File 0303-display-cirrus-ignore-source-pitch-.patch of Package qemu.4227

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File 0303-display-cirrus-ignore-source-pitch-.patch of Package qemu.4227

From 92134c0f59fb70a2c4e7f3cbd633e72a1ed147ed Mon Sep 17 00:00:00 2001
From: Bruce Rogers <brogers@suse.com>
Date: Mon, 9 Jan 2017 13:35:20 -0700
Subject: [PATCH] display: cirrus: ignore source pitch value as needed in
 blit_is_unsafe

Commit 4299b90 added a check which is too broad, given that the source
pitch value is not required to be initialized for solid fill operations.
This patch refines the blit_is_unsafe() check to ignore source pitch in
that case. After applying the above commit as a security patch, we
noticed the SLES 11 SP4 guest gui failed to initialize properly.

Signed-off-by: Bruce Rogers <brogers@suse.com>
Message-id: 20170109203520.5619-1-brogers@suse.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit 913a87885f589d263e682c2eb6637c6e14538061)
[BR: BSC#1016779]
Signed-off-by: Bruce Rogers <brogers@suse.com>
---
 hw/display/cirrus_vga.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c
index 7942229eed..80e16aade2 100644
--- a/hw/display/cirrus_vga.c
+++ b/hw/display/cirrus_vga.c
@@ -289,7 +289,7 @@ static bool blit_region_is_unsafe(struct CirrusVGAState *s,
     return false;
 }
 
-static bool blit_is_unsafe(struct CirrusVGAState *s)
+static bool blit_is_unsafe(struct CirrusVGAState *s, bool dst_only)
 {
     /* should be the case, see cirrus_bitblt_start */
     assert(s->cirrus_blt_width > 0);
@@ -303,6 +303,9 @@ static bool blit_is_unsafe(struct CirrusVGAState *s)
                               s->cirrus_blt_dstaddr & s->cirrus_addr_mask)) {
         return true;
     }
+    if (dst_only) {
+        return false;
+    }
     if (blit_region_is_unsafe(s, s->cirrus_blt_srcpitch,
                               s->cirrus_blt_srcaddr & s->cirrus_addr_mask)) {
         return true;
@@ -668,7 +671,7 @@ static int cirrus_bitblt_common_patterncopy(CirrusVGAState * s,
 
     dst = s->vga.vram_ptr + (s->cirrus_blt_dstaddr & s->cirrus_addr_mask);
 
-    if (blit_is_unsafe(s))
+    if (blit_is_unsafe(s, false))
         return 0;
 
     (*s->cirrus_rop) (s, dst, src,
@@ -686,7 +689,7 @@ static int cirrus_bitblt_solidfill(CirrusVGAState *s, int blt_rop)
 {
     cirrus_fill_t rop_func;
 
-    if (blit_is_unsafe(s)) {
+    if (blit_is_unsafe(s, true)) {
         return 0;
     }
     rop_func = cirrus_fill[rop_to_index[blt_rop]][s->cirrus_blt_pixelwidth - 1];
@@ -790,7 +793,7 @@ static int cirrus_do_copy(CirrusVGAState *s, int dst, int src, int w, int h)
 
 static int cirrus_bitblt_videotovideo_copy(CirrusVGAState * s)
 {
-    if (blit_is_unsafe(s))
+    if (blit_is_unsafe(s, false))
         return 0;
 
     return cirrus_do_copy(s, s->cirrus_blt_dstaddr - s->vga.start_addr,

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File 0303-display-cirrus-ignore-source-pitch-.patch of Package qemu.4227

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