pull up r21920, r21922, r21926 from trunk

pull up r21920, r21922, r21926 from trunk

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 r21926 | raeburn | 2009-02-09 15:39:54 -0500 (Mon, 09 Feb 2009) | 7 lines
 Changed paths:
    M /trunk/src/lib/krb5/krb/kfree.c

 ticket: 6377

 Fix one more case of an explicit null check before calling a free
 function that does the null check.

 Also, use krb5_free_keyblock_contents instead of open-coding all the
 work (and not trying hard enough to clear the memory).
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 r21922 | raeburn | 2009-02-09 13:13:08 -0500 (Mon, 09 Feb 2009) | 3 lines
 Changed paths:
    M /trunk/src/lib/krb5/os/free_krbhs.c

 ticket: 6377

 Provide omitted return value in last change.
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 r21920 | raeburn | 2009-02-09 12:53:21 -0500 (Mon, 09 Feb 2009) | 8 lines
 Changed paths:
    M /trunk/src/lib/krb5/krb/free_rtree.c
    M /trunk/src/lib/krb5/krb/init_ctx.c
    M /trunk/src/lib/krb5/krb/kfree.c
    M /trunk/src/lib/krb5/krb/preauth2.c
    M /trunk/src/lib/krb5/os/free_krbhs.c
    M /trunk/src/lib/krb5/os/promptusr.c

 ticket: 6377
 subject: make krb5_free_* functions ignore NULL

 This makes them safer to call in various contexts where NULL may leak
 through, and makes analysis easier.

 Also, remove some checks for NULL before calling a free routine that
 will also check for NULL.
 ------------------------------------------------------------------------

ticket: 6377
version_fixed: 1.7
status: resolved

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-7@22032 dc483132-0cff-0310-8789-dd5450dbe970