docs/108346: tmpnam(3) should note that that TMPDIR env may be ignored

[Anton Yuzhaninov]

>Number:         108346
>Category:       docs
>Synopsis:       tmpnam(3) should note that that TMPDIR env may be ignored
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-doc
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          doc-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Jan 25 17:40:21 GMT 2007
>Closed-Date:
>Last-Modified:
>Originator:     Anton Yuzhaninov
>Release:        FreeBSD 6.2-RELEASE amd64
>Organization:
Rambler
>Environment:
>Description:
tmpnam(3) should note that that tmpfile() ignore TMPDIR environment variable if
issetugid(3) return non zero.
>How-To-Repeat:
>Fix:

Anything like this:

--- lib/libc/stdio/tmpnam.3.orig        Thu Jan 25 20:02:50 2007
+++ lib/libc/stdio/tmpnam.3     Thu Jan 25 20:19:59 2007
@@ -156,6 +156,16 @@
 .Dv NULL
 pointer
 on error.
+.Sh ENVIRONMENT
+The
+.Fn tmpfile
+ignores the
+.Ev TMPDIR
+environment variable if process created as a result of an
+.Xr execve 2
+system call which had either of the setuid or setgid bits set (and extra
+privileges were given as a result) or if it has changed any of its real,
+effective or saved user or group ID's since it began execution.
 .Sh COMPATIBILITY
 These interfaces are provided from System V and
 .Tn ANSI
@@ -228,7 +238,8 @@
 the FSA.)
 .Sh SEE ALSO
 .Xr mkstemp 3 ,
-.Xr mktemp 3
+.Xr mktemp 3 ,
+.Xr issetugid 2
 .Rs
 .%T "The FreeBSD Security Architecture"
 .Re
>Release-Note:
>Audit-Trail:
>Unformatted: