If a client is in the process of being closed down, then its client->osPrivate
pointer will be set to NULL by CloseDownConnection. This can cause a crash if
freeing the client's resources results in a call to AttendClient. For example,
if the client has a pending sync fence:
Thread 1 "X" received signal SIGSEGV, Segmentation fault.
AttendClient (client=0x5571c4aed9a0) at ../os/connection.c:942
(gdb) bt
#0 AttendClient (client=0x5571c4aed9a0) at ../os/connection.c:942
#1 0x00005571c3dbb865 in SyncAwaitTriggerFired (pTrigger=<optimized out>) at ../Xext/sync.c:694
#2 0x00005571c3dd5749 in miSyncDestroyFence (pFence=0x5571c5063980) at ../miext/sync/misync.c:120
#3 0x00005571c3dbbc69 in FreeFence (obj=<optimized out>, id=<optimized out>) at ../Xext/sync.c:1909
#4 0x00005571c3d7a01d in doFreeResource (res=0x5571c506e3d0, skip=skip@entry=0) at ../dix/resource.c:880
#5 0x00005571c3d7b1dc in FreeClientResources (client=0x5571c4aed9a0) at ../dix/resource.c:1146
#6 FreeClientResources (client=0x5571c4aed9a0) at ../dix/resource.c:1109
#7 0x00005571c3d5525f in CloseDownClient (client=0x5571c4aed9a0) at ../dix/dispatch.c:3473
#8 0x00005571c3d55eeb in Dispatch () at ../dix/dispatch.c:492
#9 0x00005571c3d59e96 in dix_main (argc=3, argv=0x7ffe7854bc28, envp=<optimized out>) at ../dix/main.c:276
#10 0x00007fea4837cb6b in __libc_start_main (main=0x5571c3d1d060 <main>, argc=3, argv=0x7ffe7854bc28, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffe7854bc18) at ../csu/libc-start.c:308
#11 0x00005571c3d1d09a in _start () at ../Xext/sync.c:2378
(gdb) print client->osPrivate
$1 = (void *) 0x0
Since the client is about to be freed, its ignore count doesn't matter and
AttendClient can simply be a no-op. Check for client->clientGone in AttendClient
and remove similar checks from two callers that had them.
Signed-off-by: Aaron Plattner <aplattner@nvidia.com>
It can take some time for Xorg to start. If Xorg runs as a systemd
service and other services are based on it, they have no way to
determine when Xorg is really ready to accept requests. Let's use
sd_notify() provided by libsystemd to signal systemd for readiness.
If Xorg has not been started as a systemd service, this won't do
anything.
Signed-off-by: Topi Miettinen <toiwoton@gmail.com>
This contortion made a bit more sense before we got SetNotifyFd and
friends, but now there's no need for it.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
This variable was no longer being read anywhere. MAXCLIENTS the macro is
the compile-time maximum limit, LIMITCLIENTS the macro is the default
limit, LimitClients the variable is the limit for the current server.
Signed-off-by: Adam Jackson <ajax@redhat.com>
This ensures that we don't use the now-closed file descriptor in the
future.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
In set_poll_client, check oc->trans_conn to make sure the connection
is still running before changing the ospoll configuration of the file
descriptor in case some other bit of the server is now using this file
descriptor.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
AbortClient performs most of the same operations as
CloseDownFileDescriptor except that it doesn't call ospoll_remove,
leaving that unaware that the file descriptor has been closed.
If the file descriptor is re-used before the server comes back around
to clean up, and that new file descriptor is passed to SetNotifyFd,
then that function will mistakenly re-interpret the stale ClientPtr
returned by ospoll_data as a struct notify * instead and mangle data
badly.
To fix this, the patch does:
1) Change CloseDownFileDescriptor so that it can be called multiple
times on the same OsCommPtr. The calls related to the file
descriptor are moved inside the check for trans_conn and
oc->trans_conn is set to NULL after cleaning up.
2) Move the XdmcpCloseDisplay call into CloseDownFileDescriptor. I
don't think the actually matters as we just need to know at some
point that the session client has exited. Moving it avoids the
possibility of having this accidentally trigger from another client
with the same fd which closes down at around the same time.
3) Change AbortClient to call CloseDownFileDescriptor. This makes sure
that all of the fd-related clean up happens in the same way
everywhere, in particular ensures that ospoll is notified about the
closed file descriptor at the time it is closed and not some time later.
Debian-bug: https://bugs.debian.org/862824
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
This infrastructure is no longer read, only written; the mapping
from fd to client is now handled by ospoll.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
A client which is attended while a grab is blocking execution of its
requests needs to be placed in the saved_ready_clients list so that it
will get scheduled once the grab terminates. Otherwise, if the client
never sends another request, there is no way for it to be placed in
the ready_clients list.
v2: Wrap comment above mark_client_saved_ready.
Remove test for OS_COMM_IGNORED which will always be true.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99333
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
This change has two effects:
1. Only calls FlushCallbacks when we're actually flushing data to a
client. The unnecessary FlushCallback calls could cause significant
performance degradation with compositing, which is significantly
reduced even without any driver changes.
2. By passing the ClientPtr to FlushCallbacks, drivers can completely
eliminate unnecessary flushing of GPU commands by keeping track of
whether we're flushing any XDamageNotify events to the client for
which the corresponding rendering commands haven't been flushed to
the GPU yet.
Reviewed-by: Adam Jackson <ajax@redha.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
poll provides per-fd notification of failure, so we don't need
CheckConnections anymore.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
With no code depending on the range of file descriptors, checking
for that can be eliminated.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Eliminates all of the fd_set mangling in the server main thread
v2: Listen for POLLOUT while writes are blocked.
v3: Only mark client not ready on EAGAIN return from read
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
This converts the dispatch loop into using a list of ready clients
instead of an array. This changes the WaitForSomething API so that it
notifies DIX when a client becomes ready to read, instead of returning
the set of ready clients.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
All uses of these interfaces should instead be using the NotifyFd API
instead.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Instead of open-coding a single FD wait, use NotifyFd to wait for the
FD to become readable before returning the error message.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Removed from xtrans in 2012, and never wired up in the modular build
anyway.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Alan Coopersmith <alan.coopersmith@oracle.com>
When -displayfd is looping through the possible display ids to use,
if it can't open all the listening sockets for one (say when :0 is
already in use), it calls CloseWellKnownConnections to close all
the ListenTransConns entries before the point that ListenTransFds
was allocated & initialized, so CloseWellKnownConnections would
segfault trying to read entries from a NULL ListenTransFds pointer.
Introduced by commit 7b02f0b8
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Keith Packard <keithp@keithp.com>
Fixes https://bugs.freedesktop.org/show_bug.cgi?id=93212
Previously all X servers started with -displayfd would overwrite
Xorg.0.log - now a temporary name of Xorg.pid-<pid>.log is used
until after -displayfd finds an open display - then it is renamed
to the traditional Xorg.<display>.log name.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Replace the custom path for dealing with new incoming connections with
the general-purpose NotifyFd API.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
This adds the ability to be notified when a file descriptor is
available for writing.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
This provides a callback-based interface to monitor file
descriptors beyond the usual client and device interfaces.
Modules within the server using file descriptors for reading and/or
writing can call
Bool SetNotifyFd(int fd, NotifyFdProcPtr notify_fd, int mask, void *data);
mask can be any combination of X_NOTIFY_READ and X_NOTIFY_WRITE.
When 'fd' becomes readable or writable, the notify_fd function will be
called with the 'fd', the ready conditions and 'data' values as arguments,
When the module no longer needs to monitor the fd, it will call
void RemoveNotifyFd(int fd);
RemoveNotifyFd may be called from the notify function.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Make the maximum number of clients user configurable, either from the command
line or from xorg.conf
This patch works by using the MAXCLIENTS (raised to 512) as the maximum
allowed number of clients, but allowing the actual limit to be set by the
user to a lower value (keeping the default of 256).
There is a limit size of 29 bits to be used to store both the client ID and
the X resources ID, so by reducing the number of clients allowed to connect to
the X server, the user can increase the number of X resources per client or
vice-versa.
Parts of this patch are based on a similar patch from Adam Jackson
<ajax@redhat.com>
This now requires at least xproto 7.0.28
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Since _XSERVTransClose frees the connection pointer passed to it,
remove that pointer from the array, so we don't try to double free it
if we come back into CloseWellKnownConnections again.
Should fix https://bugzilla.yoctoproject.org/show_bug.cgi?id=6665 in which
the shutdown section of the main() loop called CloseWellKnownConnections()
and then moved on to ddxGiveUp(), which failed to release the VT and thus
called AbortServer(), which called CloseWellKnownConnections() again.
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Use typedefs to work around dtrace dropping const qualifiers from probe
arguments when generating Xserver-dtrace.h. Add new probes.h header to
avoid having to replicate these typedefs in every file with dtrace probes.
Gets rid of these warnings from gcc 4.8:
getevents.c:1096:9:
warning: passing argument 6 of '__dtrace_Xserver___input__event' discards
'const' qualifier from pointer target type [enabled by default]
getevents.c:1096:9:
warning: passing argument 7 of '__dtrace_Xserver___input__event' disards
'const' qualifier from pointer target type [enabled by default]
getevents.c:1651:9:
warning: passing argument 6 of '__dtrace_Xserver___input__event' disards
'const' qualifier from pointer target type [enabled by default]
getevents.c:1651:9:
warning: passing argument 7 of '__dtrace_Xserver___input__event' disards
'const' qualifier from pointer target type [enabled by default]
getevents.c:1791:9:
warning: passing argument 6 of '__dtrace_Xserver___input__event' disards
'const' qualifier from pointer target type [enabled by default]
getevents.c:1791:9:
warning: passing argument 7 of '__dtrace_Xserver___input__event' disards
'const' qualifier from pointer target type [enabled by default]
getevents.c:1921:9:
warning: passing argument 6 of '__dtrace_Xserver___input__event' disards
'const' qualifier from pointer target type [enabled by default]
getevents.c:1921:9:
warning: passing argument 7 of '__dtrace_Xserver___input__event' disards
'const' qualifier from pointer target type [enabled by default]
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
-displayfd should check ports up to 65535
Noticed during https://cygwin.com/ml/cygwin-xfree/2014-07/msg00024.html
Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
pharris says that the resets should not be done in the hotplugging case.
This may fix a crash reported against XQuartz:
http://xquartz.macosforge.org/trac/ticket/869
Signed-off-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com>
Reviewed-by: Peter Harris <pharris@opentext.com>
When the server is started with the -displayfd option, check to make
sure that the writes succeed and give up running if they don't.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>
Failing to clear this means that we'll attempt to write the display
number to a random file descriptor on subsequent X server generations.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>
Handle -displayfd and an explicit display number sensibly, e.g. use the
explicitly specified display number, and write it to the displayfd
v2: displayfd might be 0, so use -1 as invalid value
v3: Rebase for addition of NoListenAll flag
Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
When the Xwayland server is socket-activated, we need to connect and
initialize the window manager before the activating client gets to
proceed with connecting. We do this by passing a socket file
descriptor for the window manager connection to the Xwayland server,
which then uses this new function to set it up as an X client.
Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
A socket-activated server will receive its listening sockets from the
parent process and should not create its own sockets. This patch
introduces a NoListen flag that can be set by a DDX to prevent
the server from creating the sockets. When NoListen is enabled, we
also disable the server lock checking, since the parent process is
responsible for checking the lock before picking the display name and
creating the sockets.
Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
This function was written to allow the X server to inherit the listen
socket from launchd on OS X. The code is not specific to OS X though
and will be useful for on-demand launched Xwayland servers.
Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
This lets us stop using the 'pointer' typedef in Xdefs.h as 'pointer'
is used throughout the X server for other things, and having duplicate
names generates compiler warnings.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Forwarding proxies like sshd will appear to be local, even though they
aren't really. This leads to weird behaviour for extensions that truly
require running under the same OS services as the client, like MIT-SHM
and DRI2.
Add two new legal values for the initial connection's byteOrder field,
'r' and 'R'. These act like 'l' and 'B' respectively, but have the side
effect of forcing the client to be treated as non-local. Forwarding
proxies should attempt to munge the first packet of the connection
accordingly; older servers will reject connections thusly munged, so the
proxy should fall back to passthrough if the munged connection attempt
fails.
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Keith Packard <keithp@keithp.com>
Tested-by: Daniel Stone <daniel@fooishbar.org>
Much easier for scripts that try to read the display value off the file
descriptor. Plus, this restores the behaviour we had for this patch in
Fedora since server 1.6 (April 2009).
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Chase Douglas <chase.douglas@canonical.com>
This option specifies a file descriptor in the launching process. X
will scan for an available display number and write that number back to
the launching process, at the same time as SIGUSR1 generation. This
means display managers don't need to guess at available display numbers.
As a consequence, if X fails to start when using -displayfd, it's not
because the display was in use, so there's no point in retrying the X
launch on a higher display number.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Chase Douglas <chase.douglas@canonical.com>
Reviewed-by: Julien Cristau <jcristau@debian.org>
Tested-by: Julien Cristau <jcristau@debian.org>
Reviewed-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
This is strictly the application of the script 'x-indent-all.sh'
from util/modular. Compared to the patch that Daniel posted in
January, I've added a few indent flags:
-bap
-psl
-T PrivatePtr
-T pmWait
-T _XFUNCPROTOBEGIN
-T _XFUNCPROTOEND
-T _X_EXPORT
The typedefs were needed to make the output of sdksyms.sh match the
previous output, otherwise, the code is formatted badly enough that
sdksyms.sh generates incorrect output.
The generated code was compared with the previous version and found to
be essentially identical -- "assert" line numbers and BUILD_TIME were
the only differences found.
The comparison was done with this script:
dir1=$1
dir2=$2
for dir in $dir1 $dir2; do
(cd $dir && find . -name '*.o' | while read file; do
dir=`dirname $file`
base=`basename $file .o`
dump=$dir/$base.dump
objdump -d $file > $dump
done)
done
find $dir1 -name '*.dump' | while read dump; do
otherdump=`echo $dump | sed "s;$dir1;$dir2;"`
diff -u $dump $otherdump
done
Signed-off-by: Keith Packard <keithp@keithp.com>
Acked-by: Daniel Stone <daniel@fooishbar.org>
Acked-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Move some constants near their only users, and remove some
getdtablesize() logic that's second-guessing configure.
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
Signed-off-by: Adam Jackson <ajax@redhat.com>
