From: Jean Delvare <jdelvare@suse.de>
Date: Thu, 3 May 2018 14:31:55 +0200
Subject: Don't leak temporary file on failed ed-style patch
Git-commit: 19599883ffb6a450d2884f081f8ecf68edbed7ee
Patch-mainline: yes
References: bsc#1092500, savannah#53820

Now that we write ed-style patches to a temporary file before we
apply them, we need to ensure that the temporary file is removed
before we leave, even on fatal error.

* src/pch.c (do_ed_script): Use global TMPEDNAME instead of local
  tmpname. Don't unlink the file directly, instead tag it for removal
  at exit time.
* src/patch.c (cleanup): Unlink TMPEDNAME at exit.

This closes bug #53820:
https://savannah.gnu.org/bugs/index.php?53820

Fixes: 123eaff0d5d1 ("Fix arbitrary command execution in ed-style patches (CVE-2018-1000156)")
---
 src/common.h |    2 ++
 src/patch.c  |    1 +
 src/pch.c    |   11 +++++------
 3 files changed, 8 insertions(+), 6 deletions(-)

--- a/src/common.h
+++ b/src/common.h
@@ -94,10 +94,12 @@ XTERN char const *origsuff;
 XTERN char const * TMPINNAME;
 XTERN char const * TMPOUTNAME;
 XTERN char const * TMPPATNAME;
+XTERN char const * TMPEDNAME;
 
 XTERN bool TMPINNAME_needs_removal;
 XTERN bool TMPOUTNAME_needs_removal;
 XTERN bool TMPPATNAME_needs_removal;
+XTERN bool TMPEDNAME_needs_removal;
 
 #ifdef DEBUGGING
 XTERN int debug;
--- a/src/patch.c
+++ b/src/patch.c
@@ -1999,6 +1999,7 @@ cleanup (void)
   remove_if_needed (TMPINNAME, &TMPINNAME_needs_removal);
   remove_if_needed (TMPOUTNAME, &TMPOUTNAME_needs_removal);
   remove_if_needed (TMPPATNAME, &TMPPATNAME_needs_removal);
+  remove_if_needed (TMPEDNAME, &TMPEDNAME_needs_removal);
   remove_if_needed (TMPREJNAME, &TMPREJNAME_needs_removal);
   output_files (NULL);
 }
--- a/src/pch.c
+++ b/src/pch.c
@@ -2392,7 +2392,6 @@ do_ed_script (char const *inname, char c
     file_offset beginning_of_this_line;
     size_t chars_read;
     FILE *tmpfp = 0;
-    char const *tmpname;
     int tmpfd;
     pid_t pid;
     int exclusive = *outname_needs_removal ? 0 : O_EXCL;
@@ -2406,12 +2405,13 @@ do_ed_script (char const *inname, char c
 	   invalid commands and treats the next line as a new command, which
 	   can lead to arbitrary command execution.  */
 
-	tmpfd = make_tempfile (&tmpname, 'e', NULL, O_RDWR | O_BINARY, 0);
+	tmpfd = make_tempfile (&TMPEDNAME, 'e', NULL, O_RDWR | O_BINARY, 0);
 	if (tmpfd == -1)
-	  pfatal ("Can't create temporary file %s", quotearg (tmpname));
+	  pfatal ("Can't create temporary file %s", quotearg (TMPEDNAME));
+	TMPEDNAME_needs_removal = true;
 	tmpfp = fdopen (tmpfd, "w+b");
 	if (! tmpfp)
-	  pfatal ("Can't open stream for file %s", quotearg (tmpname));
+	  pfatal ("Can't open stream for file %s", quotearg (TMPEDNAME));
       }
 
     for (;;) {
@@ -2451,7 +2451,7 @@ do_ed_script (char const *inname, char c
       write_fatal ();
 
     if (lseek (tmpfd, 0, SEEK_SET) == -1)
-      pfatal ("Can't rewind to the beginning of file %s", quotearg (tmpname));
+      pfatal ("Can't rewind to the beginning of file %s", quotearg (TMPEDNAME));
 
     if (inerrno != ENOENT)
       {
@@ -2480,7 +2480,6 @@ do_ed_script (char const *inname, char c
       }
 
     fclose (tmpfp);
-    safe_unlink (tmpname);
 
     if (ofp)
       {