net_sched: sfq: always randomize hash perturbation
commit02a9098ede0dc7e28c16a03fa7fba86a05219478
authorEric Dumazet <eric.dumazet@gmail.com>
Wed, 4 Jan 2012 06:23:01 +0000 (4 06:23 +0000)
committerDavid S. Miller <davem@davemloft.net>
Wed, 4 Jan 2012 19:12:48 +0000 (4 14:12 -0500)
tree689df90e53168b72b8f2f418853830747bba8e90
parentbd16a6cce2a7f169b559abc5672fd2c66e91fb36
net_sched: sfq: always randomize hash perturbation

SFQ q->perturbation is used in sfq_hash() as an input to Jenkins hash.

We currently randomize this 32bit value only if a perturbation timer is
setup.

Its much better to always initialize it to defeat attackers, or else
they can predict very well what kind of packets they have to forge to
hit a particular flow.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/sched/sch_sfq.c