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 7A26625B0B1 for ; Fri, 22 May 2026 12:51:03 +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=1779454264; cv=none; b=sYODG3eXzVf54a+m1mzsD5x0rck/xtA+lElPiVtMlVo6b0B9LTU9uOkYpxckSSSIpGmGbc0yLILHMzd0uyUhAIqolrO41jfAcwAhnM9dBN5njRbCXNb7UObVj1piuPc2pIM321EDh0qg85fudU1OnKLe5ASGmfvt148pVba2IXs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779454264; c=relaxed/simple; bh=d8fNWU/LLkxUNGy4nQZyqFOht7UE1o1eO1HCkTcsQ34=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=e8Ce0DP9Bcs+qaCAysS+X3BBMREpMc2rAAwDrZTYTnM5upssOUbvj2WfDfpghfP09dWqu86N7HGv3viJgOriNBpCp+QjOmTikZT9wFOfth8s2c97dxHU98KKUPKHVB4pPylqV8RoUf0jzX38TKGASNgeFW1evRixXguJGU5Fh+Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LYHdc12I; 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="LYHdc12I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B34301F00A3F; Fri, 22 May 2026 12:51:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779454263; bh=KmGrhJh7D+SVkuQw1UciJG9VTMyjSC4gRhlARXlqOWA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=LYHdc12ITZP6zmbQtHSW/eXYjQJ8rIW5u9aEKlAw4CbVBwE8uBWp7tCPk5MzEqhg4 /LqGEHmWOe74oG5MHRm6kABByUTzOTh698h1xg2qdjTa7CBcriBrcbbc+C+QRPsIlv lM3PzOqmb2HqQWb2SZxr0KTlsuE9auLkymr5mQAdoh2dxkiJuT3Few9mCjmE9LUfZK wHWIqKwy2Nos5UMHg7XA7DitepOK/3DLjmYixPf1tlz2tSLBUamYbzR1B85BiniRCt /d9hKpREaQFkn1uE6wkybx0rl78HldlXKxalH8RP94M2fKFAYqqW05p1HbHV0ajNnk ur8209H4A2+3A== From: Sasha Levin To: stable@vger.kernel.org Cc: David Carlier , Maxime Chevallier , Jakub Kicinski , Sasha Levin Subject: [PATCH 7.0.y 2/2] net: ethtool: phy: avoid NULL deref when PHY driver is unbound Date: Fri, 22 May 2026 08:51:00 -0400 Message-ID: <20260522125100.3837432-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260522125100.3837432-1-sashal@kernel.org> References: <2026051922-likely-backless-a84b@gregkh> <20260522125100.3837432-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: David Carlier [ Upstream commit e3adf69f8eb121a9128c2b0029efd050d3649153 ] phydev->drv can become NULL while the phy_device is still attached to its net_device, namely after the PHY driver is unbound via sysfs: echo > /sys/bus/mdio_bus/drivers//unbind phy_remove() clears phydev->drv but doesn't call phy_detach(), so the phy_device stays in the link topology xarray and ethnl_req_get_phydev() still hands it back. ETHTOOL_MSG_PHY_GET then oopses on: rep_data->drvname = kstrdup(phydev->drv->name, GFP_KERNEL); drvname is already treated as optional by phy_reply_size(), phy_fill_reply() and phy_cleanup_data(), so just skip the allocation when there is no driver bound. Fixes: 9dd2ad5e92b9 ("net: ethtool: phy: Convert the PHY_GET command to generic phy dump") Cc: stable@vger.kernel.org # 6.13.x Signed-off-by: David Carlier Reviewed-by: Maxime Chevallier Tested-by: Maxime Chevallier Link: https://patch.msgid.link/20260509215046.107157-1-devnexen@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ethtool/phy.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/net/ethtool/phy.c b/net/ethtool/phy.c index cb1e0aea450f9..98392a3c34b5b 100644 --- a/net/ethtool/phy.c +++ b/net/ethtool/phy.c @@ -94,10 +94,12 @@ static int phy_prepare_data(const struct ethnl_req_info *req_info, if (!rep_data->name) return -ENOMEM; - rep_data->drvname = kstrdup(phydev->drv->name, GFP_KERNEL); - if (!rep_data->drvname) { - ret = -ENOMEM; - goto err_free_name; + if (phydev->drv) { + rep_data->drvname = kstrdup(phydev->drv->name, GFP_KERNEL); + if (!rep_data->drvname) { + ret = -ENOMEM; + goto err_free_name; + } } rep_data->upstream_type = pdn->upstream_type; -- 2.53.0