From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 F2D383C9ED0; Mon, 21 Sep 2026 12:11:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789992686; cv=none; b=XHVJkwSDDGG23uFdNnptOjjXb9ntbo6lZJ7u00zZ+PNILqDmN8eYAoBlkJwHTz2SYo2lX+hYUOI7Dq9rtwuqy5U/7/M/TDvkmHxb6IhpOGOx0Vr9GXu76ZbapmxrxtlKkzdL4RDs3GA5Krf0fITtYwTInE2S1Wq0jukSqOed3F8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789992686; c=relaxed/simple; bh=JnSnm1lDJ01Rj969zxsQOwm25oRkglMxjPcUzNiA6/s=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WeaVx44aw0alVoHhPuJBzEW9DPXfeb6d0UgBfumjGdPdskAXmKnSVKl4Xnq4tKOtJJAiJpjOVLaQjxbUqT0LyGQs34B1J49blsBzBUwBhyHKm5RF1r3bqCauIY7rH49gKTLibTbJoe/7ZaWh7HxU6lIP5c/URBAw3nF6FYWhq2M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OvoYvLux; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OvoYvLux" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 28D541F000FF; Mon, 21 Sep 2026 12:11:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789992684; bh=KyIzPYUauH3Qhtv7ngBSIIeQCucxdX5r54KBJoGH2DY=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=OvoYvLuxrkWMzUmtMrJWdgyuY3V5JYSkgXPFET2ZXCEVwMONVViYf6st9m7LX0DyW SVgOXdYPEbqMpIDFwZr3k0ygfpkjIzGj4d/zIUUHPJNNxjcqA+NZIjK8wH5Ip2mNqU WIfbMlFM9KodAVdmzGQ863kgolIMZYDdBqT9ZbJddwYhv24Tdh/DwASdLwMEhdnrJF FLjfNv/hn9TQZebeShCgOMdzWQY0BbjzZgZW/cAsYFbKElu5niHPDhhkZ0HhXP/lsr NZBuMuqdG/MaxI5RObzlGVOfjW6qyu1jVv2/pSu/a1Cn8BjUjZEr5sc6SKOZ27Rsvz Hv1ogzJE4fqkw== Date: Mon, 21 Sep 2026 13:11:20 +0100 From: Simon Horman To: Wentao Liang Cc: alexandre.torgue@foss.st.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, mcoquelin.stm32@gmail.com, netdev@vger.kernel.org, pabeni@redhat.com, treding@nvidia.com, stable@vger.kernel.org Subject: Re: [PATCH] net: stmmac: Fix MDIO node leak in stmmac_mdio_setup() Message-ID: <20260921121120.GK13925@horms.kernel.org> References: <20260917113945.2149361-1-vulab@iscas.ac.cn> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260917113945.2149361-1-vulab@iscas.ac.cn> On Thu, Sep 17, 2026 at 11:39:45AM +0000, Wentao Liang wrote: > stmmac_mdio_setup() acquires a reference on the MDIO node through > stmmac_of_get_mdio() and stores it in plat->mdio_node. If the allocation > of plat->mdio_bus_data fails, the function returns -ENOMEM and the > caller takes the error_put_phy path, which only releases plat->phy_node, > so the MDIO node reference is leaked. > > Release plat->mdio_node on this error path. > > Fixes: 1a981c0586c0 ("net: stmmac: Make MDIO bus reset optional") > Cc: stable@vger.kernel.org > Signed-off-by: Wentao Liang > --- > drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c > index 5cae2aa72906..09359ccb32ef 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c > @@ -356,8 +356,11 @@ static int stmmac_mdio_setup(struct plat_stmmacenet_data *plat, > plat->mdio_bus_data = devm_kzalloc(dev, > sizeof(*plat->mdio_bus_data), > GFP_KERNEL); > - if (!plat->mdio_bus_data) > + if (!plat->mdio_bus_data) { > + of_node_put(plat->mdio_node); > + plat->mdio_node = NULL; > return -ENOMEM; > + } > > plat->mdio_bus_data->needs_reset = true; > } Hi Wentao, As per my comment on another one of your recent patches, I think this change would be somewhat more robust against future changes to this function if it was implemented using a goto-driven unwind ladder, which is the generally preferred in Networking code. Something like this (compile tested only!): diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c index 3ea16d618215..ded352afd103 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c @@ -356,12 +356,17 @@ static int stmmac_mdio_setup(struct plat_stmmacenet_data *plat, sizeof(*plat->mdio_bus_data), GFP_KERNEL); if (!plat->mdio_bus_data) - return -ENOMEM; + goto err_put_mdio_node; plat->mdio_bus_data->needs_reset = true; } return 0; + +err_put_mdio_node: + of_node_put(plat->mdio_node); + plat->mdio_node = NULL; + return -ENOMEM; } /** -- pw-bot: changes-requested