[GHC] #10826: [Security] Safe Haskell can be bypassed via annotations

[GHC]

#10826: [Security] Safe Haskell can be bypassed via annotations
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        Reporter:  spinda            |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  highest           |               Milestone:  7.10.3
       Component:  Compiler          |                 Version:  7.10.2
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  GHC accepts       |  Unknown/Multiple
  invalid program                    |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by goldfire):

 Sounds to me like we should just disable annotations entirely in Safe
 Haskell. I'm sure someone can be clever enough to sort out the monads, but
 no one is requesting this feature, to my knowledge. And it would be
 peculiar (but certainly conceivable) to use Safe Haskell and then inspect
 .hi files manually (or through `--show-iface`).

 So, unless there are objections: disable annotations in Safe Haskell.

 Do please add a note in the release notes about this. Given that it's a
 safety issue, I think it's reasonable to mark this "merge" so that the fix
 goes into 7.10.3. But others may differ here, as the change could kill
 existing non-malicious code.

 Also, in the error message that happens when a user tries an annotation in
 Safe Haskell, I think it would be best to include a link to this ticket,
 so that users who ''do'' want the feature have a nice place to make
 themselves known.

 Many thanks!

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10826#comment:9>
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