From 60deb9f10eec5c6a20252ed36238b55d8b614a2c Mon Sep 17 00:00:00 2001 From: Siddh Raman Pant Date: Sat, 20 Aug 2022 01:33:40 +0530 Subject: [PATCH 1/6] wifi: mac80211: Fix UAF in ieee80211_scan_rx() ieee80211_scan_rx() tries to access scan_req->flags after a null check, but a UAF is observed when the scan is completed and __ieee80211_scan_completed() executes, which then calls cfg80211_scan_done() leading to the freeing of scan_req. Since scan_req is rcu_dereference()'d, prevent the racing in __ieee80211_scan_completed() by ensuring that from mac80211's POV it is no longer accessed from an RCU read critical section before we call cfg80211_scan_done(). Cc: stable@vger.kernel.org Link: https://syzkaller.appspot.com/bug?extid=f9acff9bf08a845f225d Reported-by: syzbot+f9acff9bf08a845f225d@syzkaller.appspotmail.com Suggested-by: Johannes Berg Signed-off-by: Siddh Raman Pant Link: https://lore.kernel.org/r/20220819200340.34826-1-code@siddh.me Signed-off-by: Johannes Berg --- net/mac80211/scan.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index fa8ddf576bc1c..c4f2aeb31da3a 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -469,16 +469,19 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) scan_req = rcu_dereference_protected(local->scan_req, lockdep_is_held(&local->mtx)); - if (scan_req != local->int_scan_req) { - local->scan_info.aborted = aborted; - cfg80211_scan_done(scan_req, &local->scan_info); - } RCU_INIT_POINTER(local->scan_req, NULL); RCU_INIT_POINTER(local->scan_sdata, NULL); local->scanning = 0; local->scan_chandef.chan = NULL; + synchronize_rcu(); + + if (scan_req != local->int_scan_req) { + local->scan_info.aborted = aborted; + cfg80211_scan_done(scan_req, &local->scan_info); + } + /* Set power back to normal operating levels. */ ieee80211_hw_config(local, 0); From 36fe8e4e5cb02131719612aea1e64379670d1846 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Tue, 23 Aug 2022 15:22:23 +0200 Subject: [PATCH 2/6] wifi: mac80211: always free sta in __sta_info_alloc in case of error Free sta pointer in __sta_info_alloc routine if sta_info_alloc_link() fails. Fixes: 246b39e4a1ba5 ("wifi: mac80211: refactor some sta_info link handling") Signed-off-by: Lorenzo Bianconi Link: https://lore.kernel.org/r/a3d079208684cddbc25289f7f7e0fed795b0cad4.1661260857.git.lorenzo@kernel.org Signed-off-by: Johannes Berg --- net/mac80211/sta_info.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index cb23da9aff1e6..330dab41f2fef 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -494,7 +494,7 @@ __sta_info_alloc(struct ieee80211_sub_if_data *sdata, sta->sdata = sdata; if (sta_info_alloc_link(local, &sta->deflink, gfp)) - return NULL; + goto free; if (link_id >= 0) { sta_info_add_link(sta, link_id, &sta->deflink, From 62b03f45c6352410d13bf0710d24ef6290632eb1 Mon Sep 17 00:00:00 2001 From: Yang Yingliang Date: Thu, 18 Aug 2022 12:33:49 +0800 Subject: [PATCH 3/6] wifi: mac80211: fix possible leak in ieee80211_tx_control_port() Add missing dev_kfree_skb() in an error path in ieee80211_tx_control_port() to avoid a memory leak. Fixes: dd820ed6336a ("wifi: mac80211: return error from control port TX for drops") Signed-off-by: Yang Yingliang Link: https://lore.kernel.org/r/20220818043349.4168835-1-yangyingliang@huawei.com Signed-off-by: Johannes Berg --- net/mac80211/tx.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 45df9932d0ba1..594bd70ee641a 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -5885,6 +5885,7 @@ int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev, rcu_read_lock(); err = ieee80211_lookup_ra_sta(sdata, skb, &sta); if (err) { + dev_kfree_skb(skb); rcu_read_unlock(); return err; } From 15bc8966b6d3a5b9bfe4c9facfa02f2b69b1e5f0 Mon Sep 17 00:00:00 2001 From: Siddh Raman Pant Date: Sun, 14 Aug 2022 20:45:12 +0530 Subject: [PATCH 4/6] wifi: mac80211: Don't finalize CSA in IBSS mode if state is disconnected When we are not connected to a channel, sending channel "switch" announcement doesn't make any sense. The BSS list is empty in that case. This causes the for loop in cfg80211_get_bss() to be bypassed, so the function returns NULL (check line 1424 of net/wireless/scan.c), causing the WARN_ON() in ieee80211_ibss_csa_beacon() to get triggered (check line 500 of net/mac80211/ibss.c), which was consequently reported on the syzkaller dashboard. Thus, check if we have an existing connection before generating the CSA beacon in ieee80211_ibss_finish_csa(). Cc: stable@vger.kernel.org Fixes: cd7760e62c2a ("mac80211: add support for CSA in IBSS mode") Link: https://syzkaller.appspot.com/bug?id=05603ef4ae8926761b678d2939a3b2ad28ab9ca6 Reported-by: syzbot+b6c9fe29aefe68e4ad34@syzkaller.appspotmail.com Signed-off-by: Siddh Raman Pant Tested-by: syzbot+b6c9fe29aefe68e4ad34@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20220814151512.9985-1-code@siddh.me Signed-off-by: Johannes Berg --- net/mac80211/ibss.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c index d56890e3fabb3..9b283bbc7bb4b 100644 --- a/net/mac80211/ibss.c +++ b/net/mac80211/ibss.c @@ -530,6 +530,10 @@ int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) sdata_assert_lock(sdata); + /* When not connected/joined, sending CSA doesn't make sense. */ + if (ifibss->state != IEEE80211_IBSS_MLME_JOINED) + return -ENOLINK; + /* update cfg80211 bss information with the new channel */ if (!is_zero_ether_addr(ifibss->bssid)) { cbss = cfg80211_get_bss(sdata->local->hw.wiphy, From d776763f48084926b5d9e25507a3ddb7c9243d5e Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 4 Aug 2022 10:03:21 +0300 Subject: [PATCH 5/6] wifi: cfg80211: debugfs: fix return type in ht40allow_map_read() The return type is supposed to be ssize_t, which is signed long, but "r" was declared as unsigned int. This means that on 64 bit systems we return positive values instead of negative error codes. Fixes: 80a3511d70e8 ("cfg80211: add debugfs HT40 allow map") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/YutvOQeJm0UjLhwU@kili Signed-off-by: Johannes Berg --- net/wireless/debugfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/wireless/debugfs.c b/net/wireless/debugfs.c index aab43469a2f04..0878b162890af 100644 --- a/net/wireless/debugfs.c +++ b/net/wireless/debugfs.c @@ -65,9 +65,10 @@ static ssize_t ht40allow_map_read(struct file *file, { struct wiphy *wiphy = file->private_data; char *buf; - unsigned int offset = 0, buf_size = PAGE_SIZE, i, r; + unsigned int offset = 0, buf_size = PAGE_SIZE, i; enum nl80211_band band; struct ieee80211_supported_band *sband; + ssize_t r; buf = kzalloc(buf_size, GFP_KERNEL); if (!buf) From 55f0a4894484e8d6ddf662f5aebbf3b4cb028541 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 28 Jul 2022 17:25:16 +0300 Subject: [PATCH 6/6] wifi: mac80211: potential NULL dereference in ieee80211_tx_control_port() The ieee80211_lookup_ra_sta() function will sometimes set "sta" to NULL so add this NULL check to prevent an Oops. Fixes: 9dd1953846c7 ("wifi: nl80211/mac80211: clarify link ID in control port TX") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/YuKcTAyO94YOy0Bu@kili Signed-off-by: Johannes Berg --- net/mac80211/tx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 594bd70ee641a..bf7fe6cd9dfca 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -5900,7 +5900,7 @@ int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev, * for MLO STA, the SA should be the AP MLD address, but * the link ID has been selected already */ - if (sta->sta.mlo) + if (sta && sta->sta.mlo) memcpy(ehdr->h_source, sdata->vif.addr, ETH_ALEN); } rcu_read_unlock();