fou: fix some member types in guehdr

guehdr struct is used to build or parse gue packets, which
are always in big endian. It's better to define all guehdr
members as __beXX types.

Also, in validate_gue_flags it's not good to use a __be32
variable for both Standard flags(__be16) and Private flags
(__be32), and pass it to other funcions.

This patch could fix a bunch of sparse warnings from fou.

Fixes: 5024c33a ("gue: Add infrastructure for flags and options")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/gue.h

@@ -45,9 +45,9 @@ struct guehdr {
 #error  "Please fix <asm/byteorder.h>"
 #endif
 			__u8	proto_ctype;
-			__u16   flags;
+			__be16	flags;
 		};
-		__u32 word;
+		__be32	word;
 	};
 };
 
@@ -84,11 +84,10 @@ static inline size_t guehdr_priv_flags_len(__be32 flags)
  * if there is an unknown standard or private flags, or the options length for
  * the flags exceeds the options length specific in hlen of the GUE header.
  */
-static inline int validate_gue_flags(struct guehdr *guehdr,
-				     size_t optlen)
+static inline int validate_gue_flags(struct guehdr *guehdr, size_t optlen)
 {
+	__be16 flags = guehdr->flags;
 	size_t len;
-	__be32 flags = guehdr->flags;
 
 	if (flags & ~GUE_FLAGS_ALL)
 		return 1;
@@ -101,12 +100,13 @@ static inline int validate_gue_flags(struct guehdr *guehdr,
 		/* Private flags are last four bytes accounted in
 		 * guehdr_flags_len
 		 */
-		flags = *(__be32 *)((void *)&guehdr[1] + len - GUE_LEN_PRIV);
+		__be32 pflags = *(__be32 *)((void *)&guehdr[1] +
+					    len - GUE_LEN_PRIV);
 
-		if (flags & ~GUE_PFLAGS_ALL)
+		if (pflags & ~GUE_PFLAGS_ALL)
 			return 1;
 
-		len += guehdr_priv_flags_len(flags);
+		len += guehdr_priv_flags_len(pflags);
 		if (len > optlen)
 			return 1;
 	}