001 R08: ffff8880b9133d7f R09: 1ffff110172267af
R10: dffffc0000000000 R11: ffffed10172267b0 R12: 0000000000000004
R13: 00000000000000d0 R14: 00000000000000cd R15: 0000000000000155
FS:  00007f1a0a0676c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f12d140edac CR3: 0000000068b8f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 dbAllocDmapLev+0x61/0x3c0 fs/jfs/jfs_dmap.c:2037
 dbAlloc+0x98b/0xba0 fs/jfs/jfs_dmap.c:844
 extBalloc fs/jfs/jfs_extent.c:523 [inline]
 extAlloc+0x4fc/0xf80 fs/jfs/jfs_extent.c:125
 jfs_get_block+0x355/0xad0 fs/jfs/inode.c:264
 get_more_blocks fs/direct-io.c:673 [inline]
 do_direct_IO fs/direct-io.c:959 [inline]
 do_blockdev_direct_IO fs/direct-io.c:1276 [inline]
 __blockdev_direct_IO+0x13d4/0x3a70 fs/direct-io.c:1368
 blockdev_direct_IO include/linux/fs.h:3345 [inline]
 jfs_direct_IO+0x119/0x220 fs/jfs/inode.c:349
 generic_file_direct_write+0x22c/0x490 mm/filemap.c:3687
 __generic_file_write_iter+0x2b1/0x4e0 mm/filemap.c:3869
 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944
 do_iter_readv_writev+0x47e/0x5f0 fs/read_write.c:-1
 do_iter_write+0x205/0x7b0 fs/read_write.c:855
 iter_file_splice_write+0x699/0xcc0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0xe1/0x130 fs/splice.c:956
 splice_direct_to_actor+0x4ea/0xc10 fs/splice.c:902
 do_splice_direct+0x1d4/0x2f0 fs/splice.c:1008
 do_sendfile+0x5fc/0xeb0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1303
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1a0be2ceb9
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:00007f1a0a067028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f1a0c0a8090 RCX: 00007f1a0be2ceb9
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000008
RBP: 00007f1a0be9ac1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020fffe81 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a0c0a8128 R14: 00007f1a0c0a8090 R15: 00007ffe024c9ab8
 </TASK>
Modules linked in:
---[ end trace 36fa5ccf1978e3c3 ]---
RIP: 0010:dbFindLeaf+0x517/0x520 fs/jfs/jfs_dmap.c:3051
Code: fe e9 51 ff ff ff e8 b8 d7 a9 fe 48 c7 c7 40 29 62 8a 48 c7 c6 c0 26 62 8a ba eb 0b 00 00 48 c7 c1 40 34 62 8a e8 c9 f9 e1 06 <0f> 0b 0f 1f 80 00 00 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec
RSP: 0018:ffffc9000356ed98 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 4047fc40544b4200
RDX: ffffc9000f039000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: 0000000000000001 R08: ffff8880b9133d7f R09: 1ffff110172267af
R10: dffffc0000000000 R11: ffffed10172267b0 R12: 0000000000000004
R13: 00000000000000d0 R14: 00000000000000cd R15: 0000000000000155
FS:  00007f1a0a0676c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f12d140edac CR3: 0000000068b8f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400