From patchwork Tue Feb 18 00:24:43 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qasim Ijaz X-Patchwork-Id: 13978795 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-wm1-f50.google.com (mail-wm1-f50.google.com [209.85.128.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8C976E545; Tue, 18 Feb 2025 00:25:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.50 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739838327; cv=none; b=HpXPe/MmxmVfYPdGKRDIvVVWG9TnivhnHJRioc9HSGpm6Uf45cHVG/YKKZpQkTVB34K1Pq/KmGNdGEjrJ0tI8JLNBiYxKpDKjXdrCX8klF/kK7OoL1nwFsPNSSlQDktkh7jnZNKxLyFIb+EPxkVCeEXQuax3RSO9iMWzEpe+IlU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739838327; c=relaxed/simple; bh=EFJw1G6AdYPAxqc3eJvXKne5aFMBnMqVqo01SdhVK8s=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=n2lN1PmEN2SgS6mBuM6Oo2h7wCjSpCRlp+CMQeXlyLmMeNa+lm1ch7VdXJ1gRaIBleKsbT2OwXSJ6x/jCoobyam+/lqTclc6/GjkFceZsS2Wy9pndItcGEps0xL7kPymQDycUHz2PD6HuTxQ8qWIlrXZIOGtFtHVJwZI/j0hmvo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Ny6faVZL; arc=none smtp.client-ip=209.85.128.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Ny6faVZL" Received: by mail-wm1-f50.google.com with SMTP id 5b1f17b1804b1-438a3216fc2so51026305e9.1; Mon, 17 Feb 2025 16:25:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1739838324; x=1740443124; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=8m1uQh6w5iYJ3orp8b5EeRdmeUvkTNV6vuD529TfFW8=; b=Ny6faVZLYssWlwOdj2XF1xCuezvAWM+r9xKXLicftU+sTUGu96MAa4rx0Mi4bHhhyO PzDrcyY7Jx988b/vdwCkozW5IUSi9es5iWgkaA+tEv4/x70nNIdTc9qPK4qQned9Tser hvREAeTYsxI+ZBBDGdODwIXLVtBhVR5+ayqpfUVic7dLjdrTixjF7AV1dYBEq88qBPAC YmR29vPie9vhmOEe3IxwKRx4ENqBRA2ZkeA5qqs4Z45U8oaT5m7DdbfJs3cWCE/ulBQ5 NkVDdRZOyZk2/yiTsODj6VbHm7wbOTCfKuvBEA9jJAQlUz5Fzc+YDVOnF7NNd2eZrUAx ObVQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1739838324; x=1740443124; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=8m1uQh6w5iYJ3orp8b5EeRdmeUvkTNV6vuD529TfFW8=; b=hVP0kFvOlXy2HzZDez3eL0OI8ykwdQMz/ClJrQP4YFFTyAMAmYydiVs3ourazYBrvO nUtkvrH9bxPvvCC4zLhprUxzADEwq3GO1lLe/NdgW2TOl/h3SznBRLxrgDq2HGzrVlLL h099/CiRTJJQ3YG3qgZRTfyzEj0+obzXN/LSHpo7JuZ5vwsiCEAv8pg+x3nXmayxAnJU bR2cZTQvK9RGfIztHCn5KYdHWQ6xqZsZJdgV9RyTeDCdjbIEoGWN1aC010m+emVK5wGp jtIpcGuq+x/Lop+NRlpwQLfDAxEBC38JC8pGDLuC1EQj0CI281RnPyfLUxWMDWaeDakv rrCA== X-Forwarded-Encrypted: i=1; AJvYcCUQhzQ7d+ZBZlwLxxqnXgMoJyxTEW8zgMidAVAX4KivWlX3FTN2yTd5sFJZayYR4HxpMgLamNGCTOv9@vger.kernel.org, AJvYcCVLxeDuZG+PAec04eWS/md+URjcnUIird3uk/wufWvyrs0pnw2kihpfGMZIGxEBURjRTc1jJnAKbJuIqqI=@vger.kernel.org, AJvYcCWcPe5nmirJjFkYlLiIdEvOvcV+w6mxrxpJVoJ8n9q+EZluBQrojEgBv+oKDbpXb19XzC7wJgim@vger.kernel.org X-Gm-Message-State: AOJu0Yyqe6um5SFMrpHYFeR7F7m+4uSIoW94XRMJB3rpCWceFJm6a5KB NLdmrajFDyIZgx8aRnRINivRbQJx7+f37RT7Mq2Meu5tk+EvSHxhWwVSqGRV X-Gm-Gg: ASbGnctH3ZtAgxrP18z11aBPAu8zVfkwuIJhQ2vQK8v3Myhqr4+hYe+mbw9oDIrFXyB n/XSdxIulHnHV4/U+mGrDwlKyPkYGCYog8KqXA+S6n0ncyqcEY5corucvq7zBw5WwcSvjCRycBz 8B4F0iPaK8mpEeRgdv6eZ8i6ZorYDwRHuSiMv2+URPjr5SxqdNh4YhUSxskmvu+HunlsNq7K3KL uadInXd9fJ++//OXQ/ctL32yqQuV+DtcWvG5U6FKLhSE44j3tnZdvzAy961G8YupXlxQR/eWu2e Dp3LmViaSAFkpVl/ X-Google-Smtp-Source: AGHT+IFEwVOQfWAk3usB+gCbjckJ1M+hXwhwG3/4LSm+JCb/QOyIiORIX6KA7JP7mO6j+vJj81w/qw== X-Received: by 2002:a05:600c:4f94:b0:439:4706:ae04 with SMTP id 5b1f17b1804b1-4396e7171b4mr123085705e9.16.1739838323483; Mon, 17 Feb 2025 16:25:23 -0800 (PST) Received: from qasdev.Home ([2a02:c7c:6696:8300:1981:9861:b731:66d5]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4395a1b84bcsm171982195e9.40.2025.02.17.16.25.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Feb 2025 16:25:23 -0800 (PST) From: Qasim Ijaz To: andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, syzbot , stable@vger.kernel.org Subject: [PATCH] net: fix uninitialised access in mii_nway_restart() Date: Tue, 18 Feb 2025 00:24:43 +0000 Message-Id: <20250218002443.11731-1-qasdev00@gmail.com> X-Mailer: git-send-email 2.39.5 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org In mii_nway_restart() during the line: bmcr = mii->mdio_read(mii->dev, mii->phy_id, MII_BMCR); The code attempts to call mii->mdio_read which is ch9200_mdio_read(). ch9200_mdio_read() utilises a local buffer, which is initialised with control_read(): unsigned char buff[2]; However buff is conditionally initialised inside control_read(): if (err == size) { memcpy(data, buf, size); } If the condition of "err == size" is not met, then buff remains uninitialised. Once this happens the uninitialised buff is accessed and returned during ch9200_mdio_read(): return (buff[0] | buff[1] << 8); The problem stems from the fact that ch9200_mdio_read() ignores the return value of control_read(), leading to uinit-access of buff. To fix this we should check the return value of control_read() and return early on error. Signed-off-by: Qasim Ijaz Reported-by: syzbot Tested-by: syzbot Closes: https://syzkaller.appspot.com/bug?extid=3361c2d6f78a3e0892f9 Fixes: 4a476bd6d1d9 ("usbnet: New driver for QinHeng CH9200 devices") Cc: stable@vger.kernel.org --- drivers/net/mii.c | 2 ++ drivers/net/usb/ch9200.c | 7 +++++-- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/net/mii.c b/drivers/net/mii.c index 37bc3131d31a..e305bf0f1d04 100644 --- a/drivers/net/mii.c +++ b/drivers/net/mii.c @@ -464,6 +464,8 @@ int mii_nway_restart (struct mii_if_info *mii) /* if autoneg is off, it's an error */ bmcr = mii->mdio_read(mii->dev, mii->phy_id, MII_BMCR); + if (bmcr < 0) + return bmcr; if (bmcr & BMCR_ANENABLE) { bmcr |= BMCR_ANRESTART; diff --git a/drivers/net/usb/ch9200.c b/drivers/net/usb/ch9200.c index f69d9b902da0..e32d3c282dc1 100644 --- a/drivers/net/usb/ch9200.c +++ b/drivers/net/usb/ch9200.c @@ -178,6 +178,7 @@ static int ch9200_mdio_read(struct net_device *netdev, int phy_id, int loc) { struct usbnet *dev = netdev_priv(netdev); unsigned char buff[2]; + int ret; netdev_dbg(netdev, "%s phy_id:%02x loc:%02x\n", __func__, phy_id, loc); @@ -185,8 +186,10 @@ static int ch9200_mdio_read(struct net_device *netdev, int phy_id, int loc) if (phy_id != 0) return -ENODEV; - control_read(dev, REQUEST_READ, 0, loc * 2, buff, 0x02, - CONTROL_TIMEOUT_MS); + ret = control_read(dev, REQUEST_READ, 0, loc * 2, buff, 0x02, + CONTROL_TIMEOUT_MS); + if (ret != 2) + return ret < 0 ? ret : -EINVAL; return (buff[0] | buff[1] << 8); }