From 8054d2c1219439f02ce7836d8efaa9732c21cab3 Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Tue, 21 Mar 2017 07:40:27 +0100 Subject: [PATCH 03/12] fix :cirrus_vga fix OOB read case qemu Segmentation fault RH-Author: Gerd Hoffmann Message-id: <1490082033-671-2-git-send-email-kraxel@redhat.com> Patchwork-id: 74409 O-Subject: [RHEL-7.3.z qemu-kvm-rhev PATCH 1/7] fix :cirrus_vga fix OOB read case qemu Segmentation fault Bugzilla: 1430061 RH-Acked-by: Dr. David Alan Gilbert RH-Acked-by: Laurent Vivier RH-Acked-by: Paolo Bonzini From: hangaohuai check the validity of parameters in cirrus_bitblt_rop_fwd_transp_xxx and cirrus_bitblt_rop_fwd_xxx to avoid the OOB read which causes qemu Segmentation fault. After the fix, we will touch the assert in cirrus_invalidate_region: assert(off_cur_end >= off_cur); Signed-off-by: fangying Signed-off-by: hangaohuai Message-id: 20170314063919.16200-1-hangaohuai@huawei.com Signed-off-by: Gerd Hoffmann (cherry picked from commit 215902d7b6fb50c6fc216fc74f770858278ed904) Signed-off-by: Miroslav Rezanina --- hw/display/cirrus_vga_rop.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/hw/display/cirrus_vga_rop.h b/hw/display/cirrus_vga_rop.h index 0925a00..b7447f8 100644 --- a/hw/display/cirrus_vga_rop.h +++ b/hw/display/cirrus_vga_rop.h @@ -97,6 +97,11 @@ glue(glue(cirrus_bitblt_rop_fwd_transp_, ROP_NAME),_8)(CirrusVGAState *s, uint8_t p; dstpitch -= bltwidth; srcpitch -= bltwidth; + + if (bltheight > 1 && (dstpitch < 0 || srcpitch < 0)) { + return; + } + for (y = 0; y < bltheight; y++) { for (x = 0; x < bltwidth; x++) { p = *dst; @@ -143,6 +148,11 @@ glue(glue(cirrus_bitblt_rop_fwd_transp_, ROP_NAME),_16)(CirrusVGAState *s, uint8_t p1, p2; dstpitch -= bltwidth; srcpitch -= bltwidth; + + if (bltheight > 1 && (dstpitch < 0 || srcpitch < 0)) { + return; + } + for (y = 0; y < bltheight; y++) { for (x = 0; x < bltwidth; x+=2) { p1 = *dst; -- 1.8.3.1