[21/23] mac80211: consider more elements in parsing CRC

Commit Message

Luca Coelho Jan. 31, 2020, 11:12 a.m. UTC

From: Johannes Berg <[e-mail]>

We only use the parsing CRC for checking if a beacon changed,
and elements with an ID > 63 cannot be represented in the
filter. Thus, like we did before with WMM and Cisco vendor
elements, just statically add these forgotten items to the
CRC:
 - WLAN_EID_VHT_OPERATION
 - WLAN_EID_OPMODE_NOTIF
 - WLAN_EID_EXT_HE_OPERATION.

I guess that in most cases when VHT/HE operation change, the HT
operation also changed, and so the change was picked up, but we
did notice that pure operating mode notification changes were
ignored.

Signed-off-by: Johannes Berg <[e-mail]>
Signed-off-by: Luca Coelho <[e-mail]>
---
 net/mac80211/util.c | 24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

Patch

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 7ddf0508779f..278d65ee8121 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -912,8 +912,12 @@  static void ieee80211_parse_extension_element(u32 *crc,
 		break;
 	case WLAN_EID_EXT_HE_OPERATION:
 		if (len >= sizeof(*elems->he_operation) &&
-		    len == ieee80211_he_oper_size(data) - 1)
+		    len == ieee80211_he_oper_size(data) - 1) {
+			if (crc)
+				*crc = crc32_be(*crc, (void *)elem,
+						elem->datalen + 2);
 			elems->he_operation = data;
+		}
 		break;
 	case WLAN_EID_EXT_UORA:
 		if (len == 1)
@@ -1108,16 +1112,22 @@  _ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
 				elem_parse_failed = true;
 			break;
 		case WLAN_EID_VHT_OPERATION:
-			if (elen >= sizeof(struct ieee80211_vht_operation))
+			if (elen >= sizeof(struct ieee80211_vht_operation)) {
 				elems->vht_operation = (void *)pos;
-			else
-				elem_parse_failed = true;
+				if (calc_crc)
+					crc = crc32_be(crc, pos - 2, elen + 2);
+				break;
+			}
+			elem_parse_failed = true;
 			break;
 		case WLAN_EID_OPMODE_NOTIF:
-			if (elen > 0)
+			if (elen > 0) {
 				elems->opmode_notif = pos;
-			else
-				elem_parse_failed = true;
+				if (calc_crc)
+					crc = crc32_be(crc, pos - 2, elen + 2);
+				break;
+			}
+			elem_parse_failed = true;
 			break;
 		case WLAN_EID_MESH_ID:
 			elems->mesh_id = pos;