From d70d6222db05172d02a821ee97b5651f4091a891 Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <daniel@iogearbox.net>
Date: Fri, 19 Feb 2016 23:05:25 +0100
Subject: [PATCH] bpf: try harder on clones when writing into skb

commit 3697649ff29e0f647565eed04b27a7779c646a22 upstream.

When we're dealing with clones and the area is not writeable, try
harder and get a copy via pskb_expand_head(). Replace also other
occurences in tc actions with the new skb_try_make_writable().

Reported-by: Ashhad Sheikh <ashhadsheikh394@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: drop changes to bpf; only tc actions need fixing]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
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