[NET]: Add skb->truesize assertion checking.

Add some sanity checking.  truesize should be at least sizeof(struct
sk_buff) plus the current packet length.  If not, then truesize is
seriously mangled and deserves a kernel log message.

Currently we'll do the check for release of stream socket buffers.

But we can add checks to more spots over time.

Incorporating ideas from Herbert Xu.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/net/core/stream.c b/net/core/stream.c
index 35e25259fd95..e9489696f694 100644
--- a/net/core/stream.c
+++ b/net/core/stream.c
@@ -176,6 +176,7 @@ void sk_stream_rfree(struct sk_buff *skb)
 {
         struct sock *sk = skb->sk;
 
+        skb_truesize_check(skb);
         atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
         sk->sk_forward_alloc += skb->truesize;
 }