qemu: fix CVE-2021-3527

(From OE-Core rev: 6774efd1e3d0bd5c8c34f84dcf4f698d7eafb36a)

Signed-off-by: Lee Chee Yang <chee.yang.lee@intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 101 insertions, 0 deletions

diff --git a/meta/recipes-devtools/qemu/qemu/CVE-2021-3527-1.patch b/meta/recipes-devtools/qemu/qemu/CVE-2021-3527-1.patch
new file mode 100644
index 0000000000..77a5385692
--- /dev/null
+++ b/meta/recipes-devtools/qemu/qemu/CVE-2021-3527-1.patch
@@ -0,0 +1,42 @@
+From 05a40b172e4d691371534828078be47e7fff524c Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Mon, 3 May 2021 15:29:15 +0200
+Subject: [PATCH] usb: limit combined packets to 1 MiB (CVE-2021-3527)
+
+usb-host and usb-redirect try to batch bulk transfers by combining many
+small usb packets into a single, large transfer request, to reduce the
+overhead and improve performance.
+
+This patch adds a size limit of 1 MiB for those combined packets to
+restrict the host resources the guest can bind that way.
+
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Message-Id: <20210503132915.2335822-6-kraxel@redhat.com>
+
+Upstream-Status: Backport
+https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fff524c
+CVE: CVE-2021-3527
+Signed-off-by: Chee Yang Lee <chee.yang.lee@intel.com>
+
+---
+ hw/usb/combined-packet.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/hw/usb/combined-packet.c b/hw/usb/combined-packet.c
+index 5d57e883dc..e56802f89a 100644
+--- a/hw/usb/combined-packet.c
++++ b/hw/usb/combined-packet.c
+@@ -171,7 +171,9 @@ void usb_ep_combine_input_packets(USBEndpoint *ep)
+         if ((p->iov.size % ep->max_packet_size) != 0 || !p->short_not_ok ||
+                 next == NULL ||
+                 /* Work around for Linux usbfs bulk splitting + migration */
+-                (totalsize == (16 * KiB - 36) && p->int_req)) {
++                (totalsize == (16 * KiB - 36) && p->int_req) ||
++                /* Next package may grow combined package over 1MiB */
++                totalsize > 1 * MiB - ep->max_packet_size) {
+             usb_device_handle_data(ep->dev, first);
+             assert(first->status == USB_RET_ASYNC);
+             if (first->combined) {
+-- 
+GitLab
+
diff --git a/meta/recipes-devtools/qemu/qemu/CVE-2021-3527-2.patch b/meta/recipes-devtools/qemu/qemu/CVE-2021-3527-2.patch
new file mode 100644
index 0000000000..6371aced12
--- /dev/null
+++ b/meta/recipes-devtools/qemu/qemu/CVE-2021-3527-2.patch
@@ -0,0 +1,59 @@
+From 7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986 Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Mon, 3 May 2021 15:29:12 +0200
+Subject: [PATCH] usb/redir: avoid dynamic stack allocation (CVE-2021-3527)
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Use autofree heap allocation instead.
+
+Fixes: 4f4321c11ff ("usb: use iovecs in USBPacket")
+Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
+Message-Id: <20210503132915.2335822-3-kraxel@redhat.com>
+
+Upstream-Status: Backport
+https://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986
+CVE: CVE-2021-3527
+Signed-off-by: Chee Yang Lee <chee.yang.lee@intel.com>
+
+---
+ hw/usb/redirect.c | 6 +++---
+ 1 file changed, 3 insertions(+), 3 deletions(-)
+
+diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c
+index 17f06f3417..6a75b0dc4a 100644
+--- a/hw/usb/redirect.c
++++ b/hw/usb/redirect.c
+@@ -620,7 +620,7 @@ static void usbredir_handle_iso_data(USBRedirDevice *dev, USBPacket *p,
+                 .endpoint = ep,
+                 .length = p->iov.size
+             };
+-            uint8_t buf[p->iov.size];
++            g_autofree uint8_t *buf = g_malloc(p->iov.size);
+             /* No id, we look at the ep when receiving a status back */
+             usb_packet_copy(p, buf, p->iov.size);
+             usbredirparser_send_iso_packet(dev->parser, 0, &iso_packet,
+@@ -818,7 +818,7 @@ static void usbredir_handle_bulk_data(USBRedirDevice *dev, USBPacket *p,
+         usbredirparser_send_bulk_packet(dev->parser, p->id,
+                                         &bulk_packet, NULL, 0);
+     } else {
+-        uint8_t buf[size];
++        g_autofree uint8_t *buf = g_malloc(size);
+         usb_packet_copy(p, buf, size);
+         usbredir_log_data(dev, "bulk data out:", buf, size);
+         usbredirparser_send_bulk_packet(dev->parser, p->id,
+@@ -923,7 +923,7 @@ static void usbredir_handle_interrupt_out_data(USBRedirDevice *dev,
+                                                USBPacket *p, uint8_t ep)
+ {
+     struct usb_redir_interrupt_packet_header interrupt_packet;
+-    uint8_t buf[p->iov.size];
++    g_autofree uint8_t *buf = g_malloc(p->iov.size);
+ 
+     DPRINTF("interrupt-out ep %02X len %zd id %"PRIu64"\n", ep,
+             p->iov.size, p->id);
+-- 
+GitLab
+