From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> [ Upstream commit 87f86cddda65cab8a7e3df8a00e16abeccaa0730 ] We need to cap "ssidlen" to prevent a memcpy() overflow. Fixes: 40115bbc40e2 ("staging: wfx: implement the rest of mac80211 API") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Reviewed-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> Link: https://lore.kernel.org/r/20200424104235.GA416402@mwanda Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/staging/wfx/sta.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/staging/wfx/sta.c b/drivers/staging/wfx/sta.c index 9d430346a58b..969d7a4a7fbd 100644 --- a/drivers/staging/wfx/sta.c +++ b/drivers/staging/wfx/sta.c @@ -520,7 +520,9 @@ static void wfx_do_join(struct wfx_vif *wvif) ssidie = ieee80211_bss_get_ie(bss, WLAN_EID_SSID); if (ssidie) { ssidlen = ssidie[1]; - memcpy(ssid, &ssidie[2], ssidie[1]); + if (ssidlen > IEEE80211_MAX_SSID_LEN) + ssidlen = IEEE80211_MAX_SSID_LEN; + memcpy(ssid, &ssidie[2], ssidlen); } rcu_read_unlock(); -- 2.25.1