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: 0 PID: 16466 Comm: syz.6.1928 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:dbFindLeaf+0x513/0x520 fs/jfs/jfs_dmap.c:2983
Code: fe e9 53 ff ff ff e8 9c 67 83 fe 48 c7 c7 60 ca 03 8b 48 c7 c6 a0 c7 03 8b ba a7 0b 00 00 48 c7 c1 40 d5 03 8b e8 8d c5 7c 07 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 55 41 57 41 56 41 55 41 54
RSP: 0018:ffffc90004ab7ac8 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: 59c26fb7cffcb000
RDX: ffffc90016077000 RSI: 0000000000004471 RDI: 0000000000004472
RBP: 0000000000000003 R08: ffffc90004ab77c7 R09: 1ffff92000956ef8
R10: dffffc0000000000 R11: fffff52000956ef9 R12: 000000000000000a
R13: 0000000000000005 R14: 0000000000000008 R15: 0000000000000155
FS:  00007fe026a9e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe025beb540 CR3: 0000000067c28000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 dbAllocDmapLev+0x61/0x3b0 fs/jfs/jfs_dmap.c:1969
 dbAllocCtl+0x143/0x980 fs/jfs/jfs_dmap.c:1825
 dbAllocAG+0xc46/0x1000 fs/jfs/jfs_dmap.c:1472
 dbDiscardAG+0x2c5/0x8e0 fs/jfs/jfs_dmap.c:1608
 jfs_ioc_trim+0x44e/0x6c0 fs/jfs/jfs_discard.c:105
 jfs_ioctl+0x292/0x3b0 fs/jfs/ioctl.c:131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe025b9de59
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:00007fe026a9e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe025e25fa0 RCX: 00007fe025b9de59
RDX: 0000200000000080 RSI: 00000000c0185879 RDI: 0000000000000008
RBP: 00007fe025c33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe025e26038 R14: 00007fe025e25fa0 R15: 00007ffda2ef55a8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x513/0x520 fs/jfs/jfs_dmap.c:2983
Code: fe e9 53 ff ff ff e8 9c 67 83 fe 48 c7 c7 60 ca 03 8b 48 c7 c6 a0 c7 03 8b ba a7 0b 00 00 48 c7 c1 40 d5 03 8b e8 8d c5 7c 07 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 55 41 57 41 56 41 55 41 54
RSP: 0018:ffffc90004ab7ac8 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: 59c26fb7cffcb000
RDX: ffffc90016077000 RSI: 0000000000004471 RDI: 0000000000004472
RBP: 0000000000000003 R08: ffffc90004ab77c7 R09: 1ffff92000956ef8
R10: dffffc0000000000 R11: fffff52000956ef9 R12: 000000000000000a
R13: 0000000000000005 R14: 0000000000000008 R15: 0000000000000155
FS:  00007fe026a9e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3381eff8 CR3: 0000000067c28000 CR4: 00000000003506f0