From: Shannon Nelson snelson@pensando.io
[ Upstream commit d2c21422323b06938b3c070361dc544f047489d7 ]
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: 0f3154e6bcb3 ("ionic: Add Tx and Rx handling") Signed-off-by: Shannon Nelson snelson@pensando.io Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/pensando/ionic/ionic_txrx.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c index a81feffb09b8..909eca14f647 100644 --- a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c +++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c @@ -1077,15 +1077,17 @@ 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); @@ -1094,8 +1096,7 @@ 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)