>>>>panic: malloc: allocation too large, type = 2, size = 18446744073709550816

Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
  88323     43      0           0          0    1  syz-executor.1
*444790     43      0           0  0x4000000    0K 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(fffffffffffffce0,2,a) at malloc+0x9c9 sys/kern/kern_malloc.c:344
vm_get_info(ffff800021b77520) at vm_get_info+0x9d
VOP_IOCTL(fffffd806e2ad9c0,c0185603,ffff800021b77520,1,fffffd807f7c6660,ffff800020ace788) at VOP_IOCTL+0x88 sys/kern/vfs_vops.c:291
vn_ioctl(fffffd807adf8be0,c0185603,ffff800021b77520,ffff800020ace788) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:524
sys_ioctl(ffff800020ace788,ffff800021b77638,ffff800021b77680) at sys_ioctl+0x5b9
syscall(ffff800021b77700) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800021b77700) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff53,0,3,50c3413e010) at Xsyscall+0x128
end of kernel
end trace frame: 0x50f1f890e40, count: 6
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