To: vim-dev@vim.org
Subject: Patch 5.7.028
Fcc: outbox
From: Bram Moolenaar <Bram@moolenaar.net>
------------

Patch 5.7.028
Problem:    Creating a backup or swap file could fail in rare situations.
Solution:   Use O_EXCL for open().
Files:	    src/fileio.c, src/memfile.c


*** ../vim-5.7.27/src/fileio.c	Thu Mar 29 21:39:51 2001
--- src/fileio.c	Fri Mar 30 12:11:30 2001
***************
*** 1532,1538 ****
  	    {
  		/* remove old backup, if present */
  		mch_remove(backup);
! 		bfd = mch_open((char *)backup, O_WRONLY|O_CREAT|O_EXTRA, 0666);
  		if (bfd < 0)
  		{
  		    vim_free(backup);
--- 1532,1539 ----
  	    {
  		/* remove old backup, if present */
  		mch_remove(backup);
! 		bfd = mch_open((char *)backup, O_WRONLY|O_CREAT|O_EXCL|O_EXTRA,
! 									0666);
  		if (bfd < 0)
  		{
  		    vim_free(backup);
***************
*** 2147,2153 ****
  	    int empty_fd;
  
  	    if (org == NULL
! 		    || (empty_fd = mch_open(org, O_CREAT | O_EXTRA, 0666)) < 0)
  	      EMSG("patchmode: can't touch empty original file");
  	    else
  	      close(empty_fd);
--- 2148,2155 ----
  	    int empty_fd;
  
  	    if (org == NULL
! 		    || (empty_fd = mch_open(org, O_CREAT | O_EXTRA | O_EXCL,
! 								   0666)) < 0)
  	      EMSG("patchmode: can't touch empty original file");
  	    else
  	      close(empty_fd);
***************
*** 2820,2826 ****
      fd_in = mch_open((char *)from, O_RDONLY|O_EXTRA, 0);
      if (fd_in == -1)
  	return -1;
!     fd_out = mch_open((char *)to, O_CREAT|O_TRUNC|O_WRONLY|O_EXTRA, 0666);
      if (fd_out == -1)
      {
  	close(fd_in);
--- 2822,2828 ----
      fd_in = mch_open((char *)from, O_RDONLY|O_EXTRA, 0);
      if (fd_in == -1)
  	return -1;
!     fd_out = mch_open((char *)to, O_CREAT|O_EXCL|O_WRONLY|O_EXTRA, 0666);
      if (fd_out == -1)
      {
  	close(fd_in);
*** ../vim-5.7.27/src/memfile.c	Tue Jan 11 16:19:43 2000
--- src/memfile.c	Tue Apr  3 11:47:46 2001
***************
*** 1213,1227 ****
  #endif
  
      /*
!      * try to open the file
       */
      mfp->mf_fd = open(
  #ifdef VMS
  	    vms_fixfilename(mfp->mf_fname),
  #else
  	    (char *)mfp->mf_fname,
  #endif
! 	    (trunc_file ? (O_CREAT | O_RDWR | O_TRUNC) : (O_RDONLY)) | O_EXTRA
  #if defined(UNIX) || defined(RISCOS)		 /* open in rw------- mode */
  		    , (mode_t)0600
  #endif
--- 1213,1229 ----
  #endif
  
      /*
!      * Try to open the file.  First delete any existing file.
       */
+     if (trunc_file)
+ 	mch_remove(mfp->mf_fname);
      mfp->mf_fd = open(
  #ifdef VMS
  	    vms_fixfilename(mfp->mf_fname),
  #else
  	    (char *)mfp->mf_fname,
  #endif
! 	    (trunc_file ? (O_CREAT | O_RDWR | O_EXCL) : (O_RDONLY)) | O_EXTRA
  #if defined(UNIX) || defined(RISCOS)		 /* open in rw------- mode */
  		    , (mode_t)0600
  #endif
*** ../vim-5.7.27/src/version.c	Thu Mar 29 21:39:51 2001
--- src/version.c	Tue Apr  3 11:48:06 2001
***************
*** 439,440 ****
--- 439,442 ----
  {   /* Add new patch number below this line */
+ /**/
+     28,
  /**/

-- 
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engineer, most normal people harbor an intense desire to _mate_ with them,
thus producing engineerlike children who will have high-paying jobs long
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				(Scott Adams - The Dilbert principle)

 ///  Bram Moolenaar -- Bram@moolenaar.net -- http://www.moolenaar.net  \\\
(((   Creator of Vim - http://www.vim.org -- ftp://ftp.vim.org/pub/vim   )))
 \\\  Help me helping AIDS orphans in Uganda - http://iccf-holland.org  ///