const struct sock_filter *filter);
extern int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
extern int sk_detach_filter(struct sock *sk);
-extern int sk_chk_filter(struct sock_filter *filter, int flen);
+extern int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
#ifdef CONFIG_BPF_JIT
extern void bpf_jit_compile(struct sk_filter *fp);