Merge tag 'wireless-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless

Johannes Berg says:

====================
More wireless fixes for 6.1

This has only the fixes for the scan parsing issues.

* tag 'wireless-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless:
  wifi: cfg80211: update hidden BSSes to avoid WARN_ON
  wifi: mac80211: fix crash in beacon protection for P2P-device
  wifi: mac80211_hwsim: avoid mac80211 warning on bad rate
  wifi: cfg80211: avoid nontransmitted BSS list corruption
  wifi: cfg80211: fix BSS refcounting bugs
  wifi: cfg80211: ensure length byte is present before access
  wifi: mac80211: fix MBSSID parsing use-after-free
  wifi: cfg80211/mac80211: reject bad MBSSID elements
  wifi: cfg80211: fix u8 overflow in cfg80211_update_notlisted_nontrans()
====================

Link: https://lore.kernel.org/r/20221013100522.46346-1-johannes@sipsolutions.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

1 files changed, 17 insertions, 15 deletions

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 1e929b82deef..b512cb37aafb 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1445,6 +1445,8 @@ static size_t ieee802_11_find_bssid_profile(const u8 *start, size_t len,
 	for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, start, len) {
 		if (elem->datalen < 2)
 			continue;
+		if (elem->data[0] < 1 || elem->data[0] > 8)
+			continue;
 
 		for_each_element(sub, elem->data + 1, elem->datalen - 1) {
 			u8 new_bssid[ETH_ALEN];
@@ -1504,24 +1506,26 @@ ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params)
 	const struct element *non_inherit = NULL;
 	u8 *nontransmitted_profile;
 	int nontransmitted_profile_len = 0;
+	size_t scratch_len = params->len;
 
-	elems = kzalloc(sizeof(*elems), GFP_ATOMIC);
+	elems = kzalloc(sizeof(*elems) + scratch_len, GFP_ATOMIC);
 	if (!elems)
 		return NULL;
 	elems->ie_start = params->start;
 	elems->total_len = params->len;
-
-	nontransmitted_profile = kmalloc(params->len, GFP_ATOMIC);
-	if (nontransmitted_profile) {
-		nontransmitted_profile_len =
-			ieee802_11_find_bssid_profile(params->start, params->len,
-						      elems, params->bss,
-						      nontransmitted_profile);
-		non_inherit =
-			cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
-					       nontransmitted_profile,
-					       nontransmitted_profile_len);
-	}
+	elems->scratch_len = scratch_len;
+	elems->scratch_pos = elems->scratch;
+
+	nontransmitted_profile = elems->scratch_pos;
+	nontransmitted_profile_len =
+		ieee802_11_find_bssid_profile(params->start, params->len,
+					      elems, params->bss,
+					      nontransmitted_profile);
+	elems->scratch_pos += nontransmitted_profile_len;
+	elems->scratch_len -= nontransmitted_profile_len;
+	non_inherit = cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
+					     nontransmitted_profile,
+					     nontransmitted_profile_len);
 
 	elems->crc = _ieee802_11_parse_elems_full(params, elems, non_inherit);
 
@@ -1555,8 +1559,6 @@ ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params)
 	    offsetofend(struct ieee80211_bssid_index, dtim_count))
 		elems->dtim_count = elems->bssid_index->dtim_count;
 
-	kfree(nontransmitted_profile);
-
 	return elems;
 }