dev-qt/qtwayland: Scanner: Avoid dangling pointers in destroy_func()

See also: https://mail.kde.org/pipermail/plasma-devel/2021-January/119115.html

Package-Manager: Portage-3.0.12, Repoman-3.0.2
Signed-off-by: Andreas Sturmlechner <asturm@gentoo.org>

2 files changed, 76 insertions, 0 deletions

diff --git a/dev-qt/qtwayland/files/qtwayland-5.15.2-qtwaylandscanner-avoid-dangling-pointers.patch b/dev-qt/qtwayland/files/qtwayland-5.15.2-qtwaylandscanner-avoid-dangling-pointers.patch
new file mode 100644
index 000000000000..0799cb1a2023
--- /dev/null
+++ b/dev-qt/qtwayland/files/qtwayland-5.15.2-qtwaylandscanner-avoid-dangling-pointers.patch
@@ -0,0 +1,35 @@
+From 735164b5c2a2637a8d53a8803a2401e4ef477ff0 Mon Sep 17 00:00:00 2001
+From: Vlad Zahorodnii <vlad.zahorodnii@kde.org>
+Date: Fri, 30 Oct 2020 16:55:30 +0200
+Subject: [PATCH] Scanner: Avoid accessing dangling pointers in destroy_func()
+
+Usually, the object associated with the resource gets destroyed in the
+destroy_resource() function.
+
+Therefore, we need to double-check that the object is still alive before
+trying to reset its m_resource.
+
+Pick-to: 5.15
+Change-Id: I26408228f58919db17eb29584a1cbd4a9427d25c
+Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>
+---
+ src/qtwaylandscanner/qtwaylandscanner.cpp | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/src/qtwaylandscanner/qtwaylandscanner.cpp b/src/qtwaylandscanner/qtwaylandscanner.cpp
+index 1a1f8bf16..450ef519d 100644
+--- a/src/qtwaylandscanner/qtwaylandscanner.cpp
++++ b/src/qtwaylandscanner/qtwaylandscanner.cpp
+@@ -814,7 +814,9 @@ bool Scanner::process()
+             printf("        if (Q_LIKELY(that)) {\n");
+             printf("            that->m_resource_map.remove(resource->client(), resource);\n");
+             printf("            that->%s_destroy_resource(resource);\n", interfaceNameStripped);
+-            printf("            if (that->m_resource == resource)\n");
++            printf("\n");
++            printf("            that = resource->%s_object;\n", interfaceNameStripped);
++            printf("            if (that && that->m_resource == resource)\n");
+             printf("                that->m_resource = nullptr;\n");
+             printf("        }\n");
+             printf("        delete resource;\n");
+-- 
+2.16.3
diff --git a/dev-qt/qtwayland/qtwayland-5.15.2-r1.ebuild b/dev-qt/qtwayland/qtwayland-5.15.2-r1.ebuild
new file mode 100644
index 000000000000..ea32d4ffc9c8
--- /dev/null
+++ b/dev-qt/qtwayland/qtwayland-5.15.2-r1.ebuild
@@ -0,0 +1,41 @@
+# Copyright 1999-2021 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+inherit qt5-build
+
+DESCRIPTION="Wayland platform plugin for Qt"
+
+if [[ ${QT5_BUILD_TYPE} == release ]]; then
+	KEYWORDS="~amd64 ~arm ~arm64 ~hppa ~ppc ~ppc64 ~sparc ~x86"
+fi
+
+IUSE="vulkan X"
+
+DEPEND="
+	>=dev-libs/wayland-1.6.0
+	~dev-qt/qtcore-${PV}
+	~dev-qt/qtdeclarative-${PV}
+	~dev-qt/qtgui-${PV}[egl,libinput,vulkan=]
+	media-libs/mesa[egl]
+	>=x11-libs/libxkbcommon-0.2.0
+	vulkan? ( dev-util/vulkan-headers )
+	X? (
+		~dev-qt/qtgui-${PV}[-gles2-only]
+		x11-libs/libX11
+		x11-libs/libXcomposite
+	)
+"
+RDEPEND="${DEPEND}"
+
+PATCHES=( "${FILESDIR}"/${P}-qtwaylandscanner-avoid-dangling-pointers.patch )
+
+src_configure() {
+	local myqmakeargs=(
+		--
+		$(qt_use vulkan feature-wayland-vulkan-server-buffer)
+		$(qt_use X feature-xcomposite-egl)
+		$(qt_use X feature-xcomposite-glx)
+	)
+	qt5-build_src_configure
+}