mac80211: work around broken APs not including HT info

There are some APs, notably 2G/3G/4G Wifi routers, specifically the
"Onda PN51T", "Vodafone PocketWiFi 2", "ZTE MF60" and a similar
T-Mobile branded device [1] that erroneously don't include all the
needed information in (re)association response frames. Work around
this by assuming the information is the same as it was in the
beacon or probe response and using the data from there instead.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=58881.

[1] https://bbs.archlinux.org/viewtopic.php?pid=1277305

Note that this requires marking the first ieee802_11_parse_elems()
argument const, otherwise we'd get a compiler warning.

Cc: stable@vger.kernel.org
Reported-and-tested-by: Michal Zajac <manwe@manwe.pl>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 27e0715..72e6292 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -661,12 +661,12 @@ void ieee80211_queue_delayed_work(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_queue_delayed_work);
 
-u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, bool action,
+u32 ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
 			       struct ieee802_11_elems *elems,
 			       u64 filter, u32 crc)
 {
 	size_t left = len;
-	u8 *pos = start;
+	const u8 *pos = start;
 	bool calc_crc = filter != 0;
 	DECLARE_BITMAP(seen_elems, 256);
 	const u8 *ie;