ByteBufferAsyncProcessor: prevent deadlocks on corrupted state exceptions #189
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ForNeVeR
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…ions It turns out that some of our code works under [HandleProcessCorruptedStateExceptions] attribute on .NET Framework. This attribute allows the process to proceed execution even in case of memory access violation, but will only execute catch and finally blocks in direct methods marked with the attribute. So, if ByteBufferAsyncProcessor.Put is called from such method, and then an exception occurs inside of the lock block, the lock will be abandoned in a locked state. This could lead to deadlocks that are hard to detect. Provided we don't want to change the behavior of all the external code right now, the safest action we could take is to guard the path leading to our logger with the same attribute. It will at least help to preserve the logger functionality even in case of corrupted state exception, which should be helpful.
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ulex
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Dec 19, 2020
sergeyQx
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Dec 21, 2020
| @@ -463,6 +463,9 @@ public bool Terminate(int timeoutMs = Timeout.Infinite) | |||
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| #if !NET35 | |||
| [System.Runtime.ExceptionServices.HandleProcessCorruptedStateExceptions] // to force myLock to be unlocked even in case of corrupted state exception | |||
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I would have also added logging of the exception
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Thanks, a good idea! See #190.
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It turns out that some of our code works under
HandleProcessCorruptedStateExceptionsattribute on .NET Framework. This attribute allows the process to proceed execution even in case of memory access violation, but will only executecatchandfinallyblocks (including the implicitly generatedfinallyin case of alockblock) in methods directly marked with the attribute.So, if
ByteBufferAsyncProcessor.Putis called from such method, and then a corrupted state exception occurs inside of thelockblock, the lock will be abandoned in a locked state. This could lead to deadlocks that are hard to detect.Provided we don't want to change the behavior of all the external code right now, the safest action we could take is to guard the path leading to our logger with the same attribute. It will at least help to preserve the logger functionality even in case of corrupted state exception, which should be helpful.