[Mesa-dev] [PATCH 10/13] mesa/main: Check context pointer in _mesa_error before using it

[Juha-Pekka Heikkila]

I guess this should not really be able to segfault but still it
seems to be able to during context creation.

Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila at gmail.com>
---
 src/mesa/main/errors.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/src/mesa/main/errors.c b/src/mesa/main/errors.c
index 7d622bb..705dea9 100644
--- a/src/mesa/main/errors.c
+++ b/src/mesa/main/errors.c
@@ -1438,18 +1438,23 @@ _mesa_error( struct gl_context *ctx, GLenum error, const char *fmtString, ... )
 
    do_output = should_output(ctx, error, fmtString);
 
-   mtx_lock(&ctx->DebugMutex);
-   if (ctx->Debug) {
-      do_log = debug_is_message_enabled(ctx->Debug,
-                                        MESA_DEBUG_SOURCE_API,
-                                        MESA_DEBUG_TYPE_ERROR,
-                                        error_msg_id,
-                                        MESA_DEBUG_SEVERITY_HIGH);
+   if (ctx) {
+      mtx_lock(&ctx->DebugMutex);
+      if (ctx->Debug) {
+         do_log = debug_is_message_enabled(ctx->Debug,
+                                           MESA_DEBUG_SOURCE_API,
+                                           MESA_DEBUG_TYPE_ERROR,
+                                           error_msg_id,
+                                           MESA_DEBUG_SEVERITY_HIGH);
+      }
+      else {
+         do_log = GL_FALSE;
+      }
+      mtx_unlock(&ctx->DebugMutex);
    }
    else {
       do_log = GL_FALSE;
    }
-   mtx_unlock(&ctx->DebugMutex);
 
    if (do_output || do_log) {
       char s[MAX_DEBUG_MESSAGE_LENGTH], s2[MAX_DEBUG_MESSAGE_LENGTH];
@@ -1482,14 +1487,15 @@ _mesa_error( struct gl_context *ctx, GLenum error, const char *fmtString, ... )
       }
 
       /* Log the error via ARB_debug_output if needed.*/
-      if (do_log) {
+      if (ctx && do_log) {
          log_msg(ctx, MESA_DEBUG_SOURCE_API, MESA_DEBUG_TYPE_ERROR,
                  error_msg_id, MESA_DEBUG_SEVERITY_HIGH, len, s2);
       }
    }
 
    /* Set the GL context error state for glGetError. */
-   _mesa_record_error(ctx, error);
+   if (ctx)
+      _mesa_record_error(ctx, error);
 }
 
 void
-- 
1.8.5.1