From c0989dce2d882c94eb3183e7b94402ba53534abb Mon Sep 17 00:00:00 2001
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From: David Adam <zanchey@ucc.gu.uwa.edu.au>
Date: Sun, 20 Apr 2014 23:51:20 +0800
Subject: [PATCH 4/4] use mktemp(1) to generate temporary file names
Fix for CVE-2014-2906.
Closes a race condition in funced which would allow execution of
arbitrary code; closes a race condition in psub which would allow
alternation of the data stream.
Note that `psub -f` does not work (#1040); a fix should be committed
separately for ease of maintenance.
---
share/functions/funced.fish | 6 +-----
share/functions/psub.fish | 11 +++--------
2 files changed, 4 insertions(+), 13 deletions(-)
diff --git a/share/functions/funced.fish b/share/functions/funced.fish
index 3c2de06..ca2e277 100644
--- a/share/functions/funced.fish
+++ b/share/functions/funced.fish
@@ -81,11 +81,7 @@ function funced --description 'Edit function definition'
return 0
end
- set -q TMPDIR; or set -l TMPDIR /tmp
- set -l tmpname (printf "$TMPDIR/fish_funced_%d_%d.fish" %self (random))
- while test -f $tmpname
- set tmpname (printf "$TMPDIR/fish_funced_%d_%d.fish" %self (random))
- end
+ set tmpname (mktemp -t fish_funced.XXXXXXXXXX)
if functions -q -- $funcname
functions -- $funcname > $tmpname
diff --git a/share/functions/psub.fish b/share/functions/psub.fish
index 42e34c7..7877aa4 100644
--- a/share/functions/psub.fish
+++ b/share/functions/psub.fish
@@ -45,21 +45,16 @@ function psub --description "Read from stdin into a file and output the filename
return
end
- # Find unique file name for writing output to
- while true
- set filename /tmp/.psub.(echo %self).(random);
- if not test -e $filename
- break;
- end
- end
-
if test use_fifo = 1
# Write output to pipe. This needs to be done in the background so
# that the command substitution exits without needing to wait for
# all the commands to exit
+ set dir (mktemp -d /tmp/.psub.XXXXXXXXXX); or return
+ set filename $dir/psub.fifo
mkfifo $filename
cat >$filename &
else
+ set filename (mktemp /tmp/.psub.XXXXXXXXXX)
cat >$filename
end
--
1.9.0