[tor-bugs] #30920 [Core Tor/Tor]: Detect uint64 overflow in config_parse_units()

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#30920: Detect uint64 overflow in config_parse_units()
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 Reporter:  nickm          |          Owner:  (none)
     Type:  defect         |         Status:  new
 Priority:  Low            |      Milestone:  Tor: 0.4.2.x-final
Component:  Core Tor/Tor   |        Version:
 Severity:  Minor          |     Resolution:
 Keywords:  easy overflow  |  Actual Points:
Parent ID:                 |         Points:
 Reviewer:                 |        Sponsor:
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Comment (by teor):

 It would be great to have a generic 64-bit multiplication overflow
 function in:
 https://gitweb.torproject.org/tor.git/tree/src/lib/intmath/muldiv.c

 It should look like the overflow checking function in:
 https://gitweb.torproject.org/tor.git/tree/src/lib/intmath/addsub.c

 But with a note that division is expensive on some platforms.
 (Which doesn't matter for a once-off config parse.)

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/30920#comment:2>
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