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Peter Hutterer 564ccf2ce9 mi: reset the PointerWindows reference on screen switch
PointerWindows[] keeps a reference to the last window our sprite
entered - changes are usually handled by CheckMotion().

If we switch between screens via XWarpPointer our
dev->spriteInfo->sprite->win is set to the new screen's root window.
If there's another window at the cursor location CheckMotion() will
trigger the right enter/leave events later. If there is not, it skips
that process and we never trigger LeaveWindow() - PointerWindows[] for
the device still refers to the previous window.

If that window is destroyed we have a dangling reference that will
eventually cause a use-after-free bug when checking the window hierarchy
later.

To trigger this, we require:
- two protocol screens
- XWarpPointer to the other screen's root window
- XDestroyWindow before entering any other window

This is a niche bug so we hack around it by making sure we reset the
PointerWindows[] entry so we cannot have a dangling pointer. This
doesn't handle Enter/Leave events correctly but the previous code didn't
either.

CVE-2023-5380, ZDI-CAN-21608

This vulnerability was discovered by:
Sri working with Trend Micro Zero Day Initiative

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Adam Jackson <ajax@redhat.com>
2023-10-25 00:37:47 +00:00
.gitlab-ci xwayland: Add XTEST support using EIS 2023-06-26 13:19:19 +02:00
Xext xtest: Check whether there is a sendEventsProc to call 2023-09-04 11:08:42 +02:00
Xi Xi/randr: fix handling of PropModeAppend/Prepend 2023-10-25 00:32:52 +00:00
composite composite: Expose CompositeIsImplicitRedirectException 2023-07-18 09:34:39 +00:00
config config: add a quirk for Apple Silicon appledrm 2023-01-11 10:01:29 +00:00
damageext Remove autotools support 2021-10-27 13:15:40 +03:00
dbe Remove autotools support 2021-10-27 13:15:40 +03:00
dix mi: reset the PointerWindows reference on screen switch 2023-10-25 00:37:47 +00:00
doc Remove autotools support 2021-10-27 13:15:40 +03:00
dri3 dri3: Don't compute intersection with drawable modifiers 2023-01-20 17:56:54 +00:00
exa rootless: Use screen_x and screen_y instead of pixmap pointer hacks 2023-01-20 17:10:54 +00:00
fb Revert "fb: Remove even/odd tile slow-pathing" 2023-04-19 15:33:59 +00:00
glamor glamor: accelerate incomplete textures for GL ES 2023-10-20 14:09:57 +03:00
glx GLX: Free the tag of the old context later 2022-12-09 15:10:09 +00:00
hw Extented 'arm' case to 'aarch64' on BSD. 2023-10-22 16:08:21 +00:00
include mi: reset the PointerWindows reference on screen switch 2023-10-25 00:37:47 +00:00
m4 Add ax_pthread.m4 to m4/ 2016-05-29 19:20:51 -07:00
man Disallow byte-swapped clients by default 2023-01-06 11:59:37 +10:00
mi mi: reset the PointerWindows reference on screen switch 2023-10-25 00:37:47 +00:00
miext rootless: Use screen_x and screen_y instead of pixmap pointer hacks 2023-01-20 17:10:54 +00:00
os Switch to libbsd-overlay 2023-08-16 19:56:50 +00:00
present present: add support for PresentOptionAsyncMayTear 2023-06-19 12:19:31 +02:00
pseudoramiX Remove autotools support 2021-10-27 13:15:40 +03:00
randr Xi/randr: fix handling of PropModeAppend/Prepend 2023-10-25 00:32:52 +00:00
record record: Fix out of bounds access in SwapCreateRegister() 2021-12-14 15:00:00 +02:00
render glamor: fix CbCr format handling 2022-12-01 08:41:57 +00:00
test glamor: mark tests fixed by this PR 2023-10-20 14:10:21 +03:00
xfixes Remove "All rights reserved" from Oracle copyright notices 2023-02-25 09:40:41 -08:00
xkb ddxLoad: Check XDG_RUNTIME_DIR before fallback to /tmp/ 2023-04-06 00:48:12 +00:00
.appveyor.yml appveyor: Add libxcvt build dep 2021-11-04 13:03:25 +00:00
.dir-locals.el .dir-locals.el: Add missing final newline 2019-10-01 17:05:28 +00:00
.gitignore .gitignore: Add new autotools file 'test-driver' 2014-04-21 13:41:42 -07:00
.gitlab-ci.yml xwayland: Add XTEST support using EIS 2023-06-26 13:19:19 +02:00
.mailmap Add a .mailmap file to canonicalize author names and emails 2023-03-15 18:10:51 +00:00
.travis.yml travis: Add OSX meson build to matrix 2019-05-02 15:42:58 +00:00
COPYING modesetting: Merge modesetting's COPYING into the xserver's. 2014-09-15 12:46:02 -07:00
README.md Fix spelling/wording issues 2020-07-05 13:07:33 -07:00
meson.build Switch to libbsd-overlay 2023-08-16 19:56:50 +00:00
meson_options.txt xwayland: Add XTEST support using EIS 2023-06-26 13:19:19 +02:00
xorg-server.m4 xorg-server.m4: just all cflags instead of just sdkdir 2018-09-20 20:12:24 +01:00
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: https://en.wikipedia.org/wiki/X_server

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

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

The primary development code repository can be found at:

https://gitlab.freedesktop.org/xorg/xserver

For patch submission instructions, see:

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

As with other projects hosted on freedesktop.org, X.Org follows its Code of Conduct, based on the Contributor Covenant. Please conduct yourself in a respectful and civilized manner when using the above mailing lists, bug trackers, etc:

https://www.freedesktop.org/wiki/CodeOfConduct