diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index 1082d919fd..dab2fdc2a6 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c
@@ -482,6 +482,7 @@ static int real_merge(struct merge_tree_options *o,
 			die(_("refusing to merge unrelated histories"));
 		merge_bases = reverse_commit_list(merge_bases);
 		merge_incore_recursive(&opt, merge_bases, parent1, parent2, &result);
+		free_commit_list(merge_bases);
 	}
 
 	if (result.clean < 0)
diff --git a/builtin/merge.c b/builtin/merge.c
index 682c6ed868..1120a6e2f8 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -746,6 +746,8 @@ static int try_merge_strategy(const char *strategy, struct commit_list *common,
 		else
 			clean = merge_recursive(&o, head, remoteheads->item,
 						reversed, &result);
+		free_commit_list(reversed);
+
 		if (clean < 0) {
 			rollback_lock_file(&lock);
 			return 2;
diff --git a/commit.c b/commit.c
index f674eca320..1386b12df1 100644
--- a/commit.c
+++ b/commit.c
@@ -680,7 +680,7 @@ unsigned commit_list_count(const struct commit_list *l)
 	return c;
 }
 
-struct commit_list *copy_commit_list(struct commit_list *list)
+struct commit_list *copy_commit_list(const struct commit_list *list)
 {
 	struct commit_list *head = NULL;
 	struct commit_list **pp = &head;
diff --git a/commit.h b/commit.h
index 442e50ff24..acabb05785 100644
--- a/commit.h
+++ b/commit.h
@@ -181,7 +181,7 @@ struct commit_list *commit_list_insert_by_date(struct commit *item,
 void commit_list_sort_by_date(struct commit_list **list);
 
 /* Shallow copy of the input list */
-struct commit_list *copy_commit_list(struct commit_list *list);
+struct commit_list *copy_commit_list(const struct commit_list *list);
 
 /* Modify list in-place to reverse it, returning new head; list will be tail */
 struct commit_list *reverse_commit_list(struct commit_list *list);
diff --git a/log-tree.c b/log-tree.c
index 41416de4e3..91b96d83a0 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -1047,6 +1047,7 @@ static int do_remerge_diff(struct rev_info *opt,
 	log_tree_diff_flush(opt);
 
 	/* Cleanup */
+	free_commit_list(bases);
 	cleanup_additional_headers(&opt->diffopt);
 	strbuf_release(&parent1_desc);
 	strbuf_release(&parent2_desc);
diff --git a/merge-ort-wrappers.c b/merge-ort-wrappers.c
index 4acedf3c33..d6f6135996 100644
--- a/merge-ort-wrappers.c
+++ b/merge-ort-wrappers.c
@@ -48,7 +48,7 @@ int merge_ort_nonrecursive(struct merge_options *opt,
 int merge_ort_recursive(struct merge_options *opt,
 			struct commit *side1,
 			struct commit *side2,
-			struct commit_list *merge_bases,
+			const struct commit_list *merge_bases,
 			struct commit **result)
 {
 	struct tree *head = repo_get_commit_tree(opt->repo, side1);
diff --git a/merge-ort-wrappers.h b/merge-ort-wrappers.h
index 0c4c57adbb..90af1f69c5 100644
--- a/merge-ort-wrappers.h
+++ b/merge-ort-wrappers.h
@@ -19,7 +19,7 @@ int merge_ort_nonrecursive(struct merge_options *opt,
 int merge_ort_recursive(struct merge_options *opt,
 			struct commit *h1,
 			struct commit *h2,
-			struct commit_list *ancestors,
+			const struct commit_list *ancestors,
 			struct commit **result);
 
 #endif
diff --git a/merge-ort.c b/merge-ort.c
index eaede6cead..8ed8a4c9dc 100644
--- a/merge-ort.c
+++ b/merge-ort.c
@@ -5071,11 +5071,12 @@ redo:
  * Originally from merge_recursive_internal(); somewhat adapted, though.
  */
 static void merge_ort_internal(struct merge_options *opt,
-			       struct commit_list *merge_bases,
+			       const struct commit_list *_merge_bases,
 			       struct commit *h1,
 			       struct commit *h2,
 			       struct merge_result *result)
 {
+	struct commit_list *merge_bases = copy_commit_list(_merge_bases);
 	struct commit *next;
 	struct commit *merged_merge_bases;
 	const char *ancestor_name;
@@ -5085,7 +5086,7 @@ static void merge_ort_internal(struct merge_options *opt,
 		if (repo_get_merge_bases(the_repository, h1, h2,
 					 &merge_bases) < 0) {
 			result->clean = -1;
-			return;
+			goto out;
 		}
 		/* See merge-ort.h:merge_incore_recursive() declaration NOTE */
 		merge_bases = reverse_commit_list(merge_bases);
@@ -5129,7 +5130,7 @@ static void merge_ort_internal(struct merge_options *opt,
 		opt->branch2 = "Temporary merge branch 2";
 		merge_ort_internal(opt, NULL, prev, next, result);
 		if (result->clean < 0)
-			return;
+			goto out;
 		opt->branch1 = saved_b1;
 		opt->branch2 = saved_b2;
 		opt->priv->call_depth--;
@@ -5152,6 +5153,9 @@ static void merge_ort_internal(struct merge_options *opt,
 					result);
 	strbuf_release(&merge_base_abbrev);
 	opt->ancestor = NULL;  /* avoid accidental re-use of opt->ancestor */
+
+out:
+	free_commit_list(merge_bases);
 }
 
 void merge_incore_nonrecursive(struct merge_options *opt,
@@ -5181,7 +5185,7 @@ void merge_incore_nonrecursive(struct merge_options *opt,
 }
 
 void merge_incore_recursive(struct merge_options *opt,
-			    struct commit_list *merge_bases,
+			    const struct commit_list *merge_bases,
 			    struct commit *side1,
 			    struct commit *side2,
 			    struct merge_result *result)
diff --git a/merge-ort.h b/merge-ort.h
index ce56ec1a78..6af97c0828 100644
--- a/merge-ort.h
+++ b/merge-ort.h
@@ -59,7 +59,7 @@ struct merge_result {
  *           first", 2006-08-09)
  */
 void merge_incore_recursive(struct merge_options *opt,
-			    struct commit_list *merge_bases,
+			    const struct commit_list *merge_bases,
 			    struct commit *side1,
 			    struct commit *side2,
 			    struct merge_result *result);
diff --git a/merge-recursive.c b/merge-recursive.c
index 832c8ef3f3..1ac0316cce 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -3633,15 +3633,16 @@ static int merge_trees_internal(struct merge_options *opt,
 static int merge_recursive_internal(struct merge_options *opt,
 				    struct commit *h1,
 				    struct commit *h2,
-				    struct commit_list *merge_bases,
+				    const struct commit_list *_merge_bases,
 				    struct commit **result)
 {
+	struct commit_list *merge_bases = copy_commit_list(_merge_bases);
 	struct commit_list *iter;
 	struct commit *merged_merge_bases;
 	struct tree *result_tree;
-	int clean;
 	const char *ancestor_name;
 	struct strbuf merge_base_abbrev = STRBUF_INIT;
+	int ret;
 
 	if (show(opt, 4)) {
 		output(opt, 4, _("Merging:"));
@@ -3651,8 +3652,10 @@ static int merge_recursive_internal(struct merge_options *opt,
 
 	if (!merge_bases) {
 		if (repo_get_merge_bases(the_repository, h1, h2,
-					 &merge_bases) < 0)
-			return -1;
+					 &merge_bases) < 0) {
+			ret = -1;
+			goto out;
+		}
 		merge_bases = reverse_commit_list(merge_bases);
 	}
 
@@ -3702,14 +3705,18 @@ static int merge_recursive_internal(struct merge_options *opt,
 		opt->branch1 = "Temporary merge branch 1";
 		opt->branch2 = "Temporary merge branch 2";
 		if (merge_recursive_internal(opt, merged_merge_bases, iter->item,
-					     NULL, &merged_merge_bases) < 0)
-			return -1;
+					     NULL, &merged_merge_bases) < 0) {
+			ret = -1;
+			goto out;
+		}
 		opt->branch1 = saved_b1;
 		opt->branch2 = saved_b2;
 		opt->priv->call_depth--;
 
-		if (!merged_merge_bases)
-			return err(opt, _("merge returned no commit"));
+		if (!merged_merge_bases) {
+			ret = err(opt, _("merge returned no commit"));
+			goto out;
+		}
 	}
 
 	/*
@@ -3726,17 +3733,16 @@ static int merge_recursive_internal(struct merge_options *opt,
 		repo_read_index(opt->repo);
 
 	opt->ancestor = ancestor_name;
-	clean = merge_trees_internal(opt,
-				     repo_get_commit_tree(opt->repo, h1),
-				     repo_get_commit_tree(opt->repo, h2),
-				     repo_get_commit_tree(opt->repo,
-							  merged_merge_bases),
-				     &result_tree);
-	strbuf_release(&merge_base_abbrev);
+	ret = merge_trees_internal(opt,
+				   repo_get_commit_tree(opt->repo, h1),
+				   repo_get_commit_tree(opt->repo, h2),
+				   repo_get_commit_tree(opt->repo,
+							merged_merge_bases),
+				   &result_tree);
 	opt->ancestor = NULL;  /* avoid accidental re-use of opt->ancestor */
-	if (clean < 0) {
+	if (ret < 0) {
 		flush_output(opt);
-		return clean;
+		goto out;
 	}
 
 	if (opt->priv->call_depth) {
@@ -3745,7 +3751,11 @@ static int merge_recursive_internal(struct merge_options *opt,
 		commit_list_insert(h1, &(*result)->parents);
 		commit_list_insert(h2, &(*result)->parents->next);
 	}
-	return clean;
+
+out:
+	strbuf_release(&merge_base_abbrev);
+	free_commit_list(merge_bases);
+	return ret;
 }
 
 static int merge_start(struct merge_options *opt, struct tree *head)
@@ -3827,7 +3837,7 @@ int merge_trees(struct merge_options *opt,
 int merge_recursive(struct merge_options *opt,
 		    struct commit *h1,
 		    struct commit *h2,
-		    struct commit_list *merge_bases,
+		    const struct commit_list *merge_bases,
 		    struct commit **result)
 {
 	int clean;
@@ -3895,6 +3905,7 @@ int merge_recursive_generic(struct merge_options *opt,
 	repo_hold_locked_index(opt->repo, &lock, LOCK_DIE_ON_ERROR);
 	clean = merge_recursive(opt, head_commit, next_commit, ca,
 				result);
+	free_commit_list(ca);
 	if (clean < 0) {
 		rollback_lock_file(&lock);
 		return clean;
diff --git a/merge-recursive.h b/merge-recursive.h
index 839eb6436e..3136c7cc2d 100644
--- a/merge-recursive.h
+++ b/merge-recursive.h
@@ -104,7 +104,7 @@ int merge_trees(struct merge_options *opt,
 int merge_recursive(struct merge_options *opt,
 		    struct commit *h1,
 		    struct commit *h2,
-		    struct commit_list *merge_bases,
+		    const struct commit_list *merge_bases,
 		    struct commit **result);
 
 /*
diff --git a/sequencer.c b/sequencer.c
index 20807ea7e5..131443c242 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -4315,6 +4315,7 @@ leave_merge:
 	strbuf_release(&ref_name);
 	rollback_lock_file(&lock);
 	free_commit_list(to_merge);
+	free_commit_list(bases);
 	return ret;
 }
 
diff --git a/t/t3430-rebase-merges.sh b/t/t3430-rebase-merges.sh
index 59b5d6b6f2..36ca126bcd 100755
--- a/t/t3430-rebase-merges.sh
+++ b/t/t3430-rebase-merges.sh
@@ -21,6 +21,7 @@ Initial setup:
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-rebase.sh
 . "$TEST_DIRECTORY"/lib-log-graph.sh
diff --git a/t/t6402-merge-rename.sh b/t/t6402-merge-rename.sh
index 2738b50c2a..729aac9842 100755
--- a/t/t6402-merge-rename.sh
+++ b/t/t6402-merge-rename.sh
@@ -4,6 +4,7 @@ test_description='Merge-recursive merging renames'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 modify () {
diff --git a/t/t6430-merge-recursive.sh b/t/t6430-merge-recursive.sh
index ca15e6dd6d..555f00f78a 100755
--- a/t/t6430-merge-recursive.sh
+++ b/t/t6430-merge-recursive.sh
@@ -5,6 +5,7 @@ test_description='merge-recursive backend test'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-merge.sh
 
diff --git a/t/t6436-merge-overwrite.sh b/t/t6436-merge-overwrite.sh
index 4f4376421e..ccc620477d 100755
--- a/t/t6436-merge-overwrite.sh
+++ b/t/t6436-merge-overwrite.sh
@@ -7,6 +7,7 @@ Do not overwrite changes.'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup' '
diff --git a/t/t7611-merge-abort.sh b/t/t7611-merge-abort.sh
index d6975ca48d..992a8f9874 100755
--- a/t/t7611-merge-abort.sh
+++ b/t/t7611-merge-abort.sh
@@ -25,6 +25,7 @@ Next, test git merge --abort with the following variables:
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup' '