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 7D7C41FB4 for ; Fri, 3 Feb 2023 10:14:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA19BC4339C; Fri, 3 Feb 2023 10:14:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1675419266; bh=WkuS7BOoi9PcVasEkDtkmpqciy4LAk+jx3KfLC2u2Tw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Il0kR3emNc6Yrzn6kWAUSXyLsCEdU3LQrt8zaiQ344vuvL34Mv1LdouXl22+/0GnN sdfu6b5pZcjaf1A13PG26EjU2chCR6WV5rtenQUoUjqDdVdl2eV16A9LNucwSBv/O9 dq90L89uiGO7GUkp80Re+lAk/isKNtxvLMQBtyK8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Szymon Heidrich , Paolo Abeni , Sasha Levin Subject: [PATCH 4.14 12/62] net: usb: sr9700: Handle negative len Date: Fri, 3 Feb 2023 11:12:08 +0100 Message-Id: <20230203101013.530773905@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230203101012.959398849@linuxfoundation.org> References: <20230203101012.959398849@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Szymon Heidrich [ Upstream commit ecf7cf8efb59789e2b21d2f9ab926142579092b2 ] Packet len computed as difference of length word extracted from skb data and four may result in a negative value. In such case processing of the buffer should be interrupted rather than setting sr_skb->len to an unexpectedly large value (due to cast from signed to unsigned integer) and passing sr_skb to usbnet_skb_return. Fixes: e9da0b56fe27 ("sr9700: sanity check for packet length") Signed-off-by: Szymon Heidrich Link: https://lore.kernel.org/r/20230114182326.30479-1-szymon.heidrich@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- drivers/net/usb/sr9700.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c index a97dd62b9d54..dbdb027abe47 100644 --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -410,7 +410,7 @@ static int sr9700_rx_fixup(struct usbnet *dev, struct sk_buff *skb) /* ignore the CRC length */ len = (skb->data[1] | (skb->data[2] << 8)) - 4; - if (len > ETH_FRAME_LEN || len > skb->len) + if (len > ETH_FRAME_LEN || len > skb->len || len < 0) return 0; /* the last packet of current skb */ -- 2.39.0