In the Linux kernel, the following vulnerability has been resolved:net_sched: sch_sfq: fix a potential crash on gso_skb handlingSFQ has an assumption of always being able to queue at least one packet.However, after the blamed commit, sch->q.len can be inflated by packetsin sch->gso_skb, and an enqueue() on an empty SFQ qdisc can be followedby an immediate drop.Fix sfq_drop() to properly clear q->tail in this situation.ip netns add lbip link add dev to-lb type veth peer name in-lb netns lbethtool -K to-lb tso off # force qdisc to requeue gso_skbip netns exec lb ethtool -K in-lb gro on # enable NAPIip link set dev to-lb upip -netns lb link set dev in-lb upip addr add dev to-lb 192.168.20.1/24ip -netns lb addr add dev in-lb 192.168.20.2/24tc qdisc replace dev to-lb root sfq limit 100ip netns exec lb netservernetperf -H 192.168.20.2 -l 100 &netperf -H 192.168.20.2 -l 100 &netperf -H 192.168.20.2 -l 100 &netperf -H 192.168.20.2 -l 100 &
No PoCs from references.
- https://github.com/w4zu/Debian_security