cirros-testvm/src-cirros/buildroot-2015.05/package/uclibc/0.9.33.2/0016-nptl-sh-fix-race-condition-in-lll_wait_tid.patch

   1 From ffd9e147b120e9c2bf30ba4861860f1bc59362c5 Mon Sep 17 00:00:00 2001
   2 From: Stas Sergeev <stsp@users.sourceforge.net>
   3 Date: Thu, 14 Jun 2012 01:00:02 +0200
   4 Subject: [PATCH] nptl: sh: fix race condition in lll_wait_tid
   5
   6 Make a local copy of the tid value to avoid a race condition,
   7 as the value could have been changed to 0, thus using a pointer
   8 it would have been passed to the lll_futex_wait modified.
   9
  10 Signed-off-by: Stas Sergeev <stsp@users.sourceforge.net>
  11 Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
  12 (cherry picked from commit 0dcc13bf7a61b1d0708e5dd103d5515e0ffec79a)
  13
  14 Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
  15 ---
  16  libpthread/nptl/sysdeps/unix/sysv/linux/sh/lowlevellock.h |    6 +++---
  17  1 file changed, 3 insertions(+), 3 deletions(-)
  18
  19 diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/sh/lowlevellock.h b/libpthread/nptl/sysdeps/unix/sysv/linux/sh/lowlevellock.h
  20 index d10cd61..b83d863 100644
  21 --- a/libpthread/nptl/sysdeps/unix/sysv/linux/sh/lowlevellock.h
  22 +++ b/libpthread/nptl/sysdeps/unix/sysv/linux/sh/lowlevellock.h
  23 @@ -396,9 +396,9 @@ extern int __lll_unlock_wake (int *__futex, int private) attribute_hidden;
  24
  25  #define lll_wait_tid(tid) \
  26    do {                                                                       \
  27 -    __typeof (tid) *__tid = &(tid);                                          \
  28 -    while (*__tid != 0)                                                              \
  29 -      lll_futex_wait (__tid, *__tid, LLL_SHARED);                            \
  30 +    __typeof (tid) __tid;                                                    \
  31 +    while ((__tid = (tid)) != 0)                                                     \
  32 +      lll_futex_wait (&(tid), __tid, LLL_SHARED);                            \
  33    } while (0)
  34
  35  extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
  36 --
  37 1.7.10.4
  38