diff -Nru qemu-4.2/debian/changelog qemu-4.2/debian/changelog
--- qemu-4.2/debian/changelog	2020-08-19 11:40:49.000000000 +0000
+++ qemu-4.2/debian/changelog	2020-09-15 14:02:08.000000000 +0000
@@ -1,3 +1,12 @@
+qemu (1:4.2-3ubuntu6.6) focal-security; urgency=medium
+
+  * SECURITY UPDATE: out-of-bounds read/write in USB emulator
+    - debian/patches/ubuntu/CVE-2020-14364.patch: fix setup_len init in
+      hw/usb/core.c.
+    - CVE-2020-14364
+
+ -- Marc Deslauriers <marc.deslauriers@ubuntu.com>  Tue, 15 Sep 2020 10:02:08 -0400
+
 qemu (1:4.2-3ubuntu6.5) focal; urgency=medium
 
   * further stabilize qemu by importing patches of qemu v4.2.1
diff -Nru qemu-4.2/debian/patches/series qemu-4.2/debian/patches/series
--- qemu-4.2/debian/patches/series	2020-08-19 11:40:49.000000000 +0000
+++ qemu-4.2/debian/patches/series	2020-09-15 14:01:46.000000000 +0000
@@ -224,3 +224,4 @@
 ubuntu/lp-1883984-target-s390x-Fix-SQXBR.patch
 ubuntu/lp-1890154-s390x-protvirt-allow-to-IPL-secure-guests-with-no-re.patch
 ubuntu/hw-riscv-Allow-64-bit-access-to-SiFive-CLINT.patch
+ubuntu/CVE-2020-14364.patch
diff -Nru qemu-4.2/debian/patches/ubuntu/CVE-2020-14364.patch qemu-4.2/debian/patches/ubuntu/CVE-2020-14364.patch
--- qemu-4.2/debian/patches/ubuntu/CVE-2020-14364.patch	1970-01-01 00:00:00.000000000 +0000
+++ qemu-4.2/debian/patches/ubuntu/CVE-2020-14364.patch	2020-09-15 14:01:07.000000000 +0000
@@ -0,0 +1,88 @@
+From b946434f2659a182afc17e155be6791ebfb302eb Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Tue, 25 Aug 2020 07:36:36 +0200
+Subject: [PATCH] usb: fix setup_len init (CVE-2020-14364)
+
+Store calculated setup_len in a local variable, verify it, and only
+write it to the struct (USBDevice->setup_len) in case it passed the
+sanity checks.
+
+This prevents other code (do_token_{in,out} functions specifically)
+from working with invalid USBDevice->setup_len values and overrunning
+the USBDevice->setup_buf[] buffer.
+
+Fixes: CVE-2020-14364
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Tested-by: Gonglei <arei.gonglei@huawei.com>
+Reviewed-by: Li Qiang <liq3ea@gmail.com>
+Message-id: 20200825053636.29648-1-kraxel@redhat.com
+---
+ hw/usb/core.c | 16 ++++++++++------
+ 1 file changed, 10 insertions(+), 6 deletions(-)
+
+diff --git a/hw/usb/core.c b/hw/usb/core.c
+index 5abd128..5234dcc 100644
+--- a/hw/usb/core.c
++++ b/hw/usb/core.c
+@@ -129,6 +129,7 @@ void usb_wakeup(USBEndpoint *ep, unsigned int stream)
+ static void do_token_setup(USBDevice *s, USBPacket *p)
+ {
+     int request, value, index;
++    unsigned int setup_len;
+ 
+     if (p->iov.size != 8) {
+         p->status = USB_RET_STALL;
+@@ -138,14 +139,15 @@ static void do_token_setup(USBDevice *s, USBPacket *p)
+     usb_packet_copy(p, s->setup_buf, p->iov.size);
+     s->setup_index = 0;
+     p->actual_length = 0;
+-    s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];
+-    if (s->setup_len > sizeof(s->data_buf)) {
++    setup_len = (s->setup_buf[7] << 8) | s->setup_buf[6];
++    if (setup_len > sizeof(s->data_buf)) {
+         fprintf(stderr,
+                 "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",
+-                s->setup_len, sizeof(s->data_buf));
++                setup_len, sizeof(s->data_buf));
+         p->status = USB_RET_STALL;
+         return;
+     }
++    s->setup_len = setup_len;
+ 
+     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
+     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
+@@ -259,26 +261,28 @@ static void do_token_out(USBDevice *s, USBPacket *p)
+ static void do_parameter(USBDevice *s, USBPacket *p)
+ {
+     int i, request, value, index;
++    unsigned int setup_len;
+ 
+     for (i = 0; i < 8; i++) {
+         s->setup_buf[i] = p->parameter >> (i*8);
+     }
+ 
+     s->setup_state = SETUP_STATE_PARAM;
+-    s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];
+     s->setup_index = 0;
+ 
+     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
+     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
+     index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
+ 
+-    if (s->setup_len > sizeof(s->data_buf)) {
++    setup_len = (s->setup_buf[7] << 8) | s->setup_buf[6];
++    if (setup_len > sizeof(s->data_buf)) {
+         fprintf(stderr,
+                 "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",
+-                s->setup_len, sizeof(s->data_buf));
++                setup_len, sizeof(s->data_buf));
+         p->status = USB_RET_STALL;
+         return;
+     }
++    s->setup_len = setup_len;
+ 
+     if (p->pid == USB_TOKEN_OUT) {
+         usb_packet_copy(p, s->data_buf, s->setup_len);
+-- 
+1.8.3.1
+