macsec: avoid use-after-free in macsec_handle_frame()

De-referencing skb after call to gro_cells_receive() is not allowed.
We need to fetch skb->len earlier.

Fixes: 5491e7c6b1 ("macsec: enable GRO and RPS on macsec devices")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Eric Dumazet 2020-10-07 01:42:46 -07:00 committed by Jakub Kicinski
parent 47dda78671
commit c7cc9200e9

View File

@ -1077,6 +1077,7 @@ static rx_handler_result_t macsec_handle_frame(struct sk_buff **pskb)
struct macsec_rx_sa *rx_sa;
struct macsec_rxh_data *rxd;
struct macsec_dev *macsec;
unsigned int len;
sci_t sci;
u32 hdr_pn;
bool cbit;
@ -1232,9 +1233,10 @@ static rx_handler_result_t macsec_handle_frame(struct sk_buff **pskb)
macsec_rxsc_put(rx_sc);
skb_orphan(skb);
len = skb->len;
ret = gro_cells_receive(&macsec->gro_cells, skb);
if (ret == NET_RX_SUCCESS)
count_rx(dev, skb->len);
count_rx(dev, len);
else
macsec->secy.netdev->stats.rx_dropped++;