From: Dan Aloni <dan@aloni.org>
Date: Sat, 20 Jun 2009 13:32:22 +0000 (+0300)
Subject: Staging: prevent rtl8187se from crashing dev_ioctl() in SIOCGIWNAME
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=02c8baecf5d8850dba40b47cdf003ed2e04e66dd;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

Staging: prevent rtl8187se from crashing dev_ioctl() in SIOCGIWNAME

I repeatedly get __stack_chk_fail panic()s with this driver before
applying the attached fix.

ieee80211_wx_get_name() ignores sizeof(wrqu->name) which is IFNAMSIZ (16), and
on certain conditions, the concatenated string will be larger than IFNAMSIZ
including the terminating zero.

    length ("802.11" ++ "b" ++ "/g" ++ " linked" ++ "\x00") == 17

This fix uses strl{cpy,cat} in addition to the reduction of the total
possible length of the output string by a char.

It can be applied to 2.6.30-stable as well.

Signed-off-by: Dan Aloni <dan@aloni.org>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/staging/rtl8187se/ieee80211/ieee80211_softmac_wx.c b/drivers/staging/rtl8187se/ieee80211/ieee80211_softmac_wx.c
index 93af37e2d31a..54b4b718f84a 100644
--- a/drivers/staging/rtl8187se/ieee80211/ieee80211_softmac_wx.c
+++ b/drivers/staging/rtl8187se/ieee80211/ieee80211_softmac_wx.c
@@ -461,19 +461,19 @@ int ieee80211_wx_get_name(struct ieee80211_device *ieee,
 			     struct iw_request_info *info,
 			     union iwreq_data *wrqu, char *extra)
 {
-	strcpy(wrqu->name, "802.11");
+	strlcpy(wrqu->name, "802.11", IFNAMSIZ);
 	if(ieee->modulation & IEEE80211_CCK_MODULATION){
-		strcat(wrqu->name, "b");
+		strlcat(wrqu->name, "b", IFNAMSIZ);
 		if(ieee->modulation & IEEE80211_OFDM_MODULATION)
-			strcat(wrqu->name, "/g");
+			strlcat(wrqu->name, "/g", IFNAMSIZ);
 	}else if(ieee->modulation & IEEE80211_OFDM_MODULATION)
-		strcat(wrqu->name, "g");
+		strlcat(wrqu->name, "g", IFNAMSIZ);
 
 	if((ieee->state == IEEE80211_LINKED) ||
 		(ieee->state == IEEE80211_LINKED_SCANNING))
-		strcat(wrqu->name," linked");
+		strlcat(wrqu->name,"  link", IFNAMSIZ);
 	else if(ieee->state != IEEE80211_NOLINK)
-		strcat(wrqu->name," link..");
+		strlcat(wrqu->name," .....", IFNAMSIZ);
 
 
 	return 0;