[PATCH xserver] modesetting: Validate the atom for enum properties

[Adam Jackson]

The client could have said anything here, and if what they said doesn't
actually name an atom NameForAtom() will return NULL, and strcmp() will
be unhappy about that.

Signed-off-by: Adam Jackson <ajax at redhat.com>
---
 hw/xfree86/drivers/modesetting/drmmode_display.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/xfree86/drivers/modesetting/drmmode_display.c b/hw/xfree86/drivers/modesetting/drmmode_display.c
index aa6baae09..961b56127 100644
--- a/hw/xfree86/drivers/modesetting/drmmode_display.c
+++ b/hw/xfree86/drivers/modesetting/drmmode_display.c
@@ -1557,7 +1557,8 @@ drmmode_output_set_property(xf86OutputPtr output, Atom property,
                 value->size != 1)
                 return FALSE;
             memcpy(&atom, value->data, 4);
-            name = NameForAtom(atom);
+            if (!(name = NameForAtom(atom)))
+                return FALSE;
 
             /* search for matching name string, then set its value down */
             for (j = 0; j < p->mode_prop->count_enums; j++) {
-- 
2.13.0