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 A4EAE30FC1B; Wed, 28 Jan 2026 15:52:17 +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=1769615537; cv=none; b=PLrGiuIgNEzEVW6q1dAVrdgcoPsvpgx2etZl3QSZ//Eq6aVxA+g2jzBaYm1PsUTK5csn0F0+AwsMSDk26bBoD/bn1ACUYfoO0klOHfsecm2Tjc17KuGaR7Eprm5nim4lPgKtAZXL3eZMw3ZVgpnPPFI6ZBA4B4EGLuaGosbc7Pc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769615537; c=relaxed/simple; bh=zDbrUndZMsgRO/BtVY74YLPnaEWATsIKBzSHT7JL+c4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ryhPaRgipRq1wXDP8lE4Ud/GOH7vqwbAFQjEqdLUyfzkmS2SFjwE2y3AUbwNP9tJqnBrVChvus++Np1xB2NBKx3NeyE7HMz/7puCUejTSRTvCV0/gO6Up8ySxQURiRz0t21QbEHrD8Z0/Do+rJLn0UsYxn9CGikSheFeYPty07I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=D13hb9Zp; 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="D13hb9Zp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D63D7C4CEF1; Wed, 28 Jan 2026 15:52:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1769615537; bh=zDbrUndZMsgRO/BtVY74YLPnaEWATsIKBzSHT7JL+c4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D13hb9ZpVbJfq7inQogOi/h/UXEJIinFOyYL8I9cW+Gi/rW/dsYCo/y2LotfX7LXd tFJygH32LYLuhziBUDbXpD7Vj0lFcMH0rnOMs/EGBZuOe/xevJy4MdMF5j+gt/79SL nLUd3w/l5TY2ehYWnfBpZ+/VjDtENJhzocltuEV4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, David Yang , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 039/227] veth: fix data race in veth_get_ethtool_stats Date: Wed, 28 Jan 2026 16:21:24 +0100 Message-ID: <20260128145345.749801702@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260128145344.331957407@linuxfoundation.org> References: <20260128145344.331957407@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: David Yang [ Upstream commit b47adaab8b3d443868096bac08fdbb3d403194ba ] In veth_get_ethtool_stats(), some statistics protected by u64_stats_sync, are read and accumulated in ignorance of possible u64_stats_fetch_retry() events. These statistics, peer_tq_xdp_xmit and peer_tq_xdp_xmit_err, are already accumulated by veth_xdp_xmit(). Fix this by reading them into a temporary buffer first. Fixes: 5fe6e56776ba ("veth: rely on peer veth_rq for ndo_xdp_xmit accounting") Signed-off-by: David Yang Link: https://patch.msgid.link/20260114122450.227982-1-mmyangfl@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/veth.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index cc502bf022d55..b00613cb07cf0 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -228,16 +228,20 @@ static void veth_get_ethtool_stats(struct net_device *dev, const struct veth_rq_stats *rq_stats = &rcv_priv->rq[i].stats; const void *base = (void *)&rq_stats->vs; unsigned int start, tx_idx = idx; + u64 buf[VETH_TQ_STATS_LEN]; size_t offset; - tx_idx += (i % dev->real_num_tx_queues) * VETH_TQ_STATS_LEN; do { start = u64_stats_fetch_begin(&rq_stats->syncp); for (j = 0; j < VETH_TQ_STATS_LEN; j++) { offset = veth_tq_stats_desc[j].offset; - data[tx_idx + j] += *(u64 *)(base + offset); + buf[j] = *(u64 *)(base + offset); } } while (u64_stats_fetch_retry(&rq_stats->syncp, start)); + + tx_idx += (i % dev->real_num_tx_queues) * VETH_TQ_STATS_LEN; + for (j = 0; j < VETH_TQ_STATS_LEN; j++) + data[tx_idx + j] += buf[j]; } pp_idx = idx + dev->real_num_tx_queues * VETH_TQ_STATS_LEN; -- 2.51.0