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| author | Oliver Hartkopp <socketcan@hartkopp.net> | 2010-08-03 00:31:48 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-08-03 00:31:48 -0700 |
| commit | cff0d6e6edac7672b3f915bb4fb59f279243b7f9 (patch) | |
| tree | a12b08344380a9f02c9d043b176b82e921266d6e | |
| parent | 3578b0c8abc7bdb4f02152ce5db7e09d484c6866 (diff) | |
| download | lwn-cff0d6e6edac7672b3f915bb4fb59f279243b7f9.tar.gz lwn-cff0d6e6edac7672b3f915bb4fb59f279243b7f9.zip | |
can-raw: Fix skb_orphan_try handling
Commit fc6055a5ba31e2c14e36e8939f9bf2b6d586a7f5 (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>
| -rw-r--r-- | include/linux/skbuff.h | 4 | ||||
| -rw-r--r-- | net/can/raw.c | 4 |
2 files changed, 7 insertions, 1 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index d89876b806a0..d20d9e7a9bbd 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -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; }; diff --git a/net/can/raw.c b/net/can/raw.c index ccfe633eec8e..a10e3338f084 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -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; |