From 2670cc699a66c4cf268cb3e3f6dfc325ec14f224 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 5 Aug 2014 16:44:39 +0100 Subject: [PATCH] net: sun4i-emac: fix memory leak on bad packet 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 Cc: Maxime Ripard Cc: # 3.11+ Signed-off-by: Marc Zyngier Acked-by: Maxime Ripard Signed-off-by: David S. Miller --- drivers/net/ethernet/allwinner/sun4i-emac.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c index d81e7167a8b5..29b9f082475d 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); -- 2.34.1