diff options
| author | Toke Høiland-Jørgensen <toke@toke.dk> | 2022-08-31 11:21:03 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-08-31 14:20:08 -0700 |
| commit | 90fabae8a2c225c4e4936723c38857887edde5cc (patch) | |
| tree | 2a06d39adc366c6971756b45b181a2a019c6cb9a /net | |
| parent | 5a3a59981027b53ec0f729ad76a43ce2b64ad968 (diff) | |
sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb
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 <toke@toke.dk>
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-18231
Link: https://lore.kernel.org/r/20220831092103.442868-1-toke@toke.dk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/sched/sch_cake.c | 4 |
1 files changed, 3 insertions, 1 deletions
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) |