[tor-bugs] #23233 [Core Tor/Tor]: Unexpected BUG violation in hsv3 decriptor decoding

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#23233: Unexpected BUG violation in hsv3 decriptor decoding
------------------------------+--------------------------
     Reporter:  haxxpop       |      Owner:  (none)
         Type:  defect        |     Status:  new
     Priority:  Medium        |  Milestone:
    Component:  Core Tor/Tor  |    Version:
     Severity:  Normal        |   Keywords:  prop224,easy
Actual Points:                |  Parent ID:
       Points:                |   Reviewer:
      Sponsor:                |
------------------------------+--------------------------
 As you can see in hs_descriptor.c

 {{{
   /* Find the start of signature. */
   sig_start = tor_memstr(encoded_desc, encoded_len, "\n" str_signature);
   /* Getting here means the token parsing worked for the signature so if
 we
    * can't find the start of the signature, we have a code flow issue. */
   if (BUG(!sig_start)) {
     goto err;
   }
 }}}

 str_signature is "signature", so, if you send the "\n signature" (like in
 the attachment) instead of "\nsignature" tor_memstr will return null and
 violate `BUG(!sig_start)`

 I suggest that we should just remove BUG and let it be `if (!sig_start) {`

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23233>
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