From 1663ffb9157e3dc17d14741f6cd6c48bfffde9d0 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 18 Aug 2023 16:10:55 +0100 Subject: ui/spice-display: Avoid dynamic stack allocation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Use an autofree heap allocation instead of a variable-length array on the stack in qemu_spice_create_update(). The codebase has very few VLAs, and if we can get rid of them all we can make the compiler error on new additions. This is a defensive measure against security bugs where an on-stack dynamic allocation isn't correctly size-checked (e.g. CVE-2021-3527). Signed-off-by: Peter Maydell Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Marc-André Lureau Message-Id: <20230818151057.1541189-2-peter.maydell@linaro.org> --- ui/spice-display.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/ui/spice-display.c b/ui/spice-display.c index 3f3f801..0e2fbfb 100644 --- a/ui/spice-display.c +++ b/ui/spice-display.c @@ -189,7 +189,7 @@ static void qemu_spice_create_update(SimpleSpiceDisplay *ssd) { static const int blksize = 32; int blocks = DIV_ROUND_UP(surface_width(ssd->ds), blksize); - int dirty_top[blocks]; + g_autofree int *dirty_top = NULL; int y, yoff1, yoff2, x, xoff, blk, bw; int bpp = surface_bytes_per_pixel(ssd->ds); uint8_t *guest, *mirror; @@ -198,6 +198,7 @@ static void qemu_spice_create_update(SimpleSpiceDisplay *ssd) return; }; + dirty_top = g_new(int, blocks); for (blk = 0; blk < blocks; blk++) { dirty_top[blk] = -1; } -- cgit v1.1