From: Marek Lindner Date: Mon, 22 Nov 2010 11:34:49 +0000 (+0100) Subject: Staging: batman-adv: ensure that eth_type_trans gets linear memory X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=b6faaae1a15a352d68b3e3cd8b840e56709820bf;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git Staging: batman-adv: ensure that eth_type_trans gets linear memory eth_type_trans tries to pull data with the length of the ethernet header from the skb. We only ensured that enough data for the first ethernet header and the batman header is available in non-paged memory of the skb and not for the ethernet after the batman header. eth_type_trans would fail sometimes with drivers which don't ensure that all there data is perfectly linearised. The failure was noticed through a kernel bug Oops generated by the skb_pull inside eth_type_trans. Reported-by: Rafal Lesniak Signed-off-by: Marek Lindner Signed-off-by: Sven Eckelmann Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/batman-adv/soft-interface.c b/drivers/staging/batman-adv/soft-interface.c index 3904db9ce7b1..0e996181daf7 100644 --- a/drivers/staging/batman-adv/soft-interface.c +++ b/drivers/staging/batman-adv/soft-interface.c @@ -194,14 +194,15 @@ void interface_rx(struct net_device *soft_iface, struct bat_priv *priv = netdev_priv(soft_iface); /* check if enough space is available for pulling, and pull */ - if (!pskb_may_pull(skb, hdr_size)) { - kfree_skb(skb); - return; - } + if (!pskb_may_pull(skb, hdr_size)) + goto dropped; + skb_pull_rcsum(skb, hdr_size); /* skb_set_mac_header(skb, -sizeof(struct ethhdr));*/ /* skb->dev & skb->pkt_type are set here */ + if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) + goto dropped; skb->protocol = eth_type_trans(skb, soft_iface); /* should not be neccesary anymore as we use skb_pull_rcsum() @@ -216,6 +217,11 @@ void interface_rx(struct net_device *soft_iface, soft_iface->last_rx = jiffies; netif_rx(skb); + return; + +dropped: + kfree_skb(skb); + return; } #ifdef HAVE_NET_DEVICE_OPS