Revert "udp: remove redundant variable"
This reverts commit 81d54ec8 . If we take the "try_again" goto, due to a checksum error, the 'len' has already been truncated. So we won't compute the same values as the original code did. Reported-by: paul bilke <email@example.com> Signed-off-by: David S. Miller <firstname.lastname@example.org>