diff options
| author | Eason Lai <Eason.Lai@mediatek.com> | 2026-07-01 09:06:54 +0800 |
|---|---|---|
| committer | Felix Fietkau <nbd@nbd.name> | 2026-07-31 12:25:38 +0000 |
| commit | 217f9e7bb02558759be9d9ecfe532e9708741c50 (patch) | |
| tree | 6397d5b9039333fb6d28db0ea66b4cbeb09fe680 | |
| parent | 3c004f73d68b415d231189b75a3cff1582a17e90 (diff) | |
wifi: mt76: mt792x: fix use-after-free in mt76_rx_poll_complete
A use-after-free issue occurs in mt76_rx_poll_complete due to a race
condition. The STA has already been removed, but the rx_status still
had a pointer to the wcid in the STA.
Set the links' wcid pointers to be NULL for a MLD in
mt7925_sta_pre_rcu_remove()
BUG: KASAN: invalid-access in mt76_rx_poll_complete+0x280/0x470
Call trace:
dump_backtrace+0xec/0x128
show_stack+0x18/0x28
dump_stack_lvl+0x40/0xc8
print_report+0x1b8/0x710
kasan_report+0xe0/0x144
do_bad_area+0x120/0x260
do_tag_check_fault+0x20/0x34
do_mem_abort+0x54/0xa8
el1_abort+0x3c/0x5c
el1h_64_sync_handler+0x40/0xcc
el1h_64_sync+0x7c/0x80
mt76_rx_poll_complete+0x280/0x470
mt76_dma_rx_poll+0x114/0x51c
mt792x_poll_rx+0x60/0xf8
napi_threaded_poll_loop+0xe0/0x450
napi_threaded_poll+0x80/0x9c
kthread+0x11c/0x158
ret_from_fork+0x10/0x20
Fixes: c948b5da6bbe ("wifi: mt76: mt7925: add Mediatek Wi-Fi7 driver for mt7925 chips")
Signed-off-by: Eason Lai <Eason.Lai@mediatek.com>
Link: https://patch.msgid.link/20260701010654.956863-1-eason.lai@mediatek.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>
| -rw-r--r-- | drivers/net/wireless/mediatek/mt76/mt7925/main.c | 36 |
1 files changed, 35 insertions, 1 deletions
diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/main.c b/drivers/net/wireless/mediatek/mt76/mt7925/main.c index 6be5b60b9bac..abb56f6fea77 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7925/main.c +++ b/drivers/net/wireless/mediatek/mt76/mt7925/main.c @@ -2661,6 +2661,40 @@ static int mt7925_nan_peer_sched_changed(struct ieee80211_hw *hw, return err; } +static void mt7925_sta_pre_rcu_remove(struct ieee80211_hw *hw, + struct ieee80211_vif *vif, + struct ieee80211_sta *sta) +{ + struct mt76_phy *phy = hw->priv; + struct mt76_dev *dev = phy->dev; + struct mt76_wcid *wcid = (struct mt76_wcid *)sta->drv_priv; + + mutex_lock(&dev->mutex); + spin_lock_bh(&dev->status_lock); + + if (ieee80211_vif_is_mld(vif)) { + struct mt792x_sta *msta = (struct mt792x_sta *)sta->drv_priv; + struct mt792x_vif *mvif = (struct mt792x_vif *)vif->drv_priv; + unsigned long valid = mvif->valid_links; + struct mt792x_link_sta *mlink; + unsigned int link_id; + + for_each_set_bit(link_id, &valid, IEEE80211_MLD_MAX_NUM_LINKS) { + mlink = mt792x_sta_to_link(msta, link_id); + if (!mlink || !mlink->wcid.sta) + continue; + if (mlink->wcid.idx < ARRAY_SIZE(dev->wcid)) + rcu_assign_pointer(dev->wcid[mlink->wcid.idx], + NULL); + } + } else { + rcu_assign_pointer(dev->wcid[wcid->idx], NULL); + } + + spin_unlock_bh(&dev->status_lock); + mutex_unlock(&dev->mutex); +} + const struct ieee80211_ops mt7925_ops = { .tx = mt792x_tx, .start = mt7925_start, @@ -2673,7 +2707,7 @@ const struct ieee80211_ops mt7925_ops = { .start_ap = mt7925_start_ap, .stop_ap = mt7925_stop_ap, .sta_state = mt76_sta_state, - .sta_pre_rcu_remove = mt76_sta_pre_rcu_remove, + .sta_pre_rcu_remove = mt7925_sta_pre_rcu_remove, .set_key = mt7925_set_key, .sta_set_decap_offload = mt7925_sta_set_decap_offload, #if IS_ENABLED(CONFIG_IPV6) |