From 79c92ca42b5a3e0ea172ea2ce8df8e125af237da Mon Sep 17 00:00:00 2001 From: Yu Wang Date: Fri, 10 May 2019 17:04:52 +0800 Subject: [PATCH] mac80211: handle deauthentication/disassociation from TDLS peer When receiving a deauthentication/disassociation frame from a TDLS peer, a station should not disconnect the current AP, but only disable the current TDLS link if it's enabled. Without this change, a TDLS issue can be reproduced by following the steps as below: 1. STA-1 and STA-2 are connected to AP, bidirection traffic is running between STA-1 and STA-2. 2. Set up TDLS link between STA-1 and STA-2, stay for a while, then teardown TDLS link. 3. Repeat step #2 and monitor the connection between STA and AP. During the test, one STA may send a deauthentication/disassociation frame to another, after TDLS teardown, with reason code 6/7, which means: Class 2/3 frame received from nonassociated STA. On receive this frame, the receiver STA will disconnect the current AP and then reconnect. It's not a expected behavior, purpose of this frame should be disabling the TDLS link, not the link with AP. Cc: stable@vger.kernel.org Signed-off-by: Yu Wang Signed-off-by: Johannes Berg --- net/mac80211/ieee80211_i.h | 3 +++ net/mac80211/mlme.c | 12 +++++++++++- net/mac80211/tdls.c | 23 +++++++++++++++++++++++ 3 files changed, 37 insertions(+), 1 deletion(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 073a8235ae1bd..a8af4aafa1171 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -2225,6 +2225,9 @@ void ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy, const u8 *addr); void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata); void ieee80211_tdls_chsw_work(struct work_struct *wk); +void ieee80211_tdls_handle_disconnect(struct ieee80211_sub_if_data *sdata, + const u8 *peer, u16 reason); +const char *ieee80211_get_reason_code_string(u16 reason_code); extern const struct ethtool_ops ieee80211_ethtool_ops; diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index b7a9fe3d5fcb7..383b0df100e4b 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -2963,7 +2963,7 @@ static void ieee80211_rx_mgmt_auth(struct ieee80211_sub_if_data *sdata, #define case_WLAN(type) \ case WLAN_REASON_##type: return #type -static const char *ieee80211_get_reason_code_string(u16 reason_code) +const char *ieee80211_get_reason_code_string(u16 reason_code) { switch (reason_code) { case_WLAN(UNSPECIFIED); @@ -3028,6 +3028,11 @@ static void ieee80211_rx_mgmt_deauth(struct ieee80211_sub_if_data *sdata, if (len < 24 + 2) return; + if (!ether_addr_equal(mgmt->bssid, mgmt->sa)) { + ieee80211_tdls_handle_disconnect(sdata, mgmt->sa, reason_code); + return; + } + if (ifmgd->associated && ether_addr_equal(mgmt->bssid, ifmgd->associated->bssid)) { const u8 *bssid = ifmgd->associated->bssid; @@ -3077,6 +3082,11 @@ static void ieee80211_rx_mgmt_disassoc(struct ieee80211_sub_if_data *sdata, reason_code = le16_to_cpu(mgmt->u.disassoc.reason_code); + if (!ether_addr_equal(mgmt->bssid, mgmt->sa)) { + ieee80211_tdls_handle_disconnect(sdata, mgmt->sa, reason_code); + return; + } + sdata_info(sdata, "disassociated from %pM (Reason: %u=%s)\n", mgmt->sa, reason_code, ieee80211_get_reason_code_string(reason_code)); diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c index 24c37f91ca461..ba8fe48952d9d 100644 --- a/net/mac80211/tdls.c +++ b/net/mac80211/tdls.c @@ -1994,3 +1994,26 @@ void ieee80211_tdls_chsw_work(struct work_struct *wk) } rtnl_unlock(); } + +void ieee80211_tdls_handle_disconnect(struct ieee80211_sub_if_data *sdata, + const u8 *peer, u16 reason) +{ + struct ieee80211_sta *sta; + + rcu_read_lock(); + sta = ieee80211_find_sta(&sdata->vif, peer); + if (!sta || !sta->tdls) { + rcu_read_unlock(); + return; + } + rcu_read_unlock(); + + tdls_dbg(sdata, "disconnected from TDLS peer %pM (Reason: %u=%s)\n", + peer, reason, + ieee80211_get_reason_code_string(reason)); + + ieee80211_tdls_oper_request(&sdata->vif, peer, + NL80211_TDLS_TEARDOWN, + WLAN_REASON_TDLS_TEARDOWN_UNREACHABLE, + GFP_ATOMIC); +}