NFSD: Replace READ* macros in nfsd4_decode_commit()

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/nfsd/nfs4xdr.c

@@ -581,13 +581,11 @@ nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
 static __be32
 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
 {
-	DECODE_HEAD;
-
-	READ_BUF(12);
-	p = xdr_decode_hyper(p, &commit->co_offset);
-	commit->co_count = be32_to_cpup(p++);
-
-	DECODE_TAIL;
+	if (xdr_stream_decode_u64(argp->xdr, &commit->co_offset) < 0)
+		return nfserr_bad_xdr;
+	if (xdr_stream_decode_u32(argp->xdr, &commit->co_count) < 0)
+		return nfserr_bad_xdr;
+	return nfs_ok;
 }
 
 static __be32

include/linux/sunrpc/xdr.h

@@ -571,6 +571,27 @@ xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr)
 	return 0;
 }
 
+/**
+ * xdr_stream_decode_u64 - Decode a 64-bit integer
+ * @xdr: pointer to xdr_stream
+ * @ptr: location to store 64-bit integer
+ *
+ * Return values:
+ *   %0 on success
+ *   %-EBADMSG on XDR buffer overflow
+ */
+static inline ssize_t
+xdr_stream_decode_u64(struct xdr_stream *xdr, __u64 *ptr)
+{
+	const size_t count = sizeof(*ptr);
+	__be32 *p = xdr_inline_decode(xdr, count);
+
+	if (unlikely(!p))
+		return -EBADMSG;
+	xdr_decode_hyper(p, ptr);
+	return 0;
+}
+
 /**
  * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
  * @xdr: pointer to xdr_stream