loop4: detected capacity change from 0 to 32768
BUG at fs/jfs/jfs_dmap.c:3070 assert(n < 4)
------------[ cut here ]------------
kernel BUG at fs/jfs/jfs_dmap.c:3070!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 14379 Comm: syz.4.775 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:dbFindLeaf+0x519/0x520 fs/jfs/jfs_dmap.c:3070
Code: e9 4e ff ff ff e8 37 71 69 fe 48 c7 c7 e0 a0 8b 8b 48 c7 c6 20 9e 8b 8b ba fe 0b 00 00 48 c7 c1 00 ac 8b 8b e8 08 9f cb fd 90 <0f> 0b 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90004ccfab0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: 42e12cb206296900
RDX: ffffc9000e92a000 RSI: 0000000000001900 RDI: 0000000000001901
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000999f05 R12: 000000000000000a
R13: 0000000000000005 R14: 0000000000000008 R15: 0000000000000155
FS:  00007f5f742b66c0(0000) GS:ffff888126211000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f6be84000 CR3: 000000002c3fe000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 dbAllocDmapLev+0x60/0x3b0 fs/jfs/jfs_dmap.c:2056
 dbAllocCtl+0x145/0x990 fs/jfs/jfs_dmap.c:1912
 dbAllocAG+0xbbd/0xf80 fs/jfs/jfs_dmap.c:1559
 dbDiscardAG+0x2d6/0x8f0 fs/jfs/jfs_dmap.c:1695
 jfs_ioc_trim+0x433/0x670 fs/jfs/jfs_discard.c:106
 jfs_ioctl+0x291/0x3b0 fs/jfs/ioctl.c:131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f7605ce59
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:00007f5f742b6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5f762d5fa0 RCX: 00007f5f7605ce59
RDX: 0000200000000040 RSI: 00000000c0185879 RDI: 0000000000000008
RBP: 00007f5f760f2e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5f762d6038 R14: 00007f5f762d5fa0 R15: 00007ffde8344128
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x519/0x520 fs/jfs/jfs_dmap.c:3070
Code: e9 4e ff ff ff e8 37 71 69 fe 48 c7 c7 e0 a0 8b 8b 48 c7 c6 20 9e 8b 8b ba fe 0b 00 00 48 c7 c1 00 ac 8b 8b e8 08 9f cb fd 90 <0f> 0b 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90004ccfab0 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: 42e12cb206296900
RDX: ffffc9000e92a000 RSI: 0000000000001900 RDI: 0000000000001901
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000999f05 R12: 000000000000000a
R13: 0000000000000005 R14: 0000000000000008 R15: 0000000000000155
FS:  00007f5f742b66c0(0000) GS:ffff888126211000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f6be84000 CR3: 000000002c3fe000 CR4: 00000000003526f0