leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

cfg80211: wext: avoid copying malformed SSIDs

Browse Source 
Ensure the SSID element is bounds-checked prior to invoking memcpy()
with its length field, when copying to userspace.

Cc: <stable@vger.kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Reported-by: Nicolas Waisman <nico@semmle.com>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20191004095132.15777-2-will@kernel.org
[adjust commit log a bit]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Will Deacon 2019-10-04 10:51:32 +01:00 committed by Johannes Berg
parent 4152561f5d
commit 4ac2813cc8
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
net/wireless/wext-sme.c
View File

@ -202,6 +202,7 @@ int cfg80211_mgd_wext_giwessid(struct net_device *dev,
struct iw_point *data, char *ssid)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
int ret = 0;
/* call only for station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
@ -219,7 +220,10 @@ int cfg80211_mgd_wext_giwessid(struct net_device *dev,
if (ie) {
data->flags = 1;
data->length = ie[1];
memcpy(ssid, ie + 2, data->length);
if (data->length > IW_ESSID_MAX_SIZE)
ret = -EINVAL;
else
memcpy(ssid, ie + 2, data->length);
}
rcu_read_unlock();
} else if (wdev->wext.connect.ssid && wdev->wext.connect.ssid_len) {
@ -229,7 +233,7 @@ int cfg80211_mgd_wext_giwessid(struct net_device *dev,
}
wdev_unlock(wdev);
return 0;
return ret;
}
int cfg80211_mgd_wext_siwap(struct net_device *dev,