When the GSO splitting feature of sch_cake is enabled, GSO superpackets
will be broken up and the resulting segments enqueued in place of the
original skb. In this case, CAKE calls consume_skb() on the original skb,
but still returns NET_XMIT_SUCCESS. This can confuse parent qdiscs into
assuming the original skb still exists, when it really has been freed. Fix
this by adding the __NET_XMIT_STOLEN flag to the return value in this case.
Fixes: 0c850344d388 ("sch_cake: Conditionally split GSO segments")
Signed-off-by: Toke Høiland-Jørgensen <t...@toke.dk>
---
net/sched/sch_cake.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c
index a43a58a73d09..a04928082e4a 100644
--- a/net/sched/sch_cake.c
+++ b/net/sched/sch_cake.c
@@ -1713,6 +1713,7 @@ static s32 cake_enqueue(struct sk_buff *skb, struct Qdisc
*sch,
}
idx--;
flow = &b->flows[idx];
+ ret = NET_XMIT_SUCCESS;
/* ensure shaper state isn't stale */
if (!b->tin_backlog) {
@@ -1771,6 +1772,7 @@ static s32 cake_enqueue(struct sk_buff *skb, struct Qdisc
*sch,
qdisc_tree_reduce_backlog(sch, 1-numsegs, len-slen);
consume_skb(skb);
+ ret |= __NET_XMIT_STOLEN;
} else {
/* not splitting */
cobalt_set_enqueue_time(skb, now);
@@ -1904,7 +1906,7 @@ static s32 cake_enqueue(struct sk_buff *skb, struct Qdisc
*sch,
}
b->drop_overlimit += dropped;
}
- return NET_XMIT_SUCCESS;
+ return ret;
}
static struct sk_buff *cake_dequeue_one(struct Qdisc *sch)
--
2.37.2
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