net: avoid sk_forward_alloc overflows

[pandora-kernel.git] / include / net / sock.h

diff --git a/include/net/sock.h b/include/net/sock.h
index b0da43d..ba673a1 100644 (file)
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1023,6 +1023,16 @@ static inline void sk_mem_uncharge(struct sock *sk, int size)
        if (!sk_has_account(sk))
                return;
        sk->sk_forward_alloc += size;
+
+       /* Avoid a possible overflow.
+        * TCP send queues can make this happen, if sk_mem_reclaim()
+        * is not called and more than 2 GBytes are released at once.
+        *
+        * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
+        * no need to hold that much forward allocation anyway.
+        */
+       if (unlikely(sk->sk_forward_alloc >= 1 << 21))
+               __sk_mem_reclaim(sk, 1 << 20);
 }
 
 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)