diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index cf79656ce09c..2b54fdd8ca15 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -2910,6 +2910,8 @@ struct cfg80211_bss_ies { * own the beacon_ies, but they're just pointers to the ones from the * @hidden_beacon_bss struct) * @proberesp_ies: the information elements from the last Probe Response frame + * @proberesp_ecsa_stuck: ECSA element is stuck in the Probe Response frame, + * cannot rely on it having valid data * @hidden_beacon_bss: in case this BSS struct represents a probe response from * a BSS that hides the SSID in its beacon, this points to the BSS struct * that holds the beacon data. @beacon_ies is still valid, of course, and @@ -2950,6 +2952,8 @@ struct cfg80211_bss { u8 chains; s8 chain_signal[IEEE80211_MAX_CHAINS]; + u8 proberesp_ecsa_stuck:1; + u8 bssid_index; u8 max_bssid_indicator; diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 2249b1a89d1c..389a52c29bfc 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -1731,6 +1731,61 @@ static void cfg80211_update_hidden_bsses(struct cfg80211_internal_bss *known, } } +static void cfg80211_check_stuck_ecsa(struct cfg80211_registered_device *rdev, + struct cfg80211_internal_bss *known, + const struct cfg80211_bss_ies *old) +{ + const struct ieee80211_ext_chansw_ie *ecsa; + const struct element *elem_new, *elem_old; + const struct cfg80211_bss_ies *new, *bcn; + + if (known->pub.proberesp_ecsa_stuck) + return; + + new = rcu_dereference_protected(known->pub.proberesp_ies, + lockdep_is_held(&rdev->bss_lock)); + if (WARN_ON(!new)) + return; + + if (new->tsf - old->tsf < USEC_PER_SEC) + return; + + elem_old = cfg80211_find_elem(WLAN_EID_EXT_CHANSWITCH_ANN, + old->data, old->len); + if (!elem_old) + return; + + elem_new = cfg80211_find_elem(WLAN_EID_EXT_CHANSWITCH_ANN, + new->data, new->len); + if (!elem_new) + return; + + bcn = rcu_dereference_protected(known->pub.beacon_ies, + lockdep_is_held(&rdev->bss_lock)); + if (bcn && + cfg80211_find_elem(WLAN_EID_EXT_CHANSWITCH_ANN, + bcn->data, bcn->len)) + return; + + if (elem_new->datalen != elem_old->datalen) + return; + if (elem_new->datalen < sizeof(struct ieee80211_ext_chansw_ie)) + return; + if (memcmp(elem_new->data, elem_old->data, elem_new->datalen)) + return; + + ecsa = (void *)elem_new->data; + + if (!ecsa->mode) + return; + + if (ecsa->new_ch_num != + ieee80211_frequency_to_channel(known->pub.channel->center_freq)) + return; + + known->pub.proberesp_ecsa_stuck = 1; +} + static bool cfg80211_update_known_bss(struct cfg80211_registered_device *rdev, struct cfg80211_internal_bss *known, @@ -1750,8 +1805,10 @@ cfg80211_update_known_bss(struct cfg80211_registered_device *rdev, /* Override possible earlier Beacon frame IEs */ rcu_assign_pointer(known->pub.ies, new->pub.proberesp_ies); - if (old) + if (old) { + cfg80211_check_stuck_ecsa(rdev, known, old); kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); + } } if (rcu_access_pointer(new->pub.beacon_ies)) {