Files
xserver/hw/xwin/winmultiwindowclass.c
Enrico Weigelt, metux IT consult 6a8ee31e1b dix: move props into WindowRec and fix potential NULL deref
The pointer to the window properties is currently inside the WindowOptional
structure, which may or may not exist at any given time. Thus, before accessing
those fields, at least need to check whether it exists, potentially need to
create it first.

Since a pointer is small (in relation to WindowRec) and windows having properties
is a pretty common, we can make our life much simpler here by moving the pointer
directly into WindowRec, so we don't need extra WindowOptionalRec allocation.

This also fixes an analyzer warning on potential NULL dereference issue:

| ../dix/property.c: In function ‘dixChangeWindowProperty’:
|../dix/property.c:343:37: warning: dereference of NULL ‘*pWin.optional’ [CWE-476] [-Wanalyzer-null-dereference]
|  343 |         pProp->next = pWin->optional->userProps;
|      |                       ~~~~~~~~~~~~~~^~~~~~~~~~~

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
2025-06-12 16:34:03 +02:00

256 lines
6.8 KiB
C

/*
*Copyright (C) 1994-2000 The XFree86 Project, Inc. All Rights Reserved.
*
*Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
*"Software"), to deal in the Software without restriction, including
*without limitation the rights to use, copy, modify, merge, publish,
*distribute, sublicense, and/or sell copies of the Software, and to
*permit persons to whom the Software is furnished to do so, subject to
*the following conditions:
*
*The above copyright notice and this permission notice shall be
*included in all copies or substantial portions of the Software.
*
*THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
*EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
*MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
*NONINFRINGEMENT. IN NO EVENT SHALL THE XFREE86 PROJECT BE LIABLE FOR
*ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
*CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
*WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*Except as contained in this notice, the name of the XFree86 Project
*shall not be used in advertising or otherwise to promote the sale, use
*or other dealings in this Software without prior written authorization
*from the XFree86 Project.
*
* Authors: Earle F. Philhower, III
*/
#ifdef HAVE_XWIN_CONFIG_H
#include <xwin-config.h>
#endif
#include <X11/Xatom.h>
#include "propertyst.h"
#include "windowstr.h"
#include "winmultiwindowclass.h"
#include "win.h"
/*
* Local function
*/
DEFINE_ATOM_HELPER(AtmWmWindowRole, "WM_WINDOW_ROLE")
int
winMultiWindowGetClassHint(WindowPtr pWin, char **res_name, char **res_class)
{
int len_name, len_class;
if (!pWin || !res_name || !res_class) {
ErrorF("winMultiWindowGetClassHint - pWin, res_name, or res_class was "
"NULL\n");
return 0;
}
PropertyPtr prop = pWin->properties;
*res_name = *res_class = NULL;
while (prop) {
if (prop->propertyName == XA_WM_CLASS
&& prop->type == XA_STRING && prop->format == 8 && prop->data) {
/*
WM_CLASS property should consist of 2 null terminated strings, but we
must handle the cases when one or both is absent or not null terminated
*/
len_name = strlen((char *) prop->data);
if (len_name > prop->size) len_name = prop->size;
(*res_name) = malloc(len_name + 1);
if (!*res_name) {
ErrorF("winMultiWindowGetClassHint - *res_name was NULL\n");
return 0;
}
/* Copy name and ensure null terminated */
strncpy((*res_name), prop->data, len_name);
(*res_name)[len_name] = '\0';
/* Compute length of class name, it could be that it is absent or not null terminated */
len_class = (len_name >= prop->size) ? 0 : (strlen(((char *) prop->data) + 1 + len_name));
if (len_class > prop->size - 1 - len_name) len_class = prop->size - 1 - len_name;
(*res_class) = malloc(len_class + 1);
if (!*res_class) {
ErrorF("winMultiWindowGetClassHint - *res_class was NULL\n");
/* Free the previously allocated res_name */
free(*res_name);
return 0;
}
/* Copy class name and ensure null terminated */
strncpy((*res_class), ((char *) prop->data) + 1 + len_name, len_class);
(*res_class)[len_class] = '\0';
return 1;
}
else
prop = prop->next;
}
return 0;
}
int
winMultiWindowGetWMHints(WindowPtr pWin, WinXWMHints * hints)
{
if (!pWin || !hints) {
ErrorF("winMultiWindowGetWMHints - pWin or hints was NULL\n");
return 0;
}
PropertyPtr prop = pWin->properties;
memset(hints, 0, sizeof(WinXWMHints));
while (prop) {
if (prop->propertyName == XA_WM_HINTS && prop->data) {
memcpy(hints, prop->data, sizeof(WinXWMHints));
return 1;
}
else
prop = prop->next;
}
return 0;
}
int
winMultiWindowGetWindowRole(WindowPtr pWin, char **res_role)
{
int len_role;
if (!pWin || !res_role)
return 0;
PropertyPtr prop = pWin->properties;
*res_role = NULL;
while (prop) {
if (prop->propertyName == AtmWmWindowRole()
&& prop->type == XA_STRING && prop->format == 8 && prop->data) {
len_role = prop->size;
(*res_role) = malloc(len_role + 1);
if (!*res_role) {
ErrorF("winMultiWindowGetWindowRole - *res_role was NULL\n");
return 0;
}
strncpy((*res_role), prop->data, len_role);
(*res_role)[len_role] = 0;
return 1;
}
else
prop = prop->next;
}
return 0;
}
int
winMultiWindowGetWMNormalHints(WindowPtr pWin, WinXSizeHints * hints)
{
if (!pWin || !hints) {
ErrorF("winMultiWindowGetWMNormalHints - pWin or hints was NULL\n");
return 0;
}
PropertyPtr prop = pWin->properties;
memset(hints, 0, sizeof(WinXSizeHints));
while (prop) {
if (prop->propertyName == XA_WM_NORMAL_HINTS && prop->data) {
memcpy(hints, prop->data, sizeof(WinXSizeHints));
return 1;
}
else
prop = prop->next;
}
return 0;
}
int
winMultiWindowGetTransientFor(WindowPtr pWin, Window *pDaddyId)
{
if (!pWin) {
ErrorF("winMultiWindowGetTransientFor - pWin was NULL\n");
return 0;
}
PropertyPtr prop = pWin->properties;
if (pDaddyId)
*pDaddyId = 0;
while (prop) {
if (prop->propertyName == XA_WM_TRANSIENT_FOR) {
if (pDaddyId)
memcpy(pDaddyId, prop->data, sizeof(Window));
return 1;
}
else
prop = prop->next;
}
return 0;
}
int
winMultiWindowGetWMName(WindowPtr pWin, char **wmName)
{
int len_name;
if (!pWin || !wmName) {
ErrorF("winMultiWindowGetClassHint - pWin, res_name, or res_class was "
"NULL\n");
return 0;
}
PropertyPtr prop = pWin->properties;
*wmName = NULL;
while (prop) {
if (prop->propertyName == XA_WM_NAME
&& prop->type == XA_STRING && prop->data) {
len_name = prop->size;
(*wmName) = malloc(len_name + 1);
if (!*wmName) {
ErrorF("winMultiWindowGetWMName - *wmName was NULL\n");
return 0;
}
strncpy((*wmName), prop->data, len_name);
(*wmName)[len_name] = 0;
return 1;
}
else
prop = prop->next;
}
return 0;
}