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 5431C1C68C; Sun, 1 Sep 2024 16:44:18 +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=1725209058; cv=none; b=L+pbVGrLC2RjgPC74M/21DNI4rBdtokBVMQ11CH6Mpkz0wQKCfXYjkItiYDr3LK7qNF7i4NYr2Rhxkf8/7M8MGw1m4nlNSPlCNoK9Uq4JG/7ixJAijEb1Fq10BUTCUPXsGZNix8PQXY+O22ayKqAXhSyFCqah0J+xDKuIYRW9Tc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725209058; c=relaxed/simple; bh=q0HBfc2Z1bSH9A5fXrvNwGzeWPeLGyrY4WukfStV6fs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aYVZULA9MZjM0D/G+epT05yXRe1zkAch3poD9Ff4S7ejCdmsemMqQoSuR7pQvBlXMUnUga2iOHh8pYD785uRp+7fbVvDba/uew4VeXKa8gQnXmhXG636B/Z9PMtyXytr1UPb8HFwCZ0hPL/jyMxRB4sIWGREPRdSU0zH8PQWVEc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=J+27Pz3D; 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="J+27Pz3D" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B8A9CC4CEC3; Sun, 1 Sep 2024 16:44:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1725209058; bh=q0HBfc2Z1bSH9A5fXrvNwGzeWPeLGyrY4WukfStV6fs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=J+27Pz3DXutAWwJcP7VuHb+bplP0pAySQUCA4jNyANHbyvDmhQP7s27xydbcjmEYS NyMadROu8XDJLqPM6+C/Y2skbUw/m4EEB7iKQkeLcXPRN2GHEUxQzHwpnQvhL4taaf Oq8pvbNd6orE6L4hDP2qfhQ8W+SNrAsc7lemCxAs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jamie Bainbridge , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.4 119/134] ethtool: check device is present when getting link settings Date: Sun, 1 Sep 2024 18:17:45 +0200 Message-ID: <20240901160814.558081285@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240901160809.752718937@linuxfoundation.org> References: <20240901160809.752718937@linuxfoundation.org> User-Agent: quilt/0.67 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 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jamie Bainbridge [ Upstream commit a699781c79ecf6cfe67fb00a0331b4088c7c8466 ] A sysfs reader can race with a device reset or removal, attempting to read device state when the device is not actually present. eg: [exception RIP: qed_get_current_link+17] #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede] #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb crash> struct net_device.state ffff9a9d21336000 state = 5, state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100). The device is not present, note lack of __LINK_STATE_PRESENT (0b10). This is the same sort of panic as observed in commit 4224cfd7fb65 ("net-sysfs: add check for netdevice being present to speed_show"). There are many other callers of __ethtool_get_link_ksettings() which don't have a device presence check. Move this check into ethtool to protect all callers. Fixes: d519e17e2d01 ("net: export device speed and duplex via sysfs") Fixes: 4224cfd7fb65 ("net-sysfs: add check for netdevice being present to speed_show") Signed-off-by: Jamie Bainbridge Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/core/ethtool.c | 3 +++ net/core/net-sysfs.c | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/net/core/ethtool.c b/net/core/ethtool.c index 9ae38c3e2bf0a..f0346cf4462e0 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -549,6 +549,9 @@ int __ethtool_get_link_ksettings(struct net_device *dev, if (!dev->ethtool_ops->get_link_ksettings) return -EOPNOTSUPP; + if (!netif_device_present(dev)) + return -ENODEV; + memset(link_ksettings, 0, sizeof(*link_ksettings)); return dev->ethtool_ops->get_link_ksettings(dev, link_ksettings); } diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index ad45f13a0370b..bcad7028bbf45 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -212,7 +212,7 @@ static ssize_t speed_show(struct device *dev, if (!rtnl_trylock()) return restart_syscall(); - if (netif_running(netdev) && netif_device_present(netdev)) { + if (netif_running(netdev)) { struct ethtool_link_ksettings cmd; if (!__ethtool_get_link_ksettings(netdev, &cmd)) -- 2.43.0