From: Zhang Xiaohui <ruc_zhangxiaohui@xxxxxxx> [ Upstream commit 5c455c5ab332773464d02ba17015acdca198f03d ] mwifiex_cmd_802_11_ad_hoc_start() calls memcpy() without checking the destination size may trigger a buffer overflower, which a local user could use to cause denial of service or the execution of arbitrary code. Fix it by putting the length check before calling memcpy(). Signed-off-by: Zhang Xiaohui <ruc_zhangxiaohui@xxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20201206084801.26479-1-ruc_zhangxiaohui@xxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/wireless/marvell/mwifiex/join.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/wireless/marvell/mwifiex/join.c b/drivers/net/wireless/marvell/mwifiex/join.c index d87aeff70cefb..c2cb1e711c06e 100644 --- a/drivers/net/wireless/marvell/mwifiex/join.c +++ b/drivers/net/wireless/marvell/mwifiex/join.c @@ -877,6 +877,8 @@ mwifiex_cmd_802_11_ad_hoc_start(struct mwifiex_private *priv, memset(adhoc_start->ssid, 0, IEEE80211_MAX_SSID_LEN); + if (req_ssid->ssid_len > IEEE80211_MAX_SSID_LEN) + req_ssid->ssid_len = IEEE80211_MAX_SSID_LEN; memcpy(adhoc_start->ssid, req_ssid->ssid, req_ssid->ssid_len); mwifiex_dbg(adapter, INFO, "info: ADHOC_S_CMD: SSID = %s\n", -- 2.27.0