From dcd479e10a0510522a5d88b29b8f79ea3467d501 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 9 Oct 2020 14:17:11 +0200 Subject: [PATCH] mac80211: always wind down STA state When (for example) an IBSS station is pre-moved to AUTHORIZED before it's inserted, and then the insertion fails, we don't clean up the fast RX/TX states that might already have been created, since we don't go through all the state transitions again on the way down. Do that, if it hasn't been done already, when the station is freed. I considered only freeing the fast TX/RX state there, but we might add more state so it's more robust to wind down the state properly. Note that we warn if the station was ever inserted, it should have been properly cleaned up in that case, and the driver will probably not like things happening out of order. Reported-by: syzbot+2e293dbd67de2836ba42@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20201009141710.7223b322a955.I95bd08b9ad0e039c034927cce0b75beea38e059b@changeid Signed-off-by: Johannes Berg --- net/mac80211/sta_info.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index fb4f2b9..4fe284f 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -258,6 +258,24 @@ struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata, */ void sta_info_free(struct ieee80211_local *local, struct sta_info *sta) { + /* + * If we had used sta_info_pre_move_state() then we might not + * have gone through the state transitions down again, so do + * it here now (and warn if it's inserted). + * + * This will clear state such as fast TX/RX that may have been + * allocated during state transitions. + */ + while (sta->sta_state > IEEE80211_STA_NONE) { + int ret; + + WARN_ON_ONCE(test_sta_flag(sta, WLAN_STA_INSERTED)); + + ret = sta_info_move_state(sta, sta->sta_state - 1); + if (WARN_ONCE(ret, "sta_info_move_state() returned %d\n", ret)) + break; + } + if (sta->rate_ctrl) rate_control_free_sta(sta); -- 2.7.4