[tor-bugs] #20894 [Core Tor/Tor]: Resolve read-off-end-of-buffer on atoi in fetch_from_buf_http (TROVE-2016-10-001)

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#20894: Resolve read-off-end-of-buffer on atoi in fetch_from_buf_http
(TROVE-2016-10-001)
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 Reporter:  teor                       |          Owner:  nickm
     Type:  defect                     |         Status:  needs_review
 Priority:  High                       |      Milestone:  Tor:
                                       |  0.3.0.x-final
Component:  Core Tor/Tor               |        Version:  Tor: unspecified
 Severity:  Normal                     |     Resolution:
 Keywords:  tor-03-unspecified-201612  |  Actual Points:
Parent ID:                             |         Points:  0.5
 Reviewer:                             |        Sponsor:
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Changes (by nickm):

 * status:  needs_revision => needs_review


Comment:

 > Can headers+headerlen can wrap here?

 I believe it can't, since headers is a pointer to a place in a buffer, and
 headerlen is an amount of memory that's readable at that point.

 I've forward-ported to 0.2.9, moved the unit test, added a correct use of
 STATIC, and credited AFL in a branch `bug20894_029_v3`.  I'm fine taking
 this in 0.3.0 or 0.2.9.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/20894#comment:10>
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