Out-of-bounds write in nix::unistd::getgrouplist
On certain platforms, if a user has more than 16 groups, the nix::unistd::getgrouplist function will call the libc getgrouplist function with a length parameter greater than the size of the buffer it provides, resulting in an out-of-bounds write and memory corruption. The libc getgrouplist function takes an in/out parameter ngroups specifying the size of the group buffer. When the buffer is too small to hold all of the reqested user's …