This is a note to let you know that I've just added the patch titled cfg80211/mac80211: fix BSS leaks when abandoning assoc attempts to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: cfg80211-mac80211-fix-bss-leaks-when-abandoning-assoc-attempts.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From e6f462df9acd2a3295e5d34eb29e2823220cf129 Mon Sep 17 00:00:00 2001 From: Johannes Berg <johannes.berg@xxxxxxxxx> Date: Thu, 8 Dec 2016 17:22:09 +0100 Subject: cfg80211/mac80211: fix BSS leaks when abandoning assoc attempts From: Johannes Berg <johannes.berg@xxxxxxxxx> commit e6f462df9acd2a3295e5d34eb29e2823220cf129 upstream. When mac80211 abandons an association attempt, it may free all the data structures, but inform cfg80211 and userspace about it only by sending the deauth frame it received, in which case cfg80211 has no link to the BSS struct that was used and will not cfg80211_unhold_bss() it. Fix this by providing a way to inform cfg80211 of this with the BSS entry passed, so that it can clean up properly, and use this ability in the appropriate places in mac80211. This isn't ideal: some code is more or less duplicated and tracing is missing. However, it's a fairly small change and it's thus easier to backport - cleanups can come later. Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/net/cfg80211.h | 11 +++++++++++ net/mac80211/mlme.c | 21 ++++++++++++--------- net/wireless/core.h | 1 + net/wireless/mlme.c | 12 ++++++++++++ net/wireless/sme.c | 14 ++++++++++++++ 5 files changed, 50 insertions(+), 9 deletions(-) --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -4258,6 +4258,17 @@ void cfg80211_rx_assoc_resp(struct net_d void cfg80211_assoc_timeout(struct net_device *dev, struct cfg80211_bss *bss); /** + * cfg80211_abandon_assoc - notify cfg80211 of abandoned association attempt + * @dev: network device + * @bss: The BSS entry with which association was abandoned. + * + * Call this whenever - for reasons reported through other API, like deauth RX, + * an association attempt was abandoned. + * This function may sleep. The caller must hold the corresponding wdev's mutex. + */ +void cfg80211_abandon_assoc(struct net_device *dev, struct cfg80211_bss *bss); + +/** * cfg80211_tx_mlme_mgmt - notification of transmitted deauth/disassoc frame * @dev: network device * @buf: 802.11 frame (header + body) --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -2517,7 +2517,7 @@ static void ieee80211_destroy_auth_data( } static void ieee80211_destroy_assoc_data(struct ieee80211_sub_if_data *sdata, - bool assoc) + bool assoc, bool abandon) { struct ieee80211_mgd_assoc_data *assoc_data = sdata->u.mgd.assoc_data; @@ -2539,6 +2539,9 @@ static void ieee80211_destroy_assoc_data mutex_lock(&sdata->local->mtx); ieee80211_vif_release_channel(sdata); mutex_unlock(&sdata->local->mtx); + + if (abandon) + cfg80211_abandon_assoc(sdata->dev, assoc_data->bss); } kfree(assoc_data); @@ -2768,7 +2771,7 @@ static void ieee80211_rx_mgmt_deauth(str bssid, reason_code, ieee80211_get_reason_code_string(reason_code)); - ieee80211_destroy_assoc_data(sdata, false); + ieee80211_destroy_assoc_data(sdata, false, true); cfg80211_rx_mlme_mgmt(sdata->dev, (u8 *)mgmt, len); return; @@ -3173,14 +3176,14 @@ static void ieee80211_rx_mgmt_assoc_resp if (status_code != WLAN_STATUS_SUCCESS) { sdata_info(sdata, "%pM denied association (code=%d)\n", mgmt->sa, status_code); - ieee80211_destroy_assoc_data(sdata, false); + ieee80211_destroy_assoc_data(sdata, false, false); event.u.mlme.status = MLME_DENIED; event.u.mlme.reason = status_code; drv_event_callback(sdata->local, sdata, &event); } else { if (!ieee80211_assoc_success(sdata, bss, mgmt, len)) { /* oops -- internal error -- send timeout for now */ - ieee80211_destroy_assoc_data(sdata, false); + ieee80211_destroy_assoc_data(sdata, false, false); cfg80211_assoc_timeout(sdata->dev, bss); return; } @@ -3193,7 +3196,7 @@ static void ieee80211_rx_mgmt_assoc_resp * recalc after assoc_data is NULL but before associated * is set can cause the interface to go idle */ - ieee80211_destroy_assoc_data(sdata, true); + ieee80211_destroy_assoc_data(sdata, true, false); /* get uapsd queues configuration */ uapsd_queues = 0; @@ -3888,7 +3891,7 @@ void ieee80211_sta_work(struct ieee80211 .u.mlme.status = MLME_TIMEOUT, }; - ieee80211_destroy_assoc_data(sdata, false); + ieee80211_destroy_assoc_data(sdata, false, false); cfg80211_assoc_timeout(sdata->dev, bss); drv_event_callback(sdata->local, sdata, &event); } @@ -4029,7 +4032,7 @@ void ieee80211_mgd_quiesce(struct ieee80 WLAN_REASON_DEAUTH_LEAVING, false, frame_buf); if (ifmgd->assoc_data) - ieee80211_destroy_assoc_data(sdata, false); + ieee80211_destroy_assoc_data(sdata, false, true); if (ifmgd->auth_data) ieee80211_destroy_auth_data(sdata, false); cfg80211_tx_mlme_mgmt(sdata->dev, frame_buf, @@ -4905,7 +4908,7 @@ int ieee80211_mgd_deauth(struct ieee8021 IEEE80211_STYPE_DEAUTH, req->reason_code, tx, frame_buf); - ieee80211_destroy_assoc_data(sdata, false); + ieee80211_destroy_assoc_data(sdata, false, true); ieee80211_report_disconnect(sdata, frame_buf, sizeof(frame_buf), true, req->reason_code); @@ -4980,7 +4983,7 @@ void ieee80211_mgd_stop(struct ieee80211 sdata_lock(sdata); if (ifmgd->assoc_data) { struct cfg80211_bss *bss = ifmgd->assoc_data->bss; - ieee80211_destroy_assoc_data(sdata, false); + ieee80211_destroy_assoc_data(sdata, false, false); cfg80211_assoc_timeout(sdata->dev, bss); } if (ifmgd->auth_data) --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -398,6 +398,7 @@ void cfg80211_sme_disassoc(struct wirele void cfg80211_sme_deauth(struct wireless_dev *wdev); void cfg80211_sme_auth_timeout(struct wireless_dev *wdev); void cfg80211_sme_assoc_timeout(struct wireless_dev *wdev); +void cfg80211_sme_abandon_assoc(struct wireless_dev *wdev); /* internal helpers */ bool cfg80211_supported_cipher_suite(struct wiphy *wiphy, u32 cipher); --- a/net/wireless/mlme.c +++ b/net/wireless/mlme.c @@ -149,6 +149,18 @@ void cfg80211_assoc_timeout(struct net_d } EXPORT_SYMBOL(cfg80211_assoc_timeout); +void cfg80211_abandon_assoc(struct net_device *dev, struct cfg80211_bss *bss) +{ + struct wireless_dev *wdev = dev->ieee80211_ptr; + struct wiphy *wiphy = wdev->wiphy; + + cfg80211_sme_abandon_assoc(wdev); + + cfg80211_unhold_bss(bss_from_pub(bss)); + cfg80211_put_bss(wiphy, bss); +} +EXPORT_SYMBOL(cfg80211_abandon_assoc); + void cfg80211_tx_mlme_mgmt(struct net_device *dev, const u8 *buf, size_t len) { struct wireless_dev *wdev = dev->ieee80211_ptr; --- a/net/wireless/sme.c +++ b/net/wireless/sme.c @@ -39,6 +39,7 @@ struct cfg80211_conn { CFG80211_CONN_ASSOCIATING, CFG80211_CONN_ASSOC_FAILED, CFG80211_CONN_DEAUTH, + CFG80211_CONN_ABANDON, CFG80211_CONN_CONNECTED, } state; u8 bssid[ETH_ALEN], prev_bssid[ETH_ALEN]; @@ -204,6 +205,8 @@ static int cfg80211_conn_do_work(struct cfg80211_mlme_deauth(rdev, wdev->netdev, params->bssid, NULL, 0, WLAN_REASON_DEAUTH_LEAVING, false); + /* fall through */ + case CFG80211_CONN_ABANDON: /* free directly, disconnected event already sent */ cfg80211_sme_free(wdev); return 0; @@ -423,6 +426,17 @@ void cfg80211_sme_assoc_timeout(struct w schedule_work(&rdev->conn_work); } +void cfg80211_sme_abandon_assoc(struct wireless_dev *wdev) +{ + struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy); + + if (!wdev->conn) + return; + + wdev->conn->state = CFG80211_CONN_ABANDON; + schedule_work(&rdev->conn_work); +} + static int cfg80211_sme_get_conn_ies(struct wireless_dev *wdev, const u8 *ies, size_t ies_len, const u8 **out_ies, size_t *out_ies_len) Patches currently in stable-queue which might be from johannes.berg@xxxxxxxxx are queue-4.4/cfg80211-mac80211-fix-bss-leaks-when-abandoning-assoc-attempts.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html