[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH] cirrus: keep vga vram pointer within bounds
From: |
P J P |
Subject: |
[Qemu-devel] [PATCH] cirrus: keep vga vram pointer within bounds |
Date: |
Wed, 11 Oct 2017 03:06:08 +0530 |
From: Prasad J Pandit <address@hidden>
'dst' pointer could exceed vga vram size when writing to the
cirrus memory area; it'd lead to an OOB access issue. Add check
to avoid it.
Reported-by: Niu Guoxiang <address@hidden>
Signed-off-by: Prasad J Pandit <address@hidden>
---
hw/display/cirrus_vga.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c
index afc290ab91..451a736262 100644
--- a/hw/display/cirrus_vga.c
+++ b/hw/display/cirrus_vga.c
@@ -2047,8 +2047,11 @@ static void
cirrus_mem_writeb_mode4and5_8bpp(CirrusVGAState * s,
}
val <<= 1;
dst++;
+ if (dst >= s->vga.vram_ptr + s->vga.vram_size) {
+ break;
+ }
}
- memory_region_set_dirty(&s->vga.vram, offset, 8);
+ memory_region_set_dirty(&s->vga.vram, offset, x);
}
static void cirrus_mem_writeb_mode4and5_16bpp(CirrusVGAState * s,
@@ -2071,8 +2074,11 @@ static void
cirrus_mem_writeb_mode4and5_16bpp(CirrusVGAState * s,
}
val <<= 1;
dst += 2;
+ if (dst >= s->vga.vram_ptr + s->vga.vram_size) {
+ break;
+ }
}
- memory_region_set_dirty(&s->vga.vram, offset, 16);
+ memory_region_set_dirty(&s->vga.vram, offset, x<<1);
}
/***************************************
--
2.13.6
- [Qemu-devel] [PATCH] cirrus: keep vga vram pointer within bounds,
P J P <=