Commit: patch 9.1.1734: Memory leak when allocating match fails

[Christian Brabandt]

patch 9.1.1734: Memory leak when allocating match fails

Commit: https://github.com/vim/vim/commit/37e77282949786bb178c8fb8d6717afcaa40688e
Author: Damien Lejay <dam...@lejay.be>
Date: Fri Sep 5 17:29:31 2025 +0200

patch 9.1.1734: Memory leak when allocating match fails

Problem: Memory leak when allocating match fails
Solution: Initialize m to NULL and centralize cleanup via goto fail to
avoid leaks on early returns (Damien Lejay)

closes: #18204

Signed-off-by: Damien Lejay <dam...@lejay.be>
Signed-off-by: Hirohito Higashi <h.eas...@gmail.com>
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/match.c b/src/match.c
index ef2587947..3b664bdb8 100644
--- a/src/match.c
+++ b/src/match.c
@@ -21,7 +21,7 @@
* Add match to the match list of window "wp".
* If "pat" is not NULL the pattern will be highlighted with the group "grp"
* with priority "prio".
- * If "pos_list" is not NULL the list of posisions defines the highlights.
+ * If "pos_list" is not NULL the list of positions defines the highlights.
* Optionally, a desired ID "id" can be specified (greater than or equal to 1).
* If no particular ID is desired, -1 must be specified for "id".
* Return ID of added match, -1 on failure.
@@ -38,7 +38,7 @@ match_add(
{
matchitem_T *cur;
matchitem_T *prev;
- matchitem_T *m;
+ matchitem_T *m = NULL;
int hlg_id;
regprog_T *regprog = NULL;
int rtype = UPD_SOME_VALID;
@@ -86,15 +86,12 @@ match_add(
// Build new match.
m = ALLOC_CLEAR_ONE(matchitem_T);
if (m == NULL)
- return -1;
+ goto fail;
if (pos_list != NULL && pos_list->lv_len > 0)
{
m->mit_pos_array = ALLOC_CLEAR_MULT(llpos_T, pos_list->lv_len);
if (m->mit_pos_array == NULL)
- {
- vim_free(m);
- return -1;
- }
+ goto fail;
m->mit_pos_count = pos_list->lv_len;
}
m->mit_id = id;
@@ -213,9 +210,13 @@ match_add(
return id;

fail:
- vim_free(m->mit_pattern);
- vim_free(m->mit_pos_array);
- vim_free(m);
+ vim_regfree(regprog);
+ if (m != NULL)
+ {
+ vim_free(m->mit_pattern);
+ vim_free(m->mit_pos_array);
+ vim_free(m);
+ }
return -1;
}

diff --git a/src/version.c b/src/version.c
index aea569a25..8cddb1271 100644
--- a/src/version.c
+++ b/src/version.c
@@ -724,6 +724,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 1734,
/**/
1733,
/**/