Re: [PATCH net] sch_dsmark: fix invalid skb_cow() usage

From: Eric Dumazet <redacted>
Date: Fri, 17 Mar 2017 08:05:28 -0700

From: Eric Dumazet <edumazet@google.com>

skb_cow(skb, sizeof(ip header)) is not very helpful in this context.

First we need to use pskb_may_pull() to make sure the ip header
is in skb linear part, then use skb_try_make_writable() to
address clones issues.

Fixes: 4c30719f4f55 ("[PKT_SCHED] dsmark: handle cloned and non-linear skb's")
Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied and queued up for -stable, thanks.