bug#26093: [PATCH 1/2] gnu: address@hidden: Fix getentropy() calls on kernels < 3.17.

[Leo Famulari]

* gnu/packages/patches/python-2.7-getentropy-on-old-kernels.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/python.scm (python-2.7)[source]: Use it.
---
 gnu/local.mk                                       |  1 +
 .../python-2.7-getentropy-on-old-kernels.patch     | 67 ++++++++++++++++++++++
 gnu/packages/python.scm                            |  3 +-
 3 files changed, 70 insertions(+), 1 deletion(-)
 create mode 100644 
gnu/packages/patches/python-2.7-getentropy-on-old-kernels.patch

diff --git a/gnu/local.mk b/gnu/local.mk
index c74418d0d..ea2e47274 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -848,6 +848,7 @@ dist_patch_DATA =                                           
\
   %D%/packages/patches/pygpgme-disable-problematic-tests.patch  \
   %D%/packages/patches/pyqt-configure.patch                    \
   %D%/packages/patches/python-2-deterministic-build-info.patch \
+  %D%/packages/patches/python-2.7-getentropy-on-old-kernels.patch      \
   %D%/packages/patches/python-2.7-search-paths.patch           \
   %D%/packages/patches/python-2.7-site-prefixes.patch          \
   %D%/packages/patches/python-2.7-source-date-epoch.patch      \
diff --git a/gnu/packages/patches/python-2.7-getentropy-on-old-kernels.patch 
b/gnu/packages/patches/python-2.7-getentropy-on-old-kernels.patch
new file mode 100644
index 000000000..ab4afba1a
--- /dev/null
+++ b/gnu/packages/patches/python-2.7-getentropy-on-old-kernels.patch
@@ -0,0 +1,67 @@
+This patch resolves a compatibility issue when compiled against glibc
+2.25
+and run runder kernels < 3.17:
+
+https://bugzilla.redhat.com/show_bug.cgi?id=1410175
+
+Upstream bug URL: https://bugs.python.org/issue29157
+
+Patch copied from upstream source repository:
+
+https://github.com/python/cpython/commit/01bdbad3e951014c58581635b94b22868537901c
+
+From 01bdbad3e951014c58581635b94b22868537901c Mon Sep 17 00:00:00 2001
+From: Victor Stinner <address@hidden>
+Date: Mon, 9 Jan 2017 11:10:41 +0100
+Subject: [PATCH] Don't use getentropy() on Linux
+
+Issue #29188: Support glibc 2.24 on Linux: don't use getentropy() function but
+read from /dev/urandom to get random bytes, for example in os.urandom().  On
+Linux, getentropy() is implemented which getrandom() is blocking mode, whereas
+os.urandom() should not block.
+---
+ Misc/NEWS       |  5 +++++
+ Python/random.c | 11 +++++++++--
+ 2 files changed, 14 insertions(+), 2 deletions(-)
+
+#diff --git a/Misc/NEWS b/Misc/NEWS
+#index d1f7b5ebbf..fd08a7e0b8 100644
+#--- a/Misc/NEWS
+#+++ b/Misc/NEWS
+#@@ -23,6 +23,11 @@ Extension Modules
+# Library
+# -------
+# 
+#+- Issue #29188: Support glibc 2.24 on Linux: don't use getentropy() function
+#+  but read from /dev/urandom to get random bytes, for example in 
os.urandom().
+#+  On Linux, getentropy() is implemented which getrandom() is blocking mode,
+#+  whereas os.urandom() should not block.
+#+
+# - Issue #29142: In urllib, suffixes in no_proxy environment variable with
+#   leading dots could match related hostnames again (e.g. .b.c matches a.b.c).
+#   Patch by Milan Oberkirch.
+diff --git a/Python/random.c b/Python/random.c
+index 57c41ffcd6..000cb36938 100644
+--- a/Python/random.c
++++ b/Python/random.c
+@@ -97,8 +97,15 @@ win32_urandom(unsigned char *buffer, Py_ssize_t size, int 
raise)
+ }
+ 
+ /* Issue #25003: Don't use getentropy() on Solaris (available since
+- * Solaris 11.3), it is blocking whereas os.urandom() should not block. */
+-#elif defined(HAVE_GETENTROPY) && !defined(sun)
++   Solaris 11.3), it is blocking whereas os.urandom() should not block.
++
++   Issue #29188: Don't use getentropy() on Linux since the glibc 2.24
++   implements it with the getrandom() syscall which can fail with ENOSYS,
++   and this error is not supported in py_getentropy() and getrandom() is 
called
++   with flags=0 which blocks until system urandom is initialized, which is not
++   the desired behaviour to seed the Python hash secret nor for os.urandom():
++   see the PEP 524 which was only implemented in Python 3.6. */
++#elif defined(HAVE_GETENTROPY) && !defined(sun) && !defined(linux)
+ #define PY_GETENTROPY 1
+ 
+ /* Fill buffer with size pseudo-random bytes generated by getentropy().
+-- 
+2.12.0
+
diff --git a/gnu/packages/python.scm b/gnu/packages/python.scm
index 60f059445..f8e308d52 100644
--- a/gnu/packages/python.scm
+++ b/gnu/packages/python.scm
@@ -132,7 +132,8 @@
       (patches (search-patches "python-2.7-search-paths.patch"
                                "python-2-deterministic-build-info.patch"
                                "python-2.7-site-prefixes.patch"
-                               "python-2.7-source-date-epoch.patch"))
+                               "python-2.7-source-date-epoch.patch"
+                               "python-2.7-getentropy-on-old-kernels.patch"))
       (modules '((guix build utils)))
       ;; suboptimal to delete failing tests here, but if we delete them in the
       ;; arguments then we need to make sure to strip out that phase when it
-- 
2.12.0