bin/139492: pkg_install - overlapping data buffer in call to snprintf

[Bruce Cran]

>Number:         139492
>Category:       bin
>Synopsis:       pkg_install - overlapping data buffer in call to snprintf
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Oct 10 19:20:01 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Bruce Cran
>Release:        8.0-RC1
>Organization:
>Environment:
FreeBSD bsd01.localdomain 8.0-RC1 FreeBSD 8.0-RC1 #0: Thu Sep 17 20:45:19 UTC 2009 root at almedia.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC i386
>Description:
On line 270 of usr.sbin/pkg_install/lib/match.c there's a call to snprintf which uses an overlapping buffer:

snprintf(tmp, PATH_MAX, "%s/%s", tmp, CONTENTS_FNAME);

According to http://www.opengroup.org/onlinepubs/000095399/functions/printf.html the results are undefined in the buffers overlap.
>How-To-Repeat:
Install devel/cppcheck and run it in usr.sbin/pkg_install
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: