[NO TESTS NEEDED] Do not return from c.stop() before re-locking #9624
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@vrothberg PTAL |
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[APPROVALNOTIFIER] This PR is APPROVED This pull-request has been approved by: mheon The full list of commands accepted by this bot can be found here. The pull request process is described here
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Mar 5, 2021
| if err := c.ociRuntime.StopContainer(c, timeout, all); err != nil { | ||
| return err | ||
| } | ||
| stopErr := c.ociRuntime.StopContainer(c, timeout, all) |
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Could you drop a comment here explaining why we must move the error check below the potential Lock(). It's easy to miss and since we can't test, we may silently regress.
Unlocking an already unlocked lock is a panic. As such, we have to make sure that the deferred c.lock.Unlock() in c.StopWithTimeout() always runs on a locked container. There was a case in c.stop() where we could return an error after we unlock the container to stop it, but before we re-lock it - thus allowing for a double-unlock to occur. Fix the error return to not happen until after the lock has been re-acquired. Fixes containers#9615 Signed-off-by: Matthew Heon <[email protected]>
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/lgtm |
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locked - please file new issue/PR
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Unlocking an already unlocked lock is a panic. As such, we have to make sure that the deferred c.lock.Unlock() in c.StopWithTimeout() always runs on a locked container. There was a case in c.stop() where we could return an error after we unlock the container to stop it, but before we re-lock it - thus allowing for a double-unlock to occur. Fix the error return to not happen until after the lock has been re-acquired.
Fixes #9615
No tests needed because I have no idea how to test this one - the most obvious way would be to put the container in an invalid state, but there's no way to do that without racing against the cleanup process.