diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index ac4b32df42b9..d84c35f779f5 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -73,6 +73,8 @@ static void _rotate_left(struct xdr_buf *buf, unsigned int shift)
 	int shifted = 0;
 	int this_shift;
 
+	if (!buf->len)
+		return;
 	shift %= buf->len;
 	while (shifted < shift) {
 		this_shift = min(shift - shifted, LOCAL_BUF_LEN);
@@ -85,6 +87,8 @@ static void rotate_left(u32 base, struct xdr_buf *buf, unsigned int shift)
 {
 	struct xdr_buf subbuf;
 
+	if (buf->len <= base)
+		return;
 	xdr_buf_subsegment(buf, &subbuf, base, buf->len - base);
 	_rotate_left(&subbuf, shift);
 }
@@ -154,6 +158,9 @@ gss_krb5_unwrap_v2(struct krb5_ctx *kctx, int offset, int len,
 
 	dprintk("RPC:       %s\n", __func__);
 
+	if (len - offset <= GSS_KRB5_TOK_HDR_LEN)
+		return GSS_S_DEFECTIVE_TOKEN;
+
 	ptr = buf->head[0].iov_base + offset;
 
 	if (be16_to_cpu(*((__be16 *)ptr)) != KG2_TOK_WRAP)
@@ -220,9 +227,9 @@ gss_krb5_unwrap_v2(struct krb5_ctx *kctx, int offset, int len,
 	 * head buffer space rather than that actually occupied.
 	 */
 	movelen = min_t(unsigned int, buf->head[0].iov_len, len);
+	if (movelen < offset + GSS_KRB5_TOK_HDR_LEN + headskip)
+		return GSS_S_DEFECTIVE_TOKEN;
 	movelen -= offset + GSS_KRB5_TOK_HDR_LEN + headskip;
-	BUG_ON(offset + GSS_KRB5_TOK_HDR_LEN + headskip + movelen >
-							buf->head[0].iov_len);
 	memmove(ptr, ptr + GSS_KRB5_TOK_HDR_LEN + headskip, movelen);
 	buf->head[0].iov_len -= GSS_KRB5_TOK_HDR_LEN + headskip;
 	buf->len = len - (GSS_KRB5_TOK_HDR_LEN + headskip);