diff options
author | Eric Dumazet <edumazet@google.com> | 2017-03-17 08:05:28 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-25 14:22:10 +0100 |
commit | ffde339b95f5729e9d57ba0802b50a611854b728 (patch) | |
tree | 1b3a25c5c67690d00359b5ab819b7939eaf7ee82 | |
parent | 4bf8a4f179ed5c9775f0970fc652cc04c0994186 (diff) |
sch_dsmark: fix invalid skb_cow() usage
[ Upstream commit aea92fb2e09e29653b023d4254ac9fbf94221538 ]
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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-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 d0dff0cd8186..cce4e6ada7fa 100644 --- a/net/sched/sch_dsmark.c +++ b/net/sched/sch_dsmark.c @@ -199,9 +199,13 @@ 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)) @@ -209,7 +213,9 @@ 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)) |