panic: malloc: allocation too large, type = 2, size = 18446744073709551296

Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 357637  90741      0           0          0    0  syz-executor.0
*135288  90741      0           0  0x4000000    1K syz-executor.0
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
malloc(fffffffffffffec0,2,a) at malloc+0x9c9 sys/kern/kern_malloc.c:344
vm_get_info(ffff80002359b0d0) at vm_get_info+0x9d
VOP_IOCTL(fffffd806ec0d750,c0185603,ffff80002359b0d0,1,fffffd807f7c6a20,ffff800020ab0290) at VOP_IOCTL+0x88 sys/kern/vfs_vops.c:291
vn_ioctl(fffffd8066b79008,c0185603,ffff80002359b0d0,ffff800020ab0290) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:524
sys_ioctl(ffff800020ab0290,ffff80002359b1e8,ffff80002359b230) at sys_ioctl+0x5b9
syscall(ffff80002359b2b0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff80002359b2b0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff53,0,3,b66a2c0c0e0) at Xsyscall+0x128
end of kernel
end trace frame: 0xb68a32fd8c0, count: 6
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