From: Bram Moolenaar <Bram@vim.org>
Date: Fri, 28 Sep 2018 20:26:54 +0000 (+0200)
Subject: patch 8.1.0437: may access freed memory when syntax HL times out
X-Git-Tag: v8.1.0437
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=95892c27b242cdbc78e622c7a861a4e15aec7a30;p=vim

patch 8.1.0437: may access freed memory when syntax HL times out

Problem:    May access freed memory when syntax HL times out. (Philipp Gesang)
Solution:   Clear b_sst_first when clearing b_sst_array.
---

diff --git a/src/syntax.c b/src/syntax.c
index 8fb4e20e5..e54ec9a82 100644
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -1192,6 +1192,7 @@ syn_stack_free_block(synblock_T *block)
 	for (p = block->b_sst_first; p != NULL; p = p->sst_next)
 	    clear_syn_state(p);
 	VIM_CLEAR(block->b_sst_array);
+	block->b_sst_first = NULL;
 	block->b_sst_len = 0;
     }
 }
@@ -1323,9 +1324,6 @@ syn_stack_apply_changes_block(synblock_T *block, buf_T *buf)
     synstate_T	*p, *prev, *np;
     linenr_T	n;
 
-    if (block->b_sst_array == NULL)	/* nothing to do */
-	return;
-
     prev = NULL;
     for (p = block->b_sst_first; p != NULL; )
     {
@@ -1378,7 +1376,7 @@ syn_stack_cleanup(void)
     int		dist;
     int		retval = FALSE;
 
-    if (syn_block->b_sst_array == NULL || syn_block->b_sst_first == NULL)
+    if (syn_block->b_sst_first == NULL)
 	return retval;
 
     /* Compute normal distance between non-displayed entries. */
diff --git a/src/version.c b/src/version.c
index 7f21f2d80..55d3d8013 100644
--- a/src/version.c
+++ b/src/version.c
@@ -794,6 +794,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    437,
 /**/
     436,
 /**/