if returning errno value directly from a syscall, we need to negate it.

[musl] / src / unistd / lchown.c

#include <unistd.h>
#include "syscall.h"

int lchown(const char *path, uid_t uid, gid_t gid)
{
        return syscall3(__NR_lchown, (long)path, uid, gid);
}