[ 48/56] aoe: reserve enough headroom on skbs

Greg Kroah-Hartman
2013-04-02T22:51:00Z

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit 91c5746425aed8f7188a351f1224a26aa232e4b3 ]

Some network drivers use a non default hard_header_len

Transmitted skb should take into account dev->hard_header_len, or risk
crashes or expensive reallocations.

In the case of aoe, lets reserve MAX_HEADER bytes.

David reported a crash in defxx driver, solved by this patch.

Reported-by: David Oostdyk <daveo@ll.mit.edu>
Tested-by: David Oostdyk <daveo@ll.mit.edu>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ed Cashin <ecashin@coraid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/block/aoe/aoecmd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -30,8 +30,9 @@ new_skb(ulong len)
{
struct sk_buff *skb;

- skb = alloc_skb(len, GFP_ATOMIC);
+ skb = alloc_skb(len + MAX_HEADER, GFP_ATOMIC);
if (skb) {
+ skb_reserve(skb, MAX_HEADER);
skb_reset_mac_header(skb);
skb_reset_network_header(skb);
skb->protocol = __constant_htons(ETH_P_AOE);