From 66cf4f582987af3f5cd3a62cd85a6922411d73c6 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 2 Mar 2021 14:19:39 +0300 Subject: [PATCH] staging: ks7010: prevent buffer overflow in ks_wlan_set_scan() commit e163b9823a0b08c3bb8dc4f5b4b5c221c24ec3e5 upstream. The user can specify a "req->essid_len" of up to 255 but if it's over IW_ESSID_MAX_SIZE (32) that can lead to memory corruption. Fixes: 13a9930d15b4 ("staging: ks7010: add driver from Nanonote extra-repository") Signed-off-by: Dan Carpenter Cc: stable Link: https://lore.kernel.org/r/YD4fS8+HmM/Qmrw6@mwanda Signed-off-by: Greg Kroah-Hartman --- drivers/staging/ks7010/ks_wlan_net.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/staging/ks7010/ks_wlan_net.c b/drivers/staging/ks7010/ks_wlan_net.c index dc09cc6..09e7b4c 100644 --- a/drivers/staging/ks7010/ks_wlan_net.c +++ b/drivers/staging/ks7010/ks_wlan_net.c @@ -1120,6 +1120,7 @@ static int ks_wlan_set_scan(struct net_device *dev, { struct ks_wlan_private *priv = netdev_priv(dev); struct iw_scan_req *req = NULL; + int len; if (priv->sleep_mode == SLP_SLEEP) return -EPERM; @@ -1129,8 +1130,9 @@ static int ks_wlan_set_scan(struct net_device *dev, if (wrqu->data.length == sizeof(struct iw_scan_req) && wrqu->data.flags & IW_SCAN_THIS_ESSID) { req = (struct iw_scan_req *)extra; - priv->scan_ssid_len = req->essid_len; - memcpy(priv->scan_ssid, req->essid, priv->scan_ssid_len); + len = min_t(int, req->essid_len, IW_ESSID_MAX_SIZE); + priv->scan_ssid_len = len; + memcpy(priv->scan_ssid, req->essid, len); } else { priv->scan_ssid_len = 0; } -- 2.7.4