From patchwork Wed Dec 9 14:47:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 11961671 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1DA7C433FE for ; Wed, 9 Dec 2020 14:49:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6E82F233EA for ; Wed, 9 Dec 2020 14:49:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733075AbgLIOsy (ORCPT ); Wed, 9 Dec 2020 09:48:54 -0500 Received: from mail.kernel.org ([198.145.29.99]:49204 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733219AbgLIOsr (ORCPT ); Wed, 9 Dec 2020 09:48:47 -0500 From: trondmy@kernel.org Authentication-Results: mail.kernel.org; dkim=permerror (bad message/signature format) To: linux-nfs@vger.kernel.org Subject: [PATCH 01/16] SUNRPC: _shift_data_left/right_pages should check the shift length Date: Wed, 9 Dec 2020 09:47:46 -0500 Message-Id: <20201209144801.700778-2-trondmy@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201209144801.700778-1-trondmy@kernel.org> References: <20201209144801.700778-1-trondmy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Trond Myklebust Exit early if the shift is zero. Signed-off-by: Trond Myklebust --- net/sunrpc/xdr.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c index f9efc207a7d5..1d48934bdf9e 100644 --- a/net/sunrpc/xdr.c +++ b/net/sunrpc/xdr.c @@ -226,6 +226,9 @@ _shift_data_left_pages(struct page **pages, size_t pgto_base, BUG_ON(pgfrom_base <= pgto_base); + if (!len) + return; + pgto = pages + (pgto_base >> PAGE_SHIFT); pgfrom = pages + (pgfrom_base >> PAGE_SHIFT); @@ -308,6 +311,9 @@ _shift_data_right_pages(struct page **pages, size_t pgto_base, BUG_ON(pgto_base <= pgfrom_base); + if (!len) + return; + pgto_base += len; pgfrom_base += len; @@ -406,6 +412,9 @@ _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len) char *vto; size_t copy; + if (!len) + return; + pgto = pages + (pgbase >> PAGE_SHIFT); pgbase &= ~PAGE_MASK; @@ -450,6 +459,9 @@ _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len) char *vfrom; size_t copy; + if (!len) + return; + pgfrom = pages + (pgbase >> PAGE_SHIFT); pgbase &= ~PAGE_MASK;