[PATCH 2/2] Use event time instead of CurrentTime for grab times

Chase Douglas chase.douglas at canonical.com
Wed Jan 11 07:38:12 PST 2012

When {XI,X,}AllowEvents is called, the timestamp is compared against the
grab time to ensure that the request pertains to the current grab in the
server. While many clients may use CurrentTime (client-side), the
timestamp of the event causing the grab is also valid.

This change ensures that the server's notion of the grab time is the
time of the event that activated the grab rather than the time that the
grab is actually activated.

This bug was exposed through nested touch then pointer grabs.

Signed-off-by: Chase Douglas <chase.douglas at canonical.com>
 dix/events.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/dix/events.c b/dix/events.c
index 5360267..d4b00e0 100644
--- a/dix/events.c
+++ b/dix/events.c
@@ -3723,7 +3723,8 @@ ActivatePassiveGrab(DeviceIntPtr device, GrabPtr grab, InternalEvent *event,
-    (*grabinfo->ActivateGrab)(device, grab, currentTime, TRUE);
+    (*grabinfo->ActivateGrab)(device, grab,
+                              ClientTimeToServerTime(event->any.time), TRUE);
     if (xE)

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