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 <fangyi...@huawei.com>
Signed-off-by: hangaohuai <hangaoh...@huawei.com>
---
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..12a15e0 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 (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 (srcpitch < 0 || dstpitch < 0) {
+ return;
+ }
+
for (y = 0; y < bltheight; y++) {
for (x = 0; x < bltwidth; x+=2) {
p1 = *dst;
--
1.8.3.1
