1 files changed, 55 insertions, 0 deletions

diff --git a/recipes-devtools/qemu/qemu/0002-CVE-2017-2620.patch b/recipes-devtools/qemu/qemu/0002-CVE-2017-2620.patch
new file mode 100644
index 0000000..3910fb9
--- /dev/null
+++ b/recipes-devtools/qemu/qemu/0002-CVE-2017-2620.patch
@@ -0,0 +1,55 @@
+From fc8e94c3e5e74437c4e73a5582f17cfd4cae5ccf Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Wed, 8 Feb 2017 11:18:36 +0100
+Subject: [PATCH] cirrus: add blit_is_unsafe call to cirrus_bitblt_cputovideo
+ (CVE-2017-2620)
+
+CIRRUS_BLTMODE_MEMSYSSRC blits do NOT check blit destination
+and blit width, at all.  Oops.  Fix it.
+
+Security impact: high.
+
+The missing blit destination check allows to write to host memory.
+Basically same as CVE-2014-8106 for the other blit variants.
+
+CVE: CVE-2017-2620
+Upstream-Status: Backport
+
+Cc: qemu-stable@nongnu.org
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+(cherry picked from commit 92f2b88cea48c6aeba8de568a45f2ed958f3c298)
+Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
+Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
+---
+ hw/display/cirrus_vga.c | 8 ++++++++
+ 1 file changed, 8 insertions(+)
+
+diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c
+index 629a5c8..6766349 100644
+--- a/hw/display/cirrus_vga.c
++++ b/hw/display/cirrus_vga.c
+@@ -873,6 +873,10 @@ static int cirrus_bitblt_cputovideo(CirrusVGAState * s)
+ {
+     int w;
+ 
++    if (blit_is_unsafe(s, true)) {
++        return 0;
++    }
++
+     s->cirrus_blt_mode &= ~CIRRUS_BLTMODE_MEMSYSSRC;
+     s->cirrus_srcptr = &s->cirrus_bltbuf[0];
+     s->cirrus_srcptr_end = &s->cirrus_bltbuf[0];
+@@ -898,6 +902,10 @@ static int cirrus_bitblt_cputovideo(CirrusVGAState * s)
+        }
+         s->cirrus_srccounter = s->cirrus_blt_srcpitch * s->cirrus_blt_height;
+     }
++
++    /* the blit_is_unsafe call above should catch this */
++    assert(s->cirrus_blt_srcpitch <= CIRRUS_BLTBUFSIZE);
++
+     s->cirrus_srcptr = s->cirrus_bltbuf;
+     s->cirrus_srcptr_end = s->cirrus_bltbuf + s->cirrus_blt_srcpitch;
+     cirrus_update_memory_access(s);
+-- 
+1.9.1
+