Go to file
Alan Coopersmith 73b2660d72 Avoid use-after-free in dix/dixfonts.c: doImageText() [CVE-2013-4396]
Save a pointer to the passed in closure structure before copying it
and overwriting the *c pointer to point to our copy instead of the
original.  If we hit an error, once we free(c), reset c to point to
the original structure before jumping to the cleanup code that
references *c.

Since one of the errors being checked for is whether the server was
able to malloc(c->nChars * itemSize), the client can potentially pass
a number of characters chosen to cause the malloc to fail and the
error path to be taken, resulting in the read from freed memory.

Since the memory is accessed almost immediately afterwards, and the
X server is mostly single threaded, the odds of the free memory having
invalid contents are low with most malloc implementations when not using
memory debugging features, but some allocators will definitely overwrite
the memory there, leading to a likely crash.

Reported-by: Pedro Ribeiro <pedrib@gmail.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Julien Cristau <jcristau@debian.org>
2013-10-14 17:56:44 -07:00
composite damage: Simplify DamageUnregister 2013-09-10 14:28:35 -04:00
config xserver: enable InputClass option "GrabDevice" by default for non-seat0 seats (#69478) 2013-09-25 03:52:54 +10:00
damageext Merge remote-tracking branch 'ajax/xserver-next' 2013-10-04 13:50:04 -07:00
dbe dbe: Fold the window private private into the window private 2013-09-10 13:28:24 -04:00
dix Avoid use-after-free in dix/dixfonts.c: doImageText() [CVE-2013-4396] 2013-10-14 17:56:44 -07:00
doc doc: Update documentation about Windows platforms support a bit 2012-10-29 12:21:14 +00:00
exa Skip damage calls if DamageCreate fails in exa functions 2013-10-14 17:56:44 -07:00
fb fb: Remove unused compatibility wrappers 2013-09-10 13:29:21 -04:00
glx glx: Fill in some missing attributes from DoGetFBConfigs 2013-09-11 14:37:33 -04:00
hw Update GLX dependencies now that DRI & DRI2 are builtins, not modules 2013-10-14 17:56:44 -07:00
include include: change grabtypes to start at 1 2013-10-14 11:07:37 +10:00
m4 XORG_TLS: Pick the first option that works (ie: prefer __thread) 2013-02-14 09:20:47 -08:00
man Correct description of -displayfd option in man page. 2012-10-11 12:53:57 +01:00
mi damage: Simplify DamageUnregister 2013-09-10 14:28:35 -04:00
miext rootless: Use miCopyRegion instead of fbCopyRegion 2013-10-06 09:18:15 -07:00
os os: move <arpa/inet.h> for any !win32 system 2013-10-05 15:26:55 +02:00
pseudoramiX Move pseudoramiX code where it can be shared between Xwin and Xquartz 2013-08-30 12:52:30 +01:00
randr randr: Fix a copypasta bug in CRTC confinement 2013-09-10 13:26:25 -04:00
record Move extension initialisation prototypes into extinit.h 2012-07-09 23:06:41 -07:00
render Abstract cursor refcounting 2013-05-15 19:17:57 +10:00
test test: add new os executable to .gitignore 2013-09-25 03:52:54 +10:00
Xext dix: FIXES is not optional 2013-09-10 13:28:24 -04:00
xfixes Abstract cursor refcounting 2013-05-15 19:17:57 +10:00
Xi Xi: allow for XIAllowEvent requests larger than XI < 2.2 size (#68554) 2013-08-30 14:26:55 +10:00
xkb xkb: don't call atoi(NULL) when parsing argv 2013-07-02 15:12:29 +10:00
.dir-locals.el Add .dir-locals.el 2013-08-17 12:17:36 +02:00
.gitignore doc: relocate xserver.ent in the package root directory 2011-05-14 11:22:26 -07:00
autogen.sh autogen.sh: Honor NOCONFIGURE=1 2012-10-19 13:12:33 +10:00
configure.ac configure.ac: Include missing proto declarations in SDK_REQUIRED_MODULES 2013-10-07 11:20:58 -07:00
COPYING Shadow: Switch the Amiga/Atari bitplane code to the canonical X.Org license 2013-05-14 14:41:00 -07:00
devbook.am devbook.am: maintenance update from docbook.am 2011-09-21 14:07:52 -07:00
docbook.am docbook.am: embed css styles inside the HTML HEAD element 2011-09-21 14:07:49 -07:00
fix-miregion Change region implementation names to eliminate the 'mi' prefix 2010-06-05 17:47:32 -07:00
fix-miregion-private Change region implementation names to eliminate the 'mi' prefix 2010-06-05 17:47:32 -07:00
fix-patch-whitespace Rename region macros to eliminate screen argument 2010-06-05 18:59:00 -07:00
fix-region Rename region macros to eliminate screen argument 2010-06-05 18:59:00 -07:00
Makefile.am Move pseudoramiX code where it can be shared between Xwin and Xquartz 2013-08-30 12:52:30 +01:00
manpages.am Xdmx.man: Show actual configured XKB defaults instead of old hardcoded values 2011-06-21 17:54:14 -07:00
README packaging: provide a default README file #24206 2010-01-27 14:00:17 -08:00
xorg-server.m4 macros: clarify documentation 2012-11-05 13:24:57 -06:00
xorg-server.pc.in xfree86: link modules against Xorg symbols on Cygwin 2012-04-05 21:57:07 -05:00
xserver.ent.in doc: relocate xserver.ent in the package root directory 2011-05-14 11:22:26 -07:00

					X Server

The X server accepts requests from client applications to create windows,
which are (normally rectangular) "virtual screens" that the client program
can draw into.

Windows are then composed on the actual screen by the X server
(or by a separate composite manager) as directed by the window manager,
which usually communicates with the user via graphical controls such as buttons
and draggable titlebars and borders.

For a comprehensive overview of X Server and X Window System, consult the
following article:
http://en.wikipedia.org/wiki/X_server

All questions regarding this software should be directed at the
Xorg mailing list:

        http://lists.freedesktop.org/mailman/listinfo/xorg

Please submit bug reports to the Xorg bugzilla:

        https://bugs.freedesktop.org/enter_bug.cgi?product=xorg

The master development code repository can be found at:

        git://anongit.freedesktop.org/git/xorg/xserver

        http://cgit.freedesktop.org/xorg/xserver

For patch submission instructions, see:

	http://www.x.org/wiki/Development/Documentation/SubmittingPatches

For more information on the git code manager, see:

        http://wiki.x.org/wiki/GitPage