[patch] net: get rid of redundant access_ok() call in checksum calculation.

[Jesper Juhl <juhl-lkml@xxxxxx>]

Hi,

in include/net/checksum.h::csum_and_copy_to_user  it would seem that the 
access_ok() call before attempting to call copy_to_user() is redundant 
since copy_to_user() calls access_ok() internally.

If that is indeed the case then please consider applying the patch below 
(if that access_ok() does make sense I'd apreciate to be told why).


Signed-off-by: Jesper Juhl <juhl-lkml@xxxxxx>

diff -up linux-2.6.10-bk9-orig/include/net/checksum.h 
linux-2.6.10-bk9/include/net/checksum.h
--- linux-2.6.10-bk9-orig/include/net/checksum.h        2004-12-24 
22:34:26.000000000 +0100
+++ linux-2.6.10-bk9/include/net/checksum.h     2005-01-07 00:27:05.000000000 
+0100
@@ -46,10 +46,9 @@ static __inline__ unsigned int csum_and_
 {
        sum = csum_partial(src, len, sum);
 
-       if (access_ok(VERIFY_WRITE, dst, len)) {
-               if (copy_to_user(dst, src, len) == 0)
-                       return sum;
-       }
+       if (copy_to_user(dst, src, len) == 0)
+               return sum;
+
        if (len)
                *err_ptr = -EFAULT;