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| author | Eric Dumazet <edumazet@google.com> | 2017-03-17 08:05:28 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-03-21 17:21:27 -0700 |
| commit | aea92fb2e09e29653b023d4254ac9fbf94221538 (patch) | |
| tree | 146bf8ca4cb9b88ca710c379a317e7135db667f2 /net/sched/sch_dsmark.c | |
| parent | 09050957fae896e001498af1aa35c446a11cb47d (diff) | |
| download | linux-aea92fb2e09e29653b023d4254ac9fbf94221538.tar.gz linux-aea92fb2e09e29653b023d4254ac9fbf94221538.tar.bz2 linux-aea92fb2e09e29653b023d4254ac9fbf94221538.zip | |
sch_dsmark: fix invalid skb_cow() usage
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>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sched/sch_dsmark.c')
| -rw-r--r-- | net/sched/sch_dsmark.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/sched/sch_dsmark.c b/net/sched/sch_dsmark.c index 802ac7c2e5e8..5334e309f17f 100644 --- a/net/sched/sch_dsmark.c +++ b/net/sched/sch_dsmark.c @@ -201,9 +201,13 @@ static int dsmark_enqueue(struct sk_buff *skb, struct Qdisc *sch, pr_debug("%s(skb %p,sch %p,[qdisc %p])\n", __func__, skb, sch, p); if (p->set_tc_index) { + int wlen = skb_network_offset(skb); + switch (tc_skb_protocol(skb)) { case htons(ETH_P_IP): - if (skb_cow_head(skb, sizeof(struct iphdr))) + wlen += sizeof(struct iphdr); + if (!pskb_may_pull(skb, wlen) || + skb_try_make_writable(skb, wlen)) goto drop; skb->tc_index = ipv4_get_dsfield(ip_hdr(skb)) @@ -211,7 +215,9 @@ static int dsmark_enqueue(struct sk_buff *skb, struct Qdisc *sch, break; case htons(ETH_P_IPV6): - if (skb_cow_head(skb, sizeof(struct ipv6hdr))) + wlen += sizeof(struct ipv6hdr); + if (!pskb_may_pull(skb, wlen) || + skb_try_make_writable(skb, wlen)) goto drop; skb->tc_index = ipv6_get_dsfield(ipv6_hdr(skb)) |