--- /dev/null
+From: Felix Fietkau <nbd@nbd.name>
+Date: Tue, 13 Dec 2022 21:03:19 +0100
+Subject: [PATCH] wifi: mac80211: fix initialization of rx->link and
+ rx->link_sta
+
+There are some codepaths that do not initialize rx->link_sta properly. This
+causes a crash in places which assume that rx->link_sta is valid if rx->sta
+is valid.
+One known instance is triggered by __ieee80211_rx_h_amsdu being called from
+fast-rx.
+
+Since the initialization of rx->link and rx->link_sta is rather convoluted
+and duplicated in many places, clean it up by using a helper function to
+set it.
+
+Fixes: ccdde7c74ffd ("wifi: mac80211: properly implement MLO key handling")
+Fixes: b320d6c456ff ("wifi: mac80211: use correct rx link_sta instead of default")
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/rx.c
++++ b/net/mac80211/rx.c
+@@ -4067,6 +4067,55 @@ static void ieee80211_invoke_rx_handlers
+ #undef CALL_RXH
+ }
+
++static bool
++ieee80211_rx_is_valid_sta_link_id(struct ieee80211_sta *sta, u8 link_id)
++{
++ if (!sta->mlo)
++ return false;
++
++ return !!(sta->valid_links & BIT(link_id));
++}
++
++static bool ieee80211_rx_data_set_link(struct ieee80211_rx_data *rx,
++ u8 link_id)
++{
++ if (!ieee80211_rx_is_valid_sta_link_id(&rx->sta->sta, link_id))
++ return false;
++
++ rx->link_id = link_id;
++ rx->link = rcu_dereference(rx->sdata->link[link_id]);
++ rx->link_sta = rcu_dereference(rx->sta->link[link_id]);
++
++ return rx->link && rx->link_sta;
++}
++
++static bool ieee80211_rx_data_set_sta(struct ieee80211_rx_data *rx,
++ struct ieee80211_sta *pubsta,
++ int link_id)
++{
++ struct sta_info *sta;
++
++ sta = container_of(pubsta, struct sta_info, sta);
++
++ rx->link_id = link_id;
++ rx->sta = sta;
++
++ if (sta) {
++ rx->local = sta->sdata->local;
++ rx->sdata = sta->sdata;
++ rx->link_sta = &sta->deflink;
++
++ if (link_id >= 0 &&
++ !ieee80211_rx_data_set_link(rx, link_id))
++ return false;
++ }
++
++ if (link_id < 0)
++ rx->link = &rx->sdata->deflink;
++
++ return true;
++}
++
+ /*
+ * This function makes calls into the RX path, therefore
+ * it has to be invoked under RCU read lock.
+@@ -4075,16 +4124,19 @@ void ieee80211_release_reorder_timeout(s
+ {
+ struct sk_buff_head frames;
+ struct ieee80211_rx_data rx = {
+- .sta = sta,
+- .sdata = sta->sdata,
+- .local = sta->local,
+ /* This is OK -- must be QoS data frame */
+ .security_idx = tid,
+ .seqno_idx = tid,
+- .link_id = -1,
+ };
+ struct tid_ampdu_rx *tid_agg_rx;
+- u8 link_id;
++ int link_id = -1;
++
++ /* FIXME: statistics won't be right with this */
++ if (sta->sta.valid_links)
++ link_id = ffs(sta->sta.valid_links) - 1;
++
++ if (!ieee80211_rx_data_set_sta(&rx, &sta->sta, link_id))
++ return;
+
+ tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
+ if (!tid_agg_rx)
+@@ -4104,10 +4156,6 @@ void ieee80211_release_reorder_timeout(s
+ };
+ drv_event_callback(rx.local, rx.sdata, &event);
+ }
+- /* FIXME: statistics won't be right with this */
+- link_id = sta->sta.valid_links ? ffs(sta->sta.valid_links) - 1 : 0;
+- rx.link = rcu_dereference(sta->sdata->link[link_id]);
+- rx.link_sta = rcu_dereference(sta->link[link_id]);
+
+ ieee80211_rx_handlers(&rx, &frames);
+ }
+@@ -4123,7 +4171,6 @@ void ieee80211_mark_rx_ba_filtered_frame
+ /* This is OK -- must be QoS data frame */
+ .security_idx = tid,
+ .seqno_idx = tid,
+- .link_id = -1,
+ };
+ int i, diff;
+
+@@ -4134,10 +4181,8 @@ void ieee80211_mark_rx_ba_filtered_frame
+
+ sta = container_of(pubsta, struct sta_info, sta);
+
+- rx.sta = sta;
+- rx.sdata = sta->sdata;
+- rx.link = &rx.sdata->deflink;
+- rx.local = sta->local;
++ if (!ieee80211_rx_data_set_sta(&rx, pubsta, -1))
++ return;
+
+ rcu_read_lock();
+ tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
+@@ -4524,15 +4569,6 @@ void ieee80211_check_fast_rx_iface(struc
+ mutex_unlock(&local->sta_mtx);
+ }
+
+-static bool
+-ieee80211_rx_is_valid_sta_link_id(struct ieee80211_sta *sta, u8 link_id)
+-{
+- if (!sta->mlo)
+- return false;
+-
+- return !!(sta->valid_links & BIT(link_id));
+-}
+-
+ static void ieee80211_rx_8023(struct ieee80211_rx_data *rx,
+ struct ieee80211_fast_rx *fast_rx,
+ int orig_len)
+@@ -4643,7 +4679,6 @@ static bool ieee80211_invoke_fast_rx(str
+ struct sk_buff *skb = rx->skb;
+ struct ieee80211_hdr *hdr = (void *)skb->data;
+ struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+- struct sta_info *sta = rx->sta;
+ int orig_len = skb->len;
+ int hdrlen = ieee80211_hdrlen(hdr->frame_control);
+ int snap_offs = hdrlen;
+@@ -4655,7 +4690,6 @@ static bool ieee80211_invoke_fast_rx(str
+ u8 da[ETH_ALEN];
+ u8 sa[ETH_ALEN];
+ } addrs __aligned(2);
+- struct link_sta_info *link_sta;
+ struct ieee80211_sta_rx_stats *stats;
+
+ /* for parallel-rx, we need to have DUP_VALIDATED, otherwise we write
+@@ -4758,18 +4792,10 @@ static bool ieee80211_invoke_fast_rx(str
+ drop:
+ dev_kfree_skb(skb);
+
+- if (rx->link_id >= 0) {
+- link_sta = rcu_dereference(sta->link[rx->link_id]);
+- if (!link_sta)
+- return true;
+- } else {
+- link_sta = &sta->deflink;
+- }
+-
+ if (fast_rx->uses_rss)
+- stats = this_cpu_ptr(link_sta->pcpu_rx_stats);
++ stats = this_cpu_ptr(rx->link_sta->pcpu_rx_stats);
+ else
+- stats = &link_sta->rx_stats;
++ stats = &rx->link_sta->rx_stats;
+
+ stats->dropped++;
+ return true;
+@@ -4787,7 +4813,6 @@ static bool ieee80211_prepare_and_rx_han
+ struct ieee80211_local *local = rx->local;
+ struct ieee80211_sub_if_data *sdata = rx->sdata;
+ struct ieee80211_hdr *hdr = (void *)skb->data;
+- struct link_sta_info *link_sta = NULL;
+ struct ieee80211_link_data *link;
+
+ rx->skb = skb;
+@@ -4810,35 +4835,6 @@ static bool ieee80211_prepare_and_rx_han
+ if (!ieee80211_accept_frame(rx))
+ return false;
+
+- if (rx->link_id >= 0) {
+- link = rcu_dereference(rx->sdata->link[rx->link_id]);
+-
+- /* we might race link removal */
+- if (!link)
+- return true;
+- rx->link = link;
+-
+- if (rx->sta) {
+- rx->link_sta =
+- rcu_dereference(rx->sta->link[rx->link_id]);
+- if (!rx->link_sta)
+- return true;
+- }
+- } else {
+- if (rx->sta)
+- rx->link_sta = &rx->sta->deflink;
+-
+- rx->link = &sdata->deflink;
+- }
+-
+- if (unlikely(!is_multicast_ether_addr(hdr->addr1) &&
+- rx->link_id >= 0 && rx->sta && rx->sta->sta.mlo)) {
+- link_sta = rcu_dereference(rx->sta->link[rx->link_id]);
+-
+- if (WARN_ON_ONCE(!link_sta))
+- return true;
+- }
+-
+ if (!consume) {
+ struct skb_shared_hwtstamps *shwt;
+
+@@ -4858,16 +4854,16 @@ static bool ieee80211_prepare_and_rx_han
+ shwt->hwtstamp = skb_hwtstamps(skb)->hwtstamp;
+ }
+
+- if (unlikely(link_sta)) {
++ if (unlikely(rx->sta && rx->sta->sta.mlo)) {
+ /* translate to MLD addresses */
+ if (ether_addr_equal(link->conf->addr, hdr->addr1))
+ ether_addr_copy(hdr->addr1, rx->sdata->vif.addr);
+- if (ether_addr_equal(link_sta->addr, hdr->addr2))
++ if (ether_addr_equal(rx->link_sta->addr, hdr->addr2))
+ ether_addr_copy(hdr->addr2, rx->sta->addr);
+ /* translate A3 only if it's the BSSID */
+ if (!ieee80211_has_tods(hdr->frame_control) &&
+ !ieee80211_has_fromds(hdr->frame_control)) {
+- if (ether_addr_equal(link_sta->addr, hdr->addr3))
++ if (ether_addr_equal(rx->link_sta->addr, hdr->addr3))
+ ether_addr_copy(hdr->addr3, rx->sta->addr);
+ else if (ether_addr_equal(link->conf->addr, hdr->addr3))
+ ether_addr_copy(hdr->addr3, rx->sdata->vif.addr);
+@@ -4888,6 +4884,7 @@ static void __ieee80211_rx_handle_8023(s
+ struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+ struct ieee80211_fast_rx *fast_rx;
+ struct ieee80211_rx_data rx;
++ int link_id = -1;
+
+ memset(&rx, 0, sizeof(rx));
+ rx.skb = skb;
+@@ -4904,12 +4901,8 @@ static void __ieee80211_rx_handle_8023(s
+ if (!pubsta)
+ goto drop;
+
+- rx.sta = container_of(pubsta, struct sta_info, sta);
+- rx.sdata = rx.sta->sdata;
+-
+- if (status->link_valid &&
+- !ieee80211_rx_is_valid_sta_link_id(pubsta, status->link_id))
+- goto drop;
++ if (status->link_valid)
++ link_id = status->link_id;
+
+ /*
+ * TODO: Should the frame be dropped if the right link_id is not
+@@ -4918,19 +4911,8 @@ static void __ieee80211_rx_handle_8023(s
+ * link_id is used only for stats purpose and updating the stats on
+ * the deflink is fine?
+ */
+- if (status->link_valid)
+- rx.link_id = status->link_id;
+-
+- if (rx.link_id >= 0) {
+- struct ieee80211_link_data *link;
+-
+- link = rcu_dereference(rx.sdata->link[rx.link_id]);
+- if (!link)
+- goto drop;
+- rx.link = link;
+- } else {
+- rx.link = &rx.sdata->deflink;
+- }
++ if (!ieee80211_rx_data_set_sta(&rx, pubsta, link_id))
++ goto drop;
+
+ fast_rx = rcu_dereference(rx.sta->fast_rx);
+ if (!fast_rx)
+@@ -4948,6 +4930,8 @@ static bool ieee80211_rx_for_interface(s
+ {
+ struct link_sta_info *link_sta;
+ struct ieee80211_hdr *hdr = (void *)skb->data;
++ struct sta_info *sta;
++ int link_id = -1;
+
+ /*
+ * Look up link station first, in case there's a
+@@ -4957,24 +4941,19 @@ static bool ieee80211_rx_for_interface(s
+ */
+ link_sta = link_sta_info_get_bss(rx->sdata, hdr->addr2);
+ if (link_sta) {
+- rx->sta = link_sta->sta;
+- rx->link_id = link_sta->link_id;
++ sta = link_sta->sta;
++ link_id = link_sta->link_id;
+ } else {
+ struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+
+- rx->sta = sta_info_get_bss(rx->sdata, hdr->addr2);
+- if (rx->sta) {
+- if (status->link_valid &&
+- !ieee80211_rx_is_valid_sta_link_id(&rx->sta->sta,
+- status->link_id))
+- return false;
+-
+- rx->link_id = status->link_valid ? status->link_id : -1;
+- } else {
+- rx->link_id = -1;
+- }
++ sta = sta_info_get_bss(rx->sdata, hdr->addr2);
++ if (status->link_valid)
++ link_id = status->link_id;
+ }
+
++ if (!ieee80211_rx_data_set_sta(rx, &sta->sta, link_id))
++ return false;
++
+ return ieee80211_prepare_and_rx_handle(rx, skb, consume);
+ }
+
+@@ -5033,19 +5012,15 @@ static void __ieee80211_rx_handle_packet
+
+ if (ieee80211_is_data(fc)) {
+ struct sta_info *sta, *prev_sta;
+- u8 link_id = status->link_id;
++ int link_id = -1;
+
+- if (pubsta) {
+- rx.sta = container_of(pubsta, struct sta_info, sta);
+- rx.sdata = rx.sta->sdata;
++ if (status->link_valid)
++ link_id = status->link_id;
+
+- if (status->link_valid &&
+- !ieee80211_rx_is_valid_sta_link_id(pubsta, link_id))
++ if (pubsta) {
++ if (!ieee80211_rx_data_set_sta(&rx, pubsta, link_id))
+ goto out;
+
+- if (status->link_valid)
+- rx.link_id = status->link_id;
+-
+ /*
+ * In MLO connection, fetch the link_id using addr2
+ * when the driver does not pass link_id in status.
+@@ -5063,7 +5038,7 @@ static void __ieee80211_rx_handle_packet
+ if (!link_sta)
+ goto out;
+
+- rx.link_id = link_sta->link_id;
++ ieee80211_rx_data_set_link(&rx, link_sta->link_id);
+ }
+
+ if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
+@@ -5079,30 +5054,25 @@ static void __ieee80211_rx_handle_packet
+ continue;
+ }
+
+- if ((status->link_valid &&
+- !ieee80211_rx_is_valid_sta_link_id(&prev_sta->sta,
+- link_id)) ||
+- (!status->link_valid && prev_sta->sta.mlo))
++ if (!ieee80211_rx_data_set_sta(&rx, &prev_sta->sta,
++ link_id))
++ goto out;
++
++ if (!status->link_valid && prev_sta->sta.mlo)
+ continue;
+
+- rx.link_id = status->link_valid ? link_id : -1;
+- rx.sta = prev_sta;
+- rx.sdata = prev_sta->sdata;
+ ieee80211_prepare_and_rx_handle(&rx, skb, false);
+
+ prev_sta = sta;
+ }
+
+ if (prev_sta) {
+- if ((status->link_valid &&
+- !ieee80211_rx_is_valid_sta_link_id(&prev_sta->sta,
+- link_id)) ||
+- (!status->link_valid && prev_sta->sta.mlo))
++ if (!ieee80211_rx_data_set_sta(&rx, &prev_sta->sta,
++ link_id))
+ goto out;
+
+- rx.link_id = status->link_valid ? link_id : -1;
+- rx.sta = prev_sta;
+- rx.sdata = prev_sta->sdata;
++ if (!status->link_valid && prev_sta->sta.mlo)
++ goto out;
+
+ if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
+ return;
projects / openwrt / staging / dedeckeh.git / commitdiff