Fix CVE-2019-19126:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-19126
https://sourceware.org/bugzilla/show_bug.cgi?id=25204

Taken from upstream:
https://sourceware.org/git/?p=glibc.git;a=commit;h=37c90e117310728a4ad1eb998c0bbe7d79c4a398

diff --git a/sysdeps/unix/sysv/linux/x86_64/64/dl-librecon.h b/sysdeps/unix/sysv/linux/x86_64/64/dl-librecon.h
index 975cbe2..df2cdfd 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/dl-librecon.h
+++ b/sysdeps/unix/sysv/linux/x86_64/64/dl-librecon.h
@@ -31,7 +31,8 @@
    environment variable, LD_PREFER_MAP_32BIT_EXEC.  */
 #define EXTRA_LD_ENVVARS \
   case 21:								  \
-    if (memcmp (envline, "PREFER_MAP_32BIT_EXEC", 21) == 0)		  \
+    if (!__libc_enable_secure						  \
+	&& memcmp (envline, "PREFER_MAP_32BIT_EXEC", 21) == 0)		  \
       GLRO(dl_x86_cpu_features).feature[index_arch_Prefer_MAP_32BIT_EXEC] \
 	|= bit_arch_Prefer_MAP_32BIT_EXEC;				  \
     break;
class='sub'>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
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<tr><td><span title='2021-08-30 14:09:32 -0400'>2021-08-30</span></td><td><a href='/guix/commit/gnu/build/jami-service.scm?id=a3bfe953d2e5f067b268c381437a807e1437c85a'>build/jami-service: Fix range ends in account-fingerprint-rx.</a><span class='msg-avail'>...<span class='msg-tooltip'>This broke compilation of Guix with guile@3.0.2 with:

  In procedure make-regexp: Invalid range end

The fix is to replace [0-9A-f] with [0-9A-Fa-f].

* gnu/build/jami-service.scm (account-fingerprint-rx): Correct regexp.

Signed-off-by: Maxim Cournoyer &lt;maxim.cournoyer@gmail.com&gt;
</span></span></td><td>Maxime Devos</td></tr>
<tr><td><span title='2021-08-02 17:23:30 -0400'>2021-08-02</span></td><td><a href='/guix/commit/gnu/build/jami-service.scm?id=10f554700c417b84c22c56fdd007567a52c45d75'>Reinstate "services: Add a service for Jami."</a><span class='msg-avail'>...<span class='msg-tooltip'>This reverts commit 4673f817938d9d2b1b40a072ab2e0c44a32ccc97, which reverted
commit 69dcc24c9f0cdfea674eb690e7755d26a25ced2b with the fix detailed below.

Thanks to Christopher Baines for reporting the failure and proposing a fix.

* guix/self.scm (compiled-guix) [*system-test-modules*]: Add the test data
files via the 'extra-files' argument.
* gnu/local.mk (dist_patch_DATA): Move the tests/data/jami-dummy-account.dat
file to...
* gnu/local.mk (MODULES_NOT_COMPILED): ... here.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2021-08-02 15:48:59 -0400'>2021-08-02</span></td><td><a href='/guix/commit/gnu/build/jami-service.scm?id=4673f817938d9d2b1b40a072ab2e0c44a32ccc97'>Revert "services: Add a service for Jami."</a><span class='msg-avail'>...<span class='msg-tooltip'>This reverts commit 69dcc24c9f0cdfea674eb690e7755d26a25ced2b.  It broke 'guix
pull'.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2021-08-02 15:15:02 -0400'>2021-08-02</span></td><td><a href='/guix/commit/gnu/build/jami-service.scm?id=69dcc24c9f0cdfea674eb690e7755d26a25ced2b'>services: Add a service for Jami.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/telephony.scm (string-or-computed-file?)
(string-list?, account-fingerprint-list?): New procedures.
(maybe-string-list, maybe-account-fingerprint-list)
(maybe-boolean, maybe-string, jami-account-list): New configuration field
types.
(serialize-string-list, serialize-boolean, serialize-string)
(jami-account, jami-account-&gt;alist, jami-configuration)
(jami-account-list?, jami-account-list-maybe): New procedures.
(%jami-accounts): New variable.
(jami-configuration-&gt;command-line-arguments): New procedure.
(jami-dbus-session-activation, jami-shepherd-services): New procedures.
(jami-service-type): New variable.
* gnu/build/jami-service.scm: New file.
* gnu/tests/data/jami-dummy-account.dat: Likewise.
* gnu/tests/telephony.scm: Likewise.
* gnu/local.mk (GNU_SYSTEM_MODULES): Register them.
* Makefile.am (SCM_TESTS): Register the test file.
(dist_patch_DATA): Register the new data file.
* doc/guix.texi (Telephony Services): Document it.
</span></span></td><td>Maxim Cournoyer</td></tr>