mwifiex: prevent an array overflow

[ Upstream commit b4c35c17227fe437ded17ce683a6927845f8c4a4 ]

The "rate_index" is only used as an index into the phist_data->rx_rate[]
array in the mwifiex_hist_data_set() function.  That array has
MWIFIEX_MAX_AC_RX_RATES (74) elements and it's used to generate some
debugfs information.  The "rate_index" variable comes from the network
skb->data[] and it is a u8 so it's in the 0-255 range.  We need to cap
it to prevent an array overflow.

Fixes: cbf6e05527 ("mwifiex: add rx histogram statistics support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Dan Carpenter 2019-04-04 11:44:23 +03:00 committed by Greg Kroah-Hartman
parent 4b24af0936
commit af2fb022b3

View file

@ -533,5 +533,8 @@ u8 mwifiex_adjust_data_rate(struct mwifiex_private *priv,
rate_index = (rx_rate > MWIFIEX_RATE_INDEX_OFDM0) ?
rx_rate - 1 : rx_rate;
if (rate_index >= MWIFIEX_MAX_AC_RX_RATES)
rate_index = MWIFIEX_MAX_AC_RX_RATES - 1;
return rate_index;
}