| Message ID | 1555399480-30537-1-git-send-email-bperumal@codeaurora.org (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Johannes Berg |
| Headers | show |
| Series | mac80211: Fix kernel panic due to use of txq after free | expand |
Bhagavathi Perumal S <bperumal@codeaurora.org> writes: > The txq of vif is added to active_txqs list for ATF TXQ scheduling > in the function ieee80211_queue_skb(), but it was not properly removed > before freeing the txq object. It was causing use after free of the txq > objects from the active_txqs list, result was kernel panic > due to invalid memory access. > > Fix kernel invalid memory access by properly removing txq object > from active_txqs list before free the object. > > Signed-off-by: Bhagavathi Perumal S <bperumal@codeaurora.org> Nice catch, thanks! Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> This should probably have a fixes tag: Fixes: 1866760096bf ("mac80211: Add TXQ scheduling API") -Toke
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index 94459b2..410685d 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -1907,6 +1907,9 @@ void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata) list_del_rcu(&sdata->list); mutex_unlock(&sdata->local->iflist_mtx); + if (sdata->vif.txq) + ieee80211_txq_purge(sdata->local, to_txq_info(sdata->vif.txq)); + synchronize_rcu(); if (sdata->dev) {
The txq of vif is added to active_txqs list for ATF TXQ scheduling in the function ieee80211_queue_skb(), but it was not properly removed before freeing the txq object. It was causing use after free of the txq objects from the active_txqs list, result was kernel panic due to invalid memory access. Fix kernel invalid memory access by properly removing txq object from active_txqs list before free the object. Signed-off-by: Bhagavathi Perumal S <bperumal@codeaurora.org> --- net/mac80211/iface.c | 3 +++ 1 file changed, 3 insertions(+)