[[master][PATCH 1/2] qemu: Security fix CVE-2016-2197

[Armin Kuster <akuster808@gmail.com>]

From: Armin Kuster <akuster@mvista.com>

CVE-2016-2197 Qemu: ide: ahci null pointer dereference when using FIS CLB engines

Signed-off-by: Armin Kuster <akuster@mvista.com>
---
 .../recipes-devtools/qemu/qemu/CVE-2016-2197.patch | 59 ++++++++++++++++++++++
 meta/recipes-devtools/qemu/qemu_2.5.0.bb           |  1 +
 2 files changed, 60 insertions(+)
 create mode 100644 meta/recipes-devtools/qemu/qemu/CVE-2016-2197.patch

diff --git a/meta/recipes-devtools/qemu/qemu/CVE-2016-2197.patch b/meta/recipes-devtools/qemu/qemu/CVE-2016-2197.patch
new file mode 100644
index 0000000..946435c
--- /dev/null
+++ b/meta/recipes-devtools/qemu/qemu/CVE-2016-2197.patch
@@ -0,0 +1,59 @@
+From: Prasad J Pandit <address@hidden>
+
+When IDE AHCI emulation uses Frame Information Structures(FIS)
+engine for data transfer, the mapped FIS buffer address is stored
+in a static 'bounce.buffer'. When a request is made to map another
+memory region, address_space_map() returns NULL because
+'bounce.buffer' is in_use. It leads to a null pointer dereference
+error while doing 'dma_memory_unmap'. Add a check to avoid it.
+
+Reported-by: Zuozhi fzz <address@hidden>
+Signed-off-by: Prasad J Pandit <address@hidden>
+
+Upstream-Status: Backport
+https://lists.gnu.org/archive/html/qemu-devel/2016-01/msg05740.html
+
+CVE: CVE-2016-2197
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ hw/ide/ahci.c | 16 ++++++++++------
+  1 file changed, 10 insertions(+), 6 deletions(-)
+
+  Update as per review
+    -> https://lists.gnu.org/archive/html/qemu-devel/2016-01/msg05715.html
+
+Index: qemu-2.5.0/hw/ide/ahci.c
+===================================================================
+--- qemu-2.5.0.orig/hw/ide/ahci.c
++++ qemu-2.5.0/hw/ide/ahci.c
+@@ -661,9 +661,11 @@ static bool ahci_map_fis_address(AHCIDev
+ 
+ static void ahci_unmap_fis_address(AHCIDevice *ad)
+ {
+-    dma_memory_unmap(ad->hba->as, ad->res_fis, 256,
+-                     DMA_DIRECTION_FROM_DEVICE, 256);
+-    ad->res_fis = NULL;
++    if (ad->res_fis) {
++        dma_memory_unmap(ad->hba->as, ad->res_fis, 256,
++                         DMA_DIRECTION_FROM_DEVICE, 256);
++        ad->res_fis = NULL;
++    }
+ }
+ 
+ static bool ahci_map_clb_address(AHCIDevice *ad)
+@@ -677,9 +679,11 @@ static bool ahci_map_clb_address(AHCIDev
+ 
+ static void ahci_unmap_clb_address(AHCIDevice *ad)
+ {
+-    dma_memory_unmap(ad->hba->as, ad->lst, 1024,
+-                     DMA_DIRECTION_FROM_DEVICE, 1024);
+-    ad->lst = NULL;
++    if (ad->lst) {
++        dma_memory_unmap(ad->hba->as, ad->lst, 1024,
++                         DMA_DIRECTION_FROM_DEVICE, 1024);
++        ad->lst = NULL;
++    }
+ }
+ 
+ static void ahci_write_fis_sdb(AHCIState *s, NCQTransferState *ncq_tfs)
diff --git a/meta/recipes-devtools/qemu/qemu_2.5.0.bb b/meta/recipes-devtools/qemu/qemu_2.5.0.bb
index e51ec16..3e7df2f 100644
--- a/meta/recipes-devtools/qemu/qemu_2.5.0.bb
+++ b/meta/recipes-devtools/qemu/qemu_2.5.0.bb
@@ -8,6 +8,7 @@ SRC_URI += "file://configure-fix-Darwin-target-detection.patch \
             file://Qemu-Arm-versatilepb-Add-memory-size-checking.patch \
             file://no-valgrind.patch \
             file://CVE-2016-1568.patch \
+            file://CVE-2016-2197.patch \
            "
 SRC_URI_prepend = "http://wiki.qemu-project.org/download/${BP}.tar.bz2"
 SRC_URI[md5sum] = "f469f2330bbe76e3e39db10e9ac4f8db"
-- 
2.3.5