net: Make setsockopt() optlen be unsigned.

This provides safety against negative optlen at the type
level instead of depending upon (sometimes non-trivial)
checks against this sprinkled all over the the place, in
each and every implementation.

Based upon work done by Arjan van de Ven and feedback
from Linus Torvalds.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/atmdev.h b/include/linux/atmdev.h
index 086e5c3..817b237 100644
--- a/include/linux/atmdev.h
+++ b/include/linux/atmdev.h
@@ -397,7 +397,7 @@
 	int (*getsockopt)(struct atm_vcc *vcc,int level,int optname,
 	    void __user *optval,int optlen);
 	int (*setsockopt)(struct atm_vcc *vcc,int level,int optname,
-	    void __user *optval,int optlen);
+	    void __user *optval,unsigned int optlen);
 	int (*send)(struct atm_vcc *vcc,struct sk_buff *skb);
 	int (*send_oam)(struct atm_vcc *vcc,void *cell,int flags);
 	void (*phy_put)(struct atm_dev *dev,unsigned char value,
diff --git a/include/linux/mroute.h b/include/linux/mroute.h
index 0d45b4e..08bc776 100644
--- a/include/linux/mroute.h
+++ b/include/linux/mroute.h
@@ -145,14 +145,14 @@
 #endif
 
 #ifdef CONFIG_IP_MROUTE
-extern int ip_mroute_setsockopt(struct sock *, int, char __user *, int);
+extern int ip_mroute_setsockopt(struct sock *, int, char __user *, unsigned int);
 extern int ip_mroute_getsockopt(struct sock *, int, char __user *, int __user *);
 extern int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg);
 extern int ip_mr_init(void);
 #else
 static inline
 int ip_mroute_setsockopt(struct sock *sock,
-			 int optname, char __user *optval, int optlen)
+			 int optname, char __user *optval, unsigned int optlen)
 {
 	return -ENOPROTOOPT;
 }
diff --git a/include/linux/mroute6.h b/include/linux/mroute6.h
index 43dc97e..b191865 100644
--- a/include/linux/mroute6.h
+++ b/include/linux/mroute6.h
@@ -134,7 +134,7 @@
 struct sock;
 
 #ifdef CONFIG_IPV6_MROUTE
-extern int ip6_mroute_setsockopt(struct sock *, int, char __user *, int);
+extern int ip6_mroute_setsockopt(struct sock *, int, char __user *, unsigned int);
 extern int ip6_mroute_getsockopt(struct sock *, int, char __user *, int __user *);
 extern int ip6_mr_input(struct sk_buff *skb);
 extern int ip6mr_ioctl(struct sock *sk, int cmd, void __user *arg);
@@ -143,7 +143,7 @@
 #else
 static inline
 int ip6_mroute_setsockopt(struct sock *sock,
-			  int optname, char __user *optval, int optlen)
+			  int optname, char __user *optval, unsigned int optlen)
 {
 	return -ENOPROTOOPT;
 }
diff --git a/include/linux/net.h b/include/linux/net.h
index 9040a10..529a093 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -178,11 +178,11 @@
 	int		(*listen)    (struct socket *sock, int len);
 	int		(*shutdown)  (struct socket *sock, int flags);
 	int		(*setsockopt)(struct socket *sock, int level,
-				      int optname, char __user *optval, int optlen);
+				      int optname, char __user *optval, unsigned int optlen);
 	int		(*getsockopt)(struct socket *sock, int level,
 				      int optname, char __user *optval, int __user *optlen);
 	int		(*compat_setsockopt)(struct socket *sock, int level,
-				      int optname, char __user *optval, int optlen);
+				      int optname, char __user *optval, unsigned int optlen);
 	int		(*compat_getsockopt)(struct socket *sock, int level,
 				      int optname, char __user *optval, int __user *optlen);
 	int		(*sendmsg)   (struct kiocb *iocb, struct socket *sock,
@@ -256,7 +256,7 @@
 extern int kernel_getsockopt(struct socket *sock, int level, int optname,
 			     char *optval, int *optlen);
 extern int kernel_setsockopt(struct socket *sock, int level, int optname,
-			     char *optval, int optlen);
+			     char *optval, unsigned int optlen);
 extern int kernel_sendpage(struct socket *sock, struct page *page, int offset,
 			   size_t size, int flags);
 extern int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg);
@@ -313,7 +313,7 @@
 SOCKCALL_WRAP(name, listen, (struct socket *sock, int len), (sock, len)) \
 SOCKCALL_WRAP(name, shutdown, (struct socket *sock, int flags), (sock, flags)) \
 SOCKCALL_WRAP(name, setsockopt, (struct socket *sock, int level, int optname, \
-			 char __user *optval, int optlen), (sock, level, optname, optval, optlen)) \
+			 char __user *optval, unsigned int optlen), (sock, level, optname, optval, optlen)) \
 SOCKCALL_WRAP(name, getsockopt, (struct socket *sock, int level, int optname, \
 			 char __user *optval, int __user *optlen), (sock, level, optname, optval, optlen)) \
 SOCKCALL_WRAP(name, sendmsg, (struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t len), \
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index 48cfe51..6132b5e 100644
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -221,12 +221,12 @@
 
 /* Call setsockopt() */
 int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
-		  int len);
+		  unsigned int len);
 int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
 		  int *len);
 
 int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
-		char __user *opt, int len);
+		char __user *opt, unsigned int len);
 int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
 		char __user *opt, int *len);