Bug 4484 - Removing a certificate from a store while in a foreach loop of that store's Certificates property results in an InvalidOperationException
Summary: Removing a certificate from a store while in a foreach loop of that store's C...
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: System.Security ()
Version: master
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2012-04-17 16:39 UTC by David Ferguson
Modified: 2012-04-17 17:10 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description David Ferguson 2012-04-17 16:39:16 UTC
While porting unit tests from Windows (which pass) for the application I'm porting, I came across this one:

        public void RemoveAllProductCertificates()
            var store = GetProductCertificateStore();


                foreach (var certificate in store.Certificates)

This is mainly used in our unit testing teardown/setup, etc.  When store.Remove is called, the exception is thrown.  Here's the callstack:

TearDown : System.InvalidOperationException : List has changed.

 at System.Collections.ArrayList+SimpleEnumerator.MoveNext () [0x00066]
 at System.Security.Cryptography.X509Certificates.X509Certificate2Enumerator.MoveNext () [0x00000]
 at MyNamespace.RemoveAllProductCertificates () [0x00061]

The Certificates property simply returns a list which can't be modified in a foreach.  The Windows api simply wraps other api's so there isn't an internal collection being modified when calling .Remove in the foreach.

Steps to reproduce:

1) Run the above code in a test (backup your store first!)

Expected results:

The code should behave as it does in Windows

Actual results:

A System.InvalidOperationException is thrown

System details:

Mono JIT compiler version 2.11.1 (master/ec75771 Wed Apr 11 14:13:09 EDT 2012)
Copyright (C) 2002-2012 Novell, Inc, Xamarin Inc and Contributors. www.mono-project.com
        TLS:           __thread
        SIGSEGV:       altstack
        Notifications: epoll
        Architecture:  amd64
        Disabled:      none
        Misc:          softdebug 
        LLVM:          supported, not enabled.
        GC:            Included Boehm (with typed GC and Parallel Mark)
Comment 1 David Ferguson 2012-04-17 17:10:19 UTC
store.RemoveRange(store.Certificates) will also throw the exception.

The code below works fine.


                var certs = new X509Certificate2Collection(store.Certificates);