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 3B16CC433EF for ; Tue, 19 Jul 2022 12:56:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242211AbiGSM4E (ORCPT ); Tue, 19 Jul 2022 08:56:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242562AbiGSMyq (ORCPT ); Tue, 19 Jul 2022 08:54:46 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0280C98207; Tue, 19 Jul 2022 05:21:53 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 486D36183D; Tue, 19 Jul 2022 12:21:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 25E59C341C6; Tue, 19 Jul 2022 12:21:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658233312; bh=DUAa5U+dAGJ6yr8/kLhhqS6OZwSXQWeIRwQAoug3uHo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QpGoPaP8LwTibxSfVmElyEptH2PxhQNvsXb3+ahXY7iU8ZKHlpMQlLAFzYw71722j aWBO2EOhRghzGOwFfKtU6/i2ysrPY26WRkfYRjiF7DZ+iATOqq/PlHXpA+lehSKzWa fLUCYvPwHQ6eMTaZ0ewU2zwcs9xBvMtEUk7AXTVY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kuniyuki Iwashima , "David S. Miller" , Sasha Levin Subject: [PATCH 5.18 079/231] icmp: Fix data-races around sysctl. Date: Tue, 19 Jul 2022 13:52:44 +0200 Message-Id: <20220719114721.514621079@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220719114714.247441733@linuxfoundation.org> References: <20220719114714.247441733@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: Kuniyuki Iwashima [ Upstream commit 48d7ee321ea5182c6a70782aa186422a70e67e22 ] While reading icmp sysctl variables, they can be changed concurrently. So, we need to add READ_ONCE() to avoid data-races. Fixes: 4cdf507d5452 ("icmp: add a global rate limitation") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv4/icmp.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 72a375c7f417..97350a38a75d 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -253,11 +253,12 @@ bool icmp_global_allow(void) spin_lock(&icmp_global.lock); delta = min_t(u32, now - icmp_global.stamp, HZ); if (delta >= HZ / 50) { - incr = sysctl_icmp_msgs_per_sec * delta / HZ ; + incr = READ_ONCE(sysctl_icmp_msgs_per_sec) * delta / HZ; if (incr) WRITE_ONCE(icmp_global.stamp, now); } - credit = min_t(u32, icmp_global.credit + incr, sysctl_icmp_msgs_burst); + credit = min_t(u32, icmp_global.credit + incr, + READ_ONCE(sysctl_icmp_msgs_burst)); if (credit) { /* We want to use a credit of one in average, but need to randomize * it for security reasons. -- 2.35.1