| From fa892e9abb728e76afcf27323ab29c57fb0fe7aa Mon Sep 17 00:00:00 2001 |
| From: Mauro Matteo Cascella <mcascell@redhat.com> |
| Date: Thu, 7 Apr 2022 10:17:12 +0200 |
| Subject: [PATCH] ui/cursor: fix integer overflow in cursor_alloc |
| (CVE-2021-4206) |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=utf8 |
| Content-Transfer-Encoding: 8bit |
| |
| 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> |
| |
| Upstream-Status: Backport |
| https://git.qemu.org/?p=qemu.git;a=commit;h=fa892e9abb728e76afcf27323ab29c57fb0fe7aa |
| |
| Signed-off-by: Davide Gardenal <davide.gardenal@huawei.com> |
| --- |
| hw/display/qxl-render.c | 7 +++++++ |
| hw/display/vmware_vga.c | 2 ++ |
| ui/cursor.c | 8 +++++++- |
| 3 files changed, 16 insertions(+), 1 deletion(-) |
| |
| diff --git a/hw/display/qxl-render.c b/hw/display/qxl-render.c |
| index 237ed29..ca21700 100644 |
| --- a/hw/display/qxl-render.c |
| +++ b/hw/display/qxl-render.c |
| @@ -247,6 +247,13 @@ static QEMUCursor *qxl_cursor(PCIQXLDevice *qxl, QXLCursor *cursor, |
| size_t size; |
| |
| c = cursor_alloc(cursor->header.width, cursor->header.height); |
| + |
| + if (!c) { |
| + qxl_set_guest_bug(qxl, "%s: cursor %ux%u alloc error", __func__, |
| + cursor->header.width, cursor->header.height); |
| + goto fail; |
| + } |
| + |
| c->hot_x = cursor->header.hot_spot_x; |
| c->hot_y = cursor->header.hot_spot_y; |
| switch (cursor->header.type) { |
| diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c |
| index 98c8347..45d06cb 100644 |
| --- a/hw/display/vmware_vga.c |
| +++ b/hw/display/vmware_vga.c |
| @@ -515,6 +515,8 @@ static inline void vmsvga_cursor_define(struct vmsvga_state_s *s, |
| int i, pixels; |
| |
| qc = cursor_alloc(c->width, c->height); |
| + assert(qc != NULL); |
| + |
| qc->hot_x = c->hot_x; |
| qc->hot_y = c->hot_y; |
| switch (c->bpp) { |
| diff --git a/ui/cursor.c b/ui/cursor.c |
| index 1d62ddd..835f080 100644 |
| --- a/ui/cursor.c |
| +++ b/ui/cursor.c |
| @@ -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; |
| -- |
| 1.8.3.1 |
| |