150 Commits

Author SHA1 Message Date
Peng Liang
8a1915c4d6 rpc: Fix memory leak of fds
In virSystemdActivationClaimFDs, the memory of ent->fds has been stolen
and stored in fds, but fds is never freed, which causes a memory leak.
Fix it by declaring fds as g_autofree.

Reported-by: Jie Tang <tangjie18@huawei.com>
Signed-off-by: Peng Liang <liangpeng10@huawei.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2022-03-04 10:53:03 +01:00
Jiri Denemark
b21b4b56f9 virnetserver: Make pool job name less generic
The generic "rpc-worker" name becomes a name of the associated task,
which may than appear in logs and bring some confusion. Let's add a
server name to it so that one can easily see which daemon the task
belongs to, which is especially useful for split daemons. And since the
name would be too long, we can drop the "-worker" part and just keep it
as "rpc-*" and "prio-rpc-*".

Such confusing entries can, for example, be found in audit log when
SELinux is complaining that "rpc-worker" was denied access to something.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-12-01 14:36:30 +01:00
Jiri Denemark
a8efdb4eed virnetserver: Use autoptr for virNetServer and virNetServerClient
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-12-01 14:36:30 +01:00
Jiri Denemark
a44738231e virnetserver: Format functions consistently
The file used a pretty inconsistent style for formatting function
headers. Return types were both separate and on the same line as
function names and functions were separated by one, two, and sometimes
even three empty lines. Let's make it consistent by honoring our
preferred coding style.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-12-01 14:36:30 +01:00
Michal Privoznik
0c8f1aeddf virthreadpool: Allow setting identity for workers
In some cases the worker func running inside the pool may rely on
virIdentity. While worker func could check for identity and set
one it is not optimal - it may not have access to the identity of
the thread creating the pool and thus would have to call
virIdentityGetSystem(). Allow passing identity when creating the
pool.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2021-10-27 17:11:29 +02:00
Michal Privoznik
f3ab818984 rpc: Temporarily stop accept()-ing new clients on EMFILE
This commit is related to 5de203f879 which I pushed a few days
ago. While that commit prioritized closing clients socket over
the rest of I/O process, this one goes one step further and
temporarily suspends processing new connection requests.

A brief recapitulation of the problem:

1) assume that libvirt is at the top of RLIMIT_NOFILE (that is no
   new FDs can be opened).

2) we have a client trying to connect to a UNIX/TCP socket

Because of 2) our event loop sees POLLIN on the socket and thus
calls virNetServerServiceAccept(). But since no new FDs can be
opened (because of 1)) the request is not handled and we will get
the same event on next iteration. The poll() will exit
immediately because there is an event on the socket.  Thus we end
up in an endless loop.

To break the loop and stop burning CPU cycles we can stop
listening for events on the socket and set up a timer tho enable
listening again after some time (I chose 5 seconds because of no
obvious reason).

There's another area where we play with temporarily suspending
accept() of new clients - when a client disconnects and we check
max_clients against number of current clients. Problem here is
that max_clients can be orders of magnitude larger than
RLIMIT_NOFILE but more importantly, what this code considers
client disconnect is not equal to closing client's FD.
A client disconnecting means that the corresponding client
structure is removed from the internal list of clients. Closing
of the client's FD is done from event loop - asynchronously.

To avoid this part stepping on the toes of my fix, let's make the
code NOP if socket timer (as described above) is active.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2021-10-20 16:25:22 +02:00
Peter Krempa
30b6be3f8c virNetServerGetClients: Remove pointless cleanup
'list' will always be NULL when reaching 'virObjectListFreeCount' thus
we can remove the call as well as the 'ret' variable which was only ever
equal to 'nclients' at the point when we returned the value.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-08-06 08:53:26 +02:00
Peter Krempa
98f6f2081d util: alloc: Reimplement VIR_APPEND_ELEMENT using virAppendElement
Use virAppendElement instead of virInsertElementsN to implement
VIR_APPEND_ELEMENT which allows us to remove error handling as the
only relevant errors were removed when switching to aborting memory
allocation functions.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-08-06 08:53:25 +02:00
Peter Krempa
92a3eddd03 Remove static analysis assertions
None of them are currently needed to pass our upstream CI, most were
either for ancient clang versions or coverity for silencing false
positives.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-05-24 20:26:20 +02:00
Michal Privoznik
c8238579fb lib: Drop internal virXXXPtr typedefs
Historically, we declared pointer type to our types:

  typedef struct _virXXX virXXX;
  typedef virXXX *virXXXPtr;

But usefulness of such declaration is questionable, at best.
Unfortunately, we can't drop every such declaration - we have to
carry some over, because they are part of public API (e.g.
virDomainPtr). But for internal types - we can do drop them and
use what every other C project uses 'virXXX *'.

This change was generated by a very ugly shell script that
generated sed script which was then called over each file in the
repository. For the shell script refer to the cover letter:

https://listman.redhat.com/archives/libvir-list/2021-March/msg00537.html

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2021-04-13 17:00:38 +02:00
Jiri Denemark
7d2fd6ef01 Do not check return value of VIR_EXPAND_N
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2021-03-22 12:44:18 +01:00
Kristina Hanicova
155151a3d0 Use g_steal_pointer where possible
Via coccinelle (not the handbag!)
spatches used:
@ rule1 @
identifier a, b;
symbol NULL;
@@

- b = a;
  ... when != a
- a = NULL;
+ b = g_steal_pointer(&a);

@@

- *b = a;
  ... when != a
- a = NULL;
+ *b = g_steal_pointer(&a);

Signed-off-by: Kristina Hanicova <khanicov@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2021-03-01 15:54:42 +01:00
Peter Krempa
6431b20c3e virJSONValueArrayAppend: Clear pointer when taking ownership of passed value
The parent array takes ownership of the inserted value once all checks
pass. Don't make the callers second-guess when that happens and modify
the function to take a double pointer so that it can be cleared once the
ownership is taken.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-02-20 13:26:37 +01:00
Peter Krempa
5fc3892891 virJSONValueObjectAppend: Clear pointer when taking ownership of passed value
The parent object takes ownership of the inserted value once all checks
pass. Don't make the callers second-guess when that happens and modify
the function to take a double pointer so that it can be cleared once the
ownership is taken.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-02-20 13:26:37 +01:00
Peter Krempa
49efa299b5 virNetServerPreExecRestart: Refactor memory cleanup
Switch to using the 'g_auto*' helpers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-02-20 13:26:36 +01:00
Peter Krempa
6e35dc7bbe virNetServerPreExecRestart: Drop error reporting from virJSONValueObjectAppend* calls
The functions report errors already and the error can nowadays only
happen on programmer errors (if the passed virJSONValue isn't an
object), which won't happen. Remove the reporting.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-02-20 13:26:36 +01:00
Laine Stump
a2182cf871 rpc: replace VIR_FREE with g_free in all *Dispose() functions
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2021-02-05 00:22:09 -05:00
Ján Tomko
71ec40e917 rpc: use g_new0 instead of VIR_ALLOC
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-10-01 17:32:15 +02:00
Nikolay Shirokovskiy
b776dfa8e8 rpc: add shutdown facilities to netserver
virNetServerClose and virNetServerShutdownWait are used to start net server
threads shutdown and wait net server threads to actually finish respectively
during net daemon shutdown procedure.

Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2020-09-07 09:33:59 +03:00
Michal Privoznik
c0a3088094 src: Fix boolean assignment
In a few places we use 0 and false, or 1 and true interchangeably
even though the variable or return type in question is boolean.
Fix those places.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2020-05-05 13:08:57 +02:00
Michal Privoznik
1baead31fa virnetserver: Check for virNetServerClientInitKeepAlive() retval
Since it's introduction in v0.9.7-147-gf4324e3292 the
virNetServerClientInitKeepAlive() function returned nothing than
a negative one. Fortunately, this did not pose any problem
because we ignored the retval happily. Well, it's time to check
for the retval because the function might fail regularly.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2020-05-05 13:08:34 +02:00
Zhang Bo
15d280fa97 virnetserver: Introduce virNetServerUpdateTlsFiles
Add an API to update server's tls context.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Zhang Bo <oscar.zhangbo@huawei.com>
Signed-off-by: Wu Qingliang <wuqingliang4@huawei.com>
2020-03-13 17:07:32 +00:00
Daniel P. Berrangé
5bff668dfb src: improve thread naming with human targetted names
Historically threads are given a name based on the C function,
and this name is just used inside libvirt. With OS level thread
naming this name is now visible to debuggers, but also has to
fit in 15 characters on Linux, so function names are too long
in some cases.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-03-05 12:23:04 +00:00
Peter Krempa
e9153cc604 util: json: Convert virJSONValueNewObject() to g_new0
Make it obvious that the function always returns a valid pointer and fix
all callers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2020-03-05 11:31:38 +01:00
Peter Krempa
d69470a18a virJSONValueNewArray: Use g_new0 to allocate and remove NULL checks from callers
Use the glib allocation function that never returns NULL and remove the
now dead-code checks from all callers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-02-04 13:45:33 +01:00
Marc Hartmayer
c306873841 rpc: Introduce virNetServerGetProgramLocked helper function
This patch introduces virNetServerGetProgramLocked. It's a function to
determine which program has to be used for a given @msg. This function
will be reused in the next patch.

Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
2019-12-13 14:41:55 -05:00
Marc Hartmayer
a5493c47a0 rpc: use the return value of virObjectRef directly
Use the return value of virObjectRef directly. This way, it's easier
for another reader to identify the reason why the additional reference
is required.

Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
2019-12-13 14:37:00 -05:00
Daniel Henrique Barboza
2d13431d45 rpc: remove unneeded cleanup labels
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-11-12 17:54:01 +01:00
Ján Tomko
45bf10ba1d rpc: use g_strdup instead of VIR_STRDUP
Replace all occurrences of
  if (VIR_STRDUP(a, b) < 0)
     /* effectively dead code */
with:
  a = g_strdup(b);

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-21 12:51:58 +02:00
Daniel P. Berrangé
49fa9e64ca rpc: add API for checking whether an auth scheme is in use on a server
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-12 16:55:40 +01:00
Daniel P. Berrangé
9692fe10eb rpc: add helper APIs for adding services with systemd activation
Currently code has to first create the service and then separately
register it with the server. If the socket associated with a particular
service is not passed from systemd we want to skip creating the service
altogether. This means we can't put the systemd activation logic into
the constructors for virNetServerService.

This patch thus creates some helper methods against virNetServer which
combine systemd activation, service creation and service registration
into one single operation. This operation is automatically a no-op if
systemd activation is present and no sockets were passed in.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-12 16:55:39 +01:00
Daniel P. Berrangé
5a148ce846 remote: delete the avahi mDNS support
Libvirtd has long had integration with avahi for advertising libvirtd
using mDNS when TCP/TLS listening is enabled. For a long time the
virt-manager application had support for auto-detecting libvirtds
on the local network using mDNS, but this was removed last year

  commit fc8f8d5d7e3ba80a0771df19cf20e84a05ed2422
  Author: Cole Robinson <crobinso@redhat.com>
  Date:   Sat Oct 6 20:55:31 2018 -0400

    connect: Drop avahi support

    Libvirtd can advertise itself over avahi. The feature is disabled by
    default though and in practice I hear of no one actually using it
    and frankly I don't think it's all that useful

    The 'Open Connection' wizard has a disproportionate amount of code
    devoted to this feature, but I don't think it's useful or worth
    maintaining, so let's drop it

I've never heard of any other applications having support for using
mDNS to detect libvirtd instances. Though it is theoretically possible
something exists out there, it is clearly going to be a niche use case
in the virt ecosystem as a whole.

By removing avahi integration we can cut down the dependency chain for
the basic libvirtd install and reduce our code maint burden.

Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-06-21 12:59:42 +01:00
Michal Privoznik
aa308f7ffc virNetServerPreExecRestart: Check for retval of virJSONValueNewArray()
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-05-14 15:56:45 +02:00
Cole Robinson
af36f8a641 Require a semicolon for VIR_ONCE_GLOBAL_INIT calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>). VIR_ONCE_GLOBAL_INIT is almost
exclusively called without an ending semicolon, but let's
standardize on using one like the other macros.

Add a dummy struct definition at the end of the macro, so
the compiler will require callers to add a semicolon.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
Marc Hartmayer
7330d0918e rpc: Initialize a worker pool for max_workers=0 as well
Semantically, there is no difference between an uninitialized worker
pool and an initialized worker pool with zero workers. Let's allow the
worker pool to be initialized for max_workers=0 as well then which
makes the API more symmetric and simplifies code. Validity of the
worker pool is delegated to virThreadPoolGetMaxWorkers instead.

This patch fixes segmentation faults in
virNetServerGetThreadPoolParameters and
virNetServerSetThreadPoolParameters for the case when no worker pool
is actually initialized (max_workers=0).

Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
2018-08-14 12:16:42 -04:00
Marc Hartmayer
45e00c7f2d rpc: Fix deadlock if there is no worker pool available
@srv must be unlocked for the call virNetServerProcessMsg otherwise a
deadlock can occur.

Since the pointer 'srv->workers' will never be changed after
initialization and the thread pool has it's own locking we can release
the lock of 'srv' earlier. This also fixes the deadlock.

Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: Bjoern Walk <bwalk@linux.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-07-21 07:46:42 -04:00
Michal Privoznik
234ce7d02f src: Drop most of #ifdef WITH_GNUTLS
Now that GnuTLS is a requirement, we can drop a lot of
conditionally built code. However, not all ifdef-s can go because
we still want libvirt_setuid to build without gnutls.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-06-05 14:32:36 +02:00
John Ferlan
4a3d6ed5ee util: Clean up consumers of virJSONValueArraySize
Rather than have virJSONValueArraySize return a -1 when the input
is not an array and then splat an error message, let's check for
an array before calling and then change the return to be a size_t
instead of ssize_t.

That means using the helper virJSONValueIsArray as well as using a
more generic error message such as "Malformed <something> array".
In some cases we can remove stack variables and when we cannot,
those variables should be size_t not ssize_t. Alter a few references
of if (!value) to be if (value == 0) instead as well.

Some callers can already assume an array is being worked on based
on the previous call, so there's less to do.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-05-10 14:59:15 -04:00
Michal Privoznik
10f94828ea virobject: Introduce VIR_CLASS_NEW() macro
So far we are repeating the following lines over and over:

  if (!(virSomeObjectClass = virClassNew(virClassForObject(),
                             "virSomeObject",
                             sizeof(virSomeObject),
                             virSomeObjectDispose)))
      return -1;

While this works, it is impossible to do some checking. Firstly,
the class name (the 2nd argument) doesn't match the name in the
code in all cases (the 3rd argument). Secondly, the current style
is needlessly verbose. This commit turns example into following:

  if (!(VIR_CLASS_NEW(virSomeObject,
                      virClassForObject)))
      return -1;

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-04-18 10:04:55 +02:00
Daniel P. Berrangé
86cae503a4 rpc: avoid crashing in pre-exec if no workers are present
If max_workers is set to zero, then the worker thread pool won't be
created, so when serializing state for pre-exec we must set various
parameters to zero.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Jim Fehlig <jfehlig@suse.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-08 15:40:29 +00:00
Daniel P. Berrangé
c6f1d5190b rpc: simplify calling convention of virNetServerClientDispatchFunc
Currently virNetServerClientDispatchFunc implementations are only
responsible for free'ing the "msg" parameter upon success. Simplify the
calling convention by making it their unconditional responsibility to
free the "msg", and close the client if desired.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Jim Fehlig <jfehlig@suse.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-08 15:40:29 +00:00
Daniel P. Berrangé
464889fff8 rpc: push ref acquisition into RPC dispatch function
There's no reason why the virNetServerClientDispatchRead method needs to
acquire an extra reference on the "client" object. An extra reference is
only needed if the registered dispatch callback is going to keep hold of
the "client" for work in the background. Thus we can push reference
acquisition into virNetServerDispatchNewMessage.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Jim Fehlig <jfehlig@suse.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-08 15:40:29 +00:00
John Ferlan
a8ef7b69dc netserver: Remove ServiceToggle during ServerDispose
No sense in calling ServiceToggle for all nservices during
ServiceDispose since ServerClose calls ServiceClose which
removes the IOCallback that's being toggled via ServiceToggle.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-02-02 18:01:00 -05:00
Daniel P. Berrange
b41780e47a rpc: pass virNetServer to post-exec restart callback in typesafe manner
The virNetServer class is passing a pointer to itself to the
virNetServerClient as a 'void *' pointer. This is presumably due to fact
that the virnetserverclient.h file doesn't see the virNetServerPtr
typedef. The typedef is easily movable though, which lets us get
typesafe parameter passing, removing the confusion of passing two
distinct 'void *' pointers to one method.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-01-31 15:15:25 +00:00
Marc Hartmayer
94bbbcee1f rpc: virnetserver: Fix race on srv->nclients_unauth
There is a race between virNetServerProcessClients (main thread) and
remoteDispatchAuthList/remoteDispatchAuthPolkit/remoteSASLFinish (worker
thread) that can lead to decrementing srv->nclients_unauth when it's
zero. Since virNetServerCheckLimits relies on the value
srv->nclients_unauth the underrun causes libvirtd to stop accepting
new connections forever.

Example race scenario (assuming libvirtd is using policykit and the
client is privileged):
  1. The client calls the RPC remoteDispatchAuthList =>
     remoteDispatchAuthList is executed on a worker thread (Thread
     T1). We're assuming now the execution stops for some time before
     the line 'virNetServerClientSetAuth(client, 0)'
  2. The client closes the connection irregularly. This causes the
     event loop to wake up and virNetServerProcessClient to be
     called (on the main thread T0). During the
     virNetServerProcessClients the srv lock is hold. The condition
     virNetServerClientNeedAuth(client) will be checked and as the
     authentication is not finished right now
     virNetServerTrackCompletedAuthLocked(srv) will be called =>
     --srv->nclients_unauth => 0
  3. The Thread T1 continues, marks the client as authenticated, and
     calls virNetServerTrackCompletedAuthLocked(srv) =>
     --srv->nclients_unauth => --0 => wrap around as nclient_unauth is
     unsigned
  4. virNetServerCheckLimits(srv) will disable the services forever

To fix it, add an auth_pending field to the client struct so that it
is now possible to determine if the authentication process has already
been handled for this client.

Setting the authentication method to none for the client in
virNetServerProcessClients is not a proper way to indicate that the
counter has been decremented, as this would imply that the client is
authenticated.

Additionally, adjust the existing test cases for this new field.

Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
2018-01-04 06:55:31 -05:00
Marc Hartmayer
f1d8251972 rpc: Introduce virNetServerSetClientAuthenticated
Combine virNetServerClientSetAuth(client,
VIR_NET_SERVER_SERVICE_AUTH_NONE) and virNetServerTrackCompletedAuth
into one new function named virNetServerSetClientAuthenticated.

After using this new function the function
virNetServerTrackCompletedAuth was superfluous and is therefore
removed. In addition, it is not very common that a
'{{function}}' (virNetServerTrackCompletedAuth) does more than just
the locking compared to
'{{function}}Locked' (virNetServerTrackCompletedAuthLocked).

virNetServerTrackPendingAuth was already superfluous and therefore
it's also removed.

Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: Stefan Zimmermann <stzi@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-01-04 06:55:31 -05:00
Marc Hartmayer
0eaa59dce1 rpc: Correct locking and simplify the function
The lock for @client must not only be held for the duration of
checking whether the client wants to close, but also for as long as
we're closing the client. The same applies to the tracking of
authentications.

Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
2018-01-04 06:55:31 -05:00
Cédric Bosdonnat
2089ab2112 netserver: close clients before stopping all drivers
So far clients were closed when disposing the daemon, after the state
driver cleanup. This was leading to libvirtd crashing at shutdown due
to missing driver.

Moving the client close in virNetServerClose() fixes the problem.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
2017-12-21 13:17:26 +01:00
Guido Günther
cdecfbed02 virnetserver: fix mesage vs message typo 2017-09-11 18:17:22 +02:00