staging/rtl8192e: Remove all strcpy() uses

strcpy() performs no bounds checking on the destination buffer. This
could result in linear overflows beyond the end of the buffer, leading
to all kinds of misbehaviors. The safe replacement is strscpy().

It is also dangerous a strcpy() followed by a strcat(). In this case,
refactor the code using scnprintf() and avoid this combination.

Signed-off-by: Len Baker <len.baker@gmx.com>
Link: https://lore.kernel.org/r/20210723173216.12157-1-len.baker@gmx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/rtl8192e/rtl8192e/r8192E_dev.c b/drivers/staging/rtl8192e/rtl8192e/r8192E_dev.c
index b626ac4..358b629 100644 (file)
--- a/drivers/staging/rtl8192e/rtl8192e/r8192E_dev.c
+++ b/drivers/staging/rtl8192e/rtl8192e/r8192E_dev.c
@@ -2167,7 +2167,7 @@ rtl92e_init_variables(struct net_device  *dev)
 {
        struct r8192_priv *priv = rtllib_priv(dev);
 
-       strcpy(priv->nick, "rtl8192E");
+       strscpy(priv->nick, "rtl8192E", sizeof(priv->nick));
 
        priv->rtllib->softmac_features  = IEEE_SOFTMAC_SCAN |
                IEEE_SOFTMAC_ASSOCIATE | IEEE_SOFTMAC_PROBERQ |

diff --git a/drivers/staging/rtl8192e/rtllib_softmac.c b/drivers/staging/rtl8192e/rtllib_softmac.c
index 25b3d39..d2726d0 100644 (file)
--- a/drivers/staging/rtl8192e/rtllib_softmac.c
+++ b/drivers/staging/rtl8192e/rtllib_softmac.c
@@ -2582,7 +2582,8 @@ static void rtllib_start_ibss_wq(void *data)
        mutex_lock(&ieee->wx_mutex);
 
        if (ieee->current_network.ssid_len == 0) {
-               strcpy(ieee->current_network.ssid, RTLLIB_DEFAULT_TX_ESSID);
+               strscpy(ieee->current_network.ssid, RTLLIB_DEFAULT_TX_ESSID,
+                       sizeof(ieee->current_network.ssid));
                ieee->current_network.ssid_len = strlen(RTLLIB_DEFAULT_TX_ESSID);
                ieee->ssid_set = 1;
        }

diff --git a/drivers/staging/rtl8192e/rtllib_softmac_wx.c b/drivers/staging/rtl8192e/rtllib_softmac_wx.c
index f89799d..57a6d11 100644 (file)
--- a/drivers/staging/rtl8192e/rtllib_softmac_wx.c
+++ b/drivers/staging/rtl8192e/rtllib_softmac_wx.c
@@ -539,18 +539,14 @@ int rtllib_wx_set_rawtx(struct rtllib_device *ieee,
 }
 EXPORT_SYMBOL(rtllib_wx_set_rawtx);
 
-int rtllib_wx_get_name(struct rtllib_device *ieee,
-                            struct iw_request_info *info,
-                            union iwreq_data *wrqu, char *extra)
+int rtllib_wx_get_name(struct rtllib_device *ieee, struct iw_request_info *info,
+                      union iwreq_data *wrqu, char *extra)
 {
-       strcpy(wrqu->name, "802.11");
-
-       if (ieee->modulation & RTLLIB_CCK_MODULATION)
-               strcat(wrqu->name, "b");
-       if (ieee->modulation & RTLLIB_OFDM_MODULATION)
-               strcat(wrqu->name, "g");
-       if (ieee->mode & (IEEE_N_24G | IEEE_N_5G))
-               strcat(wrqu->name, "n");
+       const char *b = ieee->modulation & RTLLIB_CCK_MODULATION ? "b" : "";
+       const char *g = ieee->modulation & RTLLIB_OFDM_MODULATION ? "g" : "";
+       const char *n = ieee->mode & (IEEE_N_24G | IEEE_N_5G) ? "n" : "";
+
+       scnprintf(wrqu->name, sizeof(wrqu->name), "802.11%s%s%s", b, g, n);
        return 0;
 }
 EXPORT_SYMBOL(rtllib_wx_get_name);