[PATCH 1/1] vkd3d-shader/dxbc: Validate and skip the signature section header size.

[Conor McCarthy]

From: Conor McCarthy

Silences a very common warning.
---
 libs/vkd3d-shader/dxbc.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/libs/vkd3d-shader/dxbc.c b/libs/vkd3d-shader/dxbc.c
index d8eef8a5..73a25ae7 100644
--- a/libs/vkd3d-shader/dxbc.c
+++ b/libs/vkd3d-shader/dxbc.c
@@ -1921,9 +1921,9 @@ static int shader_parse_signature(const struct vkd3d_shader_dxbc_section_desc *s
     bool has_stream_index, has_min_precision;
     struct vkd3d_shader_signature_element *e;
     const char *data = section->data.code;
+    uint32_t count, header_size;
     const char *ptr = data;
     unsigned int i;
-    uint32_t count;

if (!require_space(0, 2, sizeof(uint32_t), section->data.size))
     {
@@ -1934,7 +1934,20 @@ static int shader_parse_signature(const struct vkd3d_shader_dxbc_section_desc *s
     read_dword(&ptr, &count);
     TRACE("%u elements.\n", count);

-    skip_dword_unknown(&ptr, 1); /* It seems to always be 0x00000008. */
+    read_dword(&ptr, &header_size);
+    if (header_size & (sizeof(uint32_t) - 1))
+    {
+        WARN("Header size %#x is not 32-bit aligned.\n", header_size);
+        return VKD3D_ERROR_INVALID_ARGUMENT;
+    }
+    header_size /= sizeof(uint32_t);
+    if (header_size < 2)
+    {
+        WARN("Invalid header size %u.\n", header_size);
+        header_size = 2;
+    }
+    for (header_size -= 2; header_size; --header_size)
+        skip_dword_unknown(&ptr, 1);

if (!require_space(ptr - data, count, 6 * sizeof(uint32_t), section->data.size))
     {