releases/2.6.36.2/kfifo-disable-__kfifo_must_check_helper.patch

   1 From 52c5171214ff3327961d0ce0db7e8d2ce55004fd Mon Sep 17 00:00:00 2001
   2 From: Andrew Morton <akpm@linux-foundation.org>
   3 Date: Tue, 26 Oct 2010 14:21:19 -0700
   4 Subject: kfifo: disable __kfifo_must_check_helper()
   5
   6 From: Andrew Morton <akpm@linux-foundation.org>
   7
   8 commit 52c5171214ff3327961d0ce0db7e8d2ce55004fd upstream.
   9
  10 This helper is wrong: it coerces signed values into unsigned ones, so code
  11 such as
  12
  13         if (kfifo_alloc(...) < 0) {
  14                 error
  15         }
  16
  17 will fail to detect the error.
  18
  19 So let's disable __kfifo_must_check_helper() for 2.6.36.
  20
  21 Cc: Randy Dunlap <randy.dunlap@oracle.com>
  22 Cc: Stefani Seibold <stefani@seibold.net>
  23 Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
  24 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
  25 Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
  26
  27 ---
  28  include/linux/kfifo.h |    7 ++-----
  29  1 file changed, 2 insertions(+), 5 deletions(-)
  30
  31 --- a/include/linux/kfifo.h
  32 +++ b/include/linux/kfifo.h
  33 @@ -171,11 +171,8 @@ struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PT
  34         }
  35
  36
  37 -static inline unsigned int __must_check
  38 -__kfifo_must_check_helper(unsigned int val)
  39 -{
  40 -       return val;
  41 -}
  42 +/* __kfifo_must_check_helper() is temporarily disabled because it was faulty */
  43 +#define __kfifo_must_check_helper(x) (x)
  44
  45  /**
  46   * kfifo_initialized - Check if the fifo is initialized