From patchwork Wed Mar 9 00:28:43 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 594582 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 999A314031D; Wed, 9 Mar 2016 11:30:52 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1adS1a-0006et-Ff; Wed, 09 Mar 2016 00:30:50 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1adRzm-0005T2-0u for kernel-team@lists.ubuntu.com; Wed, 09 Mar 2016 00:28:58 +0000 Received: from 1.general.kamal.us.vpn ([10.172.68.52] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1adRzk-00035k-WA; Wed, 09 Mar 2016 00:28:57 +0000 Received: from kamal by fourier with local (Exim 4.86) (envelope-from ) id 1adRzY-0007Yb-Ok; Tue, 08 Mar 2016 16:28:44 -0800 From: Kamal Mostafa To: Ken-ichirou MATSUZAWA Subject: [3.19.y-ckt stable] Patch "netlink: not trim skb for mmaped socket when dump" has been added to the 3.19.y-ckt tree Date: Tue, 8 Mar 2016 16:28:43 -0800 Message-Id: <1457483323-29014-1-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.0 X-Extended-Stable: 3.19 Cc: Kamal Mostafa , Ken-ichirou MATSUZAWA , "David S . Miller" , kernel-team@lists.ubuntu.com X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com This is a note to let you know that I have just added a patch titled netlink: not trim skb for mmaped socket when dump to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.8-ckt16. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ---8<------------------------------------------------------------ From b002bb3f19597979b836312d8bbc3a5f7882ca68 Mon Sep 17 00:00:00 2001 From: Ken-ichirou MATSUZAWA Date: Fri, 29 Jan 2016 10:45:50 +0900 Subject: netlink: not trim skb for mmaped socket when dump commit aa3a022094fac7f6e48050e139fa8a5a2e3265ce upstream. We should not trim skb for mmaped socket since its buf size is fixed and userspace will read as frame which data equals head. mmaped socket will not call recvmsg, means max_recvmsg_len is 0, skb_reserve was not called before commit: db65a3aaf29e. Fixes: db65a3aaf29e (netlink: Trim skb to alloc size to avoid MSG_TRUNC) Signed-off-by: Ken-ichirou MATSUZAWA Signed-off-by: David S. Miller Signed-off-by: Kamal Mostafa --- net/netlink/af_netlink.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) -- 2.7.0 diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index d78848d..71c03e3 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -2703,7 +2703,8 @@ static int netlink_dump(struct sock *sk) * reasonable static buffer based on the expected largest dump of a * single netdev. The outcome is MSG_TRUNC error. */ - skb_reserve(skb, skb_tailroom(skb) - alloc_size); + if (!netlink_rx_is_mmaped(sk)) + skb_reserve(skb, skb_tailroom(skb) - alloc_size); netlink_skb_set_owner_r(skb, sk); len = cb->dump(skb, cb);