[3.19.y-ckt stable] Patch "can: fix loss of CAN frames in raw_rcv" has been added to staging queue

[Kamal Mostafa]

On Thu, 2015-07-16 at 07:03 +0200, Oliver Hartkopp wrote:
> Hello Kamal,
> 
> this patch is only relevant for v4.1.x where the problematic commit
> 514ac99c64b "can: fix multiple delivery of a single CAN frame for overlapping
> CAN filters" has been introduced.
> 
> So we can omit this patch below for 3.19.y-ckt stable as it does not fix 
> anything there.
> 
> We just missed to add a marker '# v4.1' in that fix.
> 
> Sorry for the noise.

No worries -- I'll drop this patch from 3.19-stable.

Thanks Oliver!

 -Kamal


> Best regards,
> Oliver
> 
> 
> On 16.07.2015 03:01, Kamal Mostafa wrote:
> > This is a note to let you know that I have just added a patch titled
> >
> >      can: fix loss of CAN frames in raw_rcv
> >
> > to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree
> > which can be found at:
> >
> >      http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue
> >
> > This patch is scheduled to be released in version 3.19.y-ckt4.
> >
> > If you, or anyone else, feels it should not be added to this tree, please
> > reply to this email.
> >
> > For more information about the 3.19.y-ckt tree, see
> > https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
> >
> > Thanks.
> > -Kamal
> >
> > ------
> >
> >  From 42fd9bd1b9ba6558f060f9077070f71a9f31de90 Mon Sep 17 00:00:00 2001
> > From: Oliver Hartkopp <socketcan at hartkopp.net>
> > Date: Sun, 21 Jun 2015 18:50:44 +0200
> > Subject: can: fix loss of CAN frames in raw_rcv
> >
> > commit 36c01245eb8046c16eee6431e7dbfbb302635fa8 upstream.
> >
> > As reported by Manfred Schlaegl here
> >
> >     http://marc.info/?l=linux-netdev&m=143482089824232&w=2
> >
> > commit 514ac99c64b "can: fix multiple delivery of a single CAN frame for
> > overlapping CAN filters" requires the skb->tstamp to be set to check for
> > identical CAN skbs.
> >
> > As net timestamping is influenced by several players (netstamp_needed and
> > netdev_tstamp_prequeue) Manfred missed a proper timestamp which leads to
> > CAN frame loss.
> >
> > As skb timestamping became now mandatory for CAN related skbs this patch
> > makes sure that received CAN skbs always have a proper timestamp set.
> > Maybe there's a better solution in the future but this patch fixes the
> > CAN frame loss so far.
> >
> > Reported-by: Manfred Schlaegl <manfred.schlaegl at gmx.at>
> > Signed-off-by: Oliver Hartkopp <socketcan at hartkopp.net>
> > Signed-off-by: Marc Kleine-Budde <mkl at pengutronix.de>
> > Signed-off-by: Kamal Mostafa <kamal at canonical.com>
> > ---
> >   drivers/net/can/dev.c   | 5 +++++
> >   drivers/net/can/slcan.c | 1 +
> >   drivers/net/can/vcan.c  | 3 +++
> >   net/can/af_can.c        | 6 +++++-
> >   4 files changed, 14 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
> > index 62ca0e8..44fc75f 100644
> > --- a/drivers/net/can/dev.c
> > +++ b/drivers/net/can/dev.c
> > @@ -438,6 +438,9 @@ unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx)
> >   		struct can_frame *cf = (struct can_frame *)skb->data;
> >   		u8 dlc = cf->can_dlc;
> >
> > +		if (!(skb->tstamp.tv64))
> > +			__net_timestamp(skb);
> > +
> >   		netif_rx(priv->echo_skb[idx]);
> >   		priv->echo_skb[idx] = NULL;
> >
> > @@ -574,6 +577,7 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
> >   	if (unlikely(!skb))
> >   		return NULL;
> >
> > +	__net_timestamp(skb);
> >   	skb->protocol = htons(ETH_P_CAN);
> >   	skb->pkt_type = PACKET_BROADCAST;
> >   	skb->ip_summed = CHECKSUM_UNNECESSARY;
> > @@ -602,6 +606,7 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev,
> >   	if (unlikely(!skb))
> >   		return NULL;
> >
> > +	__net_timestamp(skb);
> >   	skb->protocol = htons(ETH_P_CANFD);
> >   	skb->pkt_type = PACKET_BROADCAST;
> >   	skb->ip_summed = CHECKSUM_UNNECESSARY;
> > diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
> > index c837eb9..f64f529 100644
> > --- a/drivers/net/can/slcan.c
> > +++ b/drivers/net/can/slcan.c
> > @@ -207,6 +207,7 @@ static void slc_bump(struct slcan *sl)
> >   	if (!skb)
> >   		return;
> >
> > +	__net_timestamp(skb);
> >   	skb->dev = sl->dev;
> >   	skb->protocol = htons(ETH_P_CAN);
> >   	skb->pkt_type = PACKET_BROADCAST;
> > diff --git a/drivers/net/can/vcan.c b/drivers/net/can/vcan.c
> > index 674f367..0ce868d 100644
> > --- a/drivers/net/can/vcan.c
> > +++ b/drivers/net/can/vcan.c
> > @@ -78,6 +78,9 @@ static void vcan_rx(struct sk_buff *skb, struct net_device *dev)
> >   	skb->dev       = dev;
> >   	skb->ip_summed = CHECKSUM_UNNECESSARY;
> >
> > +	if (!(skb->tstamp.tv64))
> > +		__net_timestamp(skb);
> > +
> >   	netif_rx_ni(skb);
> >   }
> >
> > diff --git a/net/can/af_can.c b/net/can/af_can.c
> > index 32d710e..689c818 100644
> > --- a/net/can/af_can.c
> > +++ b/net/can/af_can.c
> > @@ -310,8 +310,12 @@ int can_send(struct sk_buff *skb, int loop)
> >   		return err;
> >   	}
> >
> > -	if (newskb)
> > +	if (newskb) {
> > +		if (!(newskb->tstamp.tv64))
> > +			__net_timestamp(newskb);
> > +
> >   		netif_rx_ni(newskb);
> > +	}
> >
> >   	/* update statistics */
> >   	can_stats.tx_frames++;
> > --
> > 1.9.1
> >
>