panic: malloc: allocation too large, type = 2, size = 18446744073709550976

Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*304772  38187      0           0  0x4000000    0  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(fffffffffffffd80,2,a) at malloc+0x9c9 sys/kern/kern_malloc.c:344
vm_get_info(ffff800016b227d0) at vm_get_info+0x9a
VOP_IOCTL(fffffd803a79f8f0,c0185603,ffff800016b227d0,81,fffffd803f7c6960,ffff8000ffff8280) at VOP_IOCTL+0x88 sys/kern/vfs_vops.c:291
vn_ioctl(fffffd802e97f360,c0185603,ffff800016b227d0,ffff8000ffff8280) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:524
sys_ioctl(ffff8000ffff8280,ffff800016b228e8,ffff800016b22930) at sys_ioctl+0x5b9
syscall(ffff800016b229b0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff53,0,3,5e4568b1010) at Xsyscall+0x128
end of kernel
end trace frame: 0x5e6e3423340, count: 6
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