Re: [PATCH] gitk: use mktemp -d to avoid predictable temporary directories

Am 15.06.2014 09:51, schrieb Pat Thoyts:

David Aguilar [off-list ref] writes:

quoted

gitk uses a predictable ".gitk-tmp.$PID" pattern when generating
a temporary directory.

Use "mktemp -d .gitk-tmp.XXXXXX" to harden gitk against someone
seeding /tmp with files matching the pid pattern.

Signed-off-by: David Aguilar <redacted>
---
This issue was brought up during the first review of the previous patch
back in 2009.

http://thread.gmane.org/gmane.comp.version-control.git/132609/focus=132748

This is really [PATCH 2/2] and should be applied on top of my previous
gitk patch.

gitk | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gitk b/gitk
index 82293dd..dd2ff63 100755
--- a/gitk
+++ b/gitk

@@ -3502,7 +3502,8 @@ proc gitknewtmpdir {} {

	} else {
	    set tmpdir $gitdir
	}
-	set gitktmpdir [file join $tmpdir [format ".gitk-tmp.%s" [pid]]]
+	set gitktmpformat [file join $tmpdir ".gitk-tmp.XXXXXX"]
+	set gitktmpdir [exec mktemp -d $gitktmpformat]
	if {[catch {file mkdir $gitktmpdir} err]} {
	    error_popup "[mc "Error creating temporary directory %s:" $gitktmpdir] $err"
	    unset gitktmpdir

This is a problem on Windows where we will not have mktemp. In Tcl 8.6
the file command acquired a "file tempfile" command to help with this
kind of issue (https://www.tcl.tk/man/tcl8.6/TclCmd/file.htm#M39) but
for older versions we should probably stick with the existing pattern at
least on Windows.

We could of course add mktemp from http://www.mktemp.org to msysgit.
I can do that if required.

In mingwgitDevEnv we already have the the need for mktemp, and a msys
package, so this is also not a problem.