This commit results in unexpected termination of the TLS connection.
When 'fd_can_read' returns 0, the code goes on to pass a zero length
buffer to qio_channel_read. The TLS impl calls into gnutls_recv()
with this zero length buffer, at which point GNUTLS returns an error
GNUTLS_E_INVALID_REQUEST. This is treated as fatal by QEMU's TLS code
resulting in the connection being torn down by the chardev.
Simply skipping the qio_channel_read when the buffer length is zero
is also not satisfactory, as it results in a high CPU burn busy loop
massively slowing QEMU's functionality.
The proper solution is to avoid tcp_chr_read being called at all
unless the frontend is able to accept more data. This will be done
in a followup commit.
This reverts commit 462945cd22
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The socket chardev often has 2 GSource object registered against the
same FD. One is registered all the time and is just intended to handle
POLLHUP events, while the other gets registered & unregistered on the
fly as the frontend is ready to receive more data or not.
It is very common for poll() to signal a POLLHUP event at the same time
as there is pending incoming data from the disconnected client. It is
therefore essential to process incoming data prior to processing HUP.
The problem with having 2 GSource on the same FD is that there is no
guaranteed ordering of execution between them, so the chardev code may
process HUP first and thus discard data.
This failure scenario is non-deterministic but can be seen fairly
reliably by reverting a7077b8e35, and
then running 'tests/unit/test-char', which will sometimes fail with
missing data.
Ideally QEMU would only have 1 GSource, but that's a complex code
refactoring job. The next best solution is to try to ensure ordering
between the 2 GSource objects. This can be achieved by lowering the
priority of the HUP GSource, so that it is never dispatched if the
main GSource is also ready to dispatch. Counter-intuitively, lowering
the priority of a GSource is done by raising its priority number.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Commit ffda5db65a ("io/channel-tls: fix handling of bigger read buffers")
changed the behavior of the TLS io channels to schedule a second reading
attempt if there is still incoming data pending. This caused a regression
with backends like the sclpconsole that check in their read function that
the sender does not try to write more bytes to it than the device can
currently handle.
The problem can be reproduced like this:
1) In one terminal, do this:
mkdir qemu-pki
cd qemu-pki
openssl genrsa 2048 > ca-key.pem
openssl req -new -x509 -nodes -days 365000 -key ca-key.pem -out ca-cert.pem
# enter some dummy value for the cert
openssl genrsa 2048 > server-key.pem
openssl req -new -x509 -nodes -days 365000 -key server-key.pem \
-out server-cert.pem
# enter some other dummy values for the cert
gnutls-serv --echo --x509cafile ca-cert.pem --x509keyfile server-key.pem \
--x509certfile server-cert.pem -p 8338
2) In another terminal, do this:
wget https://download.fedoraproject.org/pub/fedora-secondary/releases/39/Cloud/s390x/images/Fedora-Cloud-Base-39-1.5.s390x.qcow2
qemu-system-s390x -nographic -nodefaults \
-hda Fedora-Cloud-Base-39-1.5.s390x.qcow2 \
-object tls-creds-x509,id=tls0,endpoint=client,verify-peer=false,dir=$PWD/qemu-pki \
-chardev socket,id=tls_chardev,host=localhost,port=8338,tls-creds=tls0 \
-device sclpconsole,chardev=tls_chardev,id=tls_serial
QEMU then aborts after a second or two with:
qemu-system-s390x: ../hw/char/sclpconsole.c:73: chr_read: Assertion
`size <= SIZE_BUFFER_VT220 - scon->iov_data_len' failed.
Aborted (core dumped)
It looks like the second read does not trigger the chr_can_read() function
to be called before the second read, which should normally always be done
before sending bytes to a character device to see how much it can handle,
so the s->max_size in tcp_chr_read() still contains the old value from the
previous read. Let's make sure that we use the up-to-date value by calling
tcp_chr_read_poll() again here.
Fixes: ffda5db65a ("io/channel-tls: fix handling of bigger read buffers")
Buglink: https://issues.redhat.com/browse/RHEL-24614
Reviewed-by: "Daniel P. Berrangé" <berrange@redhat.com>
Message-ID: <20240229104339.42574-1-thuth@redhat.com>
Reviewed-by: Antoine Damhet <antoine.damhet@blade-group.com>
Tested-by: Antoine Damhet <antoine.damhet@blade-group.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
SocketAddress branch @fd is documented in enum SocketAddressType,
unlike the other branches. That's because the branch's type is String
from common.json.
Use a local copy of String, so we can put the documentation in the
usual place.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240205074709.3613229-14-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The chardev socket backend will unref the QIOChannel object while
it is still potentially open. When using TLS there could be a
pending TLS handshake taking place. If the channel is left open
then when the TLS handshake callback runs, it can end up accessing
free'd memory in the tcp_chr_tls_handshake method.
Closing the QIOChannel will unregister any pending handshake
source.
Reported-by: jiangyegen <jiangyegen@huawei.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This can help to debug connection issues.
Related to:
https://bugzilla.redhat.com/show_bug.cgi?id=2196182
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230510072531.3937189-1-marcandre.lureau@redhat.com>
After live migration with virtio block device, qemu crash at:
#0 0x000055914f46f795 in object_dynamic_cast_assert (obj=0x559151b7b090, typename=0x55914f80fbc4 "qio-channel", file=0x55914f80fb90 "/images/testvfe/sw/qemu.gerrit/include/io/channel.h", line=30, func=0x55914f80fcb8 <__func__.17257> "QIO_CHANNEL") at ../qom/object.c:872
#1 0x000055914f480d68 in QIO_CHANNEL (obj=0x559151b7b090) at /images/testvfe/sw/qemu.gerrit/include/io/channel.h:29
#2 0x000055914f4812f8 in qio_net_listener_set_client_func_full (listener=0x559151b7a720, func=0x55914f580b97 <tcp_chr_accept>, data=0x5591519f4ea0, notify=0x0, context=0x0) at ../io/net-listener.c:166
#3 0x000055914f580059 in tcp_chr_update_read_handler (chr=0x5591519f4ea0) at ../chardev/char-socket.c:637
#4 0x000055914f583dca in qemu_chr_be_update_read_handlers (s=0x5591519f4ea0, context=0x0) at ../chardev/char.c:226
#5 0x000055914f57b7c9 in qemu_chr_fe_set_handlers_full (b=0x559152bf23a0, fd_can_read=0x0, fd_read=0x0, fd_event=0x0, be_change=0x0, opaque=0x0, context=0x0, set_open=false, sync_state=true) at ../chardev/char-fe.c:279
#6 0x000055914f57b86d in qemu_chr_fe_set_handlers (b=0x559152bf23a0, fd_can_read=0x0, fd_read=0x0, fd_event=0x0, be_change=0x0, opaque=0x0, context=0x0, set_open=false) at ../chardev/char-fe.c:304
#7 0x000055914f378caf in vhost_user_async_close (d=0x559152bf21a0, chardev=0x559152bf23a0, vhost=0x559152bf2420, cb=0x55914f2fb8c1 <vhost_user_blk_disconnect>) at ../hw/virtio/vhost-user.c:2725
#8 0x000055914f2fba40 in vhost_user_blk_event (opaque=0x559152bf21a0, event=CHR_EVENT_CLOSED) at ../hw/block/vhost-user-blk.c:395
#9 0x000055914f58388c in chr_be_event (s=0x5591519f4ea0, event=CHR_EVENT_CLOSED) at ../chardev/char.c:61
#10 0x000055914f583905 in qemu_chr_be_event (s=0x5591519f4ea0, event=CHR_EVENT_CLOSED) at ../chardev/char.c:81
#11 0x000055914f581275 in char_socket_finalize (obj=0x5591519f4ea0) at ../chardev/char-socket.c:1083
#12 0x000055914f46f073 in object_deinit (obj=0x5591519f4ea0, type=0x5591519055c0) at ../qom/object.c:680
#13 0x000055914f46f0e5 in object_finalize (data=0x5591519f4ea0) at ../qom/object.c:694
#14 0x000055914f46ff06 in object_unref (objptr=0x5591519f4ea0) at ../qom/object.c:1202
#15 0x000055914f4715a4 in object_finalize_child_property (obj=0x559151b76c50, name=0x559151b7b250 "char3", opaque=0x5591519f4ea0) at ../qom/object.c:1747
#16 0x000055914f46ee86 in object_property_del_all (obj=0x559151b76c50) at ../qom/object.c:632
#17 0x000055914f46f0d2 in object_finalize (data=0x559151b76c50) at ../qom/object.c:693
#18 0x000055914f46ff06 in object_unref (objptr=0x559151b76c50) at ../qom/object.c:1202
#19 0x000055914f4715a4 in object_finalize_child_property (obj=0x559151b6b560, name=0x559151b76630 "chardevs", opaque=0x559151b76c50) at ../qom/object.c:1747
#20 0x000055914f46ef67 in object_property_del_child (obj=0x559151b6b560, child=0x559151b76c50) at ../qom/object.c:654
#21 0x000055914f46f042 in object_unparent (obj=0x559151b76c50) at ../qom/object.c:673
#22 0x000055914f58632a in qemu_chr_cleanup () at ../chardev/char.c:1189
#23 0x000055914f16c66c in qemu_cleanup () at ../softmmu/runstate.c:830
#24 0x000055914eee7b9e in qemu_default_main () at ../softmmu/main.c:38
#25 0x000055914eee7bcc in main (argc=86, argv=0x7ffc97cb8d88) at ../softmmu/main.c:48
In char_socket_finalize after s->listener freed, event callback function
vhost_user_blk_event will be called to handle CHR_EVENT_CLOSED.
vhost_user_blk_event is calling qio_net_listener_set_client_func_full which
is still using s->listener.
Setting s->listener = NULL after object_unref(OBJECT(s->listener)) can
solve this issue.
Signed-off-by: Yajun Wu <yajunw@nvidia.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Message-Id: <20230214021430.3638579-1-yajunw@nvidia.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
MSG_PEEK peeks at the channel, The data is treated as unread and
the next read shall still return this data. This support is
currently added only for socket class. Extra parameter 'flags'
is added to io_readv calls to pass extra read flags like MSG_PEEK.
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: manish.mishra <manish.mishra@nutanix.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The has_FOO for pointer-valued FOO are redundant, except for arrays.
They are also a nuisance to work with. Recent commit "qapi: Start to
elide redundant has_FOO in generated C" provided the means to elide
them step by step. This is the step for qapi/char.json.
Said commit explains the transformation in more detail. The invariant
violations mentioned there do not occur here.
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221104160712.3005652-12-armbru@redhat.com>
Now that AF_UNIX has come to Windows, update the existing logic in
qemu_chr_compute_filename() and qmp_chardev_open_socket() for Windows.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220802075200.907360-4-bmeng.cn@gmail.com>
The qemu_*block() functions are meant to be be used with sockets (the
win32 implementation expects SOCKET)
Over time, those functions where used with Win32 SOCKET or
file-descriptors interchangeably. But for portability, they must only be
used with socket-like file-descriptors. FDs can use
g_unix_set_fd_nonblocking() instead.
Rename the functions with "socket" in the name to prevent bad usages.
This is effectively reverting commit f9e8cacc55 ("oslib-posix:
rename socket_set_nonblock() to qemu_set_nonblock()").
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
After the return from tcp_chr_recv, tcp_chr_sync_read calls into a
function which eventually makes a system call and may clobber errno.
Make a copy of errno right after tcp_chr_recv and restore the errno on
return from tcp_chr_sync_read.
Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
Message-Id: <20211111153354.18807-4-rvkagan@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
tcp_chr_recv communicates the specific error condition to the caller via
errno. However, after setting it, it may call into some system calls or
library functions which can clobber the errno.
Avoid this by moving the errno assignment to the end of the function.
Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
Message-Id: <20211111153354.18807-3-rvkagan@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
The following patches are going to use CharSocket as a base class for
sockets that are created with a given fd (without a given address).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Simple unions predate flat unions. Having both complicates the QAPI
schema language and the QAPI generator. We haven't been using simple
unions in new code for a long time, because they are less flexible and
somewhat awkward on the wire.
To prepare for their removal, convert simple union SocketAddressLegacy
to an equivalent flat one, with existing enum SocketAddressType
replacing implicit enum type SocketAddressLegacyKind. Adds some
boilerplate to the schema, which is a bit ugly, but a lot easier to
maintain than the simple union feature.
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210917143134.412106-9-armbru@redhat.com>
Better reflect the command line version of the socket address arguments,
following the now recommended long-form opt=on syntax.
Complement/fixes commit 9d902d51 "chardev: do not use short form boolean
options in non-QemuOpts character device descriptions".
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Avoid accessing QCryptoTLSCreds internals by using
the qcrypto_tls_creds_check_endpoint() helper.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When changing from chardev-socket (which supports yank) to
chardev-socket again, it fails, because the new chardev attempts
to register a new yank instance. This in turn fails, as there
still is the yank instance from the current chardev. Also,
the old chardev shouldn't unregister the yank instance when it
is freed.
To fix this, now the new chardev only registers a yank instance if
the current chardev doesn't support yank and thus hasn't registered
one already. Also, when the old chardev is freed, it now only
unregisters the yank instance if the new chardev doesn't need it.
If the initialization of the new chardev fails, it still has
chr->handover_yank_instance set and won't unregister the yank
instance when it is freed.
s->registered_yank is always true here, as chardev-change only works
on user-visible chardevs and those are guraranteed to register a
yank instance as they are initialized via
chardev_new()
qemu_char_open()
cc->open() (qmp_chardev_open_socket()).
Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Li Zhang <li.zhang@cloud.ionos.com>
Message-Id: <9637888d7591d2971975188478bb707299a1dc04.1617127849.git.lukasstraub2@web.de>
Remove dependency on qiochannel by removing yank_generic_iochannel and
letting migration and chardev use their own yank function for
iochannel.
Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20ff143fc2db23e27cd41d38043e481376c9cec1.1616521341.git.lukasstraub2@web.de>
This only makes sense conceptually when used with listener chardevs.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The "delay" option was introduced as a way to enable Nagle's algorithm
with ",nodelay". Since the short form for boolean options has now been
deprecated, introduce a more properly named "nodelay" option. The "delay"
option remains as an undocumented option.
"delay" and "nodelay" are mutually exclusive. Because the check is
done at consumption time, the code also rejects them if one of the
two is specified via -set.
Based-on: <20210226080526.651705-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Options such as "-gdb" or "-serial" accept a part-QemuOpts part-parsed-by-hand
character device description. Do not use short form boolean options in the
QemuOpts part.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch checks that ioc is not null before
using it in tcp socket tcp_chr_add_watch function.
The failure occurs in replay mode of the execution,
when monitor and serial port are tcp servers,
and there are no clients connected to them:
-monitor tcp:127.0.0.1:8081,server,nowait
-serial tcp:127.0.0.1:8082,server,nowait
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <161284977034.741841.12565530923825663110.stgit@pasha-ThinkPad-X280>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Not all chardevs are created via qmp_chardev_open_socket(), and those
should not call the yank function registration, as this will eventually
assert() not being registered.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210204105232.834642-20-marcandre.lureau@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Register a yank function to shutdown the socket on yank.
Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1f4eeed1d066c6cbb8d05ffa9585f6e87b34aac6.1609167865.git.lukasstraub2@web.de>
Acked-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The abstract socket namespace is a non-portable Linux extension. An
attempt to use it elsewhere should fail with ENOENT (the abstract
address looks like a "" pathname, which does not resolve). We report
this failure like
Failed to connect socket abc: No such file or directory
Tolerable, although ENOTSUP would be better.
However, introspection lies: it has @abstract regardless of host
support. Easy enough to fix: since Linux provides them since 2.2,
'if': 'defined(CONFIG_LINUX)' should do.
The above failure becomes
Parameter 'backend.data.addr.data.abstract' is unexpected
I consider this an improvement.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Commit 776b97d360 "qemu-sockets: add abstract UNIX domain socket
support" neglected to update qemu_chr_socket_address(). It shows
shows neither @abstract nor @tight. Fix that.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
An optional bool member of a QAPI struct can be false, true, or absent.
The previous commit demonstrated that socket_listen() and
socket_connect() are broken for absent @tight, and indeed QMP chardev-
add also defaults absent member @tight to false instead of true.
In C, QAPI members are represented by two fields, has_MEMBER and MEMBER.
We have:
has_MEMBER MEMBER
false true false
true true true
absent false false/ignore
When has_MEMBER is false, MEMBER should be set to false on write, and
ignored on read.
For QMP, the QAPI visitors handle absent @tight by setting both
@has_tight and @tight to false. unix_listen_saddr() and
unix_connect_saddr() however use @tight only, disregarding @has_tight.
This is wrong and means that absent @tight defaults to false whereas it
should default to true.
The same is true for @has_abstract, though @abstract defaults to
false and therefore has the same behavior for all of QMP, HMP and CLI.
Fix unix_listen_saddr() and unix_connect_saddr() to check
@has_abstract/@has_tight, and to default absent @tight to true.
However, this is only half of the story. HMP chardev-add and CLI
-chardev so far correctly defaulted @tight to true, but defaults to
false again with the above fix for HMP and CLI. In fact, the "tight"
and "abstract" options now break completely.
Digging deeper, we find that qemu_chr_parse_socket() also ignores
@has_tight, leaving it false when it sets @tight. That is also wrong,
but the two wrongs cancelled out. Fix qemu_chr_parse_socket() to set
@has_tight and @has_abstract; writing testcases for HMP and CLI is left
for another day.
Fixes: 776b97d360
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.
Patch generated using:
$ ./scripts/codeconverter/converter.py -i \
--pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')
which will split "typdef struct { ... } TypedefName"
declarations.
Followed by:
$ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
$(git grep -l '' -- '*.[ch]')
which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
With a reconnect socket, qemu_char_open() will start a background
thread. It should keep a reference on the chardev.
Fixes invalid read:
READ of size 8 at 0x6040000ac858 thread T7
#0 0x5555598d37b8 in unix_connect_saddr /home/elmarco/src/qq/util/qemu-sockets.c:954
#1 0x5555598d4751 in socket_connect /home/elmarco/src/qq/util/qemu-sockets.c:1109
#2 0x555559707c34 in qio_channel_socket_connect_sync /home/elmarco/src/qq/io/channel-socket.c:145
#3 0x5555596adebb in tcp_chr_connect_client_task /home/elmarco/src/qq/chardev/char-socket.c:1104
#4 0x555559723d55 in qio_task_thread_worker /home/elmarco/src/qq/io/task.c:123
#5 0x5555598a6731 in qemu_thread_start /home/elmarco/src/qq/util/qemu-thread-posix.c:519
#6 0x7ffff40d4431 in start_thread (/lib64/libpthread.so.0+0x9431)
#7 0x7ffff40029d2 in __clone (/lib64/libc.so.6+0x1019d2)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200420112012.567284-1-marcandre.lureau@redhat.com>
When the disconnect event is triggered in the connecting stage,
the tcp_chr_disconnect_locked may be called twice.
The first call:
#0 qemu_chr_socket_restart_timer (chr=0x55555582ee90) at chardev/char-socket.c:120
#1 0x000055555558e38c in tcp_chr_disconnect_locked (chr=<optimized out>) at chardev/char-socket.c:490
#2 0x000055555558e3cd in tcp_chr_disconnect (chr=0x55555582ee90) at chardev/char-socket.c:497
#3 0x000055555558ea32 in tcp_chr_new_client (chr=chr@entry=0x55555582ee90, sioc=sioc@entry=0x55555582f0b0) at chardev/char-socket.c:892
#4 0x000055555558eeb8 in qemu_chr_socket_connected (task=0x55555582f300, opaque=<optimized out>) at chardev/char-socket.c:1090
#5 0x0000555555574352 in qio_task_complete (task=task@entry=0x55555582f300) at io/task.c:196
#6 0x00005555555745f4 in qio_task_thread_result (opaque=0x55555582f300) at io/task.c:111
#7 qio_task_wait_thread (task=0x55555582f300) at io/task.c:190
#8 0x000055555558f17e in tcp_chr_wait_connected (chr=0x55555582ee90, errp=0x555555802a08 <error_abort>) at chardev/char-socket.c:1013
#9 0x0000555555567cbd in char_socket_client_reconnect_test (opaque=0x5555557fe020 <client8unix>) at tests/test-char.c:1152
The second call:
#0 0x00007ffff5ac3277 in raise () from /lib64/libc.so.6
#1 0x00007ffff5ac4968 in abort () from /lib64/libc.so.6
#2 0x00007ffff5abc096 in __assert_fail_base () from /lib64/libc.so.6
#3 0x00007ffff5abc142 in __assert_fail () from /lib64/libc.so.6
#4 0x000055555558d10a in qemu_chr_socket_restart_timer (chr=0x55555582ee90) at chardev/char-socket.c:125
#5 0x000055555558df0c in tcp_chr_disconnect_locked (chr=<optimized out>) at chardev/char-socket.c:490
#6 0x000055555558df4d in tcp_chr_disconnect (chr=0x55555582ee90) at chardev/char-socket.c:497
#7 0x000055555558e5b2 in tcp_chr_new_client (chr=chr@entry=0x55555582ee90, sioc=sioc@entry=0x55555582f0b0) at chardev/char-socket.c:892
#8 0x000055555558e93a in tcp_chr_connect_client_sync (chr=chr@entry=0x55555582ee90, errp=errp@entry=0x7fffffffd178) at chardev/char-socket.c:944
#9 0x000055555558ec78 in tcp_chr_wait_connected (chr=0x55555582ee90, errp=0x555555802a08 <error_abort>) at chardev/char-socket.c:1035
#10 0x000055555556804b in char_socket_client_test (opaque=0x5555557fe020 <client8unix>) at tests/test-char.c:1023
Run test/test-char to reproduce this issue.
test-char: chardev/char-socket.c:125: qemu_chr_socket_restart_timer: Assertion `!s->reconnect_timer' failed.
Signed-off-by: Li Feng <fengli@smartx.com>
Acked-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200522025554.41063-1-fengli@smartx.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>
Errors are already freed by error_report_err, so we only need to call
error_free when that function is not called.
Cc: qemu-stable@nongnu.org
Signed-off-by: lichun <lichun@ruijie.com.cn>
Message-Id: <20200621213017.17978-1-lichun@ruijie.com.cn>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message improved, cc: qemu-stable]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
In tcp_chr_sync_read function, there is a possibility of socket
disconnection during blocking read, then tcp_chr_hup function would clean up
the qio channel pointers(i.e ioc, sioc).
Signed-off-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>
Message-Id: <1587289900-29485-1-git-send-email-sai.pavan.boddu@xilinx.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
During testing of the vhost-user-blk reconnect functionality the qemu
SIGSEGV was triggered:
start qemu as:
x86_64-softmmu/qemu-system-x86_64 -m 1024M -M q35 \
-object memory-backend-file,id=ram-node0,size=1024M,mem-path=/dev/shm/qemu,share=on \
-numa node,cpus=0,memdev=ram-node0 \
-chardev socket,id=chardev0,path=./vhost.sock,noserver,reconnect=1 \
-device vhost-user-blk-pci,chardev=chardev0,num-queues=4 --enable-kvm
start vhost-user-blk daemon:
./vhost-user-blk -s ./vhost.sock -b test-img.raw
If vhost-user-blk will be killed during the vhost initialization
process, for instance after getting VHOST_SET_VRING_CALL command, then
QEMU will fail with the following backtrace:
Thread 1 "qemu-system-x86" received signal SIGSEGV, Segmentation fault.
0x00005555559272bb in vhost_user_read (dev=0x7fffef2d53e0, msg=0x7fffffffd5b0)
at ./hw/virtio/vhost-user.c:260
260 CharBackend *chr = u->user->chr;
#0 0x00005555559272bb in vhost_user_read (dev=0x7fffef2d53e0, msg=0x7fffffffd5b0)
at ./hw/virtio/vhost-user.c:260
#1 0x000055555592acb8 in vhost_user_get_config (dev=0x7fffef2d53e0, config=0x7fffef2d5394 "", config_len=60)
at ./hw/virtio/vhost-user.c:1645
#2 0x0000555555925525 in vhost_dev_get_config (hdev=0x7fffef2d53e0, config=0x7fffef2d5394 "", config_len=60)
at ./hw/virtio/vhost.c:1490
#3 0x00005555558cc46b in vhost_user_blk_device_realize (dev=0x7fffef2d51a0, errp=0x7fffffffd8f0)
at ./hw/block/vhost-user-blk.c:429
#4 0x0000555555920090 in virtio_device_realize (dev=0x7fffef2d51a0, errp=0x7fffffffd948)
at ./hw/virtio/virtio.c:3615
#5 0x0000555555a9779c in device_set_realized (obj=0x7fffef2d51a0, value=true, errp=0x7fffffffdb88)
at ./hw/core/qdev.c:891
...
The problem is that vhost_user_write doesn't get an error after
disconnect and try to call vhost_user_read(). The tcp_chr_write()
routine should return -1 in case of disconnect. Indicate the EIO error
if this routine is called in the disconnected state.
Signed-off-by: Dima Stepanov <dimastep@yandex-team.ru>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <aeb7806bfc945faadf09f64dcfa30f59de3ac053.1590396396.git.dimastep@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Replace
error_report("...: %s", ..., error_get_pretty(err));
by
error_reportf_err(err, "...: ", ...);
One of the replaced messages lacked a colon. Add it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200505101908.6207-6-armbru@redhat.com>
unix_listen/connect_saddr now support abstract address types
two aditional BOOL switches are introduced:
tight: whether to set @addrlen to the minimal string length,
or the maximum sun_path length. default is TRUE
abstract: whether we use abstract address. default is FALSE
cli example:
-monitor unix:/tmp/unix.socket,abstract,tight=off
OR
-chardev socket,path=/tmp/unix.socket,id=unix1,abstract,tight=on
Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The only way object_property_add() can fail is when a property with
the same name already exists. Since our property names are all
hardcoded, failure is a programming error, and the appropriate way to
handle it is passing &error_abort.
Same for its variants, except for object_property_add_child(), which
additionally fails when the child already has a parent. Parentage is
also under program control, so this is a programming error, too.
We have a bit over 500 callers. Almost half of them pass
&error_abort, slightly fewer ignore errors, one test case handles
errors, and the remaining few callers pass them to their own callers.
The previous few commits demonstrated once again that ignoring
programming errors is a bad idea.
Of the few ones that pass on errors, several violate the Error API.
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL. Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call. ich9_pm_add_properties(), sparc32_ledma_realize(),
sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
are wrong that way.
When the one appropriate choice of argument is &error_abort, letting
users pick the argument is a bad idea.
Drop parameter @errp and assert the preconditions instead.
There's one exception to "duplicate property name is a programming
error": the way object_property_add() implements the magic (and
undocumented) "automatic arrayification". Don't drop @errp there.
Instead, rename object_property_add() to object_property_try_add(),
and add the obvious wrapper object_property_add().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-15-armbru@redhat.com>
[Two semantic rebase conflicts resolved]
There's a race condition in which the tcp_chr_read() ioc handler can
close a connection that is being written to from another thread.
Running iotest 136 in a loop triggers this problem and crashes QEMU.
(gdb) bt
#0 0x00005558b842902d in object_get_class (obj=0x0) at qom/object.c:860
#1 0x00005558b84f92db in qio_channel_writev_full (ioc=0x0, iov=0x7ffc355decf0, niov=1, fds=0x0, nfds=0, errp=0x0) at io/channel.c:76
#2 0x00005558b84e0e9e in io_channel_send_full (ioc=0x0, buf=0x5558baf5beb0, len=138, fds=0x0, nfds=0) at chardev/char-io.c:123
#3 0x00005558b84e4a69 in tcp_chr_write (chr=0x5558ba460380, buf=0x5558baf5beb0 "...", len=138) at chardev/char-socket.c:135
#4 0x00005558b84dca55 in qemu_chr_write_buffer (s=0x5558ba460380, buf=0x5558baf5beb0 "...", len=138, offset=0x7ffc355dedd0, write_all=false) at chardev/char.c:112
#5 0x00005558b84dcbc2 in qemu_chr_write (s=0x5558ba460380, buf=0x5558baf5beb0 "...", len=138, write_all=false) at chardev/char.c:147
#6 0x00005558b84dfb26 in qemu_chr_fe_write (be=0x5558ba476610, buf=0x5558baf5beb0 "...", len=138) at chardev/char-fe.c:42
#7 0x00005558b8088c86 in monitor_flush_locked (mon=0x5558ba476610) at monitor.c:406
#8 0x00005558b8088e8c in monitor_puts (mon=0x5558ba476610, str=0x5558ba921e49 "") at monitor.c:449
#9 0x00005558b8089178 in qmp_send_response (mon=0x5558ba476610, rsp=0x5558bb161600) at monitor.c:498
#10 0x00005558b808920c in monitor_qapi_event_emit (event=QAPI_EVENT_SHUTDOWN, qdict=0x5558bb161600) at monitor.c:526
#11 0x00005558b8089307 in monitor_qapi_event_queue_no_reenter (event=QAPI_EVENT_SHUTDOWN, qdict=0x5558bb161600) at monitor.c:551
#12 0x00005558b80896c0 in qapi_event_emit (event=QAPI_EVENT_SHUTDOWN, qdict=0x5558bb161600) at monitor.c:626
#13 0x00005558b855f23b in qapi_event_send_shutdown (guest=false, reason=SHUTDOWN_CAUSE_HOST_QMP_QUIT) at qapi/qapi-events-run-state.c:43
#14 0x00005558b81911ef in qemu_system_shutdown (cause=SHUTDOWN_CAUSE_HOST_QMP_QUIT) at vl.c:1837
#15 0x00005558b8191308 in main_loop_should_exit () at vl.c:1885
#16 0x00005558b819140d in main_loop () at vl.c:1924
#17 0x00005558b8198c84 in main (argc=18, argv=0x7ffc355df3f8, envp=0x7ffc355df490) at vl.c:4665
This patch adds a lock to protect tcp_chr_disconnect() and
socket_reconnect_timeout()
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Message-Id: <1565625509-404969-3-git-send-email-andrey.shinkevich@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 767abe7 ("chardev: forbid 'wait' option with client sockets")
is a bit too strict. Current libvirt always set wait=false, and will
thus fail to add client chardev.
Make the code more permissive, allowing wait=false with client socket
chardevs. Deprecate usage of 'wait' with client sockets.
Fixes: 767abe7f49
Cc: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190415163337.2795-1-marcandre.lureau@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Currently any client which can complete the TLS handshake is able to use
a chardev server. The server admin can turn on the 'verify-peer' option
for the x509 creds to require the client to provide a x509
certificate. This means the client will have to acquire a certificate
from the CA before they are permitted to use the chardev server. This is
still a fairly low bar.
This adds a 'tls-authz=OBJECT-ID' option to the socket chardev backend
which takes the ID of a previously added 'QAuthZ' object instance. This
will be used to validate the client's x509 distinguished name. Clients
failing the check will not be permitted to use the chardev server.
For example to setup authorization that only allows connection from a
client whose x509 certificate distinguished name contains 'CN=fred', you
would use:
$QEMU -object tls-creds-x509,id=tls0,dir=/home/berrange/qemutls,\
endpoint=server,verify-peer=yes \
-object authz-simple,id=authz0,identity=CN=laptop.example.com,,\
O=Example Org,,L=London,,ST=London,,C=GB \
-chardev socket,host=127.0.0.1,port=9000,server,\
tls-creds=tls0,tls-authz=authz0 \
...other qemu args...
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
If the socket is connecting or connected, tcp_chr_update_read_handler will
be called but it should not set the NetListener's callbacks again.
Otherwise, tcp_chr_accept is invoked while the socket is in connected
state and you get an assertion failure.
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When the 'reconnect' option is given for a client connection, the
qmp_chardev_open_socket_client method will run an asynchronous
connection attempt. The QIOChannel socket executes this is a single use
background thread, so the connection will succeed immediately (assuming
the server is listening). The chardev, however, won't get the result
from this background thread until the main loop starts running and
processes idle callbacks.
Thus when tcp_chr_wait_connected is run s->ioc will be NULL, but the
state will be TCP_CHARDEV_STATE_CONNECTING, and there may already
be an established connection that will be associated with the chardev
by the pending idle callback. tcp_chr_wait_connected doesn't check the
state, only s->ioc, so attempts to establish another connection
synchronously.
If the server allows multiple connections this is unhelpful but not a
fatal problem as the duplicate connection will get ignored by the
tcp_chr_new_client method when it sees the state is already connected.
If the server only supports a single connection, however, the
tcp_chr_wait_connected method will hang forever because the server will
not accept its synchronous connection attempt until the first connection
is closed.
To deal with this tcp_chr_wait_connected needs to synchronize with the
completion of the background connection task. To do this it needs to
create the QIOTask directly and use the qio_task_wait_thread method.
This will cancel the pending idle callback and directly dispatch the
task completion callback, allowing the connection to be associated
with the chardev. If the background connection failed, it can still
attempt a new synchronous connection.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20190211182442.8542-15-berrange@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
