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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99062C4332F for ; Tue, 7 Nov 2023 12:33:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234896AbjKGMdB (ORCPT ); Tue, 7 Nov 2023 07:33:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234940AbjKGMci (ORCPT ); Tue, 7 Nov 2023 07:32:38 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1937269F; Tue, 7 Nov 2023 04:13:06 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 02B00C433D9; Tue, 7 Nov 2023 12:13:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699359185; bh=0u7gFl7gn4Gkew7E30d2xthfQRLzASK3vTs/yybexQU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=f5cxo5z/voxdPg4VO+q69jNqv5/LksKECgYipKxT99r/PgMJSl/p5WQLCSuIas53r cxrsgd3zkAjH1T8cqezXHYufXERuh+XAfK3Y9TonBgy/gxh7iPYfsO+A1J26dVgh5F n3SaVGD0p6sE1MduETloNGKuzXZ5Lv0i/WEbvza6B8EXkp1RHysi4Q0A5ATIenS17a 9jCGxDuyqkooQ3smcgrW32ciYCufIVlMWc8XGynTLcH7edNpmvhZv4ljAnpbvBUPFS Idpd1uT4RyfV2J4JgXfVLcJvxGLNMvZF6IhtwakyuE1ZXsv97tFgCGa5oNzKfT3MFs tzPwXUe83kRew== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , "David S . Miller" , Sasha Levin , kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 5/9] net: annotate data-races around sk->sk_tx_queue_mapping Date: Tue, 7 Nov 2023 07:12:48 -0500 Message-ID: <20231107121256.3758858-5-sashal@kernel.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231107121256.3758858-1-sashal@kernel.org> References: <20231107121256.3758858-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.259 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet [ Upstream commit 0bb4d124d34044179b42a769a0c76f389ae973b6 ] This field can be read or written without socket lock being held. Add annotations to avoid load-store tearing. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- include/net/sock.h | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index f73ef7087a187..b021c8912e2cf 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1782,21 +1782,33 @@ static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) /* sk_tx_queue_mapping accept only upto a 16-bit value */ if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) return; - sk->sk_tx_queue_mapping = tx_queue; + /* Paired with READ_ONCE() in sk_tx_queue_get() and + * other WRITE_ONCE() because socket lock might be not held. + */ + WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue); } #define NO_QUEUE_MAPPING USHRT_MAX static inline void sk_tx_queue_clear(struct sock *sk) { - sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; + /* Paired with READ_ONCE() in sk_tx_queue_get() and + * other WRITE_ONCE() because socket lock might be not held. + */ + WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING); } static inline int sk_tx_queue_get(const struct sock *sk) { - if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) - return sk->sk_tx_queue_mapping; + if (sk) { + /* Paired with WRITE_ONCE() in sk_tx_queue_clear() + * and sk_tx_queue_set(). + */ + int val = READ_ONCE(sk->sk_tx_queue_mapping); + if (val != NO_QUEUE_MAPPING) + return val; + } return -1; } -- 2.42.0