| Message ID | 1557372018-18544-1-git-send-email-jasowang@redhat.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net,V3,1/2] tuntap: fix dividing by zero in ebpf queue selection | expand |
On 5/8/19 11:20 PM, Jason Wang wrote: > We need check if tun->numqueues is zero (e.g for the persist device) > before trying to use it for modular arithmetic. > > Reported-by: Eric Dumazet <eric.dumazet@gmail.com> > Fixes: 96f84061620c6("tun: add eBPF based queue selection method") > Signed-off-by: Jason Wang <jasowang@redhat.com> > --- Reviewed-by: Eric Dumazet <edumazet@google.com> Thanks.
From: Jason Wang <jasowang@redhat.com> Date: Wed, 8 May 2019 23:20:17 -0400 > We need check if tun->numqueues is zero (e.g for the persist device) > before trying to use it for modular arithmetic. > > Reported-by: Eric Dumazet <eric.dumazet@gmail.com> > Fixes: 96f84061620c6("tun: add eBPF based queue selection method") > Signed-off-by: Jason Wang <jasowang@redhat.com> Applied and queued up for -stable.
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index e9ca1c0..dc62fc3 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -596,13 +596,18 @@ static u16 tun_automq_select_queue(struct tun_struct *tun, struct sk_buff *skb) static u16 tun_ebpf_select_queue(struct tun_struct *tun, struct sk_buff *skb) { struct tun_prog *prog; + u32 numqueues; u16 ret = 0; + numqueues = READ_ONCE(tun->numqueues); + if (!numqueues) + return 0; + prog = rcu_dereference(tun->steering_prog); if (prog) ret = bpf_prog_run_clear_cb(prog->prog, skb); - return ret % tun->numqueues; + return ret % numqueues; } static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb,
We need check if tun->numqueues is zero (e.g for the persist device) before trying to use it for modular arithmetic. Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Fixes: 96f84061620c6("tun: add eBPF based queue selection method") Signed-off-by: Jason Wang <jasowang@redhat.com> --- drivers/net/tun.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)