staging/rtl8192e: Remove all strcpy() uses in favor of strscpy()

PATCH In review Len Baker 2 participants 3 messages Jul 18, 2021 – Jul 23, 2021 Staging

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Len Baker

author

2021-07-18 09:07 UTC #0 lore raw

PATCH 1/1 staging/rtl8192e: Remove all strcpy() uses in favor of strscpy()

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().

Signed-off-by Len Baker <[email protected]>

---
 drivers/staging/rtl8192e/rtl8192e/r8192E_dev.c | 2 +-
 drivers/staging/rtl8192e/rtllib_softmac.c      | 3 ++-
 drivers/staging/rtl8192e/rtllib_softmac_wx.c   | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

drivers/staging/rtl8192e/rtl8192e/r8192E_dev.c +1 -1

index b626ac45db80..358b629d2cc6 100644
@@ -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 |

drivers/staging/rtl8192e/rtllib_softmac.c +2 -1

index 25b3d3950a3c..d2726d01c757 100644
@@ -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;
 	}

drivers/staging/rtl8192e/rtllib_softmac_wx.c +1 -1

index f89799d43b1b..5968407c646d 100644
@@ -543,7 +543,7 @@ 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");
+	strscpy(wrqu->name, "802.11", sizeof(wrqu->name));
 
 	if (ieee->modulation & RTLLIB_CCK_MODULATION)
 		strcat(wrqu->name, "b");

--
2.25.1

Dan Carpenter

2021-07-19 05:44 UTC #1 lore raw

drivers/staging/rtl8192e/rtllib_softmac_wx.c int rtllib_wx_get_name(struct rtllib_device *ieee, · line 549

Quoted 13 lines · Len Baker

drivers/staging/rtl8192e/rtllib_softmac_wx.c +1 -1

index f89799d43b1b..5968407c646d 100644
@@ -543,7 +543,7 @@ 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");
+	strscpy(wrqu->name, "802.11", sizeof(wrqu->name));
 
 	if (ieee->modulation & RTLLIB_CCK_MODULATION)
 		strcat(wrqu->name, "b");

This patch is just about silencing inferior static analysis tools, right? Most checkers can figure out the size of the array and verify that it has space for "802.11". Probably it's only raw grep which can't.

It doesn't make sense to me that we have strscpy() followed by strcat. So let's fix both.

regards,
dan carpenter

Len Baker

author

2021-07-23 16:31 UTC #2 lore raw

Hi,

Quoted 20 lines · Dan Carpenter

drivers/staging/rtl8192e/rtllib_softmac_wx.c int rtllib_wx_get_name(struct rtllib_device *ieee, · line 549
Quoted 13 lines · Len Baker
drivers/staging/rtl8192e/rtllib_softmac_wx.c +1 -1
index f89799d43b1b..5968407c646d 100644
@@ -543,7 +543,7 @@ 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");
+	strscpy(wrqu->name, "802.11", sizeof(wrqu->name));
 
 	if (ieee->modulation & RTLLIB_CCK_MODULATION)
 		strcat(wrqu->name, "b");
This patch is just about silencing inferior static analysis tools, right? Most checkers can figure out the size of the array and verify that it has space for "802.11". Probably it's only raw grep which can't.

Quoted 2 lines

It doesn't make sense to me that we have strscpy() followed by strcat. So let's fix both.

Ok, I will send a v2 for review. Thanks for the feedback.

Quoted 3 lines

regards,
dan carpenter

Regards,
Len