meta-lxatac-bsp: rauc: add patch to fix RAUC info / update notifications

Currently the update notifications on the LXA TAC LCD and web interface
do not work because the tacd can not get informations about the RAUC
bundle on the update server via RAUC's DBus API.

This is because the process that RAUC spawns to handle the nbd bridge
for http streaming crashes due to an unitialized pointer access.

This patch is taken from RAUC pull request 1332 [1], which fixes the issue.

[1]: rauc/rauc#1332

Signed-off-by: Leonard Göhrs <l.goehrs@pengutronix.de>

meta-lxatac-bsp/recipes-core/rauc/files/0001-src-nbd-initialize-info_headers-to-NULL.patch

@@ -0,0 +1,38 @@
+From 967d32571e226d15c345b2d8cec932a651716f4b Mon Sep 17 00:00:00 2001
+From: Enrico Jorns <ejo@pengutronix.de>
+Date: Thu, 18 Jan 2024 16:49:46 +0100
+Subject: [PATCH] src/nbd: initialize info_headers to NULL
+
+When g_variant_dict_lookup() does not find the given key, it does not
+modify the values of the arguments provided.
+
+This results in info_headers being undefined and can cause the
+rauc-nbd-server to crash, which will result in a broken request on
+client side that lets RAUC terminate hard with:
+
+(rauc:769): rauc-nbd-ERROR **: 15:40:30.553: failed to recv nbd config reply header
+
+The behavior of g_variant_dict_lookup() has also recently been clarified
+in the glib documentation:
+https://gitlab.gnome.org/GNOME/glib/-/merge_requests/3334
+
+Upstream-Status: Submitted [https://github.com/rauc/rauc/pull/1332]
+
+Signed-off-by: Enrico Jorns <ejo@pengutronix.de>
+---
+ src/nbd.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/nbd.c b/src/nbd.c
+index 41c43b3..018022e 100644
+--- a/src/nbd.c
++++ b/src/nbd.c
+@@ -562,7 +562,7 @@ static void start_configure(struct RaucNBDContext *ctx, struct RaucNBDTransfer *
+
+ 	/* only read from the client on the first try */
+ 	if (!ctx->url) {
+-		GStrv info_headers; /* array of strings such as 'Foo: bar' */
++		GStrv info_headers = NULL; /* array of strings such as 'Foo: bar' */
+
+ 		res = r_read_exact(ctx->sock, (guint8*)data, xfer->request.len, NULL);
+ 		g_assert_true(res);

meta-lxatac-bsp/recipes-core/rauc/rauc_%.bbappend

@@ -3,6 +3,7 @@ FILESEXTRAPATHS:prepend := "${THISDIR}/files:"
 RDEPENDS:${PN}:append = "bash e2fsprogs-resize2fs"
 
 SRC_URI:append = " \
+    file://0001-src-nbd-initialize-info_headers-to-NULL.patch \
     file://require-mount-srv.conf \
     file://rauc-disable-cert.sh \
     file://rauc-enable-cert.sh \