From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Tue, 1 Mar 2022 08:04:24 +0000 (+0300)
Subject: usb: gadget: rndis: prevent integer overflow in rndis_set_response()
X-Git-Tag: v5.15.73~6278
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=56b38e3ca4064041d93c1ca18828c8cedad2e16c;p=platform%2Fkernel%2Flinux-rpi.git

usb: gadget: rndis: prevent integer overflow in rndis_set_response()

commit 65f3324f4b6fed78b8761c3b74615ecf0ffa81fa upstream.

If "BufOffset" is very large the "BufOffset + 8" operation can have an
integer overflow.

Cc: stable@kernel.org
Fixes: 38ea1eac7d88 ("usb: gadget: rndis: check size of RNDIS_MSG_SET command")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20220301080424.GA17208@kili
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/gadget/function/rndis.c b/drivers/usb/gadget/function/rndis.c
index 0f14c52..4150de9 100644
--- a/drivers/usb/gadget/function/rndis.c
+++ b/drivers/usb/gadget/function/rndis.c
@@ -640,6 +640,7 @@ static int rndis_set_response(struct rndis_params *params,
 	BufLength = le32_to_cpu(buf->InformationBufferLength);
 	BufOffset = le32_to_cpu(buf->InformationBufferOffset);
 	if ((BufLength > RNDIS_MAX_TOTAL_SIZE) ||
+	    (BufOffset > RNDIS_MAX_TOTAL_SIZE) ||
 	    (BufOffset + 8 >= RNDIS_MAX_TOTAL_SIZE))
 		    return -EINVAL;