clipmenud: Prevent race in disable/enable by checking X timestamps #254
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| /** | ||
| * Get the current X server time by triggering a PropertyNotify. | ||
| */ | ||
| static Time get_current_server_time(void) { |
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@N-R-K do you know a better way to do this? i wondered if there was some extension that can help here, but it seems not?
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i wondered if there was some extension that can help here, but it seems not?
@cdown Well, yes, I do happen to have a bit of esoteric knowledge in this matter. Roughly, you'd need to do the following:
XSyncQueryExtension()+XSyncInitialize()at startup for initialization.- Then use
XSyncListSystemCounters()to get a list of available counters. - Iterate over them to find "SERVERTIME".
- Now you should be able to use
XSyncQueryCounter()to query the server time with the counter id found via step 3.
But I'm not entirely sure if this is worth the trouble. Can't client set arbitrary timestamps anyways? Though I guess from a security perspective it makes sense to completely eliminate any chances of storing a sensitive clip that should've been discarded.
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Thank you! I guessed you might have some knowledge here :-)
Okay, I guess we'll stick with the PropertyNotify method for now since we don't need the XSync guarantees (and it's less code).
cdown
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When clipmenud is rapidly disabled and reenabled, stale X11 selection events queued while disabled could be processed after reenabling, causing entries we should have thrown away to be stored. This is theoretical, there are no user reports of issues. Fixes #217.
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When clipmenud is rapidly disabled and reenabled, stale X11 selection events queued while disabled could be processed after reenabling, causing entries we should have thrown away to be stored.
This is theoretical, there are no user reports of issues.
Fixes #217.