| Message ID | 1407253479-30076-1-git-send-email-marc.zyngier@arm.com |
|---|---|
| State | New |
| Headers | show |
On Tue, Aug 05, 2014 at 04:44:39PM +0100, Marc Zyngier wrote: > Upon reception of a new frame, the emac driver checks for a number > of error conditions, and flag the packet as "bad" if any of these > are present. It then allocates a skb unconditionally, but only uses > it if the packet is "good". On the error path, the skb is just forgotten, > and the system leaks memory. > > The piece of junk I have on my desk seems to encounter such error > frequently enough so that the box goes OOM after a couple of days, > which makes me grumpy. > > Fix this by moving the allocation on the "good_packet" path (and > convert it to netdev_alloc_skb while we're at it). > > Tested on a random Allwinner A20 board. > > Cc: Stefan Roese <sr@denx.de> > Cc: Maxime Ripard <maxime.ripard@free-electrons.com> > Cc: <stable@vger.kernel.org> # 3.11+ > Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Thanks! Maxime
diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c index d81e716..29b9f08 100644 --- a/drivers/net/ethernet/allwinner/sun4i-emac.c +++ b/drivers/net/ethernet/allwinner/sun4i-emac.c @@ -633,8 +633,10 @@ static void emac_rx(struct net_device *dev) } /* Move data from EMAC */ - skb = dev_alloc_skb(rxlen + 4); - if (good_packet && skb) { + if (good_packet) { + skb = netdev_alloc_skb(dev, rxlen + 4); + if (!skb) + continue; skb_reserve(skb, 2); rdptr = (u8 *) skb_put(skb, rxlen - 4);
Upon reception of a new frame, the emac driver checks for a number of error conditions, and flag the packet as "bad" if any of these are present. It then allocates a skb unconditionally, but only uses it if the packet is "good". On the error path, the skb is just forgotten, and the system leaks memory. The piece of junk I have on my desk seems to encounter such error frequently enough so that the box goes OOM after a couple of days, which makes me grumpy. Fix this by moving the allocation on the "good_packet" path (and convert it to netdev_alloc_skb while we're at it). Tested on a random Allwinner A20 board. Cc: Stefan Roese <sr@denx.de> Cc: Maxime Ripard <maxime.ripard@free-electrons.com> Cc: <stable@vger.kernel.org> # 3.11+ Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> --- drivers/net/ethernet/allwinner/sun4i-emac.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)