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 6F00A330B2D; Thu, 28 May 2026 19:55:24 +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=1779998125; cv=none; b=Nd7+6Q/J2Vpq2BvDzx9/EbZfaZOB4za3C08paJ2KzrvIillsQrr1iAGxzaN+xUFxE2BGBJkb05Czum9q3FGAnVVH7P49Rm4asivnPg93dEtEhke+03457CakxoV4aqQ+YE8pDpVNqr3vdJTBAGeKIyamUgnLxUhoQclk0sbi+00= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779998125; c=relaxed/simple; bh=GncCrtrNwSKdjVOie3CjkljKns9b2Sk4RQwIfyh9XQw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PxRdtCXZqgyElETQytPeHtJAU8cFn2khB1+eEB+2CKX+u87qMVhxBy6nVk16xw6/Aup531Obc9DzXseBoOsTM5j/5p4pPsxa4vijMW07U86/2m17iOsibNgdQrC7oJemRFdOB9kWnRFPPxm1hnVF7LwfLYMlcYPsTAObepq+MZY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=GAGcaED+; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="GAGcaED+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CB36B1F000E9; Thu, 28 May 2026 19:55:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779998124; bh=RVlEKMjFx/nxwU5Y+zTUKPewxVwhej3qPBfKPVUkEL4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=GAGcaED+LTYdXf5VixWpksMDQaa9GPiC1qQLizmzRbpNyPNENarrop5zKQFhnjiXu 244aj8RVNTqsliLZTQLpHjksLdX2B7dC29x2V7KYvEtFkcNu9EXrytJjBkn/VlxvHF fzGMQg30Iph+75JsnV9qLbXd2pTQMDkgh4dlUNfg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, David Carlier , Maxime Chevallier , Jakub Kicinski , Sasha Levin Subject: [PATCH 7.0 062/461] net: ethtool: phy: avoid NULL deref when PHY driver is unbound Date: Thu, 28 May 2026 21:43:11 +0200 Message-ID: <20260528194648.710542907@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260528194646.819809818@linuxfoundation.org> References: <20260528194646.819809818@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 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ 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 Signed-off-by: Greg Kroah-Hartman --- net/ethtool/phy.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/net/ethtool/phy.c +++ b/net/ethtool/phy.c @@ -94,10 +94,12 @@ static int phy_prepare_data(const struct 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;