From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-4098462-1520452839-2-10469784463858391167 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1520452839; b=pHZKn9GqIq7P8cnPXHwz65WqKiYWKYVzElkNXot9i9r5RE8 lFpe+Cdj/efi6tBJ1KXp05Q1weyeZ9isYeka7u+wnxPrlWERO/szmx3CoSx86jdF yM5B7YvvQdF9f7ecpv7uLwWELFWop3WKLj2etpuop1xXkMViDtmq/XB4Dw6MwDeu wys9VaoNynwhc13mLRaMMu7Z3omTa7zeZqqr4IkOlYphkl59vFIqDj/kzSU8jJln tjlpSTbGSxkipLJYGoCvFn+ZknxtomW2b5yCesepTAioVgjBMTHyhjhuqisBeDbF uBuViFJOC4Y2MboD2yZj1dHybU7fm4BGapUDm4Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1520452839; bh=VJcszIFopjX1IjQW49o2atiEt7 LLHV4FINcodO5REO0=; b=iLRYfFGhtth3l+m0JXtHaeD9OGLq7HDq3VSZIdVmhv +6uAtWaryK9MXZok9EwcO/wx9Nut9yBQuAUjH/klHRtPa8m7iy0xqICmpnwACDb/ ZevAcI+PpDHqeQ5EyYJZ3KVXzgs1FX7+3brG4xqk5lPn2bhDkNzTaH6G74G43t/U zbL1LQEYlP4TD2+YM1i0ukXMgQP6P37vJJKefCOg2AtUgZJ3gMZguV6y9kfkYAYd pQFjzc1RbLmVd1jDRYoaAFuyzJMCpUSNDxAPLB7BYs6qAw1RUHAuJqfUoLbCinxg DWiSYMdMNT0nyJ6CGhR8HGQXcXGGMVaUKYnv+2BE1cCw== ARC-Authentication-Results: i=1; mx4.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx4.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965668AbeCGTrG (ORCPT ); Wed, 7 Mar 2018 14:47:06 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:44868 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754916AbeCGTrE (ORCPT ); Wed, 7 Mar 2018 14:47:04 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julian Wiedmann , "David S. Miller" Subject: [PATCH 4.14 077/110] s390/qeth: fix overestimated count of buffer elements Date: Wed, 7 Mar 2018 11:39:00 -0800 Message-Id: <20180307191049.591681083@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180307191039.748351103@linuxfoundation.org> References: <20180307191039.748351103@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Julian Wiedmann [ Upstream commit 12472af89632beb1ed8dea29d4efe208ca05b06a ] qeth_get_elements_for_range() doesn't know how to handle a 0-length range (ie. start == end), and returns 1 when it should return 0. Such ranges occur on TSO skbs, where the L2/L3/L4 headers (and thus all of the skb's linear data) are skipped when mapping the skb into regular buffer elements. This overestimation may cause several performance-related issues: 1. sub-optimal IO buffer selection, where the next buffer gets selected even though the skb would actually still fit into the current buffer. 2. forced linearization, if the element count for a non-linear skb exceeds QETH_MAX_BUFFER_ELEMENTS. Rather than modifying qeth_get_elements_for_range() and adding overhead to every caller, fix up those callers that are in risk of passing a 0-length range. Fixes: 2863c61334aa ("qeth: refactor calculation of SBALE count") Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/s390/net/qeth_core_main.c | 10 ++++++---- drivers/s390/net/qeth_l3_main.c | 11 ++++++----- 2 files changed, 12 insertions(+), 9 deletions(-) --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -3861,10 +3861,12 @@ EXPORT_SYMBOL_GPL(qeth_get_elements_for_ int qeth_get_elements_no(struct qeth_card *card, struct sk_buff *skb, int extra_elems, int data_offset) { - int elements = qeth_get_elements_for_range( - (addr_t)skb->data + data_offset, - (addr_t)skb->data + skb_headlen(skb)) + - qeth_get_elements_for_frags(skb); + addr_t end = (addr_t)skb->data + skb_headlen(skb); + int elements = qeth_get_elements_for_frags(skb); + addr_t start = (addr_t)skb->data + data_offset; + + if (start != end) + elements += qeth_get_elements_for_range(start, end); if ((elements + extra_elems) > QETH_MAX_BUFFER_ELEMENTS(card)) { QETH_DBF_MESSAGE(2, "Invalid size of IP packet " --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -2633,11 +2633,12 @@ static void qeth_tso_fill_header(struct static int qeth_l3_get_elements_no_tso(struct qeth_card *card, struct sk_buff *skb, int extra_elems) { - addr_t tcpdptr = (addr_t)tcp_hdr(skb) + tcp_hdrlen(skb); - int elements = qeth_get_elements_for_range( - tcpdptr, - (addr_t)skb->data + skb_headlen(skb)) + - qeth_get_elements_for_frags(skb); + addr_t start = (addr_t)tcp_hdr(skb) + tcp_hdrlen(skb); + addr_t end = (addr_t)skb->data + skb_headlen(skb); + int elements = qeth_get_elements_for_frags(skb); + + if (start != end) + elements += qeth_get_elements_for_range(start, end); if ((elements + extra_elems) > QETH_MAX_BUFFER_ELEMENTS(card)) { QETH_DBF_MESSAGE(2,