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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 47758C33CAF for ; Thu, 16 Jan 2020 18:42:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 06CB12077B for ; Thu, 16 Jan 2020 18:42:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579200161; bh=7pl7lK1KOW0b4GqLq3o0CUIRMgonuai131WNRNpX6/U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SDpIuRkyizhdHnBiye0Dr5+fTVv/M6Z1D8egEcXpjH2D7aMRZA9qJHVJx24rl7eGP dX5QzvbxwUVdKv+TCvMqFTW4ok007CFBpAI94hBPkHRPIpYCInxqCvE4URob6rMKvR Xfc0hisZd1pCZdUNAssgOy7zusRLD7Y+YhiC0oEA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390343AbgAPSmk (ORCPT ); Thu, 16 Jan 2020 13:42:40 -0500 Received: from mail.kernel.org ([198.145.29.99]:52014 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389471AbgAPRLZ (ORCPT ); Thu, 16 Jan 2020 12:11:25 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 959DD21D56; Thu, 16 Jan 2020 17:11:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194685; bh=7pl7lK1KOW0b4GqLq3o0CUIRMgonuai131WNRNpX6/U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2JctedowzlH7nwWDLpBfsG/QRNICScbDHiUM1hga5P3d+hAM42hbomrEQPYVnHKj+ LebhAxNZ11paoKWtVmdJG0ANnPzGiiheAFpbXsssnv3LQGWmhPStUoJpGsGMAHPkcT iRJLtgfhf80Bo7VkSEaJjdZCD59PzEQo7vlZ3R/g= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Jonathan Lemon , Daniel Borkmann , Sasha Levin , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 529/671] xsk: avoid store-tearing when assigning queues Date: Thu, 16 Jan 2020 12:02:47 -0500 Message-Id: <20200116170509.12787-266-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116170509.12787-1-sashal@kernel.org> References: <20200116170509.12787-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: Björn Töpel [ Upstream commit 94a997637c5b562fa0ca44fca1d2cd02ec08236f ] Use WRITE_ONCE when doing the store of tx, rx, fq, and cq, to avoid potential store-tearing. These members are read outside of the control mutex in the mmap implementation. Acked-by: Jonathan Lemon Fixes: 37b076933a8e ("xsk: add missing write- and data-dependency barrier") Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin --- net/xdp/xsk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index c90854bc3048..b580078f04d1 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -320,7 +320,7 @@ static int xsk_init_queue(u32 entries, struct xsk_queue **queue, /* Make sure queue is ready before it can be seen by others */ smp_wmb(); - *queue = q; + WRITE_ONCE(*queue, q); return 0; } -- 2.20.1