[tor-bugs] #7419 [Tor]: Choose a faster memwipe implementation

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#7419: Choose a faster memwipe implementation
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     Reporter:  nickm        |      Owner:
         Type:  enhancement  |     Status:  needs_review
     Priority:  normal       |  Milestone:  Tor: 0.2.6.x-final
    Component:  Tor          |    Version:
   Resolution:               |   Keywords:  tor-relay, nickm-patch
Actual Points:               |  Parent ID:
       Points:               |
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Comment (by nickm):

 To be clear, I don't think any of my patch requires undefined behavior; do
 you?  In most cases, it accesses non-volatile objects through a volatile
 pointer; not the other way around.  Does the standard forbid that too?  Or
 have I misunderstood?

 Also fwiw, the "external memset wrapper" solution isn't going to work with
 any  compiler that does whole-program optimization.

 The check-after-memset thing you propose might work too .. but I think
 that a compiler is also technically allowed to optimize that whole thing
 out, along with the memset, if it can prove that nothing else will look at
 the buffer afterwards.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7419#comment:11>
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