qemu: fix CVE-2020-15863

(From OE-Core rev: d6eb50dfe66838e6bea061cbd1a120981777b700)

Signed-off-by: Lee Chee Yang <chee.yang.lee@intel.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 64 insertions, 0 deletions

diff --git a/meta/recipes-devtools/qemu/qemu.inc b/meta/recipes-devtools/qemu/qemu.inc
index 24b0379de4..49dbb1c13d 100644
--- a/meta/recipes-devtools/qemu/qemu.inc
+++ b/meta/recipes-devtools/qemu/qemu.inc
@@ -44,6 +44,7 @@ SRC_URI = "https://download.qemu.org/${BPN}-${PV}.tar.xz \
            file://CVE-2020-13659.patch \
            file://CVE-2020-13800.patch \
            file://CVE-2020-13362.patch \
+           file://CVE-2020-15863.patch \
            "
 UPSTREAM_CHECK_REGEX = "qemu-(?P<pver>\d+(\.\d+)+)\.tar"
 
diff --git a/meta/recipes-devtools/qemu/qemu/CVE-2020-15863.patch b/meta/recipes-devtools/qemu/qemu/CVE-2020-15863.patch
new file mode 100644
index 0000000000..1505c7eed0
--- /dev/null
+++ b/meta/recipes-devtools/qemu/qemu/CVE-2020-15863.patch
@@ -0,0 +1,63 @@
+From 5519724a13664b43e225ca05351c60b4468e4555 Mon Sep 17 00:00:00 2001
+From: Mauro Matteo Cascella <mcascell@redhat.com>
+Date: Fri, 10 Jul 2020 11:19:41 +0200
+Subject: [PATCH] hw/net/xgmac: Fix buffer overflow in xgmac_enet_send()
+
+A buffer overflow issue was reported by Mr. Ziming Zhang, CC'd here. It
+occurs while sending an Ethernet frame due to missing break statements
+and improper checking of the buffer size.
+
+Reported-by: Ziming Zhang <ezrakiez@gmail.com>
+Signed-off-by: Mauro Matteo Cascella <mcascell@redhat.com>
+Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
+Signed-off-by: Jason Wang <jasowang@redhat.com>
+
+Upstream-Status: Backport [https://git.qemu.org/?p=qemu.git;a=commitdiff;h=5519724a13664b43e225ca05351c60b4468e4555]
+CVE: CVE-2020-15863
+Signed-off-by: Chee Yang Lee <chee.yang.lee@intel.com>
+
+---
+ hw/net/xgmac.c | 14 ++++++++++++--
+ 1 file changed, 12 insertions(+), 2 deletions(-)
+
+diff --git a/hw/net/xgmac.c b/hw/net/xgmac.c
+index 574dd47..5bf1b61 100644
+--- a/hw/net/xgmac.c
++++ b/hw/net/xgmac.c
+@@ -220,21 +220,31 @@ static void xgmac_enet_send(XgmacState *s)
+         }
+         len = (bd.buffer1_size & 0xfff) + (bd.buffer2_size & 0xfff);
+ 
++        /*
++         * FIXME: these cases of malformed tx descriptors (bad sizes)
++         * should probably be reported back to the guest somehow
++         * rather than simply silently stopping processing, but we
++         * don't know what the hardware does in this situation.
++         * This will only happen for buggy guests anyway.
++         */
+         if ((bd.buffer1_size & 0xfff) > 2048) {
+             DEBUGF_BRK("qemu:%s:ERROR...ERROR...ERROR... -- "
+                         "xgmac buffer 1 len on send > 2048 (0x%x)\n",
+                          __func__, bd.buffer1_size & 0xfff);
++            break;
+         }
+         if ((bd.buffer2_size & 0xfff) != 0) {
+             DEBUGF_BRK("qemu:%s:ERROR...ERROR...ERROR... -- "
+                         "xgmac buffer 2 len on send != 0 (0x%x)\n",
+                         __func__, bd.buffer2_size & 0xfff);
++            break;
+         }
+-        if (len >= sizeof(frame)) {
++        if (frame_size + len >= sizeof(frame)) {
+             DEBUGF_BRK("qemu:%s: buffer overflow %d read into %zu "
+-                        "buffer\n" , __func__, len, sizeof(frame));
++                        "buffer\n" , __func__, frame_size + len, sizeof(frame));
+             DEBUGF_BRK("qemu:%s: buffer1.size=%d; buffer2.size=%d\n",
+                         __func__, bd.buffer1_size, bd.buffer2_size);
++            break;
+         }
+ 
+         cpu_physical_memory_read(bd.buffer1_addr, ptr, len);
+-- 
+1.8.3.1
+