4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Felix Fietkau nbd@nbd.name
commit 9d0f50b80222dc273e67e4e14410fcfa4130a90c upstream.
Some drivers use IEEE80211_KEY_FLAG_SW_MGMT_TX to indicate that management frames need to be software encrypted. Since normal data packets are still encrypted by the hardware, crypto_tx_tailroom_needed_cnt gets decremented after key upload to hw. This can lead to passing skbs to ccmp_encrypt_skb, which don't have the necessary tailroom for software encryption.
Change the code to add tailroom for encrypted management packets, even if crypto_tx_tailroom_needed_cnt is 0.
Cc: stable@vger.kernel.org Signed-off-by: Felix Fietkau nbd@nbd.name Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/mac80211/tx.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
--- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1938,9 +1938,16 @@ static int ieee80211_skb_resize(struct i int head_need, bool may_encrypt) { struct ieee80211_local *local = sdata->local; + struct ieee80211_hdr *hdr; + bool enc_tailroom; int tail_need = 0;
- if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) { + hdr = (struct ieee80211_hdr *) skb->data; + enc_tailroom = may_encrypt && + (sdata->crypto_tx_tailroom_needed_cnt || + ieee80211_is_mgmt(hdr->frame_control)); + + if (enc_tailroom) { tail_need = IEEE80211_ENCRYPT_TAILROOM; tail_need -= skb_tailroom(skb); tail_need = max_t(int, tail_need, 0); @@ -1948,8 +1955,7 @@ static int ieee80211_skb_resize(struct i
if (skb_cloned(skb) && (!ieee80211_hw_check(&local->hw, SUPPORTS_CLONED_SKBS) || - !skb_clone_writable(skb, ETH_HLEN) || - (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt))) + !skb_clone_writable(skb, ETH_HLEN) || enc_tailroom)) I802_DEBUG_INC(local->tx_expand_skb_head_cloned); else if (head_need || tail_need) I802_DEBUG_INC(local->tx_expand_skb_head);