[tor-bugs] #24826 [Core Tor/Tor]: LZMA- and Zstandard compressed consensus diffs stall Tor Browser launch for at least 20s or break it entirely if compiled with --enable-expensive-hardening

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#24826: LZMA- and Zstandard compressed consensus diffs stall Tor Browser launch for
at least 20s or break it entirely if compiled with --enable-expensive-
hardening
--------------------------+------------------------------------
 Reporter:  gk            |          Owner:  (none)
     Type:  defect        |         Status:  new
 Priority:  Medium        |      Milestone:  Tor: 0.3.3.x-final
Component:  Core Tor/Tor  |        Version:
 Severity:  Normal        |     Resolution:
 Keywords:                |  Actual Points:
Parent ID:  #22341        |         Points:
 Reviewer:                |        Sponsor:
--------------------------+------------------------------------

Comment (by nickm):

 okay, I see:
 {{{
 Jan 16 10:28:52.000 [notice] About to apply consensus diff.
 Jan 16 10:28:52.000 [notice] Computed digest-as-signed for applying
 consensus diff.
 Jan 16 10:29:04.000 [notice] Split consensus into lines.
 Jan 16 10:29:04.000 [notice] Split diff into lines.
 Jan 16 10:29:04.000 [notice] Extracted digests for consensus diff.
 Jan 16 10:29:04.000 [notice] Digests match; applying diff.
 }}}

 So it seems that consdiff_split_lines is the culprit here.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/24826#comment:22>
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