[PATCH 5.11 164/254] ionic: linearize tso skb with too many frags
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-03-29 08:59:25
Also in:
lkml
Subsystem:
networking drivers, pensando ethernet drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Brett Creeley, Linus Torvalds
From: Shannon Nelson <redacted>
[ 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 <redacted>
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 ac4cd5d82e69..b7601cadcb8c 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c@@ -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)
--
2.30.1