From mboxrd@z Thu Jan 1 00:00:00 1970 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=-19.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 748A4C433E6 for ; Mon, 8 Feb 2021 17:14:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3756964DF0 for ; Mon, 8 Feb 2021 17:14:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233597AbhBHROG (ORCPT ); Mon, 8 Feb 2021 12:14:06 -0500 Received: from mail.kernel.org ([198.145.29.99]:35332 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233460AbhBHPZ1 (ORCPT ); Mon, 8 Feb 2021 10:25:27 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id ABEC364F1B; Mon, 8 Feb 2021 15:15:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1612797315; bh=ZIaY/+E9j/6JBq23Zsdk3Qjd+AUNB8uNIfk4Df16bYg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KBeqsbk/NqjrziMauW62eXVhfozTqofaytMK7MQswuH+YudlNGGnAGg/WOcf0lBNg o/1zdI5oS0GDMRcwexwnfg9OKMDqMKx0mJfUK6OKn/r68X6ToC4qBf8LY5JPPVaRDS J6wMQeP7oRE/sGvFA0x6TzxIsyLwS2d714ZtDZ6g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "A. Duvnjak" , Chuck Lever , Sasha Levin Subject: [PATCH 5.10 035/120] SUNRPC: Fix NFS READs that start at non-page-aligned offsets Date: Mon, 8 Feb 2021 16:00:22 +0100 Message-Id: <20210208145819.792600794@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210208145818.395353822@linuxfoundation.org> References: <20210208145818.395353822@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chuck Lever [ Upstream commit bad4c6eb5eaa8300e065bd4426727db5141d687d ] Anj Duvnjak reports that the Kodi.tv NFS client is not able to read video files from a v5.10.11 Linux NFS server. The new sendpage-based TCP sendto logic was not attentive to non- zero page_base values. nfsd_splice_read() sets that field when a READ payload starts in the middle of a page. The Linux NFS client rarely emits an NFS READ that is not page- aligned. All of my testing so far has been with Linux clients, so I missed this one. Reported-by: A. Duvnjak BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=211471 Fixes: 4a85a6a3320b ("SUNRPC: Handle TCP socket sends with kernel_sendpage() again") Signed-off-by: Chuck Lever Tested-by: A. Duvnjak Signed-off-by: Sasha Levin --- net/sunrpc/svcsock.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 4404c491eb388..fa7b7ae2c2c5f 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1113,14 +1113,15 @@ static int svc_tcp_sendmsg(struct socket *sock, struct msghdr *msg, unsigned int offset, len, remaining; struct bio_vec *bvec; - bvec = xdr->bvec; - offset = xdr->page_base; + bvec = xdr->bvec + (xdr->page_base >> PAGE_SHIFT); + offset = offset_in_page(xdr->page_base); remaining = xdr->page_len; flags = MSG_MORE | MSG_SENDPAGE_NOTLAST; while (remaining > 0) { if (remaining <= PAGE_SIZE && tail->iov_len == 0) flags = 0; - len = min(remaining, bvec->bv_len); + + len = min(remaining, bvec->bv_len - offset); ret = kernel_sendpage(sock, bvec->bv_page, bvec->bv_offset + offset, len, flags); -- 2.27.0