[tor-bugs] #17443 [Tor]: tor-gencert --passphrase-fd improperly checks for newline

[Tor Bug Tracker & Wiki]

#17443: tor-gencert --passphrase-fd improperly checks for newline
----------------------------+-----------------------------
     Reporter:  junglefowl  |      Owner:
         Type:  defect      |     Status:  new
     Priority:  Medium      |  Milestone:
    Component:  Tor         |    Version:  Tor: 0.2.7.4-rc
     Severity:  Normal      |   Keywords:
Actual Points:              |  Parent ID:
       Points:              |    Sponsor:
----------------------------+-----------------------------
 How to trigger:

 {{{
 $ tor-gencert --create-identity-key --passphrase-fd 0 < /dev/null
 }}}

 It depends on your system what will happen now: assert, not enough memory,
 or nothing.

 This patch properly checks if memchr call returns NULL:

 {{{
  src/tools/tor-gencert.c |    4 ++++
  1 file changed, 4 insertions(+)

 diff --git a/src/tools/tor-gencert.c b/src/tools/tor-gencert.c
 index e833aa9..d4c8c0d 100644
 --- a/src/tools/tor-gencert.c
 +++ b/src/tools/tor-gencert.c
 @@ -103,6 +103,10 @@ load_passphrase(void)
      return -1;
    }
    cp = memchr(buf, '\n', n);
 +  if (cp == NULL) {
 +    log_err(LD_GENERAL, "Couldn't read from passphrase fd: missing
 newline");
 +    return -1;
 +  }
    passphrase_len = cp-buf;
    passphrase = tor_strndup(buf, passphrase_len);
    memwipe(buf, 0, sizeof(buf));
 }}}

 ----

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/17443>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
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