Merged revisions 231911 via svnmerge from

Merged revisions 231911 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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  r231911 | jpeeler | 2009-12-01 15:29:31 -0600 (Tue, 01 Dec 2009) | 12 lines

  Fix crash with invalid frame data

  The crash was happening as a result of a frame containing an invalid data
  pointer, but was set with data length of zero. The few times the issue was
  reproduced it _seemed_ that the frame was queued properly, that is the data
  pointer was set to NULL. I never could reproduce the crash so as a last resort
  the crash has been fixed, but a check in __ast_read has been added to give as
  much information about the source of problematic frames in the future.

  (closes issue #16058)
  Reported by: atis
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@231927 65c4cc65-6c06-0410-ace0-fbb531ad65f3