BUG at fs/jfs/jfs_dmap.c:2983 assert(n < 4)
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kernel BUG at fs/jfs/jfs_dmap.c:2983!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 6890 Comm: syz.4.374 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:2983
Code: fe e9 51 ff ff ff e8 18 fe 95 fe 48 c7 c7 20 f9 c5 8a 48 c7 c6 a0 f6 c5 8a ba a7 0b 00 00 48 c7 c1 40 04 c6 8a e8 49 ed 21 07 <0f> 0b 0f 1f 80 00 00 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec
RSP: 0000:ffffc90003e97ac0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 54c4c41b95e3c700
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffff520007d2ef9
R10: fffff520007d2ef9 R11: 1ffff920007d2ef8 R12: 0000000000000008
R13: 0000000000000060 R14: 000000000000005d R15: 0000000000000155
FS:  00007f76cbad16c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f76c0bda000 CR3: 000000002459e000 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:1969
 dbAllocCtl+0x148/0x9b0 fs/jfs/jfs_dmap.c:1825
 dbAllocAG+0x1e7/0xfe0 fs/jfs/jfs_dmap.c:1353
 dbDiscardAG+0x2ca/0x8e0 fs/jfs/jfs_dmap.c:1608
 jfs_ioc_trim+0x42b/0x660 fs/jfs/jfs_discard.c:105
 jfs_ioctl+0x2b6/0x3d0 fs/jfs/ioctl.c:131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f76cab8f749
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:00007f76cbad1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f76cade6090 RCX: 00007f76cab8f749
RDX: 0000200000000680 RSI: 00000000c0185879 RDI: 0000000000000005
RBP: 00007f76cac13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f76cade6128 R14: 00007f76cade6090 R15: 00007ffcdc40bd28
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x517/0x520 fs/jfs/jfs_dmap.c:2983
Code: fe e9 51 ff ff ff e8 18 fe 95 fe 48 c7 c7 20 f9 c5 8a 48 c7 c6 a0 f6 c5 8a ba a7 0b 00 00 48 c7 c1 40 04 c6 8a e8 49 ed 21 07 <0f> 0b 0f 1f 80 00 00 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec
RSP: 0000:ffffc90003e97ac0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 00000000ffffffff RCX: 54c4c41b95e3c700
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffff520007d2ef9
R10: fffff520007d2ef9 R11: 1ffff920007d2ef8 R12: 0000000000000008
R13: 0000000000000060 R14: 000000000000005d R15: 0000000000000155
FS:  00007f76cbad16c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055639d36e950 CR3: 000000002459e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400