From patchwork Thu Jul 25 02:29:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ma Ke X-Patchwork-Id: 814568 Received: from cstnet.cn (smtp84.cstnet.cn [159.226.251.84]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8C0DD63D0; Thu, 25 Jul 2024 02:30:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.84 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721874609; cv=none; b=APGfn1LouXWiFepe0RpBoRJQr3SvDCJnprCbppHsMgvKLDJk11ESlROXR8cbBBRVPNttOZJEWcD75asnDIpukDKhHWLBFg5lels+7Gb/AiCew1qdWWTwql/x/H8hjL6B/roNigp59o0xVQquyCVRF7jwnY1RxZ5rslm1j1qkSc8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721874609; c=relaxed/simple; bh=UflBeGAI8Ewd2P0gL0BG4VcOuURnvNeNQ1BGv2VbtmI=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=NxX2wm9ar8h1OGXVtr3pwU+oCcJT5jvTEN7giyTwYsViiJTBaZ2zYgzTsrB+VDvysCd0EMj0jMdmzuj/FltNmilphrv4wAjEcZJh5d9jUP8D816U8EsLp8tReGfb3KGDK0YGhYNDtWezL26TU2EJrX0NUHl6HGv+JluOSWRPhvo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.84 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from icess-ProLiant-DL380-Gen10.. (unknown [183.174.60.14]) by APP-05 (Coremail) with SMTP id zQCowACnEUGXuKFm2O7cAA--.57002S2; Thu, 25 Jul 2024 10:29:50 +0800 (CST) From: Ma Ke To: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, make24@iscas.ac.cn, liujunliang_ljl@163.com, syoshida@redhat.com, andrew@lunn.ch, horms@kernel.org Cc: linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH net v4] net: usb: sr9700: fix uninitialized variable use in sr_mdio_read Date: Thu, 25 Jul 2024 10:29:42 +0800 Message-Id: <20240725022942.1720199-1-make24@iscas.ac.cn> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: zQCowACnEUGXuKFm2O7cAA--.57002S2 X-Coremail-Antispam: 1UD129KBjvJXoW7CF15XFyrCr4kuryfCF1kAFb_yoW8AF1fpr 47Ga90yrWUJ347Z3ykXw1vg3WFkw4kKay3W348Gw1fZ395Arn5C34FgFyYgw1UGrW5Aa12 qF4qvFWxua10vaUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBa14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r4j6ryUM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gr 1j6F4UJwAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40E FcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr 0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8v x2IErcIFxwACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAI cVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2js IEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUQvtAUUUUU= X-CM-SenderInfo: ppdnvj2u6l2u1dvotugofq/ It could lead to error happen because the variable res is not updated if the call to sr_share_read_word returns an error. In this particular case error code was returned and res stayed uninitialized. Same issue also applies to sr_read_reg. This can be avoided by checking the return value of sr_share_read_word and sr_read_reg, and propagating the error if the read operation failed. Found by code review. Cc: stable@vger.kernel.org Fixes: c9b37458e956 ("USB2NET : SR9700 : One chip USB 1.1 USB2NET SR9700Device Driver Support") Signed-off-by: Ma Ke --- Changes in v4: - added a check for sr_read_reg() as suggestions. Changes in v3: - added Cc stable line as suggestions. Changes in v2: - modified the subject as suggestions. --- drivers/net/usb/sr9700.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c index 0a662e42ed96..cb7d2f798fb4 100644 --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -179,6 +179,7 @@ static int sr_mdio_read(struct net_device *netdev, int phy_id, int loc) struct usbnet *dev = netdev_priv(netdev); __le16 res; int rc = 0; + int err; if (phy_id) { netdev_dbg(netdev, "Only internal phy supported\n"); @@ -189,11 +190,17 @@ static int sr_mdio_read(struct net_device *netdev, int phy_id, int loc) if (loc == MII_BMSR) { u8 value; - sr_read_reg(dev, SR_NSR, &value); + err = sr_read_reg(dev, SR_NSR, &value); + if (err < 0) + return err; + if (value & NSR_LINKST) rc = 1; } - sr_share_read_word(dev, 1, loc, &res); + err = sr_share_read_word(dev, 1, loc, &res); + if (err < 0) + return err; + if (rc == 1) res = le16_to_cpu(res) | BMSR_LSTATUS; else