commit: 208c72f4fe44fe09577e7975ba0e7fa0278f3d03 From: Luciano Coelho <[email protected]> Date: Thu, 19 May 2011 00:43:38 +0300 Subject: [PATCH] nl80211: fix check for valid SSID size in scan operations
In both trigger_scan and sched_scan operations, we were checking for the SSID length before assigning the value correctly. Since the memory was just kzalloc'ed, the check was always failing and SSID with over 32 characters were allowed to go through. This was causing a buffer overflow when copying the actual SSID to the proper place. This bug has been there since 2.6.29-rc4. Cc: [email protected] Signed-off-by: Luciano Coelho <[email protected]> Signed-off-by: John W. Linville <[email protected]> --- net/wireless/nl80211.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index ec83f41..88a565f 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -3406,12 +3406,12 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info) i = 0; if (info->attrs[NL80211_ATTR_SCAN_SSIDS]) { nla_for_each_nested(attr, info->attrs[NL80211_ATTR_SCAN_SSIDS], tmp) { + request->ssids[i].ssid_len = nla_len(attr); if (request->ssids[i].ssid_len > IEEE80211_MAX_SSID_LEN) { err = -EINVAL; goto out_free; } memcpy(request->ssids[i].ssid, nla_data(attr), nla_len(attr)); - request->ssids[i].ssid_len = nla_len(attr); i++; } } @@ -3572,6 +3572,7 @@ static int nl80211_start_sched_scan(struct sk_buff *skb, if (info->attrs[NL80211_ATTR_SCAN_SSIDS]) { nla_for_each_nested(attr, info->attrs[NL80211_ATTR_SCAN_SSIDS], tmp) { + request->ssids[i].ssid_len = nla_len(attr); if (request->ssids[i].ssid_len > IEEE80211_MAX_SSID_LEN) { err = -EINVAL; @@ -3579,7 +3580,6 @@ static int nl80211_start_sched_scan(struct sk_buff *skb, } memcpy(request->ssids[i].ssid, nla_data(attr), nla_len(attr)); - request->ssids[i].ssid_len = nla_len(attr); i++; } } _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
