From 3e9baa20f39b0502efdaf48c2ca7e2f58d1e3120 Mon Sep 17 00:00:00 2001
From: Alan Coopersmith <alan.coopersmith@oracle.com>
Date: Sun, 2 Nov 2025 12:16:56 -0800
Subject: [PATCH] glamor: avoid double free in glamor_make_pixmap_exportable()
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Reported by gcc 15.1:

../glamor/glamor_egl.c:320:9:
 warning: double-‘free’ of ‘modifiers’ [CWE-415] [-Wanalyzer-double-free]
[...]
           │  732 |│        free(*modifiers);
           │      |│        ~~~~~~~~~~~~~~~~
           │      |│        |
           │      |└───────>(25) ...to here
           │      |         (26) first ‘free’ here
[...]
    │  320 |         free(modifiers);
    │      |         ~~~~~~~~~~~~~~~
    │      |         |
    │      |         (28) ⚠️  second ‘free’ here; first ‘free’ was at (26)

Fixes: cef12efc1 ("glamor: Implement GetSupportedModifiers")
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2094>
---
 glamor/glamor_egl.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/glamor/glamor_egl.c b/glamor/glamor_egl.c
index 2fc63ba46..632f2f28c 100644
--- a/glamor/glamor_egl.c
+++ b/glamor/glamor_egl.c
@@ -730,6 +730,7 @@ glamor_get_modifiers(ScreenPtr screen, uint32_t format,
     if (!eglQueryDmaBufModifiersEXT(glamor_egl->display, format, num,
                                     (EGLuint64KHR *) *modifiers, NULL, &num)) {
         free(*modifiers);
+        *modifiers = NULL;
         return FALSE;
     }