From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 682D3C433FE for ; Tue, 1 Mar 2022 20:26:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234263AbiCAU1H (ORCPT ); Tue, 1 Mar 2022 15:27:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239235AbiCAUYh (ORCPT ); Tue, 1 Mar 2022 15:24:37 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 039992715; Tue, 1 Mar 2022 12:22:27 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6189560C1E; Tue, 1 Mar 2022 20:22:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 47531C340EF; Tue, 1 Mar 2022 20:22:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646166146; bh=4D4dbyGkdRwtaAw9y25zBM3qrwnZWcTagBLefzKVXZU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Xa3pOiKt3/mqHocfrmqHQWdDyO+1xHPX6M5+kRPVZkYOW62HvOdA32PY5hfmVm2Uc JY0pkUGgk6r//XLl8ZTaJFuUVgTP770ppIJrdZ24IyPzHAEVMMhJF/rLLjBjF4xjhY CI6eoxvS0L2k9Gr3y63XKqodhq6kni/zgpVxSFg+NP70KNBq9e1qQteB1+uZ1Er/b+ j6f2qB30RSQyBcFLLszmAWFfW0+IRy5tIkuqzW/HJOsVLIFu33EiAfrITvvFbsudhp zrwlNzukYrfLznhXuYCTPzMB4Z+LL4b6JzD4biDGygiubtqNM7mpi7TopCcvgyZs1d 5l0ksh6sl4rFQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Oliver Neukum , Grant Grundler , "David S . Miller" , Sasha Levin , kuba@kernel.org, andrew@lunn.ch, arnd@arndb.de, linux-usb@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 2/6] sr9700: sanity check for packet length Date: Tue, 1 Mar 2022 15:22:06 -0500 Message-Id: <20220301202212.19419-2-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220301202212.19419-1-sashal@kernel.org> References: <20220301202212.19419-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Oliver Neukum [ Upstream commit e9da0b56fe27206b49f39805f7dcda8a89379062 ] A malicious device can leak heap data to user space providing bogus frame lengths. Introduce a sanity check. Signed-off-by: Oliver Neukum Reviewed-by: Grant Grundler Signed-off-by: David S. Miller 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 aadfe1d1c37ee..f4c4df01874c3 100644 --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -409,7 +409,7 @@ 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) + if (len > ETH_FRAME_LEN || len > skb->len) return 0; /* the last packet of current skb */ -- 2.34.1