From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E5942C11CF; Wed, 25 Feb 2026 06:56:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772002572; cv=none; b=kKiSsDcgyBy5T58PN8cna/zTnWJnCSB6dZKXDeDwX8hVbGGdaTbYV5Y6/l5c0nNP13fhBhTSBxa7eI+B/p+nuURr05CfJ/IW4FIjfRP9Quql50pQTut6IYJIklkJa03dKBMxqe8U8IcurvgEKwlEVS6klWBerhC6XuUZeHozmoc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772002572; c=relaxed/simple; bh=J4H73/C9pZBj6gmXWNKk7nyH6qQlIC+mV4XRk+VZd6M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AfVQY8U1pXH2aSRswL0DyraDGDxJd8YELNjQu/ILwuCj11TlgxE2OtCqkCwvNXeaBhbEIQkNSA5LePOXNLNgpwQeisNYY5xVVeAsrOfMx1JBdkjynRbI1G0El2V3c4tm3V87Lz0Cls9fxAvFZ1c1XcHADbXNzJrDnLUo/u3ruPg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=DbtyuOZt; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="DbtyuOZt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7588BC116D0; Wed, 25 Feb 2026 06:56:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1772002572; bh=J4H73/C9pZBj6gmXWNKk7nyH6qQlIC+mV4XRk+VZd6M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DbtyuOZtsMwnk323ZycW/2B0ds8nSg636Z+2H74l9FAvOjdoMAtRU4zG7z6QWOFyQ RC2OYGQ52TU4XsVrmf3F7Oa5MGOS8o+7w2fqI1sN21YTTd/r4H6BNwQYuBbuwtzKVM o3PlUA5oLZF9ECMbjHfCnZo/iYba9YiNP0Zchv2s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Anders Grahn , Florian Westphal , Sasha Levin Subject: [PATCH 6.18 307/641] netfilter: nft_counter: fix reset of counters on 32bit archs Date: Tue, 24 Feb 2026 17:20:33 -0800 Message-ID: <20260225012356.173979090@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260225012348.915798704@linuxfoundation.org> References: <20260225012348.915798704@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Anders Grahn [ Upstream commit 1e13f27e0675552161ab1778be9a23a636dde8a7 ] nft_counter_reset() calls u64_stats_add() with a negative value to reset the counter. This will work on 64bit archs, hence the negative value added will wrap as a 64bit value which then can wrap the stat counter as well. On 32bit archs, the added negative value will wrap as a 32bit value and _not_ wrapping the stat counter properly. In most cases, this would just lead to a very large 32bit value being added to the stat counter. Fix by introducing u64_stats_sub(). Fixes: 4a1d3acd6ea8 ("netfilter: nft_counter: Use u64_stats_t for statistic.") Signed-off-by: Anders Grahn Signed-off-by: Florian Westphal Signed-off-by: Sasha Levin --- include/linux/u64_stats_sync.h | 10 ++++++++++ net/netfilter/nft_counter.c | 4 ++-- 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/include/linux/u64_stats_sync.h b/include/linux/u64_stats_sync.h index 457879938fc19..3366090a86bd2 100644 --- a/include/linux/u64_stats_sync.h +++ b/include/linux/u64_stats_sync.h @@ -89,6 +89,11 @@ static inline void u64_stats_add(u64_stats_t *p, unsigned long val) local64_add(val, &p->v); } +static inline void u64_stats_sub(u64_stats_t *p, s64 val) +{ + local64_sub(val, &p->v); +} + static inline void u64_stats_inc(u64_stats_t *p) { local64_inc(&p->v); @@ -130,6 +135,11 @@ static inline void u64_stats_add(u64_stats_t *p, unsigned long val) p->v += val; } +static inline void u64_stats_sub(u64_stats_t *p, s64 val) +{ + p->v -= val; +} + static inline void u64_stats_inc(u64_stats_t *p) { p->v++; diff --git a/net/netfilter/nft_counter.c b/net/netfilter/nft_counter.c index cc73253294963..0d70325280cc5 100644 --- a/net/netfilter/nft_counter.c +++ b/net/netfilter/nft_counter.c @@ -117,8 +117,8 @@ static void nft_counter_reset(struct nft_counter_percpu_priv *priv, nft_sync = this_cpu_ptr(&nft_counter_sync); u64_stats_update_begin(nft_sync); - u64_stats_add(&this_cpu->packets, -total->packets); - u64_stats_add(&this_cpu->bytes, -total->bytes); + u64_stats_sub(&this_cpu->packets, total->packets); + u64_stats_sub(&this_cpu->bytes, total->bytes); u64_stats_update_end(nft_sync); local_bh_enable(); -- 2.51.0