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 581D85683 for ; Mon, 3 Apr 2023 14:14:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D03ADC433D2; Mon, 3 Apr 2023 14:14:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680531297; bh=rUQRIhUeyifgt0ybj9cSWK6h7SZ7CgQcMts4G2oQ0Rc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jlXbGeBEhiwB+xl+Pg/D0QMZuNtTvIRBqyb3EnyKMblsdTw7qMveGdIaSoqUpDH5r f4PwxNnhkWU05LL8jVMv+AtVMtzOWC3jzi4DrqjnMHsiRBkZJ2MrwHTNduruFdFNdI vC2LOsWyBg/ayUoeKzvYcK6xZ259acn9sRApQsuo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Szymon Heidrich , Jakub Kicinski , Sasha Levin Subject: [PATCH 4.19 10/84] net: usb: smsc95xx: Limit packet length to skb->len Date: Mon, 3 Apr 2023 16:08:11 +0200 Message-Id: <20230403140353.748065745@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230403140353.406927418@linuxfoundation.org> References: <20230403140353.406927418@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 ff821092cf02a70c2bccd2d19269f01e29aa52cf ] Packet length retrieved from descriptor may be larger than the actual socket buffer length. In such case the cloned skb passed up the network stack will leak kernel memory contents. Fixes: 2f7ca802bdae ("net: Add SMSC LAN9500 USB2.0 10/100 ethernet adapter driver") Signed-off-by: Szymon Heidrich Reviewed-by: Jakub Kicinski Link: https://lore.kernel.org/r/20230316101954.75836-1-szymon.heidrich@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/usb/smsc95xx.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index 4f29010e1aeff..0850486864135 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -1950,6 +1950,12 @@ static int smsc95xx_rx_fixup(struct usbnet *dev, struct sk_buff *skb) size = (u16)((header & RX_STS_FL_) >> 16); align_count = (4 - ((size + NET_IP_ALIGN) % 4)) % 4; + if (unlikely(size > skb->len)) { + netif_dbg(dev, rx_err, dev->net, + "size err header=0x%08x\n", header); + return 0; + } + if (unlikely(header & RX_STS_ES_)) { netif_dbg(dev, rx_err, dev->net, "Error header=0x%08x\n", header); -- 2.39.2