From patchwork Wed Jul 24 01:15:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ma Ke X-Patchwork-Id: 13740527 Received: from cstnet.cn (smtp21.cstnet.cn [159.226.251.21]) (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 C393E23B1; Wed, 24 Jul 2024 01:16:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.21 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721783788; cv=none; b=j3QNzPEfNKdLkUDPsXrHdMO8xu8m/1fre49NTOCmdmX9cO7pRK/Q6bd76iMv1HO94W89sAvCQGS9iX0stbMdszVX9dLIjREGF+cCSqoRuZWyGf2KBBfakVzNpDVqifotMSwy9i1aF23TDBPOQawubLEeq1HlrZIIdN+fZSD3dJc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721783788; c=relaxed/simple; bh=NF40QjUIzoD6FOsKo0ZbfmOJMF5vcyagGqDfrmVwfJk=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=a/TgNJuw6vknlKcVJrVIom9v797ysIDEFFM44s6fonKbNLBbsInWYh1VFHKtDjgtC0uPcMcFj9iNAaz/mq/2TvWwncET2SmVIiw2J39XQ6OvnGnpkJnw29ux8QwKl7XKMjGvF4lsoxHqn2iNgAGxfM5vTXGd4PcnIKa2xsILHII= 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=159.226.251.21 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-01 (Coremail) with SMTP id qwCowAB3fUnMVaBmBtutAA--.40410S2; Wed, 24 Jul 2024 09:16:05 +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 Cc: linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 net] net: usb: sr9700: fix uninitialized variable use in sr_mdio_read Date: Wed, 24 Jul 2024 09:15:54 +0800 Message-Id: <20240724011554.1445989-1-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: qwCowAB3fUnMVaBmBtutAA--.40410S2 X-Coremail-Antispam: 1UD129KBjvJXoW7CF15XFyrCr4kZr4DuF45Jrb_yoW8GF48pr 4fWa9YyrWUJa47Z3ykXws7W3WFkwsYgFy3GFW8Gw1fZrZ5JFn5C34FgFyjgw1UGrZ8Jay2 va1qyFWfXa1YvaUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvK14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r4j6ryUM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVCY1x0267AKxVW8JV W8Jr1lnxkEFVAIw20F6cxK64vIFxWle2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xv F2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r 4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I 648v4I1lc7CjxVAaw2AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7 v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF 1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIx AIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI 42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r1j6r4UYxBIdaVFxh VjvjDU0xZFpf9x0JUQvtAUUUUU= 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. This can be avoided by checking the return value of sr_share_read_word and propagating the error if the read operation failed. Found by code review. Fixes: c9b37458e956 ("USB2NET : SR9700 : One chip USB 1.1 USB2NET SR9700Device Driver Support") Signed-off-by: Ma Ke --- Changes in v2: - modified the subject as suggestions. --- drivers/net/usb/sr9700.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c index 0a662e42ed96..d5bc596f4521 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"); @@ -193,7 +194,10 @@ static int sr_mdio_read(struct net_device *netdev, int phy_id, int loc) 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