glib-2.0: Backport GMainContext fixes

Backport fixes introduced in 2.63.6 for memory leaks and memory corruption in
GMainContext

Upstream merge: https://gitlab.gnome.org/GNOME/glib/-/merge_requests/1353

Fixes SIGSEGV in GStreamer:

    Thread 2 "multihandlesink" received signal SIGSEGV, Segmentation fault.
    [Switching to Thread 0x7ffff6bb9700 (LWP 18045)]
    0x00007ffff7d65992 in g_source_unref_internal (source=0x7ffff00047d0, context=0x55555561c800, have_lock=1) at ../../../../../../../repo/workspace/sources/glib-2.0/glib/gmain.c:2146
    2146    ../../../../../../../repo/workspace/sources/glib-2.0/glib/gmain.c: No such file or directory.
    (gdb) bt
    #0  0x00007ffff7d65992 in g_source_unref_internal (source=0x7ffff00047d0, context=0x55555561c800, have_lock=1) at ../../../../../../../repo/workspace/sources/glib-2.0/glib/gmain.c:2146
    #1  0x00007ffff7d65bb6 in g_source_iter_next (iter=iter@entry=0x7ffff6bb8db0, source=source@entry=0x7ffff6bb8da8) at ../../../../../../../repo/workspace/sources/glib-2.0/glib/gmain.c:980
    #2  0x00007ffff7d67ef3 in g_main_context_prepare (context=context@entry=0x55555561c800, priority=priority@entry=0x7ffff6bb8e30) at ../../../../../../../repo/workspace/sources/glib-2.0/glib/gmain.c:944
    #3  0x00007ffff7d6896b in g_main_context_iterate (context=context@entry=0x55555561c800, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../../../../../../../repo/workspace/sources/glib-2.0/glib/gmain.c:3900
    #4  0x00007ffff7d68b4c in g_main_context_iteration (context=0x55555561c800, may_block=may_block@entry=1) at ../../../../../../../repo/workspace/sources/glib-2.0/glib/gmain.c:3981
    #5  0x00007ffff6be4482 in gst_multi_socket_sink_thread (mhsink=0x555555679ab0 [GstMultiSocketSink]) at ../../../gst-plugins-base-1.14.4/gst/tcp/gstmultisocketsink.c:1164
    #6  0x00007ffff7d8fb35 in g_thread_proxy (data=0x55555565c770) at ../../../../../../../repo/workspace/sources/glib-2.0/glib/gthread.c:784
    #7  0x00007ffff7841ebd in start_thread (arg=<optimized out>) at pthread_create.c:486
    #8  0x00007ffff7aa12bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
    #8  0x00007ffff7aa12bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

(From OE-Core rev: 62eb45e6455df99b0c8b61bfb90858bb656bd724)

Signed-off-by: Daniel Gomez <daniel@qtec.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 43 insertions, 0 deletions

diff --git a/meta/recipes-core/glib-2.0/glib-2.0/0011-GMainContext-Fix-GSource-iterator-if-iteration-can-m.patch b/meta/recipes-core/glib-2.0/glib-2.0/0011-GMainContext-Fix-GSource-iterator-if-iteration-can-m.patch
new file mode 100644
index 0000000000..37b77d567c
--- /dev/null
+++ b/meta/recipes-core/glib-2.0/glib-2.0/0011-GMainContext-Fix-GSource-iterator-if-iteration-can-m.patch
@@ -0,0 +1,43 @@
+From ef2be42998e3fc10299055a5a01f7c791538174c Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= <sebastian@centricular.com>
+Date: Mon, 3 Feb 2020 15:38:28 +0200
+Subject: [PATCH] GMainContext - Fix GSource iterator if iteration can modify
+ the list
+
+We first have to ref the next source and then unref the previous one.
+This might be the last reference to the previous source, and freeing the
+previous source might unref and free the next one which would then leave
+use with a dangling pointer here.
+
+Fixes https://gitlab.gnome.org/GNOME/glib/issues/2031
+
+Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/glib/-/commit/b06c48de7554607ff3fb58d6c0510cfa5088e909]
+
+---
+ glib/gmain.c | 8 ++++++--
+ 1 file changed, 6 insertions(+), 2 deletions(-)
+
+diff --git a/glib/gmain.c b/glib/gmain.c
+index af979c8..a9a287d 100644
+--- a/glib/gmain.c
++++ b/glib/gmain.c
+@@ -969,13 +969,17 @@ g_source_iter_next (GSourceIter *iter, GSource **source)
+    * GSourceList to be removed from source_lists (if iter->source is
+    * the only source in its list, and it is destroyed), so we have to
+    * keep it reffed until after we advance iter->current_list, above.
++   *
++   * Also we first have to ref the next source before unreffing the
++   * previous one as unreffing the previous source can potentially
++   * free the next one.
+    */
++  if (next_source && iter->may_modify)
++    g_source_ref (next_source);
+
+   if (iter->source && iter->may_modify)
+     g_source_unref_internal (iter->source, iter->context, TRUE);
+   iter->source = next_source;
+-  if (iter->source && iter->may_modify)
+-    g_source_ref (iter->source);
+
+   *source = iter->source;
+   return *source != NULL;