diff options
author | Daniel Borkmann <daniel@iogearbox.net> | 2016-02-19 23:05:25 +0100 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2016-02-21 22:07:10 -0500 |
commit | 3697649ff29e0f647565eed04b27a7779c646a22 (patch) | |
tree | f6777555e1879ba3af5cb96673f3674bb72ca7c0 /net/sched/act_nat.c | |
parent | 21cafc1dc2da999dabc5ed7aa94230454471fcf0 (diff) | |
download | lwn-3697649ff29e0f647565eed04b27a7779c646a22.tar.gz lwn-3697649ff29e0f647565eed04b27a7779c646a22.zip |
bpf: try harder on clones when writing into skb
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>
Diffstat (limited to 'net/sched/act_nat.c')
-rw-r--r-- | net/sched/act_nat.c | 18 |
1 files changed, 5 insertions, 13 deletions
diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c index b7c4ead8b5a8..27607b863aba 100644 --- a/net/sched/act_nat.c +++ b/net/sched/act_nat.c @@ -126,9 +126,7 @@ static int tcf_nat(struct sk_buff *skb, const struct tc_action *a, addr = iph->daddr; if (!((old_addr ^ addr) & mask)) { - if (skb_cloned(skb) && - !skb_clone_writable(skb, sizeof(*iph) + noff) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) + if (skb_try_make_writable(skb, sizeof(*iph) + noff)) goto drop; new_addr &= mask; @@ -156,9 +154,7 @@ static int tcf_nat(struct sk_buff *skb, const struct tc_action *a, struct tcphdr *tcph; if (!pskb_may_pull(skb, ihl + sizeof(*tcph) + noff) || - (skb_cloned(skb) && - !skb_clone_writable(skb, ihl + sizeof(*tcph) + noff) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) + skb_try_make_writable(skb, ihl + sizeof(*tcph) + noff)) goto drop; tcph = (void *)(skb_network_header(skb) + ihl); @@ -171,9 +167,7 @@ static int tcf_nat(struct sk_buff *skb, const struct tc_action *a, struct udphdr *udph; if (!pskb_may_pull(skb, ihl + sizeof(*udph) + noff) || - (skb_cloned(skb) && - !skb_clone_writable(skb, ihl + sizeof(*udph) + noff) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) + skb_try_make_writable(skb, ihl + sizeof(*udph) + noff)) goto drop; udph = (void *)(skb_network_header(skb) + ihl); @@ -213,10 +207,8 @@ static int tcf_nat(struct sk_buff *skb, const struct tc_action *a, if ((old_addr ^ addr) & mask) break; - if (skb_cloned(skb) && - !skb_clone_writable(skb, ihl + sizeof(*icmph) + - sizeof(*iph) + noff) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) + if (skb_try_make_writable(skb, ihl + sizeof(*icmph) + + sizeof(*iph) + noff)) goto drop; icmph = (void *)(skb_network_header(skb) + ihl); |