diff mbox series

[v5,03/16] ref-filter: clear reachable list pointers after freeing

Message ID cea1e88d35871f84d504a7e5eaa6186fcc6f46f0.1689023520.git.me@ttaylorr.com (mailing list archive)
State Accepted
Commit 311bfe18ce8563d0b1b571e9dc9eb35b97de3790
Headers show
Series refs: implement jump lists for packed backend | expand

Commit Message

Taylor Blau July 10, 2023, 9:12 p.m. UTC 
From: Jeff King <peff@peff.net>

In `reach_filter()`, we pop all commits from the reachable lists,
leaving them empty. But because we're operating on a list pointer that
was passed by value, the original `filter.reachable_from` and
`filter.unreachable_from` pointers are left dangling.

As is the case with the previous commit, nobody touches either of these
fields after calling `reach_filter()`, so leaving them dangling is OK.
But this future proofs against dangerous situations.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
---
 ref-filter.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/ref-filter.c b/ref-filter.c
index e0d03a9f8e9..4dd6575400c 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -2418,13 +2418,13 @@  void ref_array_clear(struct ref_array *array)
 #define EXCLUDE_REACHED 0
 #define INCLUDE_REACHED 1
 static void reach_filter(struct ref_array *array,
-			 struct commit_list *check_reachable,
+			 struct commit_list **check_reachable,
 			 int include_reached)
 {
 	int i, old_nr;
 	struct commit **to_clear;
 
-	if (!check_reachable)
+	if (!*check_reachable)
 		return;
 
 	CALLOC_ARRAY(to_clear, array->nr);
@@ -2434,7 +2434,7 @@  static void reach_filter(struct ref_array *array,
 	}
 
 	tips_reachable_from_bases(the_repository,
-				  check_reachable,
+				  *check_reachable,
 				  to_clear, array->nr,
 				  UNINTERESTING);
 
@@ -2455,8 +2455,8 @@  static void reach_filter(struct ref_array *array,
 
 	clear_commit_marks_many(old_nr, to_clear, ALL_REV_FLAGS);
 
-	while (check_reachable) {
-		struct commit *merge_commit = pop_commit(&check_reachable);
+	while (*check_reachable) {
+		struct commit *merge_commit = pop_commit(check_reachable);
 		clear_commit_marks(merge_commit, ALL_REV_FLAGS);
 	}
 
@@ -2553,8 +2553,8 @@  int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 	clear_contains_cache(&ref_cbdata.no_contains_cache);
 
 	/*  Filters that need revision walking */
-	reach_filter(array, filter->reachable_from, INCLUDE_REACHED);
-	reach_filter(array, filter->unreachable_from, EXCLUDE_REACHED);
+	reach_filter(array, &filter->reachable_from, INCLUDE_REACHED);
+	reach_filter(array, &filter->unreachable_from, EXCLUDE_REACHED);
 
 	save_commit_buffer = save_commit_buffer_orig;
 	return ret;