net: Kill skb_truesize_check(), it only catches false-positives.

A long time ago we had bugs, primarily in TCP, where we would modify
skb->truesize (for TSO queue collapsing) in ways which would corrupt
the socket memory accounting.

skb_truesize_check() was added in order to try and catch this error
more systematically.

However this debugging check has morphed into a Frankenstein of sorts
and these days it does nothing other than catch false-positives.

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

2 files changed, 0 insertions, 10 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index cf2cb50f77d1..9dcf956ad18a 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -416,15 +416,6 @@ extern void	      skb_over_panic(struct sk_buff *skb, int len,
                                      void *here);
 extern void           skb_under_panic(struct sk_buff *skb, int len,
                                       void *here);
-extern void           skb_truesize_bug(struct sk_buff *skb);
-
-static inline void skb_truesize_check(struct sk_buff *skb)
-{
-        int len = sizeof(struct sk_buff) + skb->len;
-
-        if (unlikely((int)skb->truesize < len))
-                skb_truesize_bug(skb);
-}
 
 extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
                         int getfrag(void *from, char *to, int offset,
diff --git a/include/net/sock.h b/include/net/sock.h
index ce3b5b622683..eefeeaf7fc46 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -860,7 +860,6 @@ static inline void sk_mem_uncharge(struct sock *sk, int size)
 
 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
 {
-        skb_truesize_check(skb);
         sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
         sk->sk_wmem_queued -= skb->truesize;
         sk_mem_uncharge(sk, skb->truesize);