[tor-bugs] #17475 [Torsocks]: Overflow when parsing config lines with many arguments

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#17475: Overflow when parsing config lines with many arguments
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     Reporter:  junglefowl  |      Owner:  dgoulet
         Type:  defect      |     Status:  new
     Priority:  Medium      |  Milestone:
    Component:  Torsocks    |    Version:
     Severity:  Normal      |   Keywords:
Actual Points:              |  Parent ID:
       Points:              |    Sponsor:
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 It is possible to overflow tokens with a configuration that contains many
 arguments in one line.

 At first, the upper limit is specified as sizeof(tokens), which is
 wrong. It has to be DEFAULT_MAX_CONF_TOKEN or sizeof(tokens) /
 sizeof(tokens[0]). The former is shorter, therefor I took that one.

 The next issue is in utils_tokenize_ignore_comments, which verifies that
 enough space is available only with the ' ' separator. Later in the code,
 '\t' is also allowed as a separator, which means that more arguments could
 show up than previously taken into account during size checks.

 This is an unlikely case, so the check will be done while parsing. When
 the limit is reached, previously allocated memory is released again and
 error value is returned.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/17475>
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