Commit d2c21422 authored by Shannon Nelson's avatar Shannon Nelson Committed by David S. Miller
Browse files

ionic: linearize tso skb with too many frags 



We were linearizing non-TSO skbs that had too many frags, but
we weren't checking number of frags on TSO skbs.  This could
lead to a bad page reference when we received a TSO skb with
more frags than the Tx descriptor could support.

v2: use gso_segs rather than yet another division
    don't rework the check on the nr_frags

Fixes: 0f3154e6 ("ionic: Add Tx and Rx handling")
Signed-off-by: default avatarShannon Nelson <snelson@pensando.io>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent fc649670

drivers/net/ethernet/pensando/ionic/ionic_txrx.c

+7 −6
Original line number Diff line number Diff line
@@ -1079,15 +1079,17 @@ static int ionic_tx_descs_needed(struct ionic_queue *q, struct sk_buff *skb) 
{

	int sg_elems = q->lif->qtype_info[IONIC_QTYPE_TXQ].max_sg_elems;

	struct ionic_tx_stats *stats = q_to_tx_stats(q);

	int ndescs;

	int err;



	/* If TSO, need roundup(skb->len/mss) descs */

	/* Each desc is mss long max, so a descriptor for each gso_seg */

	if (skb_is_gso(skb))

		return (skb->len / skb_shinfo(skb)->gso_size) + 1;

		ndescs = skb_shinfo(skb)->gso_segs;

	else

		ndescs = 1;



	/* If non-TSO, just need 1 desc and nr_frags sg elems */

	if (skb_shinfo(skb)->nr_frags <= sg_elems)

		return 1;

		return ndescs;



	/* Too many frags, so linearize */

	err = skb_linearize(skb);
@@ -1096,8 +1098,7 @@ static int ionic_tx_descs_needed(struct ionic_queue *q, struct sk_buff *skb) 


	stats->linearize++;



	/* Need 1 desc and zero sg elems */

	return 1;

	return ndescs;

}



static int ionic_maybe_stop_tx(struct ionic_queue *q, int ndescs)