Unlike other pseudo-encodings these don't break gtk-vnc
because older versions don't suport the extended desktop
resize extension in the first place.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20210125104041.495274-3-kraxel@redhat.com>
This reverts commit 9e1632ad07.
Older gtk-vnc versions can't deal with non-incremental update
requests sending pseudo-encodings, so trying to send full server
state (including desktop size, cursor etc. which is done using
pseudo-encodings) doesn't fly. Return to old behavior to send
those only for new connects and when changes happen.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20210125104041.495274-2-kraxel@redhat.com>
Use qemu_opts_parse_noisily now that HMP does not call
vnc_parse anymore.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Message-Id: <20210120144235.345983-4-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The extended desktop resize encoding adds support for (a) clients
sending resize requests to the server, and (b) multihead support.
This patch implements (a). All resize requests are rejected by qemu.
Qemu can't resize the framebuffer on its own, this is in the hands of
the guest, so all qemu can do is forward the request to the guest.
Should the guest actually resize the framebuffer we can notify the vnc
client later with a separate message.
This requires support in the display device. Works with virtio-gpu.
https://github.com/rfbproto/rfbproto/blob/master/rfbproto.rst#extendeddesktopsize-pseudo-encoding
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20210112134120.2031837-4-kraxel@redhat.com
qemu sends various state info like current cursor shape to newly connected
clients in response to a set_encoding message. This is not correct according
to the rfb spec. Send that information in response to a full (incremental=0)
framebuffer update request instead. Also send the resize information
unconditionally, not only in case of an actual server-side change.
This makes the qemu vnc server conform to the spec and allows clients to
request the complete vnc server state without reconnect.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20210112134120.2031837-3-kraxel@redhat.com
Move the check whenever a cursor exists into the vnc_cursor_define()
function so callers don't have to do it.
Suggested-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20210112134120.2031837-2-kraxel@redhat.com
The "XVP" (Xen VNC Proxy) extension defines a mechanism for a VNC client
to issue power control requests to trigger graceful shutdown, reboot, or
hard reset.
This option is not enabled by default, since we cannot assume that users
with VNC access implicitly have administrator access to the guest OS.
Thus is it enabled with a boolean "power-control" option e.g.
-vnc :1,power-control=on
While, QEMU can easily support shutdown and reset, there's no easy way
to wire up reboot support at this time. In theory it could be done by
issuing a shutdown, followed by a reset, but there's no convenient
wiring for such a pairing in QEMU. It also isn't possible to have the
VNC server directly talk to QEMU guest agent, since the agent chardev is
typically owned by an external mgmt app.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
[ kraxel: rebase to master ]
[ kraxel: add missing break ]
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
In vnc_display_open(), if tls-creds is enabled, do object_ref(object
ref 1->2) for tls-creds. While in vnc_display_close(), object_unparent
sets object ref to 1(2->1) and unparent the object for root.
Problem:
1. the object can not be found from the objects_root, while the object
is not finalized.
2. the qemu_opts of tls-creds(id: creds0) is not deleted, so new tls
object with the same id(creds0) can not be delete & add.
Signed-off-by: Zihao Chang <changzihao1@huawei.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210111131911.805-1-changzihao1@huawei.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Anywhere we create a list of just one item or by prepending items
(typically because order doesn't matter), we can use
QAPI_LIST_PREPEND(). But places where we must keep the list in order
by appending remain open-coded until later patches.
Note that as a side effect, this also performs a cleanup of two minor
issues in qga/commands-posix.c: the old code was performing
new = g_malloc0(sizeof(*ret));
which 1) is confusing because you have to verify whether 'new' and
'ret' are variables with the same type, and 2) would conflict with C++
compilation (not an actual problem for this file, but makes
copy-and-paste harder).
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201113011340.463563-5-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
[Straightforward conflicts due to commit a8aa94b5f8 "qga: update
schema for guest-get-disks 'dependents' field" and commit a10b453a52
"target/mips: Move mips_cpu_add_definition() from helper.c to cpu.c"
resolved. Commit message tweaked.]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
vnc_write() should be locked after the RFB protocol is initialized.
Fixes: 0c426e4534 ("vnc: Add support for color map")
Cc: qemu-stable@nongnu.org
Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Peng Liang <liangpeng10@huawei.com>
Message-id: 20201116141338.148911-1-liangpeng10@huawei.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
There is a new vnc extension for cursors with an alpha channel. Use
it if supported by the vnc client, prefer it over the "rich cursor"
extension which supports only a bitmask for transparency.
This is a visible improvement especially on modern desktops which
actually use the alpha channel when defining cursors.
https://github.com/rfbproto/rfbproto/blob/master/rfbproto.rst#cursor-with-alpha-pseudo-encoding
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Tested-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20201208115737.18581-7-kraxel@redhat.com
vnc stopped using the copyrect pseudo encoding in 2017, in commit
50628d3479 ("cirrus/vnc: zap bitblit support from console code.")
So we can drop the now unused copyrect feature bit.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20201208115737.18581-5-kraxel@redhat.com
When we connect to vnc by websocket channel, and disconnect
(maybe by some network exception) before handshake,
qemu will left CLOSE_WAIT socket and never close it
After 04d2529da2 ("ui: convert VNC server to use QIOChannelSocket")
and dd154c4d9f ("io: fix handling of EOF / error conditions in websock GSource"),
the vnc call qio_channel_add_watch only care about G_IO_IN,
but mising G_IO_HUP and G_IO_ERR.
When the websocket channel get EOF or error, it cannot callback,
because the caller ignore the event, that leads to resource leak
We need handle G_IO_HUP and G_IO_ERR event, then cleanup the channel
Fixes: 04d2529da2 ("ui: convert VNC server to use QIOChannelSocket")
Fixes: dd154c4d9f ("io: fix handling of EOF / error conditions in websock GSource")
Cc: qemu-stable@nongnu.org
Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Message-id: 20201029032241.11040-1-dinghui@sangfor.com.cn
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Pass &error_abort instead of NULL where the returned value is
dereferenced or asserted to be non-null. Drop a now redundant
assertion.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-24-armbru@redhat.com>
vnc_display_print_local_addr() leaks the Error object when
qio_channel_socket_get_local_address() fails. Seems unlikely. Called
when we create a VNC display with vnc_display_open(). Plug the leak
by passing NULL to ignore the error.
Cc: Daniel P. Berrange <berrange@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200630090351.1247703-12-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Receiving the error in a local variable only to free it is less clear
(and also less efficient) than passing NULL. Clean up.
Cc: Daniel P. Berrange <berrange@redhat.com>
Cc: Jerome Forissier <jerome@forissier.org>
CC: Greg Kurz <groug@kaod.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200630090351.1247703-4-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The buffer is the captured input to pass to backends.
As we should not modify it, mark the argument const.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200505132603.8575-3-f4bug@amsat.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
In my investigation, ZRLE always compresses better than ZLIB so
prioritize ZRLE over ZLIB, even if the client hints that ZLIB is
preferred.
zlib buffer is always reset in zrle_compress_data(), so using offset to
calculate next_out and avail_out is useless.
Signed-off-by: Cameron Esfahani <dirty@apple.com>
Message-Id: <b5d129895d08a90d0a2a6183b95875bacfa998b8.1579582674.git.dirty@apple.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This reverts commit de3f7de7f4.
Remove VNC optimization to reencode framebuffer update as raw if it's
smaller than the default encoding.
QEMU's implementation was naive and didn't account for the ZLIB z_stream
mutating with each compression. Because of the mutation, simply
resetting the output buffer's offset wasn't sufficient to "rewind" the
operation. The mutated z_stream would generate future zlib blocks which
referred to symbols in past blocks which weren't sent. This would lead
to artifacting.
Considering that ZRLE is never larger than raw and even though ZLIB can
occasionally be fractionally larger than raw, the overhead of
implementing this optimization correctly isn't worth it.
Signed-off-by: Cameron Esfahani <dirty@apple.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
We don't need Error **, as all callers pass local Error object, which
isn't used after the call, or NULL. Use Error * instead.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191205174635.18758-6-vsementsov@virtuozzo.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Currently when qemu receives a vnc connect, it creates a 'VncState' to
represent this connection. In 'vnc_worker_thread_loop' it creates a
local 'VncState'. The connection 'VcnState' and local 'VncState' exchange
data in 'vnc_async_encoding_start' and 'vnc_async_encoding_end'.
In 'zrle_compress_data' it calls 'deflateInit2' to allocate the libz library
opaque data. The 'VncState' used in 'zrle_compress_data' is the local
'VncState'. In 'vnc_zrle_clear' it calls 'deflateEnd' to free the libz
library opaque data. The 'VncState' used in 'vnc_zrle_clear' is the connection
'VncState'. In currently implementation there will be a memory leak when the
vnc disconnect. Following is the asan output backtrack:
Direct leak of 29760 byte(s) in 5 object(s) allocated from:
0 0xffffa67ef3c3 in __interceptor_calloc (/lib64/libasan.so.4+0xd33c3)
1 0xffffa65071cb in g_malloc0 (/lib64/libglib-2.0.so.0+0x571cb)
2 0xffffa5e968f7 in deflateInit2_ (/lib64/libz.so.1+0x78f7)
3 0xaaaacec58613 in zrle_compress_data ui/vnc-enc-zrle.c:87
4 0xaaaacec58613 in zrle_send_framebuffer_update ui/vnc-enc-zrle.c:344
5 0xaaaacec34e77 in vnc_send_framebuffer_update ui/vnc.c:919
6 0xaaaacec5e023 in vnc_worker_thread_loop ui/vnc-jobs.c:271
7 0xaaaacec5e5e7 in vnc_worker_thread ui/vnc-jobs.c:340
8 0xaaaacee4d3c3 in qemu_thread_start util/qemu-thread-posix.c:502
9 0xffffa544e8bb in start_thread (/lib64/libpthread.so.0+0x78bb)
10 0xffffa53965cb in thread_start (/lib64/libc.so.6+0xd55cb)
This is because the opaque allocated in 'deflateInit2' is not freed in
'deflateEnd'. The reason is that the 'deflateEnd' calls 'deflateStateCheck'
and in the latter will check whether 's->strm != strm'(libz's data structure).
This check will be true so in 'deflateEnd' it just return 'Z_STREAM_ERROR' and
not free the data allocated in 'deflateInit2'.
The reason this happens is that the 'VncState' contains the whole 'VncZrle',
so when calling 'deflateInit2', the 's->strm' will be the local address.
So 's->strm != strm' will be true.
To fix this issue, we need to make 'zrle' of 'VncState' to be a pointer.
Then the connection 'VncState' and local 'VncState' exchange mechanism will
work as expection. The 'tight' of 'VncState' has the same issue, let's also turn
it to a pointer.
Reported-by: Ying Fang <fangying1@huawei.com>
Signed-off-by: Li Qiang <liq3ea@163.com>
Message-id: 20190831153922.121308-1-liq3ea@163.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Audio functions no longer access glob_audio_state, instead they get an
AudioState as a parameter. This is required in order to support
multiple backends.
glob_audio_state is also gone, and replaced with a tailq so we can store
more than one states.
Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Message-id: 67aef54f9e729a7160fe95c465351115e392164b.1566168923.git.DirtY.iCE.hu@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
In my "build everything" tree, changing qemu/main-loop.h triggers a
recompile of some 5600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h). It includes block/aio.h,
which in turn includes qemu/event_notifier.h, qemu/notify.h,
qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h,
qemu/thread.h, qemu/timer.h, and a few more.
Include qemu/main-loop.h only where it's needed. Touching it now
recompiles only some 1700 objects. For block/aio.h and
qemu/event_notifier.h, these numbers drop from 5600 to 2800. For the
others, they shrink only slightly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-21-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
docs/devel/tracing.txt explains "since many source files include
trace.h, [the generated trace.h use] a minimum of types and other
header files included to keep the namespace clean and compile times
and dependencies down."
Commit 4815185902 "trace: Add per-vCPU tracing states for events with
the 'vcpu' property" made them all include qom/cpu.h via
control-internal.h. qom/cpu.h in turn includes about thirty headers.
Ouch.
Per-vCPU tracing is currently not supported in sub-directories'
trace-events. In other words, qom/cpu.h can only be used in
trace-root.h, not in any trace.h.
Split trace/control-vcpu.h off trace/control.h and
trace/control-internal.h. Have the generated trace.h include
trace/control.h (which no longer includes qom/cpu.h), and trace-root.h
include trace/control-vcpu.h (which includes it).
The resulting improvement is a bit disappointing: in my "build
everything" tree, some 1100 out of 6600 objects (not counting tests
and objects that don't depend on qemu/osdep.h) depend on a trace.h,
and about 600 of them no longer depend on qom/cpu.h. But more than
1300 others depend on trace-root.h. More work is clearly needed.
Left for another day.
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-8-armbru@redhat.com>
Use a better interface for random numbers than rand().
Fail gracefully if for some reason we cannot use the crypto system.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
There were 3 copies of this code, one of which used the wrong
data size for the failure indicator.
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
I had to include an enum for audio sampling formats into qapi, but that
meant duplicating the audfmt_e enum. This patch replaces audfmt_e and
associated values with the qapi generated AudioFormat enum.
This patch is mostly a search-and-replace, except for switches where the
qapi generated AUDIO_FORMAT_MAX caused problems.
Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: 01251b2758a1679c66842120b77c0fb46d7d0eaf.1552083282.git.DirtY.iCE.hu@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The VNC server has historically had support for ACLs to check both the
SASL username and the TLS x509 distinguished name. The VNC server was
responsible for creating the initial ACL, and the client app was then
responsible for populating it with rules using the HMP 'acl_add' command.
This is not satisfactory for a variety of reasons. There is no way to
populate the ACLs from the command line, users are forced to use the
HMP. With multiple network services all supporting TLS and ACLs now, it
is desirable to be able to define a single ACL that is referenced by all
services.
To address these limitations, two new options are added to the VNC
server CLI. The 'tls-authz' option takes the ID of a QAuthZ object to
use for checking TLS x509 distinguished names, and the 'sasl-authz'
option takes the ID of another object to use for checking SASL usernames.
In this example, we setup two authorization rules. The first allows any
client with a certificate issued by the 'RedHat' organization in the
'London' locality. The second ACL allows clients with either the
'joe@REDHAT.COM' or 'fred@REDHAT.COM' kerberos usernames. Both checks
must pass for the user to be allowed.
$QEMU -object tls-creds-x509,id=tls0,dir=/home/berrange/qemutls,\
endpoint=server,verify-peer=yes \
-object authz-simple,id=authz0,policy=deny,\
rules.0.match=O=RedHat,,L=London,rules.0.policy=allow \
-object authz-simple,id=authz1,policy=deny,\
rules.0.match=fred@REDHAT.COM,rules.0.policy=allow \
rules.0.match=joe@REDHAT.COM,rules.0.policy=allow \
-vnc 0.0.0.0:1,tls-creds=tls0,tls-authz=authz0,
sasl,sasl-authz=authz1 \
...other QEMU args...
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20190227145755.26556-2-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
vnc aborts display update jobs on video mode switches and page flips.
That can cause vnc update stalls in case an unfinished vnc job gets
aborted. The vnc client will never receive the requested update then.
Fix that by copying the state from job_update back to update in that
case.
Reports complain about stalls with two or more clients being connected
at the same time, on some but not all connections. I suspect it can
also happen with a single connection, multiple connections only make
this more much likely to happen.
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1662260
Reported-by: Ying Fang <fangying1@huawei.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ying Fang <fangying1@huawei.com>
Message-id: 20190305130930.24516-1-kraxel@redhat.com
The 'qemu_acl' type was a previous non-QOM based attempt to provide an
authorization facility in QEMU. Because it is non-QOM based it cannot be
created via the command line and requires special monitor commands to
manipulate it.
The new QAuthZ subclasses provide a superset of the functionality in
qemu_acl, so the latter can now be deleted. The HMP 'acl_*' monitor
commands are converted to use the new QAuthZSimple data type instead
in order to provide temporary backwards compatibility.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Having to include qapi-events.h just for QAPIEvent is suboptimal, but
quite tolerable now. It'll become problematic when we have events
conditional on the target, because then qapi-events.h won't be usable
from target-independent code anymore. Avoid that by generating it
into separate files.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-6-armbru@redhat.com>
It is possible that the modifier state on keyup is different from the
modifier state on keydown. In that case the keycode lookup can end up
with different keys in case multiple keysym -> keycode mappings exist,
because it picks the mapping depending on modifier state.
To fix that change the lookup logic for keyup events. Instead of
looking at the modifier state check the key state and prefer a keycodes
where the key is in "down" state right now.
Fixes: abb4f2c965 keymap: consider modifier state when picking a mapping
Buglink: https://bugs.launchpad.net/bugs/1738283
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1658676
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190122092814.14919-9-kraxel@redhat.com
Pass the keyboard state tracker handle down to keysym2scancode(),
so the code can fully inspect the keyboard state as needed. No
functional change.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190122092814.14919-8-kraxel@redhat.com
Use the new keyboard state tracked for vnc. Allows to drop the
vnc-specific modifier state tracking code.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190122092814.14919-7-kraxel@redhat.com
When size and format of the display surface stays the same we can just
tag the guest display as dirty and be done with it.
There is no need need to resize the vnc server display or to touch the
vnc client dirty bits. On the next refresh cycle
vnc_refresh_server_surface() will check for actual display content
changes and update the client dirty bits as needed.
The desktop resize and framebuffer format notifications to the vnc
client will be skipped too.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190116101049.8929-1-kraxel@redhat.com
Most files that have TABs only contain a handful of them. Change
them to spaces so that we don't confuse people.
disas, standard-headers, linux-headers and libdecnumber are imported
from other projects and probably should be exempted from the check.
Outside those, after this patch the following files still contain both
8-space and TAB sequences at the beginning of the line. Many of them
have a majority of TABs, or were initially committed with all tabs.
bsd-user/i386/target_syscall.h
bsd-user/x86_64/target_syscall.h
crypto/aes.c
hw/audio/fmopl.c
hw/audio/fmopl.h
hw/block/tc58128.c
hw/display/cirrus_vga.c
hw/display/xenfb.c
hw/dma/etraxfs_dma.c
hw/intc/sh_intc.c
hw/misc/mst_fpga.c
hw/net/pcnet.c
hw/sh4/sh7750.c
hw/timer/m48t59.c
hw/timer/sh_timer.c
include/crypto/aes.h
include/disas/bfd.h
include/hw/sh4/sh.h
libdecnumber/decNumber.c
linux-headers/asm-generic/unistd.h
linux-headers/linux/kvm.h
linux-user/alpha/target_syscall.h
linux-user/arm/nwfpe/double_cpdo.c
linux-user/arm/nwfpe/fpa11_cpdt.c
linux-user/arm/nwfpe/fpa11_cprt.c
linux-user/arm/nwfpe/fpa11.h
linux-user/flat.h
linux-user/flatload.c
linux-user/i386/target_syscall.h
linux-user/ppc/target_syscall.h
linux-user/sparc/target_syscall.h
linux-user/syscall.c
linux-user/syscall_defs.h
linux-user/x86_64/target_syscall.h
slirp/cksum.c
slirp/if.c
slirp/ip.h
slirp/ip_icmp.c
slirp/ip_icmp.h
slirp/ip_input.c
slirp/ip_output.c
slirp/mbuf.c
slirp/misc.c
slirp/sbuf.c
slirp/socket.c
slirp/socket.h
slirp/tcp_input.c
slirp/tcpip.h
slirp/tcp_output.c
slirp/tcp_subr.c
slirp/tcp_timer.c
slirp/tftp.c
slirp/udp.c
slirp/udp.h
target/cris/cpu.h
target/cris/mmu.c
target/cris/op_helper.c
target/sh4/helper.c
target/sh4/op_helper.c
target/sh4/translate.c
tcg/sparc/tcg-target.inc.c
tests/tcg/cris/check_addo.c
tests/tcg/cris/check_moveq.c
tests/tcg/cris/check_swap.c
tests/tcg/multiarch/test-mmap.c
ui/vnc-enc-hextile-template.h
ui/vnc-enc-zywrle.h
util/envlist.c
util/readline.c
The following have only TABs:
bsd-user/i386/target_signal.h
bsd-user/sparc64/target_signal.h
bsd-user/sparc64/target_syscall.h
bsd-user/sparc/target_signal.h
bsd-user/sparc/target_syscall.h
bsd-user/x86_64/target_signal.h
crypto/desrfb.c
hw/audio/intel-hda-defs.h
hw/core/uboot_image.h
hw/sh4/sh7750_regnames.c
hw/sh4/sh7750_regs.h
include/hw/cris/etraxfs_dma.h
linux-user/alpha/termbits.h
linux-user/arm/nwfpe/fpopcode.h
linux-user/arm/nwfpe/fpsr.h
linux-user/arm/syscall_nr.h
linux-user/arm/target_signal.h
linux-user/cris/target_signal.h
linux-user/i386/target_signal.h
linux-user/linux_loop.h
linux-user/m68k/target_signal.h
linux-user/microblaze/target_signal.h
linux-user/mips64/target_signal.h
linux-user/mips/target_signal.h
linux-user/mips/target_syscall.h
linux-user/mips/termbits.h
linux-user/ppc/target_signal.h
linux-user/sh4/target_signal.h
linux-user/sh4/termbits.h
linux-user/sparc64/target_syscall.h
linux-user/sparc/target_signal.h
linux-user/x86_64/target_signal.h
linux-user/x86_64/termbits.h
pc-bios/optionrom/optionrom.h
slirp/mbuf.h
slirp/misc.h
slirp/sbuf.h
slirp/tcp.h
slirp/tcp_timer.h
slirp/tcp_var.h
target/i386/svm.h
target/sparc/asi.h
target/xtensa/core-dc232b/xtensa-modules.inc.c
target/xtensa/core-dc233c/xtensa-modules.inc.c
target/xtensa/core-de212/core-isa.h
target/xtensa/core-de212/xtensa-modules.inc.c
target/xtensa/core-fsf/xtensa-modules.inc.c
target/xtensa/core-sample_controller/core-isa.h
target/xtensa/core-sample_controller/xtensa-modules.inc.c
target/xtensa/core-test_kc705_be/core-isa.h
target/xtensa/core-test_kc705_be/xtensa-modules.inc.c
tests/tcg/cris/check_abs.c
tests/tcg/cris/check_addc.c
tests/tcg/cris/check_addcm.c
tests/tcg/cris/check_addoq.c
tests/tcg/cris/check_bound.c
tests/tcg/cris/check_ftag.c
tests/tcg/cris/check_int64.c
tests/tcg/cris/check_lz.c
tests/tcg/cris/check_openpf5.c
tests/tcg/cris/check_sigalrm.c
tests/tcg/cris/crisutils.h
tests/tcg/cris/sys.c
tests/tcg/i386/test-i386-ssse3.c
ui/vgafont.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20181213223737.11793-3-pbonzini@redhat.com>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Eric Blake <eblake@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Stefan Markovic <smarkovic@wavecomp.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Calling error_report() in a function that takes an Error ** argument
is suspicious. vnc_init_func() does that, and then fails without
setting an error. Its caller main(), via qemu_opts_foreach(), is fine
with it, but clean it up anyway.
While there, drop a "Failed to start VNC server: " error message
prefix that doesn't really add value.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20181017082702.5581-28-armbru@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
VNC server is calling sasl_server_init() during startup of QEMU, even
if SASL auth has not been enabled.
This may create undesirable warnings like "Could not find keytab file:
/etc/qemu/krb5.tab" when the user didn't configure SASL on host and
started VNC server.
Instead, only initialize SASL when needed. Note that HMP/QMP "change
vnc" calls vnc_display_open() again, which will initialize SASL if
needed.
Fix assignment in if condition, while touching this code.
Related to:
https://bugzilla.redhat.com/show_bug.cgi?id=1609327
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180907063634.359-1-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The generated qapi_event_send_FOO() take an Error ** argument. They
can't actually fail, because all they do with the argument is passing it
to functions that can't fail: the QObject output visitor, and the
@qmp_emit callback, which is either monitor_qapi_event_queue() or
event_test_emit().
Drop the argument, and pass &error_abort to the QObject output visitor
and @qmp_emit instead.
Suggested-by: Eric Blake <eblake@redhat.com>
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-4-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message rewritten, update to qapi-code-gen.txt corrected]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The 'tls-creds' option accepts the name of a TLS credentials
object. This replaced the usage of 'tls', 'x509' and 'x509verify'
options in 2.5.0. These deprecated options were grandfathered in
when the deprecation policy was introduded in 2.10.0, so can now
finally be removed.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180725092751.21767-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Set magic cookie on initialization. Clear on cleanup. Sprinkle a bunch
of assert()s checking the cookie, to verify the pointer is valid.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20180507102254.12107-1-kraxel@redhat.com
When vnc_client_read() return value is -1
vs is not valid any more.
Fixes: d49b87f0d1
Reported-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180420084820.3873-1-kraxel@redhat.com
Secondary displays in multihead setups are allowed to have a NULL
DisplaySurface. Typically user interfaces handle this by hiding the
window which shows the display in question.
This isn't an option for vnc though because it simply hasn't a concept
of windows or outputs. So handle the situation by showing a placeholder
DisplaySurface instead. Also check in console_select whenever a surface
is preset in the first place before requesting an update.
This fixes a segfault which can be triggered by switching to an unused
display (via vtrl-alt-<nr>) in a multihead setup, for example using
-device virtio-vga,max_outputs=2.
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 20180308161803.6152-1-kraxel@redhat.com
Move qapi-schema.json to qapi/, so it's next to its modules, and all
files get generated to qapi/, not just the ones generated for modules.
Consistently name the generated files qapi-MODULE.EXT:
qmp-commands.[ch] become qapi-commands.[ch], qapi-event.[ch] become
qapi-events.[ch], and qmp-introspect.[ch] become qapi-introspect.[ch].
This gets rid of the temporary hacks in scripts/qapi/commands.py,
scripts/qapi/events.py, and scripts/qapi/common.py.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-28-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
[eblake: Fix trailing dot in tpm.c, undo temporary hack for OSX toolchain]
Signed-off-by: Eric Blake <eblake@redhat.com>
In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.
The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h. Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.
To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects. The next commit will
improve it further.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-24-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
Pass the modifier state to the keymap lookup function. In case multiple
keysym -> keycode mappings exist look at the modifier state and prefer
the mapping where the modifier state matches.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180222070513.8740-6-kraxel@redhat.com
The 'vs->as.freq' value is a signed integer, which is read from an
unsigned 32-bit int field on the wire. There is thus a risk of overflow
on 32-bit platforms. Move the frequency limit checking to be done at
time of read before casting to a signed integer.
Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180205114938.15784-4-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
For very large framebuffers, it is theoretically possible for the result
of 'vs->throttle_output_offset * VNC_THROTTLE_OUTPUT_LIMIT_SCALE' to
exceed the size of a 32-bit int. For this to happen in practice, the
video RAM would have to be set to a large enough value, which is not
likely today. None the less we can be paranoid against future growth by
using division instead of multiplication when checking the limits.
Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180205114938.15784-2-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
On one of our client's node, due to trying to read from closed ioc,
a segmentation fault occured. Corresponding backtrace:
0 object_get_class (obj=obj@entry=0x0)
1 qio_channel_readv_full (ioc=0x0, iov=0x7ffe55277180 ...
2 qio_channel_read (ioc=<optimized out> ...
3 vnc_client_read_buf (vs=vs@entry=0x55625f3c6000, ...
4 vnc_client_read_plain (vs=0x55625f3c6000)
5 vnc_client_read (vs=0x55625f3c6000)
6 vnc_client_io (ioc=<optimized out>, condition=G_IO_IN, ...
7 g_main_dispatch (context=0x556251568a50)
8 g_main_context_dispatch (context=context@entry=0x556251568a50)
9 glib_pollfds_poll ()
10 os_host_main_loop_wait (timeout=<optimized out>)
11 main_loop_wait (nonblocking=nonblocking@entry=0)
12 main_loop () at vl.c:1909
13 main (argc=<optimized out>, argv=<optimized out>, ...
Having analyzed the coredump, I understood that the reason is that
ioc_tag is reset on vnc_disconnect_start and ioc is cleaned
in vnc_disconnect_finish. Between these two events due to some
reasons the ioc_tag was set again and after vnc_disconnect_finish
the handler is running with freed ioc,
which led to the segmentation fault.
The patch checks vs->disconnecting in places where we call
qio_channel_add_watch and resets handler if disconnecting == TRUE
to prevent such an occurrence.
Signed-off-by: Klim Kireev <klim.kireev@virtuozzo.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180207094844.21402-1-klim.kireev@virtuozzo.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
vnc_listen_io() does not own the reference on the 'cioc' parameter is it
passed, so should not be unref'ing it.
Fixes: 13e1d0e71e
Reported-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20180215102602.10864-1-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
qemu-common.h includes qemu/option.h, but most places that include the
former don't actually need the latter. Drop the include, and add it
to the places that actually need it.
While there, drop superfluous includes of both headers, and
separate #include from file comment with a blank line.
This cleanup makes the number of objects depending on qemu/option.h
drop from 4545 (out of 4743) to 284 in my "build everything" tree.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-20-armbru@redhat.com>
[Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
qapi/qmp/types.h is a convenience header to include a number of
qapi/qmp/ headers. Since we rarely need all of the headers
qapi/qmp/types.h includes, we bypass it most of the time. Most of the
places that use it don't need all the headers, either.
Include the necessary headers directly, and drop qapi/qmp/types.h.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-9-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-6-armbru@redhat.com>
This cleanup makes the number of objects depending on qapi/error.h
drop from 1910 (out of 4743) to 1612 in my "build everything" tree.
While there, separate #include from file comment with a blank line,
and drop a useless comment on why qemu/osdep.h is included first.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-5-armbru@redhat.com>
[Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
The VNC server already has the ability to listen on multiple sockets.
Converting it to use the QIONetListener APIs though, will reduce the
amount of code in the VNC server and improve the clarity of what is
left.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20180201164514.10330-1-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Pixman returns a signed int for the image width/height, but the VNC
protocol only permits a unsigned int16. Effective framebuffer size
is determined by the guest, limited by the video RAM size, so the
dimensions are unlikely to exceed the range of an unsigned int16,
but this is not currently validated.
With the current use of 'int' for client width/height, the calculation
of offsets in vnc_update_throttle_offset() suffers from integer size
promotion and sign extension, causing coverity warnings
*** CID 1385147: Integer handling issues (SIGN_EXTENSION)
/ui/vnc.c: 979 in vnc_update_throttle_offset()
973 * than that the client would already suffering awful audio
974 * glitches, so dropping samples is no worse really).
975 */
976 static void vnc_update_throttle_offset(VncState *vs)
977 {
978 size_t offset =
>>> CID 1385147: Integer handling issues (SIGN_EXTENSION)
>>> Suspicious implicit sign extension:
"vs->client_pf.bytes_per_pixel" with type "unsigned char" (8 bits,
unsigned) is promoted in "vs->client_width * vs->client_height *
vs->client_pf.bytes_per_pixel" to type "int" (32 bits, signed), then
sign-extended to type "unsigned long" (64 bits, unsigned). If
"vs->client_width * vs->client_height * vs->client_pf.bytes_per_pixel"
is greater than 0x7FFFFFFF, the upper bits of the result will all be 1.
979 vs->client_width * vs->client_height * vs->client_pf.bytes_per_pixel;
Change client_width / client_height to be a size_t to avoid sign
extension and integer promotion. Then validate that dimensions are in
range wrt the RFB protocol u16 limits.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20180118155254.17053-1-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
While the QIOChannel APIs for reading/writing data return ssize_t, with negative
value indicating an error, the VNC code passes this return value through the
vnc_client_io_error() method. This detects the error condition, disconnects the
client and returns 0 to indicate error. Thus all the VNC helper methods should
return size_t (unsigned), and misleading comments which refer to the possibility
of negative return values need fixing.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-14-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The VNC client throttling is quite subtle so will benefit from having trace
points available for live debugging.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-13-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The previous patches fix problems with throttling of forced framebuffer updates
and audio data capture that would cause the QEMU output buffer size to grow
without bound. Those fixes are graceful in that once the client catches up with
reading data from the server, everything continues operating normally.
There is some data which the server sends to the client that is impractical to
throttle. Specifically there are various pseudo framebuffer update encodings to
inform the client of things like desktop resizes, pointer changes, audio
playback start/stop, LED state and so on. These generally only involve sending
a very small amount of data to the client, but a malicious guest might be able
to do things that trigger these changes at a very high rate. Throttling them is
not practical as missed or delayed events would cause broken behaviour for the
client.
This patch thus takes a more forceful approach of setting an absolute upper
bound on the amount of data we permit to be present in the output buffer at
any time. The previous patch set a threshold for throttling the output buffer
by allowing an amount of data equivalent to one complete framebuffer update and
one seconds worth of audio data. On top of this it allowed for one further
forced framebuffer update to be queued.
To be conservative, we thus take that throttling threshold and multiply it by
5 to form an absolute upper bound. If this bound is hit during vnc_write() we
forceably disconnect the client, refusing to queue further data. This limit is
high enough that it should never be hit unless a malicious client is trying to
exploit the sever, or the network is completely saturated preventing any sending
of data on the socket.
This completes the fix for CVE-2017-15124 started in the previous patches.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-12-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The VNC server must throttle data sent to the client to prevent the 'output'
buffer size growing without bound, if the client stops reading data off the
socket (either maliciously or due to stalled/slow network connection).
The current throttling is very crude because it simply checks whether the
output buffer offset is zero. This check is disabled if the client has requested
a forced update, because we want to send these as soon as possible.
As a result, the VNC client can cause QEMU to allocate arbitrary amounts of RAM.
They can first start something in the guest that triggers lots of framebuffer
updates eg play a youtube video. Then repeatedly send full framebuffer update
requests, but never read data back from the server. This can easily make QEMU's
VNC server send buffer consume 100MB of RAM per second, until the OOM killer
starts reaping processes (hopefully the rogue QEMU process, but it might pick
others...).
To address this we make the throttling more intelligent, so we can throttle
full updates. When we get a forced update request, we keep track of exactly how
much data we put on the output buffer. We will not process a subsequent forced
update request until this data has been fully sent on the wire. We always allow
one forced update request to be in flight, regardless of what data is queued
for incremental updates or audio data. The slight complication is that we do
not initially know how much data an update will send, as this is done in the
background by the VNC job thread. So we must track the fact that the job thread
has an update pending, and not process any further updates until this job is
has been completed & put data on the output buffer.
This unbounded memory growth affects all VNC server configurations supported by
QEMU, with no workaround possible. The mitigating factor is that it can only be
triggered by a client that has authenticated with the VNC server, and who is
able to trigger a large quantity of framebuffer updates or audio samples from
the guest OS. Mostly they'll just succeed in getting the OOM killer to kill
their own QEMU process, but its possible other processes can get taken out as
collateral damage.
This is a more general variant of the similar unbounded memory usage flaw in
the websockets server, that was previously assigned CVE-2017-15268, and fixed
in 2.11 by:
commit a7b20a8efa
Author: Daniel P. Berrange <berrange@redhat.com>
Date: Mon Oct 9 14:43:42 2017 +0100
io: monitor encoutput buffer size from websocket GSource
This new general memory usage flaw has been assigned CVE-2017-15124, and is
partially fixed by this patch.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-11-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The VNC server must throttle data sent to the client to prevent the 'output'
buffer size growing without bound, if the client stops reading data off the
socket (either maliciously or due to stalled/slow network connection).
The current throttling is very crude because it simply checks whether the
output buffer offset is zero. This check must be disabled if audio capture is
enabled, because when streaming audio the output buffer offset will rarely be
zero due to queued audio data, and so this would starve framebuffer updates.
As a result, the VNC client can cause QEMU to allocate arbitrary amounts of RAM.
They can first start something in the guest that triggers lots of framebuffer
updates eg play a youtube video. Then enable audio capture, and simply never
read data back from the server. This can easily make QEMU's VNC server send
buffer consume 100MB of RAM per second, until the OOM killer starts reaping
processes (hopefully the rogue QEMU process, but it might pick others...).
To address this we make the throttling more intelligent, so we can throttle
when audio capture is active too. To determine how to throttle incremental
updates or audio data, we calculate a size threshold. Normally the threshold is
the approximate number of bytes associated with a single complete framebuffer
update. ie width * height * bytes per pixel. We'll send incremental updates
until we hit this threshold, at which point we'll stop sending updates until
data has been written to the wire, causing the output buffer offset to fall
back below the threshold.
If audio capture is enabled, we increase the size of the threshold to also
allow for upto 1 seconds worth of audio data samples. ie nchannels * bytes
per sample * frequency. This allows the output buffer to have a mixture of
incremental framebuffer updates and audio data queued, but once the threshold
is exceeded, audio data will be dropped and incremental updates will be
throttled.
This unbounded memory growth affects all VNC server configurations supported by
QEMU, with no workaround possible. The mitigating factor is that it can only be
triggered by a client that has authenticated with the VNC server, and who is
able to trigger a large quantity of framebuffer updates or audio samples from
the guest OS. Mostly they'll just succeed in getting the OOM killer to kill
their own QEMU process, but its possible other processes can get taken out as
collateral damage.
This is a more general variant of the similar unbounded memory usage flaw in
the websockets server, that was previously assigned CVE-2017-15268, and fixed
in 2.11 by:
commit a7b20a8efa
Author: Daniel P. Berrange <berrange@redhat.com>
Date: Mon Oct 9 14:43:42 2017 +0100
io: monitor encoutput buffer size from websocket GSource
This new general memory usage flaw has been assigned CVE-2017-15124, and is
partially fixed by this patch.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-10-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The logic for determining if it is possible to send an update to the client
will become more complicated shortly, so pull it out into a separate method
for easier extension later.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-9-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
According to the RFB protocol, a client sends one or more framebuffer update
requests to the server. The server can reply with a single framebuffer update
response, that covers all previously received requests. Once the client has
read this update from the server, it may send further framebuffer update
requests to monitor future changes. The client is free to delay sending the
framebuffer update request if it needs to throttle the amount of data it is
reading from the server.
The QEMU VNC server, however, has never correctly handled the framebuffer
update requests. Once QEMU has received an update request, it will continue to
send client updates forever, even if the client hasn't asked for further
updates. This prevents the client from throttling back data it gets from the
server. This change fixes the flawed logic such that after a set of updates are
sent out, QEMU waits for a further update request before sending more data.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-8-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Currently the VNC servers tracks whether a client has requested an incremental
or forced update with two boolean flags. There are only really 3 distinct
states to track, so create an enum to more accurately reflect permitted states.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-7-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The vnc_update_client() method checks the 'has_dirty' flag to see if there are
dirty regions that are pending to send to the client. Regardless of this flag,
if a forced update is requested, updates must be sent. For unknown reasons
though, the code also tries to sent updates if audio capture is enabled. This
makes no sense as audio capture state does not impact framebuffer contents, so
this check is removed.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-5-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Now that previous dead / unreachable code has been removed, we can simplify
the indentation in the vnc_client_update method.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-4-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
A previous commit:
commit 5a8be0f73d
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Wed Jul 13 12:21:20 2016 +0200
vnc: make sure we finish disconnect
Added a check for vs->disconnecting at the very start of the
vnc_update_client method. This means that the very next "if"
statement check for !vs->disconnecting always evaluates true,
and is thus redundant. This in turn means the vs->disconnecting
check at the very end of the method never evaluates true, and
is thus unreachable code.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
There is only one caller of vnc_update_client and that always passes false
for the 'sync' parameter.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-2-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Also set saved handle to zero when removing without adding a new watch.
Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Trace anything related to authentication in the VNC protocol
handshake
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170921121528.23935-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Trace anything which opens/closes/wraps a QIOChannel in the
VNC server.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170921121528.23935-2-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
I used the clang-tidy qemu-round check to generate the fix:
https://github.com/elmarco/clang-tools-extra
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
I used the clang-tidy qemu-round check to generate the fix:
https://github.com/elmarco/clang-tools-extra
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Extract the (correct) cleaning code as a new function vnc_free_addresses() then
use it to remove the memory leaks.
Reported-by: Clang Static Analyzer
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The current VNC default keyboard delay is 1ms. With that we're constantly
typing faster than the guest receives keyboard events from an XHCI attached
USB HID device.
The default keyboard delay time in the input layer however is 10ms. I don't know
how that number came to be, but empirical tests on some OpenQA driven ARM
systems show that 10ms really is a reasonable default number for the delay.
This patch moves the VNC delay also to 10ms. That way our default is much
safer (good!) and also consistent with the input layer default (also good!).
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1499863425-103133-1-git-send-email-agraf@suse.de
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Looks like #include "hw/qdev.h" is not needed here, so remove it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-id: 1497894617-12143-1-git-send-email-thuth@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ctpopl() has a better implementation than hweight_long() and ui/vnc.c
being the last user of hweight_long(), we can simply remove it.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1489415605-13105-1-git-send-email-clg@kaod.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch refactors ui/input.c to support absolute axis
minimum values other than 0. All dependent calls to qemu_input_queue_abs
have been updated to explicitly supply 0 as the axis minimum value.
Signed-off-by: Philippe Voinov <philippevoinov@gmail.com>
Message-id: 20170505133952.29885-1-philippevoinov@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
SocketAddressLegacy is a simple union, and simple unions are awkward:
they have their variant members wrapped in a "data" object on the
wire, and require additional indirections in C. SocketAddress is the
equivalent flat union. Convert all users of SocketAddressLegacy to
SocketAddress, except for existing external interfaces.
See also commit fce5d53..9445673 and 85a82e8..c5f1ae3.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-7-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Minor editing accident fixed, commit message and a comment tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The next commit will rename SocketAddressFlat to SocketAddress, and
the commit after that will replace most uses of SocketAddressLegacy by
SocketAddress, replacing most of this commit's renames right back.
Note that checkpatch emits a few "line over 80 characters" warnings.
The long lines are all temporary; the SocketAddressLegacy replacement
will shorten them again.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-5-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We have quite a few switches over SocketAddressKind. Some have case
labels for all enumeration values, others rely on a default label.
Some abort when the value isn't a valid SocketAddressKind, others
report an error then.
Unify as follows. Always provide case labels for all enumeration
values, to clarify intent. Abort when the value isn't a valid
SocketAddressKind, because the program state is messed up then.
Improve a few error messages while there.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1490895797-29094-4-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Certain features make sense only with certain address families. For
instance, passing file descriptors requires AF_UNIX. Testing
SocketAddress's saddr->type == SOCKET_ADDRESS_KIND_UNIX is obvious,
but problematic: it can't recognize AF_UNIX when type ==
SOCKET_ADDRESS_KIND_FD.
Mark such tests of saddr->type TODO. We may want to check the address
family with getsockname() there.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1490895797-29094-2-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
vnc server in reverse mode (qemu -vnc localhost:$nr,reverse) interprets
$nr as display number (i.e. with 5900 offset) in recent qemu versions.
Historical and documented behavior is interpreting $nr as port number
though. So we should bring code and documentation in line.
Given that default listening port for viewers is 5500 the 5900 offset is
pretty inconvinient, because it is simply impossible to connect to port
5500. So, lets fix the code not the docs.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1489480018-11443-1-git-send-email-kraxel@redhat.com
There is a special code path (dpy_gfx_copy) to allow graphic emulation
notify user interface code about bitblit operations carryed out by
guests. It is supported by cirrus and vnc server. The intended purpose
is to optimize display scrolls and just send over the scroll op instead
of a full display update.
This is rarely used these days though because modern guests simply don't
use the cirrus blitter any more. Any linux guest using the cirrus drm
driver doesn't. Any windows guest newer than winxp doesn't ship with a
cirrus driver any more and thus uses the cirrus as simple framebuffer.
So this code tends to bitrot and bugs can go unnoticed for a long time.
See for example commit "3e10c3e vnc: fix qemu crash because of SIGSEGV"
which fixes a bug lingering in the code for almost a year, added by
commit "c7628bf vnc: only alloc server surface with clients connected".
Also the vnc server will throttle the frame rate in case it figures the
network can't keep up (send buffers are full). This doesn't work with
dpy_gfx_copy, for any copy operation sent to the vnc client we have to
send all outstanding updates beforehand, otherwise the vnc client might
run the client side blit on outdated data and thereby corrupt the
display. So this dpy_gfx_copy "optimization" might even make things
worse on slow network links.
Lets kill it once for all.
Oh, and one more reason: Turns out (after writing the patch) we have a
security bug in that code path ...
Fixes: CVE-2016-9603
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1489494419-14340-1-git-send-email-kraxel@redhat.com
This change allows the listen address and websocket address
options for -vnc to be repeated. This causes the VNC server
to listen on multiple addresses. e.g.
$ $QEMU -vnc vnc=localhost:1,vnc=unix:/tmp/vnc,\
websocket=127.0.0.1:8080,websocket=[::]:8081
results in listening on
127.0.0.1:5901, 127.0.0.1:8080, ::1:5901, :::8081 & /tmp/vnc
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-9-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Remove the limitation that the VNC server can only listen on
a single resolved IP address. This uses the new DNS resolver
API to resolve a SocketAddress struct into an array of
SocketAddress structs containing raw IP addresses. The VNC
server will then attempt to listen on all resolved IP addresses.
The server must successfully listen on at least one of the
resolved IP addresses, otherwise an error will be reported.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-7-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The code which takes a SocketAddress and connects/listens on the
network is going to get more complicated to deal with multiple
listeners. Pull it out into a separate method to avoid making the
vnc_display_open method even more complex.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-6-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
