diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-09-11 13:11:12 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-09-11 22:20:43 -0400 |
| commit | bdfc87f7d1e253e0a61e2fc6a75ea9d76f7fc03a (patch) | |
| tree | cfaf95ce5aa47eee32b503aa20896c79e5c8f7c2 | |
| parent | b48d6f8bed430922f78f648d1f73f7c1591e472c (diff) | |
| download | linux-bdfc87f7d1e253e0a61e2fc6a75ea9d76f7fc03a.tar.bz2 | |
net-sched: sch_cbq: avoid infinite loop
Its possible to setup a bad cbq configuration leading to
an infinite loop in cbq_classify()
DEV_OUT=eth0
ICMP="match ip protocol 1 0xff"
U32="protocol ip u32"
DST="match ip dst"
tc qdisc add dev $DEV_OUT root handle 1: cbq avpkt 1000 \
bandwidth 100mbit
tc class add dev $DEV_OUT parent 1: classid 1:1 cbq \
rate 512kbit allot 1500 prio 5 bounded isolated
tc filter add dev $DEV_OUT parent 1: prio 3 $U32 \
$ICMP $DST 192.168.3.234 flowid 1:
Reported-by: Denys Fedoryschenko <denys@visp.net.lb>
Tested-by: Denys Fedoryschenko <denys@visp.net.lb>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/sched/sch_cbq.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c index 6aabd77d1cfd..564b9fc8efd3 100644 --- a/net/sched/sch_cbq.c +++ b/net/sched/sch_cbq.c @@ -250,10 +250,11 @@ cbq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) else if ((cl = defmap[res.classid & TC_PRIO_MAX]) == NULL) cl = defmap[TC_PRIO_BESTEFFORT]; - if (cl == NULL || cl->level >= head->level) + if (cl == NULL) goto fallback; } - + if (cl->level >= head->level) + goto fallback; #ifdef CONFIG_NET_CLS_ACT switch (result) { case TC_ACT_QUEUED: |