glx/drisw: return false if shmid == -1

[mesa.git] / src / glx / drisw_glx.c

diff --git a/src/glx/drisw_glx.c b/src/glx/drisw_glx.c
index 6e37f0274b04e0f2be84fc2ef715ce6f635fff75..dfa3218d759ecf61d4fab2cc970545e77f64cd85 100644 (file)
--- a/src/glx/drisw_glx.c
+++ b/src/glx/drisw_glx.c
@@ -303,6 +303,9 @@ swrastGetImageShm2(__DRIdrawable * read,
       if (!XCreateDrawable(prp, shmid, dpy))
          return GL_FALSE;
    }
+
+   if (prp->shminfo.shmid == -1)
+      return GL_FALSE;
    readable = pread->xDrawable;
 
    ximage = prp->ximage;