[34-longterm 195/260] Phonet: Correct header retrieval after pskb_may_pull

Paul Gortmaker
2011-01-02T07:24:58Z

From: Kumar Sanghvi <kumar.sanghvi@stericsson.com>

commit a91e7d471e2e384035b9746ea707ccdcd353f5dd upstream.

Retrieve the header after doing pskb_may_pull since, pskb_may_pull
could change the buffer structure.

This is based on the comment given by Eric Dumazet on Phonet
Pipe controller patch for a similar problem.

Signed-off-by: Kumar Sanghvi <kumar.sanghvi@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
net/phonet/pep.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/net/phonet/pep.c b/net/phonet/pep.c
index e2a9576..dc1e8ae 100644
--- a/net/phonet/pep.c
+++ b/net/phonet/pep.c
@@ -225,12 +225,13 @@ static void pipe_grant_credits(struct sock *sk)
static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
{
struct pep_sock *pn = pep_sk(sk);
- struct pnpipehdr *hdr = pnp_hdr(skb);
+ struct pnpipehdr *hdr;
int wake = 0;

if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
return -EINVAL;

+ hdr = pnp_hdr(skb);
if (hdr->data[0] != PN_PEP_TYPE_COMMON) {
LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n",
(unsigned)hdr->data[0]);
--
1.7.3.3