From: Paul Eggert <eggert@cs.ucla.edu>
Date: Sat, 14 Jan 2012 07:09:15 +0000 (+0800)
Subject: Fix race condition in epg.el compat code.
X-Git-Tag: emacs-pretest-24.0.93~97^2~17^2~11
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=9e5788aaef98e88aeb5b2476549f72b591e0bf4a;p=emacs.git

Fix race condition in epg.el compat code.

* lisp/epg.el (epg--make-temp-file): Avoid permission race condition
when running on old Emacs versions.

Fixes: debbugs:10403
---

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 98312d64853..968e2f91996 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2012-01-14  Paul Eggert  <eggert@cs.ucla.edu>
+
+	* epg.el (epg--make-temp-file): Avoid permission race condition
+	when running on old Emacs versions (bug#10403).
+
 2012-01-14  Glenn Morris  <rgm@gnu.org>
 
 	* dired.el (dired-get-filename): Fix 'verbatim case of previous change.
diff --git a/lisp/epg.el b/lisp/epg.el
index 3505e183c1f..6529afb2d3c 100644
--- a/lisp/epg.el
+++ b/lisp/epg.el
@@ -1951,7 +1951,8 @@ The returned file name (created by appending some random characters at the end
 of PREFIX, and expanding against `temporary-file-directory' if necessary),
 is guaranteed to point to a newly created empty file.
 You can then use `write-region' to write new data into the file."
-      (let (tempdir tempfile)
+      (let ((orig-modes (default-file-modes))
+	    tempdir tempfile)
 	(setq prefix (expand-file-name prefix
 				       (if (featurep 'xemacs)
 					   (temp-directory)
@@ -1959,6 +1960,7 @@ You can then use `write-region' to write new data into the file."
 	(unwind-protect
 	    (let (file)
 	      ;; First, create a temporary directory.
+	      (set-default-file-modes #o700)
 	      (while (condition-case ()
 			 (progn
 			   (setq tempdir (make-temp-name
@@ -1969,14 +1971,12 @@ You can then use `write-region' to write new data into the file."
 			   (make-directory tempdir))
 		       ;; let's try again.
 		       (file-already-exists t)))
-	      (set-file-modes tempdir 448)
 	      ;; Second, create a temporary file in the tempdir.
 	      ;; There *is* a race condition between `make-temp-name'
 	      ;; and `write-region', but we don't care it since we are
 	      ;; in a private directory now.
 	      (setq tempfile (make-temp-name (concat tempdir "/EMU")))
 	      (write-region "" nil tempfile nil 'silent)
-	      (set-file-modes tempfile 384)
 	      ;; Finally, make a hard-link from the tempfile.
 	      (while (condition-case ()
 			 (progn
@@ -1986,6 +1986,7 @@ You can then use `write-region' to write new data into the file."
 		       ;; let's try again.
 		       (file-already-exists t)))
 	      file)
+	  (set-default-file-modes orig-modes)
 	  ;; Cleanup the tempfile.
 	  (and tempfile
 	       (file-exists-p tempfile)