can-raw: Fix skb_orphan_try handling

Commit fc6055a5ba (net: Introduce
skb_orphan_try()) allows an early orphan of the skb and takes care on
tx timestamping, which needs the sk-reference in the skb on driver level.
So does the can-raw socket, which has not been taken into account here.

The patch below adds a 'prevent_sk_orphan' bit in the skb tx shared info,
which fixes the problem discovered by Matthias Fuchs here:

      http://marc.info/?t=128030411900003&r=1&w=2

Even if it's not a primary tx timestamp topic it fits well into some skb
shared tx context. Or should be find a different place for the information to
protect the sk reference until it reaches the driver level?

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Oliver Hartkopp 2010-08-03 00:31:48 -07:00 committed by David S. Miller
parent 3578b0c8ab
commit cff0d6e6ed
2 changed files with 7 additions and 1 deletions

View File

@ -169,6 +169,7 @@ struct skb_shared_hwtstamps {
* @software: generate software time stamp
* @in_progress: device driver is going to provide
* hardware time stamp
* @prevent_sk_orphan: make sk reference available on driver level
* @flags: all shared_tx flags
*
* These flags are attached to packets as part of the
@ -178,7 +179,8 @@ union skb_shared_tx {
struct {
__u8 hardware:1,
software:1,
in_progress:1;
in_progress:1,
prevent_sk_orphan:1;
};
__u8 flags;
};

View File

@ -650,6 +650,10 @@ static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
err = sock_tx_timestamp(msg, sk, skb_tx(skb));
if (err < 0)
goto free_skb;
/* to be able to check the received tx sock reference in raw_rcv() */
skb_tx(skb)->prevent_sk_orphan = 1;
skb->dev = dev;
skb->sk = sk;