patches/kernel/0065-bitops-Add-clear-set_bit32-to-linux-bitops.h.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Andi Kleen <ak@linux.intel.com>
   3 Date: Fri, 13 Oct 2017 14:56:41 -0700
   4 Subject: [PATCH] bitops: Add clear/set_bit32() to linux/bitops.h
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 CVE-2017-5754
  10
  11 Add two simple wrappers around set_bit/clear_bit() that accept
  12 the common case of an u32 array. This avoids writing
  13 casts in all callers.
  14
  15 Signed-off-by: Andi Kleen <ak@linux.intel.com>
  16 Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
  17 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  18 Cc: Peter Zijlstra <peterz@infradead.org>
  19 Link: http://lkml.kernel.org/r/20171013215645.23166-2-andi@firstfloor.org
  20 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  21 (cherry picked from commit cbe96375025e14fc76f9ed42ee5225120d7210f8)
  22 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  23 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  24 (cherry picked from commit 06d31c11519ca0e8f9b7cab857f442ef44dfc1b2)
  25 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  26 ---
  27  include/linux/bitops.h | 26 ++++++++++++++++++++++++++
  28  1 file changed, 26 insertions(+)
  29
  30 diff --git a/include/linux/bitops.h b/include/linux/bitops.h
  31 index a83c822c35c2..eb257a96db6d 100644
  32 --- a/include/linux/bitops.h
  33 +++ b/include/linux/bitops.h
  34 @@ -226,6 +226,32 @@ static inline unsigned long __ffs64(u64 word)
  35         return __ffs((unsigned long)word);
  36  }
  37
  38 +/*
  39 + * clear_bit32 - Clear a bit in memory for u32 array
  40 + * @nr: Bit to clear
  41 + * @addr: u32 * address of bitmap
  42 + *
  43 + * Same as clear_bit, but avoids needing casts for u32 arrays.
  44 + */
  45 +
  46 +static __always_inline void clear_bit32(long nr, volatile u32 *addr)
  47 +{
  48 +       clear_bit(nr, (volatile unsigned long *)addr);
  49 +}
  50 +
  51 +/*
  52 + * set_bit32 - Set a bit in memory for u32 array
  53 + * @nr: Bit to clear
  54 + * @addr: u32 * address of bitmap
  55 + *
  56 + * Same as set_bit, but avoids needing casts for u32 arrays.
  57 + */
  58 +
  59 +static __always_inline void set_bit32(long nr, volatile u32 *addr)
  60 +{
  61 +       set_bit(nr, (volatile unsigned long *)addr);
  62 +}
  63 +
  64  #ifdef __KERNEL__
  65
  66  #ifndef set_mask_bits
  67 --
  68 2.14.2
  69