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| author | Prasad J Pandit <pjp@fedoraproject.org> | 2016-10-18 13:15:17 +0530 |
|---|---|---|
| committer | Gerd Hoffmann <kraxel@redhat.com> | 2016-12-05 11:01:55 +0100 |
| commit | 4299b90e9ba9ce5ca9024572804ba751aa1a7e70 (patch) | |
| tree | 1ccd2cdab99576b791e53ad97f20a8cc9ae94984 /hw/display/cirrus_vga.c | |
| parent | 2d1cd6c7a91a4beb99a0c3a21be529222a708545 (diff) | |
| download | qemu-4299b90e9ba9ce5ca9024572804ba751aa1a7e70.zip qemu-4299b90e9ba9ce5ca9024572804ba751aa1a7e70.tar.gz qemu-4299b90e9ba9ce5ca9024572804ba751aa1a7e70.tar.bz2 | |
display: cirrus: check vga bits per pixel(bpp) value
In Cirrus CLGD 54xx VGA Emulator, if cirrus graphics mode is VGA,
'cirrus_get_bpp' returns zero(0), which could lead to a divide
by zero error in while copying pixel data. The same could occur
via blit pitch values. Add check to avoid it.
Reported-by: Huawei PSIRT <psirt@huawei.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-id: 1476776717-24807-1-git-send-email-ppandit@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Diffstat (limited to 'hw/display/cirrus_vga.c')
| -rw-r--r-- | hw/display/cirrus_vga.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c index 3d712d5..bdb092e 100644 --- a/hw/display/cirrus_vga.c +++ b/hw/display/cirrus_vga.c @@ -272,6 +272,9 @@ static void cirrus_update_memory_access(CirrusVGAState *s); static bool blit_region_is_unsafe(struct CirrusVGAState *s, int32_t pitch, int32_t addr) { + if (!pitch) { + return true; + } if (pitch < 0) { int64_t min = addr + ((int64_t)s->cirrus_blt_height-1) * pitch; @@ -715,7 +718,7 @@ static int cirrus_bitblt_videotovideo_patterncopy(CirrusVGAState * s) s->cirrus_addr_mask)); } -static void cirrus_do_copy(CirrusVGAState *s, int dst, int src, int w, int h) +static int cirrus_do_copy(CirrusVGAState *s, int dst, int src, int w, int h) { int sx = 0, sy = 0; int dx = 0, dy = 0; @@ -729,6 +732,9 @@ static void cirrus_do_copy(CirrusVGAState *s, int dst, int src, int w, int h) int width, height; depth = s->vga.get_bpp(&s->vga) / 8; + if (!depth) { + return 0; + } s->vga.get_resolution(&s->vga, &width, &height); /* extra x, y */ @@ -783,6 +789,8 @@ static void cirrus_do_copy(CirrusVGAState *s, int dst, int src, int w, int h) cirrus_invalidate_region(s, s->cirrus_blt_dstaddr, s->cirrus_blt_dstpitch, s->cirrus_blt_width, s->cirrus_blt_height); + + return 1; } static int cirrus_bitblt_videotovideo_copy(CirrusVGAState * s) @@ -790,11 +798,9 @@ static int cirrus_bitblt_videotovideo_copy(CirrusVGAState * s) if (blit_is_unsafe(s)) return 0; - cirrus_do_copy(s, s->cirrus_blt_dstaddr - s->vga.start_addr, + return cirrus_do_copy(s, s->cirrus_blt_dstaddr - s->vga.start_addr, s->cirrus_blt_srcaddr - s->vga.start_addr, s->cirrus_blt_width, s->cirrus_blt_height); - - return 1; } /*************************************** |