ecore_drm2: Fix use after free

In trying to clean up some code and fix a hypothetical buffer leak, I added
a use after free error that can break rendering on the drm and gl_drm
evas engines.

Coverity did the heavy lifting for me on this one.

Fix Coverity CID 1375047
Fix T5484

diff --git a/src/lib/ecore_drm2/ecore_drm2_fb.c b/src/lib/ecore_drm2/ecore_drm2_fb.c
index 8ef2d82..114280b 100644 (file)
--- a/src/lib/ecore_drm2/ecore_drm2_fb.c
+++ b/src/lib/ecore_drm2/ecore_drm2_fb.c
@@ -553,7 +553,8 @@ ecore_drm2_fb_flip(Ecore_Drm2_Fb *fb, Ecore_Drm2_Output *output)
    /* So we can generate a tick by flipping to the current fb */
    if (!fb) fb = output->current.fb;
 
-   if (output->next.fb) _release_buffer(output, &output->next);
+   if (output->next.fb && fb != output->next.fb)
+     _release_buffer(output, &output->next);
 
    /* If we don't have an fb to set by now, BAIL! */
    if (!fb) return -1;