diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index d84c35f779f5..d3f61c4b5a13 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -235,6 +235,8 @@ gss_krb5_unwrap_v2(struct krb5_ctx *kctx, int offset, int len,
 	buf->len = len - (GSS_KRB5_TOK_HDR_LEN + headskip);
 
 	/* Trim off the trailing "extra count" and checksum blob */
+	if (ec + GSS_KRB5_TOK_HDR_LEN + tailskip > buf->len - offset)
+		return GSS_S_DEFECTIVE_TOKEN;
 	xdr_buf_trim(buf, ec + GSS_KRB5_TOK_HDR_LEN + tailskip);
 
 	*align = XDR_QUADLEN(GSS_KRB5_TOK_HDR_LEN + headskip);