From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Roberts, William C" <william.c.roberts@intel.com>
To: Stephen Smalley <sds@tycho.nsa.gov>, "selinux@tycho.nsa.gov"
 <selinux@tycho.nsa.gov>, "seandroid-list@tycho.nsa.gov"
 <seandroid-list@tycho.nsa.gov>, "jwcart2@tycho.nsa.gov"
 <jwcart2@tycho.nsa.gov>
Subject: RE: [PATCH v2] libselinux: clean up process file
Date: Thu, 8 Sep 2016 19:30:28 +0000
Message-ID: <476DC76E7D1DF2438D32BFADF679FC560128FA5C@ORSMSX103.amr.corp.intel.com>
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<snip>

> > > +	/* Append any given suffix */
> > > +	char *to = stpcpy(&current[current_size], ".");
> >
> > Simpler as:
> > 	char *to = current + current_size;
> > 	*to++ = '.';
> 
> I don't think this is simpler, but I'll do it.

Doing that as is gets us this:
==26050== Conditional jump or move depends on uninitialised value(s)
==26050==    at 0x4C2DD9A: strcat (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==26050==    by 0x4E4B6D8: rolling_append (label_file.c:429)
==26050==    by 0x4E4B8A3: open_file (label_file.c:472)
==26050==    by 0x4E4BAC6: process_file (label_file.c:519)
==26050==    by 0x4E4BE6D: init (label_file.c:582)
==26050==    by 0x4E4D02B: selabel_file_init (label_file.c:965)
==26050==    by 0x4E481F5: selabel_open (label.c:340)
==26050==    by 0x4E513E0: matchpathcon_init_prefix (matchpathcon.c:322)
==26050==    by 0x4E51725: matchpathcon (matchpathcon.c:413)
==26050==    by 0x400D86: printmatchpathcon (matchpathcon.c:26)
==26050==    by 0x40141F: main (matchpathcon.c:196)

Because strcat() needs to fastforward to the null byte, this would need to
change to an strcpy.

<snip>