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://rtime.felk.cvut.cz/gitweb/lisovros/linux_canprio.git/commitdiff_plain/fc359f622b4ffd5e61d317bde1544bb48b6cd6d4 Staging: batman-adv: ensure that eth_type_trans gets linear memory commit b6faaae1a15a352d68b3e3cd8b840e56709820bf upstream. 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 2ea97de435c..876be5a2913 100644 --- a/drivers/staging/batman-adv/soft-interface.c +++ b/drivers/staging/batman-adv/soft-interface.c @@ -246,6 +246,10 @@ void interface_rx(struct sk_buff *skb, int hdr_size) skb_pull_rcsum(skb, hdr_size); /* skb_set_mac_header(skb, -sizeof(struct ethhdr));*/ + if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) { + kfree_skb(skb); + return; + } skb->dev = dev; skb->protocol = eth_type_trans(skb, dev);