app-emulation/qemu: fix buffer overflow, CVE-2020-11102

Bug: https://bugs.gentoo.org/716518
Package-Manager: Portage-2.3.96, Repoman-2.3.22
Signed-off-by: Matthias Maier <tamiko@gentoo.org>

2 files changed, 979 insertions, 0 deletions

diff --git a/app-emulation/qemu/files/qemu-4.2.0-CVE-2020-11102.patch b/app-emulation/qemu/files/qemu-4.2.0-CVE-2020-11102.patch
new file mode 100644
index 000000000000..118c81971d83
--- /dev/null
+++ b/app-emulation/qemu/files/qemu-4.2.0-CVE-2020-11102.patch
@@ -0,0 +1,144 @@
+From 8ffb7265af64ec81748335ec8f20e7ab542c3850 Mon Sep 17 00:00:00 2001
+From: Prasad J Pandit <pjp@fedoraproject.org>
+Date: Tue, 24 Mar 2020 22:57:22 +0530
+Subject: [PATCH] net: tulip: check frame size and r/w data length
+
+Tulip network driver while copying tx/rx buffers does not check
+frame size against r/w data length. This may lead to OOB buffer
+access. Add check to avoid it.
+
+Limit iterations over descriptors to avoid potential infinite
+loop issue in tulip_xmit_list_update.
+
+Reported-by: Li Qiang <pangpei.lq@antfin.com>
+Reported-by: Ziming Zhang <ezrakiez@gmail.com>
+Reported-by: Jason Wang <jasowang@redhat.com>
+Tested-by: Li Qiang <liq3ea@gmail.com>
+Reviewed-by: Li Qiang <liq3ea@gmail.com>
+Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
+Signed-off-by: Jason Wang <jasowang@redhat.com>
+---
+ hw/net/tulip.c | 36 +++++++++++++++++++++++++++---------
+ 1 file changed, 27 insertions(+), 9 deletions(-)
+
+diff --git a/hw/net/tulip.c b/hw/net/tulip.c
+index cfac2719d3..1295f51d07 100644
+--- a/hw/net/tulip.c
++++ b/hw/net/tulip.c
+@@ -170,6 +170,10 @@ static void tulip_copy_rx_bytes(TULIPState *s, struct tulip_descriptor *desc)
+         } else {
+             len = s->rx_frame_len;
+         }
++
++        if (s->rx_frame_len + len > sizeof(s->rx_frame)) {
++            return;
++        }
+         pci_dma_write(&s->dev, desc->buf_addr1, s->rx_frame +
+             (s->rx_frame_size - s->rx_frame_len), len);
+         s->rx_frame_len -= len;
+@@ -181,6 +185,10 @@ static void tulip_copy_rx_bytes(TULIPState *s, struct tulip_descriptor *desc)
+         } else {
+             len = s->rx_frame_len;
+         }
++
++        if (s->rx_frame_len + len > sizeof(s->rx_frame)) {
++            return;
++        }
+         pci_dma_write(&s->dev, desc->buf_addr2, s->rx_frame +
+             (s->rx_frame_size - s->rx_frame_len), len);
+         s->rx_frame_len -= len;
+@@ -227,7 +235,8 @@ static ssize_t tulip_receive(TULIPState *s, const uint8_t *buf, size_t size)
+ 
+     trace_tulip_receive(buf, size);
+ 
+-    if (size < 14 || size > 2048 || s->rx_frame_len || tulip_rx_stopped(s)) {
++    if (size < 14 || size > sizeof(s->rx_frame) - 4
++        || s->rx_frame_len || tulip_rx_stopped(s)) {
+         return 0;
+     }
+ 
+@@ -275,7 +284,6 @@ static ssize_t tulip_receive_nc(NetClientState *nc,
+     return tulip_receive(qemu_get_nic_opaque(nc), buf, size);
+ }
+ 
+-
+ static NetClientInfo net_tulip_info = {
+     .type = NET_CLIENT_DRIVER_NIC,
+     .size = sizeof(NICState),
+@@ -558,7 +566,7 @@ static void tulip_tx(TULIPState *s, struct tulip_descriptor *desc)
+         if ((s->csr[6] >> CSR6_OM_SHIFT) & CSR6_OM_MASK) {
+             /* Internal or external Loopback */
+             tulip_receive(s, s->tx_frame, s->tx_frame_len);
+-        } else {
++        } else if (s->tx_frame_len <= sizeof(s->tx_frame)) {
+             qemu_send_packet(qemu_get_queue(s->nic),
+                 s->tx_frame, s->tx_frame_len);
+         }
+@@ -570,23 +578,31 @@ static void tulip_tx(TULIPState *s, struct tulip_descriptor *desc)
+     }
+ }
+ 
+-static void tulip_copy_tx_buffers(TULIPState *s, struct tulip_descriptor *desc)
++static int tulip_copy_tx_buffers(TULIPState *s, struct tulip_descriptor *desc)
+ {
+     int len1 = (desc->control >> TDES1_BUF1_SIZE_SHIFT) & TDES1_BUF1_SIZE_MASK;
+     int len2 = (desc->control >> TDES1_BUF2_SIZE_SHIFT) & TDES1_BUF2_SIZE_MASK;
+ 
++    if (s->tx_frame_len + len1 > sizeof(s->tx_frame)) {
++        return -1;
++    }
+     if (len1) {
+         pci_dma_read(&s->dev, desc->buf_addr1,
+             s->tx_frame + s->tx_frame_len, len1);
+         s->tx_frame_len += len1;
+     }
+ 
++    if (s->tx_frame_len + len2 > sizeof(s->tx_frame)) {
++        return -1;
++    }
+     if (len2) {
+         pci_dma_read(&s->dev, desc->buf_addr2,
+             s->tx_frame + s->tx_frame_len, len2);
+         s->tx_frame_len += len2;
+     }
+     desc->status = (len1 + len2) ? 0 : 0x7fffffff;
++
++    return 0;
+ }
+ 
+ static void tulip_setup_filter_addr(TULIPState *s, uint8_t *buf, int n)
+@@ -651,13 +667,15 @@ static uint32_t tulip_ts(TULIPState *s)
+ 
+ static void tulip_xmit_list_update(TULIPState *s)
+ {
++#define TULIP_DESC_MAX 128
++    uint8_t i = 0;
+     struct tulip_descriptor desc;
+ 
+     if (tulip_ts(s) != CSR5_TS_SUSPENDED) {
+         return;
+     }
+ 
+-    for (;;) {
++    for (i = 0; i < TULIP_DESC_MAX; i++) {
+         tulip_desc_read(s, s->current_tx_desc, &desc);
+         tulip_dump_tx_descriptor(s, &desc);
+ 
+@@ -675,10 +693,10 @@ static void tulip_xmit_list_update(TULIPState *s)
+                 s->tx_frame_len = 0;
+             }
+ 
+-            tulip_copy_tx_buffers(s, &desc);
+-
+-            if (desc.control & TDES1_LS) {
+-                tulip_tx(s, &desc);
++            if (!tulip_copy_tx_buffers(s, &desc)) {
++                if (desc.control & TDES1_LS) {
++                    tulip_tx(s, &desc);
++                }
+             }
+         }
+         tulip_desc_write(s, s->current_tx_desc, &desc);
+-- 
+2.24.1
+
diff --git a/app-emulation/qemu/qemu-4.2.0-r3.ebuild b/app-emulation/qemu/qemu-4.2.0-r3.ebuild
new file mode 100644
index 000000000000..288a676b5811
--- /dev/null
+++ b/app-emulation/qemu/qemu-4.2.0-r3.ebuild
@@ -0,0 +1,835 @@
+# Copyright 1999-2020 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI="7"
+
+PYTHON_COMPAT=( python{3_6,3_7} )
+PYTHON_REQ_USE="ncurses,readline"
+
+PLOCALES="bg de_DE fr_FR hu it tr zh_CN"
+
+FIRMWARE_ABI_VERSION="4.0.0-r50"
+
+inherit eutils linux-info toolchain-funcs multilib python-r1 \
+	udev fcaps readme.gentoo-r1 pax-utils l10n xdg-utils
+
+if [[ ${PV} = *9999* ]]; then
+	EGIT_REPO_URI="https://git.qemu.org/git/qemu.git"
+	EGIT_SUBMODULES=(
+		slirp
+		tests/fp/berkeley-{test,soft}float-3
+		ui/keycodemapdb
+	)
+	inherit git-r3
+	SRC_URI=""
+else
+	SRC_URI="https://download.qemu.org/${P}.tar.xz
+		https://dev.gentoo.org/~tamiko/distfiles/${P}-patches-r1.tar.xz"
+	KEYWORDS="~amd64 ~arm64 ~ppc ~ppc64 ~x86"
+fi
+
+DESCRIPTION="QEMU + Kernel-based Virtual Machine userland tools"
+HOMEPAGE="http://www.qemu.org http://www.linux-kvm.org"
+
+LICENSE="GPL-2 LGPL-2 BSD-2"
+SLOT="0"
+
+IUSE="accessibility +aio alsa bzip2 capstone +caps +curl debug doc
+	+fdt glusterfs gnutls gtk infiniband iscsi jemalloc +jpeg kernel_linux
+	kernel_FreeBSD lzo ncurses nfs nls numa opengl +oss +pin-upstream-blobs
+	plugins +png pulseaudio python rbd sasl +seccomp sdl sdl-image selinux
+	smartcard snappy spice ssh static static-user systemtap tci test usb
+	usbredir vde +vhost-net vhost-user-fs virgl virtfs +vnc vte xattr xen
+	xfs +xkb"
+
+COMMON_TARGETS="aarch64 alpha arm cris hppa i386 m68k microblaze microblazeel
+	mips mips64 mips64el mipsel nios2 or1k ppc ppc64 riscv32 riscv64 s390x
+	sh4 sh4eb sparc sparc64 x86_64 xtensa xtensaeb"
+IUSE_SOFTMMU_TARGETS="${COMMON_TARGETS}
+	lm32 moxie tricore unicore32"
+IUSE_USER_TARGETS="${COMMON_TARGETS}
+	aarch64_be armeb mipsn32 mipsn32el ppc64abi32 ppc64le sparc32plus
+	tilegx"
+
+use_softmmu_targets=$(printf ' qemu_softmmu_targets_%s' ${IUSE_SOFTMMU_TARGETS})
+use_user_targets=$(printf ' qemu_user_targets_%s' ${IUSE_USER_TARGETS})
+IUSE+=" ${use_softmmu_targets} ${use_user_targets}"
+
+RESTRICT="!test? ( test )"
+# Allow no targets to be built so that people can get a tools-only build.
+# Block USE flag configurations known to not work.
+REQUIRED_USE="${PYTHON_REQUIRED_USE}
+	qemu_softmmu_targets_arm? ( fdt )
+	qemu_softmmu_targets_microblaze? ( fdt )
+	qemu_softmmu_targets_mips64el? ( fdt )
+	qemu_softmmu_targets_ppc64? ( fdt )
+	qemu_softmmu_targets_ppc? ( fdt )
+	qemu_softmmu_targets_riscv32? ( fdt )
+	qemu_softmmu_targets_riscv64? ( fdt )
+	static? ( static-user !alsa !gtk !opengl !pulseaudio !plugins !rbd !snappy )
+	static-user? ( !plugins )
+	virtfs? ( xattr )
+	vte? ( gtk )
+	plugins? ( !static !static-user )
+"
+
+# Dependencies required for qemu tools (qemu-nbd, qemu-img, qemu-io, ...)
+# and user/softmmu targets (qemu-*, qemu-system-*).
+#
+# Yep, you need both libcap and libcap-ng since virtfs only uses libcap.
+#
+# The attr lib isn't always linked in (although the USE flag is always
+# respected).  This is because qemu supports using the C library's API
+# when available rather than always using the external library.
+ALL_DEPEND="
+	>=dev-libs/glib-2.0[static-libs(+)]
+	sys-libs/zlib[static-libs(+)]
+	python? ( ${PYTHON_DEPS} )
+	systemtap? ( dev-util/systemtap )
+	xattr? ( sys-apps/attr[static-libs(+)] )"
+
+# Dependencies required for qemu tools (qemu-nbd, qemu-img, qemu-io, ...)
+# softmmu targets (qemu-system-*).
+SOFTMMU_TOOLS_DEPEND="
+	dev-libs/libxml2[static-libs(+)]
+	xkb? ( x11-libs/libxkbcommon[static-libs(+)] )
+	>=x11-libs/pixman-0.28.0[static-libs(+)]
+	accessibility? (
+		app-accessibility/brltty[api]
+		app-accessibility/brltty[static-libs(+)]
+	)
+	aio? ( dev-libs/libaio[static-libs(+)] )
+	alsa? ( >=media-libs/alsa-lib-1.0.13 )
+	bzip2? ( app-arch/bzip2[static-libs(+)] )
+	capstone? ( dev-libs/capstone:= )
+	caps? ( sys-libs/libcap-ng[static-libs(+)] )
+	curl? ( >=net-misc/curl-7.15.4[static-libs(+)] )
+	fdt? ( >=sys-apps/dtc-1.5.0[static-libs(+)] )
+	glusterfs? ( >=sys-cluster/glusterfs-3.4.0[static-libs(+)] )
+	gnutls? (
+		dev-libs/nettle:=[static-libs(+)]
+		>=net-libs/gnutls-3.0:=[static-libs(+)]
+	)
+	gtk? (
+		x11-libs/gtk+:3
+		vte? ( x11-libs/vte:2.91 )
+	)
+	infiniband? (
+		sys-fabric/libibumad:=[static-libs(+)]
+		sys-fabric/libibverbs:=[static-libs(+)]
+		sys-fabric/librdmacm:=[static-libs(+)]
+	)
+	iscsi? ( net-libs/libiscsi )
+	jemalloc? ( dev-libs/jemalloc )
+	jpeg? ( virtual/jpeg:0=[static-libs(+)] )
+	lzo? ( dev-libs/lzo:2[static-libs(+)] )
+	ncurses? (
+		sys-libs/ncurses:0=[unicode]
+		sys-libs/ncurses:0=[static-libs(+)]
+	)
+	nfs? ( >=net-fs/libnfs-1.9.3:=[static-libs(+)] )
+	numa? ( sys-process/numactl[static-libs(+)] )
+	opengl? (
+		virtual/opengl
+		media-libs/libepoxy[static-libs(+)]
+		media-libs/mesa[static-libs(+)]
+		media-libs/mesa[egl,gbm]
+	)
+	png? ( media-libs/libpng:0=[static-libs(+)] )
+	pulseaudio? ( media-sound/pulseaudio )
+	rbd? ( sys-cluster/ceph )
+	sasl? ( dev-libs/cyrus-sasl[static-libs(+)] )
+	sdl? (
+		media-libs/libsdl2[X]
+		media-libs/libsdl2[static-libs(+)]
+	)
+	sdl-image? ( media-libs/sdl2-image[static-libs(+)] )
+	seccomp? ( >=sys-libs/libseccomp-2.1.0[static-libs(+)] )
+	smartcard? ( >=app-emulation/libcacard-2.5.0[static-libs(+)] )
+	snappy? ( app-arch/snappy:= )
+	spice? (
+		>=app-emulation/spice-protocol-0.12.3
+		>=app-emulation/spice-0.12.0[static-libs(+)]
+	)
+	ssh? ( >=net-libs/libssh-0.8.6[static-libs(+)] )
+	usb? ( >=virtual/libusb-1-r2[static-libs(+)] )
+	usbredir? ( >=sys-apps/usbredir-0.6[static-libs(+)] )
+	vde? ( net-misc/vde[static-libs(+)] )
+	virgl? ( media-libs/virglrenderer[static-libs(+)] )
+	virtfs? ( sys-libs/libcap )
+	xen? ( app-emulation/xen-tools:= )
+	xfs? ( sys-fs/xfsprogs[static-libs(+)] )"
+
+X86_FIRMWARE_DEPEND="
+	pin-upstream-blobs? (
+		~sys-firmware/edk2-ovmf-201905[binary]
+		~sys-firmware/ipxe-1.0.0_p20190728[binary]
+		~sys-firmware/seabios-1.12.0[binary,seavgabios]
+		~sys-firmware/sgabios-0.1_pre8[binary]
+	)
+	!pin-upstream-blobs? (
+		sys-firmware/edk2-ovmf
+		sys-firmware/ipxe
+		>=sys-firmware/seabios-1.10.2[seavgabios]
+		sys-firmware/sgabios
+	)"
+PPC64_FIRMWARE_DEPEND="
+	pin-upstream-blobs? (
+		~sys-firmware/seabios-1.12.0[binary,seavgabios]
+	)
+	!pin-upstream-blobs? (
+		>=sys-firmware/seabios-1.10.2[seavgabios]
+	)
+"
+
+BDEPEND="
+	$(python_gen_impl_dep)
+	dev-lang/perl
+	sys-apps/texinfo
+	virtual/pkgconfig
+	doc? ( dev-python/sphinx )
+	gtk? ( nls? ( sys-devel/gettext ) )
+	test? (
+		dev-libs/glib[utils]
+		sys-devel/bc
+	)
+"
+CDEPEND="
+	!static? (
+		${ALL_DEPEND//\[static-libs(+)]}
+		${SOFTMMU_TOOLS_DEPEND//\[static-libs(+)]}
+	)
+	qemu_softmmu_targets_i386? ( ${X86_FIRMWARE_DEPEND} )
+	qemu_softmmu_targets_x86_64? ( ${X86_FIRMWARE_DEPEND} )
+	qemu_softmmu_targets_ppc64? ( ${PPC64_FIRMWARE_DEPEND} )
+"
+DEPEND="${CDEPEND}
+	kernel_linux? ( >=sys-kernel/linux-headers-2.6.35 )
+	static? (
+		${ALL_DEPEND}
+		${SOFTMMU_TOOLS_DEPEND}
+	)
+	static-user? ( ${ALL_DEPEND} )"
+RDEPEND="${CDEPEND}
+	acct-group/kvm
+	selinux? ( sec-policy/selinux-qemu )"
+
+PATCHES=(
+	"${FILESDIR}"/${PN}-2.5.0-cflags.patch
+	"${FILESDIR}"/${PN}-2.5.0-sysmacros.patch
+	"${FILESDIR}"/${PN}-2.11.1-capstone_include_path.patch
+	"${FILESDIR}"/${PN}-4.0.0-sanitize-interp_info.patch
+	"${FILESDIR}"/${PN}-4.0.0-mkdir_systemtap.patch #684902
+	"${FILESDIR}"/${PN}-4.2.0-CVE-2020-11102.patch #716518
+	"${WORKDIR}"/patches
+)
+
+QA_PREBUILT="
+	usr/share/qemu/hppa-firmware.img
+	usr/share/qemu/openbios-ppc
+	usr/share/qemu/openbios-sparc64
+	usr/share/qemu/openbios-sparc32
+	usr/share/qemu/palcode-clipper
+	usr/share/qemu/s390-ccw.img
+	usr/share/qemu/s390-netboot.img
+	usr/share/qemu/u-boot.e500"
+
+QA_WX_LOAD="usr/bin/qemu-i386
+	usr/bin/qemu-x86_64
+	usr/bin/qemu-alpha
+	usr/bin/qemu-arm
+	usr/bin/qemu-cris
+	usr/bin/qemu-m68k
+	usr/bin/qemu-microblaze
+	usr/bin/qemu-microblazeel
+	usr/bin/qemu-mips
+	usr/bin/qemu-mipsel
+	usr/bin/qemu-or1k
+	usr/bin/qemu-ppc
+	usr/bin/qemu-ppc64
+	usr/bin/qemu-ppc64abi32
+	usr/bin/qemu-sh4
+	usr/bin/qemu-sh4eb
+	usr/bin/qemu-sparc
+	usr/bin/qemu-sparc64
+	usr/bin/qemu-armeb
+	usr/bin/qemu-sparc32plus
+	usr/bin/qemu-s390x
+	usr/bin/qemu-unicore32"
+
+DOC_CONTENTS="If you don't have kvm compiled into the kernel, make sure you have the
+kernel module loaded before running kvm. The easiest way to ensure that the
+kernel module is loaded is to load it on boot.
+	For AMD CPUs the module is called 'kvm-amd'.
+	For Intel CPUs the module is called 'kvm-intel'.
+Please review /etc/conf.d/modules for how to load these.
+
+Make sure your user is in the 'kvm' group. Just run
+	$ gpasswd -a <USER> kvm
+then have <USER> re-login.
+
+For brand new installs, the default permissions on /dev/kvm might not let
+you access it.  You can tell udev to reset ownership/perms:
+	$ udevadm trigger -c add /dev/kvm
+
+If you want to register binfmt handlers for qemu user targets:
+For openrc:
+	# rc-update add qemu-binfmt
+For systemd:
+	# ln -s /usr/share/qemu/binfmt.d/qemu.conf /etc/binfmt.d/qemu.conf"
+
+pkg_pretend() {
+	if use kernel_linux && kernel_is lt 2 6 25; then
+		eerror "This version of KVM requres a host kernel of 2.6.25 or higher."
+	elif use kernel_linux; then
+		if ! linux_config_exists; then
+			eerror "Unable to check your kernel for KVM support"
+		else
+			CONFIG_CHECK="~KVM ~TUN ~BRIDGE"
+			ERROR_KVM="You must enable KVM in your kernel to continue"
+			ERROR_KVM_AMD="If you have an AMD CPU, you must enable KVM_AMD in"
+			ERROR_KVM_AMD+=" your kernel configuration."
+			ERROR_KVM_INTEL="If you have an Intel CPU, you must enable"
+			ERROR_KVM_INTEL+=" KVM_INTEL in your kernel configuration."
+			ERROR_TUN="You will need the Universal TUN/TAP driver compiled"
+			ERROR_TUN+=" into your kernel or loaded as a module to use the"
+			ERROR_TUN+=" virtual network device if using -net tap."
+			ERROR_BRIDGE="You will also need support for 802.1d"
+			ERROR_BRIDGE+=" Ethernet Bridging for some network configurations."
+			use vhost-net && CONFIG_CHECK+=" ~VHOST_NET"
+			ERROR_VHOST_NET="You must enable VHOST_NET to have vhost-net"
+			ERROR_VHOST_NET+=" support"
+
+			if use amd64 || use x86 || use amd64-linux || use x86-linux; then
+				if grep -q AuthenticAMD /proc/cpuinfo; then
+					CONFIG_CHECK+=" ~KVM_AMD"
+				elif grep -q GenuineIntel /proc/cpuinfo; then
+					CONFIG_CHECK+=" ~KVM_INTEL"
+				fi
+			fi
+
+			use python && CONFIG_CHECK+=" ~DEBUG_FS"
+			ERROR_DEBUG_FS="debugFS support required for kvm_stat"
+
+			# Now do the actual checks setup above
+			check_extra_config
+		fi
+	fi
+
+	if grep -qs '/usr/bin/qemu-kvm' "${EROOT}"/etc/libvirt/qemu/*.xml; then
+		eerror "The kvm/qemu-kvm wrappers no longer exist, but your libvirt"
+		eerror "instances are still pointing to it.  Please update your"
+		eerror "configs in /etc/libvirt/qemu/ to use the -enable-kvm flag"
+		eerror "and the right system binary (e.g. qemu-system-x86_64)."
+		die "update your virt configs to not use qemu-kvm"
+	fi
+}
+
+# Sanity check to make sure target lists are kept up-to-date.
+check_targets() {
+	local var=$1 mak=$2
+	local detected sorted
+
+	pushd "${S}"/default-configs >/dev/null || die
+
+	# Force C locale until glibc is updated. #564936
+	detected=$(echo $(printf '%s\n' *-${mak}.mak | sed "s:-${mak}.mak::" | LC_COLLATE=C sort -u))
+	sorted=$(echo $(printf '%s\n' ${!var} | LC_COLLATE=C sort -u))
+	if [[ ${sorted} != "${detected}" ]] ; then
+		eerror "The ebuild needs to be kept in sync."
+		eerror "${var}: ${sorted}"
+		eerror "$(printf '%-*s' ${#var} configure): ${detected}"
+		die "sync ${var} to the list of targets"
+	fi
+
+	popd >/dev/null
+}
+
+handle_locales() {
+	# Make sure locale list is kept up-to-date.
+	local detected sorted
+	detected=$(echo $(cd po && printf '%s\n' *.po | grep -v messages.po | sed 's:.po$::' | sort -u))
+	sorted=$(echo $(printf '%s\n' ${PLOCALES} | sort -u))
+	if [[ ${sorted} != "${detected}" ]] ; then
+		eerror "The ebuild needs to be kept in sync."
+		eerror "PLOCALES: ${sorted}"
+		eerror " po/*.po: ${detected}"
+		die "sync PLOCALES"
+	fi
+
+	# Deal with selective install of locales.
+	if use nls ; then
+		# Delete locales the user does not want. #577814
+		rm_loc() { rm po/$1.po || die; }
+		l10n_for_each_disabled_locale_do rm_loc
+	else
+		# Cheap hack to disable gettext .mo generation.
+		rm -f po/*.po
+	fi
+}
+
+src_prepare() {
+	check_targets IUSE_SOFTMMU_TARGETS softmmu
+	check_targets IUSE_USER_TARGETS linux-user
+
+	default
+
+	# Use correct toolchain to fix cross-compiling
+	tc-export AR LD NM OBJCOPY PKG_CONFIG
+	export WINDRES=${CHOST}-windres
+
+	# Verbose builds
+	MAKEOPTS+=" V=1"
+
+	# Run after we've applied all patches.
+	handle_locales
+
+	# Remove bundled copy of libfdt
+	rm -r dtc || die
+}
+
+##
+# configures qemu based on the build directory and the build type
+# we are using.
+#
+qemu_src_configure() {
+	debug-print-function ${FUNCNAME} "$@"
+
+	local buildtype=$1
+	local builddir="${S}/${buildtype}-build"
+
+	mkdir "${builddir}"
+
+	local conf_opts=(
+		--prefix=/usr
+		--sysconfdir=/etc
+		--bindir=/usr/bin
+		--libdir=/usr/$(get_libdir)
+		--datadir=/usr/share
+		--docdir=/usr/share/doc/${PF}/html
+		--mandir=/usr/share/man
+		--with-confsuffix=/qemu
+		--localstatedir=/var
+		--disable-bsd-user
+		--disable-guest-agent
+		--disable-strip
+		--disable-werror
+		# We support gnutls/nettle for crypto operations.  It is possible
+		# to use gcrypt when gnutls/nettle are disabled (but not when they
+		# are enabled), but it's not really worth the hassle.  Disable it
+		# all the time to avoid automatically detecting it. #568856
+		--disable-gcrypt
+		--python="${PYTHON}"
+		--cc="$(tc-getCC)"
+		--cxx="$(tc-getCXX)"
+		--host-cc="$(tc-getBUILD_CC)"
+		$(use_enable debug debug-info)
+		$(use_enable debug debug-tcg)
+		$(use_enable doc docs)
+		$(use_enable plugins)
+		$(use_enable tci tcg-interpreter)
+		$(use_enable xattr attr)
+	)
+
+	# Disable options not used by user targets. This simplifies building
+	# static user targets (USE=static-user) considerably.
+	conf_notuser() {
+		if [[ ${buildtype} == "user" ]] ; then
+			echo "--disable-${2:-$1}"
+		else
+			use_enable "$@"
+		fi
+	}
+	conf_opts+=(
+		--disable-bluez
+		$(conf_notuser accessibility brlapi)
+		$(conf_notuser aio linux-aio)
+		$(conf_notuser bzip2)
+		$(conf_notuser capstone)
+		$(conf_notuser caps cap-ng)
+		$(conf_notuser curl)
+		$(conf_notuser fdt)
+		$(conf_notuser glusterfs)
+		$(conf_notuser gnutls)
+		$(conf_notuser gnutls nettle)
+		$(conf_notuser gtk)
+		$(conf_notuser infiniband rdma)
+		$(conf_notuser iscsi libiscsi)
+		$(conf_notuser jemalloc jemalloc)
+		$(conf_notuser jpeg vnc-jpeg)
+		$(conf_notuser kernel_linux kvm)
+		$(conf_notuser lzo)
+		$(conf_notuser ncurses curses)
+		$(conf_notuser nfs libnfs)
+		$(conf_notuser numa)
+		$(conf_notuser opengl)
+		$(conf_notuser png vnc-png)
+		$(conf_notuser rbd)
+		$(conf_notuser sasl vnc-sasl)
+		$(conf_notuser sdl)
+		$(conf_notuser sdl-image)
+		$(conf_notuser seccomp)
+		$(conf_notuser smartcard)
+		$(conf_notuser snappy)
+		$(conf_notuser spice)
+		$(conf_notuser ssh libssh)
+		$(conf_notuser usb libusb)
+		$(conf_notuser usbredir usb-redir)
+		$(conf_notuser vde)
+		$(conf_notuser vhost-net)
+		$(conf_notuser vhost-user-fs)
+		$(conf_notuser virgl virglrenderer)
+		$(conf_notuser virtfs)
+		$(conf_notuser vnc)
+		$(conf_notuser vte)
+		$(conf_notuser xen)
+		$(conf_notuser xen xen-pci-passthrough)
+		$(conf_notuser xfs xfsctl)
+		$(conf_notuser xkb xkbcommon)
+	)
+
+	if [[ ${buildtype} == "user" ]] ; then
+		conf_opts+=( --disable-libxml2 )
+	else
+		conf_opts+=( --enable-libxml2 )
+	fi
+
+	if [[ ! ${buildtype} == "user" ]] ; then
+		# audio options
+		local audio_opts=(
+			$(usex pulseaudio pa "")
+			$(usev sdl)
+			$(usev alsa)
+			$(usev oss)
+		)
+		conf_opts+=(
+			--audio-drv-list=$(printf "%s," "${audio_opts[@]}")
+		)
+	fi
+
+	case ${buildtype} in
+	user)
+		conf_opts+=(
+			--enable-linux-user
+			--disable-system
+			--disable-blobs
+			--disable-tools
+		)
+		local static_flag="static-user"
+		;;
+	softmmu)
+		conf_opts+=(
+			--disable-linux-user
+			--enable-system
+			--disable-tools
+		)
+		local static_flag="static"
+		;;
+	tools)
+		conf_opts+=(
+			--disable-linux-user
+			--disable-system
+			--disable-blobs
+			--enable-tools
+		)
+		local static_flag="static"
+		;;
+	esac
+
+	local targets="${buildtype}_targets"
+	[[ -n ${targets} ]] && conf_opts+=( --target-list="${!targets}" )
+
+	# Add support for SystemTAP
+	use systemtap && conf_opts+=( --enable-trace-backend=dtrace )
+
+	# We always want to attempt to build with PIE support as it results
+	# in a more secure binary. But it doesn't work with static or if
+	# the current GCC doesn't have PIE support.
+	if use ${static_flag}; then
+		conf_opts+=( --static --disable-pie )
+	else
+		tc-enables-pie && conf_opts+=( --enable-pie )
+	fi
+
+	echo "../configure ${conf_opts[*]}"
+	cd "${builddir}"
+	../configure "${conf_opts[@]}" || die "configure failed"
+
+	# FreeBSD's kernel does not support QEMU assigning/grabbing
+	# host USB devices yet
+	use kernel_FreeBSD && \
+		sed -i -E -e "s|^(HOST_USB=)bsd|\1stub|" "${S}"/config-host.mak
+}
+
+src_configure() {
+	local target
+
+	python_setup
+
+	softmmu_targets= softmmu_bins=()
+	user_targets= user_bins=()
+
+	for target in ${IUSE_SOFTMMU_TARGETS} ; do
+		if use "qemu_softmmu_targets_${target}"; then
+			softmmu_targets+=",${target}-softmmu"
+			softmmu_bins+=( "qemu-system-${target}" )
+		fi
+	done
+
+	for target in ${IUSE_USER_TARGETS} ; do
+		if use "qemu_user_targets_${target}"; then
+			user_targets+=",${target}-linux-user"
+			user_bins+=( "qemu-${target}" )
+		fi
+	done
+
+	softmmu_targets=${softmmu_targets#,}
+	user_targets=${user_targets#,}
+
+	[[ -n ${softmmu_targets} ]] && qemu_src_configure "softmmu"
+	[[ -n ${user_targets}    ]] && qemu_src_configure "user"
+	qemu_src_configure "tools"
+}
+
+src_compile() {
+	if [[ -n ${user_targets} ]]; then
+		cd "${S}/user-build"
+		default
+	fi
+
+	if [[ -n ${softmmu_targets} ]]; then
+		cd "${S}/softmmu-build"
+		default
+	fi
+
+	cd "${S}/tools-build"
+	default
+}
+
+src_test() {
+	if [[ -n ${softmmu_targets} ]]; then
+		cd "${S}/softmmu-build"
+		pax-mark m */qemu-system-* #515550
+		emake -j1 check
+		emake -j1 check-report.html
+	fi
+}
+
+qemu_python_install() {
+	python_domodule "${S}/python/qemu"
+
+	python_doscript "${S}/scripts/kvm/vmxcap"
+	python_doscript "${S}/scripts/qmp/qmp-shell"
+	python_doscript "${S}/scripts/qmp/qemu-ga-client"
+}
+
+# Generate binfmt support files.
+#   - /etc/init.d/qemu-binfmt script which registers the user handlers (openrc)
+#   - /usr/share/qemu/binfmt.d/qemu.conf (for use with systemd-binfmt)
+generate_initd() {
+	local out="${T}/qemu-binfmt"
+	local out_systemd="${T}/qemu.conf"
+	local d="${T}/binfmt.d"
+
+	einfo "Generating qemu binfmt scripts and configuration files"
+
+	# Generate the debian fragments first.
+	mkdir -p "${d}"
+	"${S}"/scripts/qemu-binfmt-conf.sh \
+		--debian \
+		--exportdir "${d}" \
+		--qemu-path "${EPREFIX}/usr/bin" \
+		|| die
+	# Then turn the fragments into a shell script we can source.
+	sed -E -i \
+		-e 's:^([^ ]+) (.*)$:\1="\2":' \
+		"${d}"/* || die
+
+	# Generate the init.d script by assembling the fragments from above.
+	local f qcpu package interpreter magic mask
+	cat "${FILESDIR}"/qemu-binfmt.initd.head >"${out}" || die
+	for f in "${d}"/qemu-* ; do
+		source "${f}"
+
+		# Normalize the cpu logic like we do in the init.d for the native cpu.
+		qcpu=${package#qemu-}
+		case ${qcpu} in
+		arm*)   qcpu="arm";;
+		mips*)  qcpu="mips";;
+		ppc*)   qcpu="ppc";;
+		s390*)  qcpu="s390";;
+		sh*)    qcpu="sh";;
+		sparc*) qcpu="sparc";;
+		esac
+
+		# we use 'printf' here to be portable across 'sh'
+		# implementations: #679168
+		cat <<EOF >>"${out}"
+	if [ "\${cpu}" != "${qcpu}" -a -x "${interpreter}" ] ; then
+		printf '%s\n' ':${package}:M::${magic}:${mask}:${interpreter}:'"\${QEMU_BINFMT_FLAGS}" >/proc/sys/fs/binfmt_misc/register
+	fi
+EOF
+
+		echo ":${package}:M::${magic}:${mask}:${interpreter}:OC" >>"${out_systemd}"
+
+	done
+	cat "${FILESDIR}"/qemu-binfmt.initd.tail >>"${out}" || die
+}
+
+src_install() {
+	if [[ -n ${user_targets} ]]; then
+		cd "${S}/user-build"
+		emake DESTDIR="${ED}" install
+
+		# Install binfmt handler init script for user targets.
+		generate_initd
+		doinitd "${T}/qemu-binfmt"
+
+		# Install binfmt/qemu.conf.
+		insinto "/usr/share/qemu/binfmt.d"
+		doins "${T}/qemu.conf"
+	fi
+
+	if [[ -n ${softmmu_targets} ]]; then
+		cd "${S}/softmmu-build"
+		emake DESTDIR="${ED}" install
+
+		# This might not exist if the test failed. #512010
+		[[ -e check-report.html ]] && dodoc check-report.html
+
+		if use kernel_linux; then
+			udev_newrules "${FILESDIR}"/65-kvm.rules-r1 65-kvm.rules
+		fi
+
+		if use python; then
+			python_foreach_impl qemu_python_install
+		fi
+	fi
+
+	cd "${S}/tools-build"
+	emake DESTDIR="${ED}" install
+
+	# Disable mprotect on the qemu binaries as they use JITs to be fast #459348
+	pushd "${ED}"/usr/bin >/dev/null
+	pax-mark mr "${softmmu_bins[@]}" "${user_bins[@]}" # bug 575594
+	popd >/dev/null
+
+	# Install config file example for qemu-bridge-helper
+	insinto "/etc/qemu"
+	doins "${FILESDIR}/bridge.conf"
+
+	cd "${S}"
+	dodoc Changelog MAINTAINERS docs/specs/pci-ids.txt
+	newdoc pc-bios/README README.pc-bios
+
+	# Disallow stripping of prebuilt firmware files.
+	dostrip -x ${QA_PREBUILT}
+
+	if [[ -n ${softmmu_targets} ]]; then
+		# Remove SeaBIOS since we're using the SeaBIOS packaged one
+		rm "${ED}/usr/share/qemu/bios.bin"
+		rm "${ED}/usr/share/qemu/bios-256k.bin"
+		if use qemu_softmmu_targets_x86_64 || use qemu_softmmu_targets_i386; then
+			dosym ../seabios/bios.bin /usr/share/qemu/bios.bin
+			dosym ../seabios/bios-256k.bin /usr/share/qemu/bios-256k.bin
+		fi
+
+		# Remove vgabios since we're using the seavgabios packaged one
+		rm "${ED}/usr/share/qemu/vgabios.bin"
+		rm "${ED}/usr/share/qemu/vgabios-cirrus.bin"
+		rm "${ED}/usr/share/qemu/vgabios-qxl.bin"
+		rm "${ED}/usr/share/qemu/vgabios-stdvga.bin"
+		rm "${ED}/usr/share/qemu/vgabios-virtio.bin"
+		rm "${ED}/usr/share/qemu/vgabios-vmware.bin"
+		# PPC64 loads vgabios-stdvga
+		if use qemu_softmmu_targets_x86_64 || use qemu_softmmu_targets_i386 || use qemu_softmmu_targets_ppc64; then
+			dosym ../seavgabios/vgabios-isavga.bin /usr/share/qemu/vgabios.bin
+			dosym ../seavgabios/vgabios-cirrus.bin /usr/share/qemu/vgabios-cirrus.bin
+			dosym ../seavgabios/vgabios-qxl.bin /usr/share/qemu/vgabios-qxl.bin
+			dosym ../seavgabios/vgabios-stdvga.bin /usr/share/qemu/vgabios-stdvga.bin
+			dosym ../seavgabios/vgabios-virtio.bin /usr/share/qemu/vgabios-virtio.bin
+			dosym ../seavgabios/vgabios-vmware.bin /usr/share/qemu/vgabios-vmware.bin
+		fi
+
+		# Remove sgabios since we're using the sgabios packaged one
+		rm "${ED}/usr/share/qemu/sgabios.bin"
+		if use qemu_softmmu_targets_x86_64 || use qemu_softmmu_targets_i386; then
+			dosym ../sgabios/sgabios.bin /usr/share/qemu/sgabios.bin
+		fi
+
+		# Remove iPXE since we're using the iPXE packaged one
+		rm "${ED}"/usr/share/qemu/pxe-*.rom
+		if use qemu_softmmu_targets_x86_64 || use qemu_softmmu_targets_i386; then
+			dosym ../ipxe/8086100e.rom /usr/share/qemu/pxe-e1000.rom
+			dosym ../ipxe/80861209.rom /usr/share/qemu/pxe-eepro100.rom
+			dosym ../ipxe/10500940.rom /usr/share/qemu/pxe-ne2k_pci.rom
+			dosym ../ipxe/10222000.rom /usr/share/qemu/pxe-pcnet.rom
+			dosym ../ipxe/10ec8139.rom /usr/share/qemu/pxe-rtl8139.rom
+			dosym ../ipxe/1af41000.rom /usr/share/qemu/pxe-virtio.rom
+		fi
+	fi
+
+	DISABLE_AUTOFORMATTING=true
+	readme.gentoo_create_doc
+}
+
+firmware_abi_change() {
+	local pv
+	for pv in ${REPLACING_VERSIONS}; do
+		if ver_test $pv -lt ${FIRMWARE_ABI_VERSION}; then
+			return 0
+		fi
+	done
+	return 1
+}
+
+pkg_postinst() {
+	if [[ -n ${softmmu_targets} ]] && use kernel_linux; then
+		udev_reload
+	fi
+
+	xdg_icon_cache_update
+
+	[[ -z ${EPREFIX} ]] && [[ -f ${EROOT}/usr/libexec/qemu-bridge-helper ]] && \
+		fcaps cap_net_admin ${EROOT}/usr/libexec/qemu-bridge-helper
+
+	DISABLE_AUTOFORMATTING=true
+	readme.gentoo_print_elog
+
+	if use pin-upstream-blobs && firmware_abi_change; then
+		ewarn "This version of qemu pins new versions of firmware blobs:"
+		ewarn "	$(best_version sys-firmware/edk2-ovmf)"
+		ewarn "	$(best_version sys-firmware/ipxe)"
+		ewarn "	$(best_version sys-firmware/seabios)"
+		ewarn "	$(best_version sys-firmware/sgabios)"
+		ewarn "This might break resume of hibernated guests (started with a different"
+		ewarn "firmware version) and live migration to/from qemu versions with different"
+		ewarn "firmware. Please (cold) restart all running guests. For functional"
+		ewarn "guest migration ensure that all"
+		ewarn "hosts run at least"
+		ewarn "	app-emulation/qemu-${FIRMWARE_ABI_VERSION}."
+	fi
+}
+
+pkg_info() {
+	echo "Using:"
+	echo "  $(best_version app-emulation/spice-protocol)"
+	echo "  $(best_version sys-firmware/edk2-ovmf)"
+	if has_version 'sys-firmware/edk2-ovmf[binary]'; then
+		echo "    USE=binary"
+	else
+		echo "    USE=''"
+	fi
+	echo "  $(best_version sys-firmware/ipxe)"
+	echo "  $(best_version sys-firmware/seabios)"
+	if has_version 'sys-firmware/seabios[binary]'; then
+		echo "    USE=binary"
+	else
+		echo "    USE=''"
+	fi
+	echo "  $(best_version sys-firmware/sgabios)"
+}
+
+pkg_postrm() {
+	xdg_icon_cache_update
+}