0a07446318
On pointer enter notification, Xwayland checks for an existing pointer warp with a `NULL` sprite. In turn, `xwl_pointer_warp_emulator_maybe_lock()` checks for an existing grab and the destination window using `XYToWindow()` which does not check for the actual sprite not being `NULL`. So, in some cases, when the pointer enters the surface and there is an existing X11 grab which is not an ownerEvents grab, Xwayland would crash trying to dereference the `NULL` sprite pointer: #0 __GI_raise () #1 __GI_abort () at abort.c:79 #2 OsAbort () at utils.c:1351 #3 AbortServer () at log.c:879 #4 FatalError () at log.c:1017 #5 OsSigHandler () at osinit.c:156 #6 OsSigHandler () at osinit.c:110 #7 <signal handler called> #8 XYToWindow (pSprite=0x0, x=0, y=0) at events.c:2880 #9 xwl_pointer_warp_emulator_maybe_lock () at xwayland-input.c:2673 #10 pointer_handle_enter () at xwayland-input.c:434 Avoid the crash by simply checking for the sprite being not `NULL` in `xwl_pointer_warp_emulator_maybe_lock()` Signed-off-by: Olivier Fourdan <ofourdan@redhat.com> Bugzilla: https://bugzilla.redhat.com/1708119
X Server
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