usb: rndis_host: Secure rndis_query check against int overflow
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 <szymon.heidrich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
7dc6183854
commit
c7dd13805f
@ -255,7 +255,8 @@ 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)
|
||||
|
Loading…
x
Reference in New Issue
Block a user