Mitre assigned CVE-2023-23559 for this.
On Tue, 2023-01-10 at 18:30 +0100, Szymon Heidrich wrote:
> Since resplen and respoffs are signed integers sufficiently
> large values of unsigned int len and offset members of RNDIS
> response will result in negative values of prior variables.
> This may be utilized to bypass implemented security checks
> to either extract memory contents by manipulating offset or
> overflow the data buffer via memcpy by manipulating both
> offset and len.
>
> Additionally assure that sum of resplen and respoffs does not
> overflow so buffer boundaries are kept.
>
> Fixes: 80f8c5b434f9 ("rndis_wlan: copy only useful data from
> rndis_command respond")
> Signed-off-by: Szymon Heidrich <szymon.heidrich@xxxxxxxxx>
> ---
> drivers/net/wireless/rndis_wlan.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/wireless/rndis_wlan.c
> b/drivers/net/wireless/rndis_wlan.c
> index 82a7458e0..d7fc05328 100644
> --- a/drivers/net/wireless/rndis_wlan.c
> +++ b/drivers/net/wireless/rndis_wlan.c
> @@ -697,7 +697,7 @@ static int rndis_query_oid(struct usbnet *dev,
> u32 oid, void *data, int *len)
> struct rndis_query_c *get_c;
> } u;
> int ret, buflen;
> - int resplen, respoffs, copylen;
> + u32 resplen, respoffs, copylen;
>
> buflen = *len + sizeof(*u.get);
> if (buflen < CONTROL_BUFFER_SIZE)
> @@ -740,7 +740,7 @@ static int rndis_query_oid(struct usbnet *dev,
> u32 oid, void *data, int *len)
> goto exit_unlock;
> }
>
> - if ((resplen + respoffs) > buflen) {
> + if (resplen > (buflen - respoffs)) {
> /* Device would have returned more data if
> buffer would
> * have been big enough. Copy just the bits
> that we got.
> */
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