From: BALATON Zoltan <balaton@eik.bme.hu>
Date: Sun, 21 Jun 2020 11:12:38 +0000 (+0200)
Subject: ati-vga: Do not assert on error
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=41977c65c04a85f177603778cb60e06847efd3af;p=qemu.git

ati-vga: Do not assert on error

Do not abort on unsupported value just print log and continue. While
display will likely be broken this prevents malicious guest to crash
QEMU causing denial of service.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Message-id: 0c13dab5d8e3b7e7479c3edbf53aeac8c09de6de.1592737958.git.balaton@eik.bme.hu
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---

diff --git a/hw/display/ati.c b/hw/display/ati.c
index 245130d52f..95fc443cac 100644
--- a/hw/display/ati.c
+++ b/hw/display/ati.c
@@ -86,8 +86,8 @@ static void ati_vga_switch_mode(ATIVGAState *s)
                 break;
             default:
                 qemu_log_mask(LOG_UNIMP, "Unsupported bpp value\n");
+                return;
             }
-            assert(bpp != 0);
             DPRINTF("Switching to %dx%d %d %d @ %x\n", h, v, stride, bpp, offs);
             vbe_ioport_write_index(&s->vga, 0, VBE_DISPI_INDEX_ENABLE);
             vbe_ioport_write_data(&s->vga, 0, VBE_DISPI_DISABLED);