From dd67c079a0180aadba58c55dd6d3cd97c4e1115d Mon Sep 17 00:00:00 2001
From: Adam Jackson <ajax@redhat.com>
Date: Thu, 22 Jul 2021 16:28:31 -0400
Subject: [PATCH] dri: Validate more of the context version in
 validate_context_version

There's two kinds of "bad version" you might encounter here, either the
combination does not name a defined version (like 1.7) or it names
something the driver can't do (like asking r300 to do 4.0). EGL does not
distinguish these cases, but GLX calls them BadMatch and GLXBadFBConfig
respectively.

Since api_mask is the set of driver supported APIs, and we can only
support defined APIs, don't check it early in driCreateContextAttribs,
just let it fall out from validate_context_version.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12006>
---
 src/gallium/frontends/dri/dri_util.c | 71 +++++++++++++++-------------
 1 file changed, 38 insertions(+), 33 deletions(-)

diff --git a/src/gallium/frontends/dri/dri_util.c b/src/gallium/frontends/dri/dri_util.c
index 026fa5f8560..420477a1614 100644
--- a/src/gallium/frontends/dri/dri_util.c
+++ b/src/gallium/frontends/dri/dri_util.c
@@ -391,43 +391,53 @@ driIndexConfigAttrib(const __DRIconfig *config, int index,
     return GL_FALSE;
 }
 
-static bool
+static int
 validate_context_version(struct dri_screen *screen,
                          int mesa_api,
                          unsigned major_version,
-                         unsigned minor_version,
-                         unsigned *dri_ctx_error)
+                         unsigned minor_version)
 {
    unsigned req_version = 10 * major_version + minor_version;
    unsigned max_version = 0;
 
-   switch (mesa_api) {
-   case API_OPENGL_COMPAT:
+   if (major_version == 0 || major_version > 4)
+      return __DRI_CTX_ERROR_BAD_API;
+
+   if (mesa_api == API_OPENGL_COMPAT) {
+      if ((major_version == 4 && minor_version > 6) ||
+          (major_version == 3 && minor_version > 3) ||
+          (major_version == 2 && minor_version > 1) ||
+          (major_version == 1 && minor_version > 5))
+         return __DRI_CTX_ERROR_BAD_API;
       max_version = screen->max_gl_compat_version;
-      break;
-   case API_OPENGL_CORE:
-      max_version = screen->max_gl_core_version;
-      break;
-   case API_OPENGLES:
+   } else if (mesa_api == API_OPENGLES) {
+      if (major_version > 1 || minor_version > 1)
+         return __DRI_CTX_ERROR_BAD_API;
       max_version = screen->max_gl_es1_version;
-      break;
-   case API_OPENGLES2:
+   } else if (mesa_api == API_OPENGLES2) {
+      if ((major_version >  3) ||
+          (major_version == 3 && minor_version > 2) ||
+          (major_version == 2 && minor_version > 0) ||
+          (major_version <  2))
+         return __DRI_CTX_ERROR_BAD_API;
       max_version = screen->max_gl_es2_version;
-      break;
-   default:
-      max_version = 0;
-      break;
+   } else if (mesa_api == API_OPENGL_CORE) {
+      if ((major_version == 4 && minor_version > 6) ||
+          (major_version == 3 && minor_version > 3) ||
+          (major_version < 3))
+         return __DRI_CTX_ERROR_BAD_API;
+      max_version = screen->max_gl_core_version;
+   } else {
+      return __DRI_CTX_ERROR_BAD_API;
    }
 
-   if (max_version == 0) {
-      *dri_ctx_error = __DRI_CTX_ERROR_BAD_API;
-      return false;
-   } else if (req_version > max_version) {
-      *dri_ctx_error = __DRI_CTX_ERROR_BAD_VERSION;
-      return false;
-   }
+   if (max_version == 0)
+      return __DRI_CTX_ERROR_BAD_VERSION;
 
-   return true;
+   if (req_version > max_version)
+      return __DRI_CTX_ERROR_BAD_VERSION;
+
+   return __DRI_CTX_ERROR_SUCCESS;
 }
 
 /*****************************************************************/
@@ -457,11 +467,6 @@ driCreateContextAttribs(__DRIscreen *psp, int api,
 
     assert((num_attribs == 0) || (attribs != NULL));
 
-    if (!(screen->api_mask & (1 << api))) {
-        *error = __DRI_CTX_ERROR_BAD_API;
-        return NULL;
-    }
-
     switch (api) {
     case __DRI_API_OPENGL:
         mesa_api = API_OPENGL_COMPAT;
@@ -613,10 +618,10 @@ driCreateContextAttribs(__DRIscreen *psp, int api,
         return NULL;
     }
 
-    if (!validate_context_version(screen, mesa_api,
-                                  ctx_config.major_version,
-                                  ctx_config.minor_version,
-                                  error))
+    *error = validate_context_version(screen, mesa_api,
+                                      ctx_config.major_version,
+                                      ctx_config.minor_version);
+    if (*error != __DRI_CTX_ERROR_SUCCESS)
        return NULL;
 
     struct dri_context *ctx = dri_create_context(screen, mesa_api,