dc7cb45482
Fix the following race: Possible data race during read of size 8 at 0xA112510 by thread #6 Locks held: 1, at address 0x366B40 at 0x14C8B9: GetMaster (devices.c:2691) by 0x15CFC5: IsFloating (events.c:346) by 0x2B9554: miPointerGetScreen (mipointer.c:527) by 0x1A5136: xf86PostButtonEventM (xf86Xinput.c:1379) by 0x1A52BD: xf86PostButtonEvent (xf86Xinput.c:1345) by 0x485F45B: EvdevProcessEvent (in /usr/lib64/xorg/modules/input/evdev_drv.so) by 0x485FDAC: EvdevReadInput (in /usr/lib64/xorg/modules/input/evdev_drv.so) by 0x195427: xf86ReadInput (xf86Events.c:247) by 0x2CC113: InputReady (inputthread.c:180) by 0x2CE4EA: ospoll_wait (ospoll.c:657) by 0x2CC077: InputThreadDoWork (inputthread.c:369) by 0x484A336: mythread_wrapper (hg_intercepts.c:406) This conflicts with a previous write of size 8 by thread #1 Locks held: none at 0x14D2C6: AttachDevice (devices.c:2609) by 0x15CF85: ReattachToOldMaster (events.c:1457) by 0x1647DD: DeactivateKeyboardGrab (events.c:1700) by 0x25D7F1: ProcXIUngrabDevice (xigrabdev.c:169) by 0x2552AD: ProcIDispatch (extinit.c:398) by 0x155291: Dispatch (dispatch.c:479) by 0x158CBA: dix_main (main.c:276) by 0x143A3D: main (stubmain.c:34) Address 0xa112510 is 336 bytes inside a block of size 904 alloc'd at 0x4846571: calloc (vg_replace_malloc.c:1328) by 0x14A0B3: AddInputDevice (devices.c:260) by 0x1A31A0: xf86ActivateDevice (xf86Xinput.c:365) by 0x1A4549: xf86NewInputDevice (xf86Xinput.c:948) by 0x1A4B44: NewInputDeviceRequest (xf86Xinput.c:1090) by 0x1B81FE: device_added (udev.c:282) by 0x1B8516: config_udev_init (udev.c:439) by 0x1B7091: config_init (config.c:50) by 0x197970: InitInput (xf86Init.c:814) by 0x158C6B: dix_main (main.c:250) by 0x143A3D: main (stubmain.c:34) Block was alloc'd by thread #1 The steps to trigger the race are: 1. Main thread does cleanup at mipointer.c:360 setting the slave device's miPointerPtr to null. 2. Input thread use MIPOINTER in mipointer.c and get the slave's miPointerPtr = null. 3. Main thread updates dev->master at devices.c:2609. 4. MIPOINTER would now return the master's miPointerPtr but the input thread already got the slave's miPointerPtr in step 2 and segfaults by null ptr deref. Closes: https://gitlab.freedesktop.org/xorg/xserver/-/issues/1260 Signed-off-by: Thomas Lindroth <thomas.lindroth@gmail.com> |
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| meson.build | ||
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| xserver.ent.in | ||
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
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https://lists.freedesktop.org/mailman/listinfo/xorg
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https://gitlab.freedesktop.org/xorg/xserver
For patch submission instructions, see:
https://www.x.org/wiki/Development/Documentation/SubmittingPatches
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