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 20F1F359A72 for ; Sat, 28 Feb 2026 18:13:08 +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=1772302388; cv=none; b=rjbdmIg5RvTLMb2nmjb4INAU+jCuGKMqWtYy8REE7gR+k8cObdS9juZStFAJjG0Eb8PQoiaxYoEqft33CM+DwVEjkCkLOWqwJVoi2vMP2yzOfAEZA42ZWDOt6qZ+F+b2hODnriGW4+LEC3DHKSqOlH2RLvw8/ldG1u1CAhd1oig= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302388; c=relaxed/simple; bh=gChsSVYdvw2gELx2LPXAxLNd/alJq9G8YTsjwNelCDg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ngsCdv8LWELlU1nVxIKwRZywLaUBnoprviCCJ1Fa96WatOioM3zhHD3sWmNRwbgbMcCD3gml+87P3W5OcGaOykSAGCrG3TUpO3LuaCwhSenjKDG1yHqOjUsO7lbopt7rKCbFhOrqzD0WFjThKlUTuDRSMqrvJ3IsAGk/Ddj+6B8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=n0YMMCYK; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="n0YMMCYK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 845EDC116D0; Sat, 28 Feb 2026 18:13:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302388; bh=gChsSVYdvw2gELx2LPXAxLNd/alJq9G8YTsjwNelCDg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n0YMMCYKnfgs2PD9Vhr3m8NQzbQSv7ceEKgirHTr5Oon9IM9M0/+AFtmRhBFJvF+W 5Zm7ME/nTs0RQwLNqqtP9XJMQmMKVET/YnvZNlWLh6UzRPt+NBF+uAqun6A6W3gh+z 2ChBtm9QNOM42U0ELTmSU5fB/1Ou/oihgg5QDEVYht1ssUk3rfCroxvPenp3Zufz64 yKFk2Dw03Z0Ph6Q52rSYTB6wi5KL/crtO+zvVoQHTH7ghIbeGC9pEDDP0f1MM9qUpp ls7Bptrze3e29zTySbiqS5idE+sSCRSi4qHx8Eq5b29M1svRMRc4lBlR6zKoipIzXT wSHhI8tIKKLjA== From: Sasha Levin To: patches@lists.linux.dev Cc: Anders Grahn , Florian Westphal , Sasha Levin Subject: [PATCH 6.1 117/232] netfilter: nft_counter: fix reset of counters on 32bit archs Date: Sat, 28 Feb 2026 13:09:30 -0500 Message-ID: <20260228181127.1592657-117-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181127.1592657-1-sashal@kernel.org> References: <20260228181127.1592657-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit 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 79c3bbaa7e13e..0a3f9416f8464 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 8d19bd0012770..7411bba75d4cb 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