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 814A238F623 for ; Sat, 28 Feb 2026 18:09:11 +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=1772302151; cv=none; b=aqtBvbUWKkGrid8vwWu1xZSvwmJXb5iTcKbpbiCju9PFCiDBHn0Z0Vzq5P3psKhtXQ+9c4dKjfUwfF6qp7kD7lOpzPwzS/IDT/YOW5W6IOWYdgTjAmUcpQKWHYZBhwbJ/dSVo/CcRDs5LFnMSycjUtw+T39sHNk73LKEXCFzJdA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302151; c=relaxed/simple; bh=IoVJKt8d0ZBIvaFm4KRkA66m+tHk/dXXJ3YWsJp109k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=R5vuUAlJvur7qz3tKHIEtzhWE8/f6LQIMPWCx5cj0e0hDhT4iubU2XxbRilpOMSI4E5q4Er1iFPjTWbCDvJ71uO0XLmpzFZX+tMuCdd9ahvt1bqbENWHu11IYpSRbMrE0qYvAEaqch7BAGy58L9gFNE/Cqcs/eNEkFq3mIZUlVU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rqY9YPCX; 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="rqY9YPCX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2689C116D0; Sat, 28 Feb 2026 18:09:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302151; bh=IoVJKt8d0ZBIvaFm4KRkA66m+tHk/dXXJ3YWsJp109k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rqY9YPCXTfzBqm8FLDTSWPj0cLvczhmCoABjPNh6YIJi4tFBgGafOqbhxH7SELxCd gPkeKuYOONGyo7awLQrivJLgIoYPTRojqqQ7TOxav2WRFtb+IyFWfS3gPTxQIARe9M cP7VEagowP5wNjFre+YetZqKZOfA1yZwTWfR4jzR1OKFN8HcfbwVhy+Km0dHt1zCTQ QIHT8ZHNZ4SJa9XDyQ0NDr2dQU5yztVYCf+wW976DPbykxPA7aCM4FR1fcKS2TbNLr 6S+Arvh432VNfoxS35wYY5JubvsohLXPEXpjQ0Tpt/aoZlOSJHDZ8nTMysmkR6Vq1a WwysB+U/mOwjw== From: Sasha Levin To: patches@lists.linux.dev Cc: Anders Grahn , Florian Westphal , Sasha Levin Subject: [PATCH 6.6 146/283] netfilter: nft_counter: fix reset of counters on 32bit archs Date: Sat, 28 Feb 2026 13:04:48 -0500 Message-ID: <20260228180709.1583486-146-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228180709.1583486-1-sashal@kernel.org> References: <20260228180709.1583486-1-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 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