To: vim_dev@googlegroups.com
Subject: Patch 8.2.5164
Fcc: outbox
From: Bram Moolenaar <Bram@moolenaar.net>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
------------

Patch 8.2.5164
Problem:    Invalid memory access after diff buffer manipulations.
Solution:   Use zero offset when change removes all lines in a diff block.
Files:      src/diff.c, src/testdir/test_diffmode.vim


*** ../vim-8.2.5163/src/diff.c	2022-06-26 14:04:04.096859187 +0100
--- src/diff.c	2022-06-26 16:52:28.113205371 +0100
***************
*** 403,411 ****
  		// 2. 3. 4. 5.: inserted/deleted lines touching this diff.
  		if (deleted > 0)
  		{
  		    if (dp->df_lnum[idx] >= line1)
  		    {
- 			off = dp->df_lnum[idx] - lnum_deleted;
  			if (last <= line2)
  			{
  			    // 4. delete all lines of diff
--- 403,411 ----
  		// 2. 3. 4. 5.: inserted/deleted lines touching this diff.
  		if (deleted > 0)
  		{
+ 		    off = 0;
  		    if (dp->df_lnum[idx] >= line1)
  		    {
  			if (last <= line2)
  			{
  			    // 4. delete all lines of diff
***************
*** 426,431 ****
--- 426,432 ----
  			else
  			{
  			    // 5. delete lines at or just before top of diff
+ 			    off = dp->df_lnum[idx] - lnum_deleted;
  			    n = off;
  			    dp->df_count[idx] -= line2 - dp->df_lnum[idx] + 1;
  			    check_unchanged = TRUE;
***************
*** 434,440 ****
  		    }
  		    else
  		    {
- 			off = 0;
  			if (last < line2)
  			{
  			    // 2. delete at end of diff
--- 435,440 ----
*** ../vim-8.2.5163/src/testdir/test_diffmode.vim	2022-06-26 14:04:04.096859187 +0100
--- src/testdir/test_diffmode.vim	2022-06-26 16:52:06.629198006 +0100
***************
*** 1615,1619 ****
--- 1615,1631 ----
    %bwipe!
  endfunc
  
+ " This was causing invalid diff block values
+ " FIXME: somehow this causes a valgrind error when run directly but not when
+ " run as a test.
+ func Test_diff_manipulations()
+   set diff
+   split 0
+   sil! norm R
doobdeuR
doobdeuR
doobdeu
+ 
+   set nodiff
+   %bwipe!
+ endfunc
+ 
  
  " vim: shiftwidth=2 sts=2 expandtab
*** ../vim-8.2.5163/src/version.c	2022-06-26 14:04:04.096859187 +0100
--- src/version.c	2022-06-26 16:44:24.560990947 +0100
***************
*** 737,738 ****
--- 737,740 ----
  {   /* Add new patch number below this line */
+ /**/
+     5164,
  /**/

-- 
hundred-and-one symptoms of being an internet addict:
7. You finally do take that vacation, but only after buying a USB modem
   and a laptop.

 /// Bram Moolenaar -- Bram@Moolenaar.net -- http://www.Moolenaar.net   \\\
///                                                                      \\\
\\\        sponsor Vim, vote for features -- http://www.Vim.org/sponsor/ ///
 \\\            help me help AIDS victims -- http://ICCF-Holland.org    ///