From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Sat, 20 Oct 2018 02:31:35 +0000 (-0400)
Subject: * lisp/mail/smtpmail.el: (smtpmail-send-queued-mail): Avoid 'load'
X-Git-Tag: emacs-27.0.90~4271
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=d684f5d5bc33249038e779a4b2009fd0761f09d5;p=emacs.git

* lisp/mail/smtpmail.el: (smtpmail-send-queued-mail): Avoid 'load'

(smtpmail-send-it): Send metadata directly to the
files without bothering to write it into a temp buffer.
---

diff --git a/lisp/mail/smtpmail.el b/lisp/mail/smtpmail.el
index 8bc3cc78d95..9b045b25584 100644
--- a/lisp/mail/smtpmail.el
+++ b/lisp/mail/smtpmail.el
@@ -150,7 +150,8 @@ and sent with `smtpmail-send-queued-mail'."
   :group 'smtpmail)
 
 (defcustom smtpmail-queue-dir "~/Mail/queued-mail/"
-  "Directory where `smtpmail.el' stores queued mail."
+  "Directory where `smtpmail.el' stores queued mail.
+This directory should not be writable by other users."
   :type 'directory
   :group 'smtpmail)
 
@@ -360,9 +361,7 @@ for `smtpmail-try-auth-method'.")
 		     smtpmail-queue-dir))
 		   (file-data (convert-standard-filename file-data))
 		   (file-elisp (concat file-data ".el"))
-		   (buffer-data (create-file-buffer file-data))
-		   (buffer-elisp (create-file-buffer file-elisp))
-		   (buffer-scratch "*queue-mail*"))
+		   (buffer-data (create-file-buffer file-data)))
 	      (unless (file-exists-p smtpmail-queue-dir)
 		(make-directory smtpmail-queue-dir t))
 	      (with-current-buffer buffer-data
@@ -377,22 +376,16 @@ for `smtpmail-try-auth-method'.")
 		 nil t)
 		(insert-buffer-substring tembuf)
 		(write-file file-data)
-		(set-buffer buffer-elisp)
-		(erase-buffer)
-		(insert (concat
-			 "(setq smtpmail-recipient-address-list '"
+                (write-region
+                 (concat "(setq smtpmail-recipient-address-list '"
 			 (prin1-to-string smtpmail-recipient-address-list)
-			 ")\n"))
-		(write-file file-elisp)
-		(set-buffer (generate-new-buffer buffer-scratch))
-		(insert (concat file-data "\n"))
-		(append-to-file (point-min)
-				(point-max)
-                                (expand-file-name smtpmail-queue-index-file
-                                                  smtpmail-queue-dir)))
-	      (kill-buffer buffer-scratch)
-	      (kill-buffer buffer-data)
-	      (kill-buffer buffer-elisp))))
+			 ")\n")
+                 nil file-elisp nil 'silent)
+		(write-region (concat file-data "\n") nil
+                              (expand-file-name smtpmail-queue-index-file
+                                                smtpmail-queue-dir)
+                              t 'silent))
+	      (kill-buffer buffer-data))))
       (kill-buffer tembuf)
       (if (bufferp errbuf)
 	  (kill-buffer errbuf)))))
@@ -412,7 +405,21 @@ for `smtpmail-try-auth-method'.")
       (goto-char (point-min))
       (while (not (eobp))
 	(setq file-msg (buffer-substring (point) (line-end-position)))
-	(load file-msg)
+        ;; FIXME: Avoid `load' which can execute arbitrary code and is hence
+        ;; a source of security holes.  Better read the file and extract the
+        ;; data "by hand".
+	;;(load file-msg)
+        (with-temp-buffer
+          (insert-file-contents (concat file-msg ".el"))
+          (goto-char (point-min))
+          (pcase (read (current-buffer))
+            (`(setq smtpmail-recipient-address-list ',v)
+             (skip-chars-forward " \n\t")
+             (unless (eobp) (message "Ignoring trailing text in %S"
+                                     (concat file-msg ".el")))
+             (setq smtpmail-recipient-address-list v))
+            (sexp (error "Unexpected code in %S: %S"
+                         (concat file-msg ".el") sexp))))
 	;; Insert the message literally: it is already encoded as per
 	;; the MIME headers, and code conversions might guess the
 	;; encoding wrongly.