ui/cursor: fix integer overflow in cursor_alloc (CVE-2021-4206)

Prevent potential integer overflow by limiting 'width' and 'height' to
512x512. Also change 'datasize' type to size_t. Refer to security
advisory https://starlabs.sg/advisories/22-4206/ for more information.

Fixes: CVE-2021-4206
Signed-off-by: Mauro Matteo Cascella <mcascell@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220407081712.345609-1-mcascell@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
Mauro Matteo Cascella 2022-04-07 10:17:12 +02:00 committed by Gerd Hoffmann
parent 9569f5cb5b
commit fa892e9abb
3 changed files with 16 additions and 1 deletions

View file

@ -46,6 +46,8 @@ static QEMUCursor *cursor_parse_xpm(const char *xpm[])
/* parse pixel data */
c = cursor_alloc(width, height);
assert(c != NULL);
for (pixel = 0, y = 0; y < height; y++, line++) {
for (x = 0; x < height; x++, pixel++) {
idx = xpm[line][x];
@ -91,7 +93,11 @@ QEMUCursor *cursor_builtin_left_ptr(void)
QEMUCursor *cursor_alloc(int width, int height)
{
QEMUCursor *c;
int datasize = width * height * sizeof(uint32_t);
size_t datasize = width * height * sizeof(uint32_t);
if (width > 512 || height > 512) {
return NULL;
}
c = g_malloc0(sizeof(QEMUCursor) + datasize);
c->width = width;