From 0f7e90faddeef53a3568f449a0c3992d77510b66 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Tue, 23 Feb 2021 13:19:26 +0800 Subject: mac80211: Allow HE operation to be longer than expected. We observed some Cisco APs sending the following HE Operation IE in associate response: ff 0a 24 f4 3f 00 01 fc ff 00 00 00 Its HE operation parameter is 0x003ff4, so the expected total length is 7 which does not match the actual length = 10. This causes association failing with "HE AP is missing HE Capability/operation." According to P802.11ax_D4 Table9-94, HE operation is extensible, and according to 802.11-2016 10.27.8, STA should discard the part beyond the maximum length and parse the truncated element. Allow HE operation element to be longer than expected to handle this case and future extensions. Fixes: e4d005b80dee ("mac80211: refactor extended element parsing") Signed-off-by: Brian Norris Signed-off-by: Yen-lin Lai Link: https://lore.kernel.org/r/20210223051926.2653301-1-yenlinlai@chromium.org Signed-off-by: Johannes Berg --- net/mac80211/mlme.c | 2 +- net/mac80211/util.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 2e33a1263518..ce4e3855fec1 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -5071,7 +5071,7 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata, he_oper_ie = cfg80211_find_ext_ie(WLAN_EID_EXT_HE_OPERATION, ies->data, ies->len); if (he_oper_ie && - he_oper_ie[1] == ieee80211_he_oper_size(&he_oper_ie[3])) + he_oper_ie[1] >= ieee80211_he_oper_size(&he_oper_ie[3])) he_oper = (void *)(he_oper_ie + 3); else he_oper = NULL; diff --git a/net/mac80211/util.c b/net/mac80211/util.c index f080fcf60e45..c0fa526a45b4 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -968,7 +968,7 @@ 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); -- cgit v1.2.3