xserver: Branch 'server-1.20-branch'

[GitLab Mirror]

 hw/xfree86/common/xf86Config.c |   23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

New commits:
commit e49738f0c9d4370c7a7e6e86c2c74151aa2e33fa
Author: Zoltán Böszörményi <zboszor at pr.hu>
Date:   Mon Jun 21 12:12:41 2021 +0200

    xfree86: Fix NULL pointer dereference crash
    
    screenp->displays[count] (passed to configDisplay() in
    configScreen()) is NULL if there is no Virtual setting
    in the configuration.
    
    Fixes: f8a6be04d0c7e6a99824ff888ad6c010960c5c21 ("xfree86: Change
    displays array to pointers array to fix invalid pointer issues
    after table reallocation")
    
    Signed-off-by: Zoltán Böszörményi <zboszor at gmail.com>
    (cherry picked from commit ef89b6648e2a806237a6d2fa598e1b9c83f128b4)

diff --git a/hw/xfree86/common/xf86Config.c b/hw/xfree86/common/xf86Config.c
index 312597c7e..09d27ecb7 100644
--- a/hw/xfree86/common/xf86Config.c
+++ b/hw/xfree86/common/xf86Config.c
@@ -1763,24 +1763,21 @@ configScreen(confScreenPtr screenp, XF86ConfScreenPtr conf_screen, int scrnum,
     screenp->displays = xnfallocarray(count, sizeof(DispPtr));
     screenp->numdisplays = count;
 
-    /* Fill in the default Virtual size, if any */
-    if (conf_screen->scrn_virtualX && conf_screen->scrn_virtualY) {
-        for (count = 0, dispptr = conf_screen->scrn_display_lst;
-             dispptr;
-             dispptr = (XF86ConfDisplayPtr) dispptr->list.next, count++) {
-            screenp->displays[count] = xnfcalloc(1, sizeof(DispRec));
+    for (count = 0, dispptr = conf_screen->scrn_display_lst;
+         dispptr;
+         dispptr = (XF86ConfDisplayPtr) dispptr->list.next, count++) {
+
+        /* Allocate individual Display records */
+        screenp->displays[count] = xnfcalloc(1, sizeof(DispRec));
+
+        /* Fill in the default Virtual size, if any */
+        if (conf_screen->scrn_virtualX && conf_screen->scrn_virtualY) {
             screenp->displays[count]->virtualX = conf_screen->scrn_virtualX;
             screenp->displays[count]->virtualY = conf_screen->scrn_virtualY;
         }
-    }
 
-    /* Now do the per-Display Virtual sizes */
-    count = 0;
-    dispptr = conf_screen->scrn_display_lst;
-    while (dispptr) {
+        /* Now do the per-Display Virtual sizes */
         configDisplay(screenp->displays[count], dispptr);
-        count++;
-        dispptr = (XF86ConfDisplayPtr) dispptr->list.next;
     }
 
     /*