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 40FD76FA0 for ; Mon, 16 Jan 2023 17:15:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC0D0C433D2; Mon, 16 Jan 2023 17:15:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1673889323; bh=7uvtiZsQiXByGYzrT7Kbuh0ZMO6iIueX7kjfodR6j/E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ovqilD4Jo4ZP85L8AHx+5oqueVzbyBeFWoHIIW6qk1vmqIA4ziZjrOrfTJfszWGIp Jj8pJUmVblBGqCDFZcCjBrqgXaQr09XUzH24PgNqD1IJtkw6+1YhGr96g8nu/6sZ32 o/l0MMCH5+PoAHQ1tV3ENs0WMb5CI2hB7CbEVM9g= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Szymon Heidrich , "David S. Miller" , Sasha Levin Subject: [PATCH 4.14 314/338] usb: rndis_host: Secure rndis_query check against int overflow Date: Mon, 16 Jan 2023 16:53:07 +0100 Message-Id: <20230116154834.817877049@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230116154820.689115727@linuxfoundation.org> References: <20230116154820.689115727@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 c7dd13805f8b8fc1ce3b6d40f6aff47e66b72ad2 ] Variables off and len typed as uint32 in rndis_query function are controlled by incoming RNDIS response message thus their value may be manipulated. Setting off to a unexpectetly large value will cause the sum with len and 8 to overflow and pass the implemented validation step. Consequently the response pointer will be referring to a location past the expected buffer boundaries allowing information leakage e.g. via RNDIS_OID_802_3_PERMANENT_ADDRESS OID. Fixes: ddda08624013 ("USB: rndis_host, various cleanups") Signed-off-by: Szymon Heidrich Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/usb/rndis_host.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/rndis_host.c b/drivers/net/usb/rndis_host.c index ab41a63aa4aa..497d6bcdc276 100644 --- a/drivers/net/usb/rndis_host.c +++ b/drivers/net/usb/rndis_host.c @@ -267,7 +267,8 @@ static int rndis_query(struct usbnet *dev, struct usb_interface *intf, off = le32_to_cpu(u.get_c->offset); len = le32_to_cpu(u.get_c->len); - if (unlikely((8 + off + len) > CONTROL_BUFFER_SIZE)) + if (unlikely((off > CONTROL_BUFFER_SIZE - 8) || + (len > CONTROL_BUFFER_SIZE - 8 - off))) goto response_error; if (*reply_len != -1 && len != *reply_len) -- 2.35.1