[PATCH bpf v2] bpf: clear skb->tstamp in bpf_redirect when necessary

From: Lorenz Bauer
Date: Fri Dec 13 2019 - 13:08:59 EST

Redirecting a packet from ingress to egress by using bpf_redirect
breaks if the egress interface has an fq qdisc installed. This is the same
problem as fixed in 'commit 8203e2d844d3 ("net: clear skb->tstamp in forwarding paths")

Clear skb->tstamp when redirecting into the egress path.

Fixes: 80b14dee2bea ("net: Add a new socket option for a future transmit time.")
Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: Lorenz Bauer <lmb@xxxxxxxxxxxxxx>
net/core/filter.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/net/core/filter.c b/net/core/filter.c
index f1e703eed3d2..d914257763b5 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2055,6 +2055,7 @@ static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)

skb->dev = dev;
+ skb->tstamp = 0;

ret = dev_queue_xmit(skb);