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

Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*193756  47070      0           0  0x4000000    0  syz-executor.1
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(ffff8000159443c0) at vm_get_info+0x9a
VOP_IOCTL(fffffd80365688f0,c0185603,ffff8000159443c0,1,fffffd803f7c6a20,ffff800015953650) at VOP_IOCTL+0x88 sys/kern/vfs_vops.c:291
vn_ioctl(fffffd803ceb5ad0,c0185603,ffff8000159443c0,ffff800015953650) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:524
sys_ioctl(ffff800015953650,ffff8000159444d8,ffff800015944520) at sys_ioctl+0x5b9
syscall(ffff8000159445a0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff53,0,3,95c4a6a2010) at Xsyscall+0x128
end of kernel
end trace frame: 0x95ef68a75c0, count: 6
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