gnu/packages/patches/python-2.7-getentropy-on-old-kernels.patch

   1 This patch resolves a compatibility issue when compiled against glibc
   2 2.25
   3 and run runder kernels < 3.17:
   4
   5 https://bugzilla.redhat.com/show_bug.cgi?id=1410175
   6
   7 Upstream bug URLs:
   8
   9 https://bugs.python.org/issue29157
  10 https://bugs.python.org/issue29188
  11
  12 Patch adapted from upstream source repository:
  13
  14 https://github.com/python/cpython/commit/01bdbad3e951014c58581635b94b22868537901c
  15
  16 From 01bdbad3e951014c58581635b94b22868537901c Mon Sep 17 00:00:00 2001
  17 From: Victor Stinner <victor.stinner@gmail.com>
  18 Date: Mon, 9 Jan 2017 11:10:41 +0100
  19 Subject: [PATCH] Don't use getentropy() on Linux
  20
  21 Issue #29188: Support glibc 2.24 on Linux: don't use getentropy() function but
  22 read from /dev/urandom to get random bytes, for example in os.urandom().  On
  23 Linux, getentropy() is implemented which getrandom() is blocking mode, whereas
  24 os.urandom() should not block.
  25 ---
  26  Misc/NEWS       |  5 +++++
  27  Python/random.c | 11 +++++++++--
  28  2 files changed, 14 insertions(+), 2 deletions(-)
  29
  30 diff --git a/Python/random.c b/Python/random.c
  31 index 57c41ffcd6..000cb36938 100644
  32 --- a/Python/random.c
  33 +++ b/Python/random.c
  34 @@ -97,8 +97,15 @@ win32_urandom(unsigned char *buffer, Py_ssize_t size, int raise)
  35  }
  36
  37  /* Issue #25003: Don't use getentropy() on Solaris (available since
  38 - * Solaris 11.3), it is blocking whereas os.urandom() should not block. */
  39 -#elif defined(HAVE_GETENTROPY) && !defined(sun)
  40 +   Solaris 11.3), it is blocking whereas os.urandom() should not block.
  41 +
  42 +   Issue #29188: Don't use getentropy() on Linux since the glibc 2.24
  43 +   implements it with the getrandom() syscall which can fail with ENOSYS,
  44 +   and this error is not supported in py_getentropy() and getrandom() is called
  45 +   with flags=0 which blocks until system urandom is initialized, which is not
  46 +   the desired behaviour to seed the Python hash secret nor for os.urandom():
  47 +   see the PEP 524 which was only implemented in Python 3.6. */
  48 +#elif defined(HAVE_GETENTROPY) && !defined(sun) && !defined(linux)
  49  #define PY_GETENTROPY 1
  50
  51  /* Fill buffer with size pseudo-random bytes generated by getentropy().
  52 --
  53 2.12.0
  54