File gstreamer-plugins-bad-CVE-2023-40474.patch of Package gstreamer-plugins-bad.31942

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File gstreamer-plugins-bad-CVE-2023-40474.patch of Package gstreamer-plugins-bad.31942

commit ce17e968e4cf900d28ca5b46f6e095febc42b4f0
Author: Sebastian Dröge <sebastian@centricular.com>
Date:   Thu Aug 10 15:45:01 2023 +0300

mxfdemux: Fix integer overflow causing out of bounds writes when handling invalid uncompressed video

Check ahead of time when parsing the track information whether
    width, height and bpp are valid and usable without overflows.

Fixes ZDI-CAN-21660, CVE-2023-40474

Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/2896

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5362>

diff -Nura gst-plugins-bad-1.2.4/gst/mxf/mxfup.c gst-plugins-bad-1.2.4_new/gst/mxf/mxfup.c
--- gst-plugins-bad-1.2.4/gst/mxf/mxfup.c	2013-09-24 21:06:21.000000000 +0800
+++ gst-plugins-bad-1.2.4_new/gst/mxf/mxfup.c	2023-11-14 23:57:05.052055669 +0800
@@ -134,6 +134,8 @@
     gpointer mapping_data, GstBuffer ** outbuf)
 {
   MXFUPMappingData *data = mapping_data;
+  gsize expected_in_stride = 0, out_stride = 0;
+  gsize expected_in_size = 0, out_size = 0;
 
   /* SMPTE 384M 7.1 */
   if (key->u[12] != 0x15 || (key->u[14] != 0x01 && key->u[14] != 0x02
@@ -155,25 +157,30 @@
     }
   }
 
-  if (gst_buffer_get_size (buffer) != data->bpp * data->width * data->height) {
+  // Checked for overflows when parsing the descriptor
+  expected_in_stride = data->bpp * data->width;
+  out_stride = GST_ROUND_UP_4 (expected_in_stride);
+  expected_in_size = expected_in_stride * data->height;
+  out_size = out_stride * data->height;
+
+  if (gst_buffer_get_size (buffer) != expected_in_size) {
     GST_ERROR ("Invalid buffer size");
+    gst_buffer_unref (buffer);
     return GST_FLOW_ERROR;
-  }
+   }
 
-  if (data->bpp != 4
-      || GST_ROUND_UP_4 (data->width * data->bpp) != data->width * data->bpp) {
+  if (data->bpp != 4 || out_stride != expected_in_stride) {
     guint y;
     GstBuffer *ret;
     GstMapInfo inmap, outmap;
     guint8 *indata, *outdata;
 
-    ret =
-        gst_buffer_new_and_alloc (GST_ROUND_UP_4 (data->width * data->bpp) *
-        data->height);
+    ret = gst_buffer_new_and_alloc (out_size);
     gst_buffer_map (buffer, &inmap, GST_MAP_READ);
     gst_buffer_map (ret, &outmap, GST_MAP_WRITE);
-    indata = inmap.data;
-    outdata = outmap.data;
+    outdata += out_stride;
+    indata += expected_in_stride;
+
 
     for (y = 0; y < data->height; y++) {
       memcpy (outdata, indata, data->width * data->bpp);
@@ -377,6 +384,36 @@
     return NULL;
   }
 
+  if (caps) {
+    MXFUPMappingData *data = *mapping_data;
+    gsize expected_in_stride = 0, out_stride = 0;
+    gsize expected_in_size = 0, out_size = 0;
+
+    // Do some checking of the parameters to see if they're valid and
+    // we can actually work with them.
+    if (data->image_start_offset > data->image_end_offset) {
+      GST_WARNING ("Invalid image start/end offset");
+      g_free (data);
+      *mapping_data = NULL;
+      gst_clear_caps (&caps);
+
+      return NULL;
+    }
+
+    if (!g_size_checked_mul (&expected_in_stride, data->bpp, data->width) ||
+        (out_stride = GST_ROUND_UP_4 (expected_in_stride)) < expected_in_stride
+        || !g_size_checked_mul (&expected_in_size, expected_in_stride,
+            data->height)
+        || !g_size_checked_mul (&out_size, out_stride, data->height)) {
+      GST_ERROR ("Invalid resolution or bit depth");
+      g_free (data);
+      *mapping_data = NULL;
+      gst_clear_caps (&caps);
+
+      return NULL;
+    }
+  }
+
   return caps;
 }

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File gstreamer-plugins-bad-CVE-2023-40474.patch of Package gstreamer-plugins-bad.31942

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