Since mt7925_mac_sta_add publishes wcid, add publish check in mt76_sta_add to avoid reinitializing the wcid->poll_list. Found dev->sta_poll_list corruption when using mt7925 and 7.1-rc4. According to the corruption information, prev->next was changed to itself. wlan0: disconnect from AP 90:fb:5d:94:8b:e3 for new auth to 90:fb:5d:94:8b:e2 wlan0: authenticate with 90:fb:5d:94:8b:e2 (local address=84:9e:56:9c:7e:6b) wlan0: send auth to 90:fb:5d:94:8b:e2 (try 1/3) slab kmalloc-8k start ffff8c80958a6000 pointer offset 4160 size 8192 list_add corruption. prev->next should be next (ffff8c808a7488f8), but was ffff8c80958a7040. (prev=ffff8c80958a7040). mt76_wcid_add_poll+0x95/0xd0 [mt76] mt7925_mac_add_txs.part.0+0xa5/0xe0 [mt7925_common] mt7925_rx_check+0xa7/0xc0 [mt7925_common] mt76_dma_rx_poll+0x50d/0x790 [mt76] mt792x_poll_rx+0x52/0xe0 [mt792x_lib] Signed-off-by: Jiajia Liu --- Changes in v2: - use dev->wcid table instead of adding MT_WCID_FLAG_DRV_PUBLSH for wcid publish check suggested by Sean - subject and commit message update --- drivers/net/wireless/mediatek/mt76/mac80211.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wireless/mediatek/mt76/mac80211.c index 4ae5e4715a9c..b78b4cd206e0 100644 --- a/drivers/net/wireless/mediatek/mt76/mac80211.c +++ b/drivers/net/wireless/mediatek/mt76/mac80211.c @@ -1576,6 +1576,7 @@ mt76_sta_add(struct mt76_phy *phy, struct ieee80211_vif *vif, { struct mt76_wcid *wcid = (struct mt76_wcid *)sta->drv_priv; struct mt76_dev *dev = phy->dev; + struct mt76_wcid *published; int ret; int i; @@ -1595,11 +1596,19 @@ mt76_sta_add(struct mt76_phy *phy, struct ieee80211_vif *vif, mtxq->wcid = wcid->idx; } - ewma_signal_init(&wcid->rssi); - rcu_assign_pointer(dev->wcid[wcid->idx], wcid); + published = rcu_dereference_protected(dev->wcid[wcid->idx], + lockdep_is_held(&dev->mutex)); + if (published != wcid) { + WARN_ON_ONCE(published); + ewma_signal_init(&wcid->rssi); + rcu_assign_pointer(dev->wcid[wcid->idx], wcid); + mt76_wcid_init(wcid, phy->band_idx); + } else { + wcid->phy_idx = phy->band_idx; + } + phy->num_sta++; - mt76_wcid_init(wcid, phy->band_idx); out: mutex_unlock(&dev->mutex); -- 2.53.0