Re: [PATCH] Use an unique temporary multistrap file and remove it afterwards
Johannes Schauer <[email protected]>
| Newsgroups | gmane.linux.debian.devel.embedded |
|---|---|
| Message-ID | <20110625180450.GB10039@hoothoot> |
Hi, On Sat, Jun 25, 2011 at 06:20:17PM +0200, Yann Dirson wrote: > > With adding the Process ID to the temporary multistrap configuration file > > makes it unique. This allows multiple invocations on the same time. > > For multi user system as Linux is, is this important. > While it is better than the original, it still allows for attacks - > using a predictable filename in /tmp is always a security issue, and > even the PID does make it imune to attacks (google for "tmp symlink > attack" for details). symlink attacks are hardly an issue because in contrast to other bootstrapping tools polystrap is designed to work without superuser permissions. > Please consider using tempfile(1) for safely getting a temporary file. That was already done after I was made aware of the issue. Since files in /tmp are generally a security issue, the tempfile is now created in the current working directory. Hope this now makes everybody happy :) I was also thinking of using something like process substitution from bash to circumvent the use of any temporary file (or fifo) but the <(cmd) syntax is sadly bash-only. cheers, josch