diff options
| author | Haishuang Yan <yanhaishuang@cmss.chinamobile.com> | 2016-04-03 22:09:24 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-20 15:40:43 +0900 |
| commit | 80f9b401a79b6c932a042e0fc98ec21801d325bd (patch) | |
| tree | 063e3c2d2376c5b605986a29b23b19ab6cad63c8 /net | |
| parent | 0123df6309868720d6bf9b6da74f612151766637 (diff) | |
| download | lwn-80f9b401a79b6c932a042e0fc98ec21801d325bd.tar.gz lwn-80f9b401a79b6c932a042e0fc98ec21801d325bd.zip | |
ipv6: l2tp: fix a potential issue in l2tp_ip6_recv
[ Upstream commit be447f305494e019dfc37ea4cdf3b0e4200b4eba ]
pskb_may_pull() can change skb->data, so we have to load ptr/optr at the
right place.
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/l2tp/l2tp_ip6.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c index 7704ea9502fd..15f1e4479926 100644 --- a/net/l2tp/l2tp_ip6.c +++ b/net/l2tp/l2tp_ip6.c @@ -135,12 +135,11 @@ static int l2tp_ip6_recv(struct sk_buff *skb) struct l2tp_tunnel *tunnel = NULL; int length; - /* Point to L2TP header */ - optr = ptr = skb->data; - if (!pskb_may_pull(skb, 4)) goto discard; + /* Point to L2TP header */ + optr = ptr = skb->data; session_id = ntohl(*((__be32 *) ptr)); ptr += 4; @@ -168,6 +167,9 @@ static int l2tp_ip6_recv(struct sk_buff *skb) if (!pskb_may_pull(skb, length)) goto discard; + /* Point to L2TP header */ + optr = ptr = skb->data; + ptr += 4; pr_debug("%s: ip recv\n", tunnel->name); print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, ptr, length); } |