Merged revisions 338801 via svnmerge from

Merged revisions 338801 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/10

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  r338801 | rmudgett | 2011-09-30 17:06:48 -0500 (Fri, 30 Sep 2011) | 19 lines

  Merged revisions 338800 via svnmerge from
  https://origsvn.digium.com/svn/asterisk/branches/1.8

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    r338800 | rmudgett | 2011-09-30 17:05:10 -0500 (Fri, 30 Sep 2011) | 12 lines

    Fix segfault in analog_ss_thread() not checking ast_read() for NULL.

    NOTE: The problem was reported against v1.6.2.  It is unlikely to ever
    happen on v1.8 and above since chan_dahdi.c:analog_ss_thread() is unlikely
    to be used.  The version in sig_analog.c has largely replaced it.

    (closes issue ASTERISK-18648)
    Reported by: Stephan Bosch
    Patches:
          jira_asterisk_18648_v1.8.patch (license #5621) patch uploaded by rmudgett
    Tested by: Stephan Bosch
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@338802 65c4cc65-6c06-0410-ace0-fbb531ad65f3