Commit Graph

6 Commits

Author SHA1 Message Date
Olivier Fourdan
b768b7d6ce present/wnmd: Fix use after free on CRTC removal
Xwayland will add and remove CRTCs as Wayland outputs are added or
removed.

If there is a pending flip when this occurs, the
`xwl_present_sync_callback()` will be triggered after the Xwayland
output's RRCtrcPtr has been destroyed, hence causing a crash in Xwayland
while trying to use freed memory:

  #1  abort ()
  #2  OsAbort () at utils.c:1350
  #3  AbortServer () at log.c:877
  #4  FatalError () at log.c:1015
  #5  OsSigHandler () at osinit.c:156
  #6  <signal handler called>
  #7  dixGetPrivate () at ../include/privates.h:122
  #8  dixLookupPrivate () at ../include/privates.h:166
  #9  present_screen_priv () at present_priv.h:198
  #10 present_wnmd_flip () at present_wnmd.c:358
  #11 present_wnmd_execute () at present_wnmd.c:466
  #12 present_wnmd_re_execute () at present_wnmd.c:80
  #13 xwl_present_sync_callback () at xwayland-present.c:287
  #14 ffi_call_unix64 () from /lib64/libffi.so.6
  #15 ffi_call () from /lib64/libffi.so.6
  #16 wl_closure_invoke () at src/connection.c:1006
  #17 dispatch_event () at src/wayland-client.c:1427
  #18 dispatch_queue () at src/wayland-client.c:1573
  #19 wl_display_dispatch_queue_pending () at src/wayland-client.c:1815
  #20 wl_display_dispatch_pending () at src/wayland-client.c:1878
  #21 xwl_read_events () at xwayland.c:814
  #22 ospoll_wait () at ospoll.c:651
  #23 WaitForSomething () at WaitFor.c:208
  #24 Dispatch () at ../include/list.h:220
  #25 dix_main () at main.c:276

To avoid the issue, get the `ScreenPtr` from the window instead of the
CRTC that might have been just freed, `xwl_present_flip()` has no use
for the CRTC anyway.

Bugzilla: https://bugs.freedesktop.org/108249
Suggested-by: Michel Daenzer <michel.daenzer@amd.com>
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Michel Daenzer <michel.daenzer@amd.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
2018-10-25 15:05:12 +00:00
Lionel Landwerlin
ce271535ad present: fix freed pointer access
When a vblank has been marked as aborted, it's going to be free in the
flip_notify function when stopped. We can't notify it after it's
stopped because the pointer is invalid.

Valgrind backtrace:

==5331== Invalid read of size 8
==5331==    at 0x212B4D: present_vblank_notify (present_vblank.c:34)
==5331==    by 0x21439B: present_wnmd_flip_notify (present_wnmd.c:194)
==5331==    by 0x21439B: present_wnmd_event_notify (present_wnmd.c:228)
==5331==    by 0x156216: xwl_present_sync_callback (xwayland-present.c:282)
==5331==    by 0x6570FCD: ffi_call_unix64 (in /usr/lib/x86_64-linux-gnu/libffi.so.6.0.4)
==5331==    by 0x657093E: ffi_call (in /usr/lib/x86_64-linux-gnu/libffi.so.6.0.4)
==5331==    by 0x4DDB183: ??? (in /usr/lib/x86_64-linux-gnu/libwayland-client.so.0.3.0)
==5331==    by 0x4DD79D8: ??? (in /usr/lib/x86_64-linux-gnu/libwayland-client.so.0.3.0)
==5331==    by 0x4DD8EA3: wl_display_dispatch_queue_pending (in /usr/lib/x86_64-linux-gnu/libwayland-client.so.0.3.0)
==5331==    by 0x14BCCA: xwl_read_events (xwayland.c:814)
==5331==    by 0x2AC0D0: ospoll_wait (ospoll.c:651)
==5331==    by 0x2A5322: WaitForSomething (WaitFor.c:208)
==5331==    by 0x27574B: Dispatch (dispatch.c:421)
==5331==  Address 0x1b44dc98 is 40 bytes inside a block of size 184 free'd
==5331==    at 0x48369EB: free (vg_replace_malloc.c:530)
==5331==    by 0x213B0A: present_wnmd_free_idle_vblanks (present_wnmd.c:118)
==5331==    by 0x213B0A: present_wnmd_flips_stop (present_wnmd.c:161)
==5331==    by 0x2143EF: present_wnmd_flip_notify (present_wnmd.c:192)
==5331==    by 0x2143EF: present_wnmd_event_notify (present_wnmd.c:228)
==5331==    by 0x156216: xwl_present_sync_callback (xwayland-present.c:282)
==5331==    by 0x6570FCD: ffi_call_unix64 (in /usr/lib/x86_64-linux-gnu/libffi.so.6.0.4)
==5331==    by 0x657093E: ffi_call (in /usr/lib/x86_64-linux-gnu/libffi.so.6.0.4)
==5331==    by 0x4DDB183: ??? (in /usr/lib/x86_64-linux-gnu/libwayland-client.so.0.3.0)
==5331==    by 0x4DD79D8: ??? (in /usr/lib/x86_64-linux-gnu/libwayland-client.so.0.3.0)
==5331==    by 0x4DD8EA3: wl_display_dispatch_queue_pending (in /usr/lib/x86_64-linux-gnu/libwayland-client.so.0.3.0)
==5331==    by 0x14BCCA: xwl_read_events (xwayland.c:814)
==5331==    by 0x2AC0D0: ospoll_wait (ospoll.c:651)
==5331==    by 0x2A5322: WaitForSomething (WaitFor.c:208)
==5331==  Block was alloc'd at
==5331==    at 0x48377D5: calloc (vg_replace_malloc.c:711)
==5331==    by 0x212D9F: present_vblank_create (present_vblank.c:69)
==5331==    by 0x214014: present_wnmd_pixmap (present_wnmd.c:610)
==5331==    by 0x21576C: proc_present_pixmap (present_request.c:150)
==5331==    by 0x27599D: Dispatch (dispatch.c:479)
==5331==    by 0x279945: dix_main (main.c:276)
==5331==    by 0x633AB16: (below main) (libc-start.c:310)

v2: Still notify aborted flips (Roman)

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107314
Reviewed-by: Roman Gilg <subdiff@gmail.com>
Tested-by: Roman Gilg <subdiff@gmail.com>
2018-09-10 10:03:03 -04:00
Michel Dänzer
10eec2ccb1 present/wnmd: Preserve window pixmap's screen_x/y on flip
The incorrect values could result in the new pixmap's contents
getting corrupted down the line.

v2:
* Guard screen_x/y lines by #ifdef COMPOSITE

Bugzilla: https://bugs.freedesktop.org/106841
Fixes: 029608dd80 "present: Add window flip mode"
Reviewed-by: Adam Jackson <ajax@redhat.com> # v1
Reviewed-by: Keith Packard <keithp@keithp.com> # v1
Reviewed-by: Roman Gilg <subdiff@gmail.com>
Tested-by: Olivier Fourdan <ofourdan@redhat.com> # v1
2018-06-08 11:18:30 +02:00
Roman Gilg
22285a6f1c present: fix msc offset calculation in window mode
Instead of getting the current msc value from the window, which might be
different to old one directly take the last saved msc value saved in
the window_priv struct.

Signed-off-by: Roman Gilg <subdiff@gmail.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
2018-05-02 14:55:48 -04:00
Roman Gilg
66a5c0bccb present: In window flip mode report damage on flip to driver
Calculate damage before trying to flip and report it to the driver.
This allows drivers to optimize their rendering.

Signed-off-by: Roman Gilg <subdiff@gmail.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
2018-03-28 14:36:39 -04:00
Roman Gilg
029608dd80 present: Add window flip mode
In contrast to screen flip mode this mode:
* supports flips per windows (these windows currently need to have the same
  size as their parent windows with the same pixmap),
* sends pixmap idle signals to the client only after the driver has given
  an additional event notify.

This patch only introduces the new mode as a stub. It additionally needs a
driver hook, such that it can get initialized and appropriate cleanup
functions.

Signed-off-by: Roman Gilg <subdiff@gmail.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
2018-03-28 14:36:36 -04:00