last-modified: fix use of uninitialized memory
git-last-modified(1) uses a scratch bitmap to keep track of paths that have been changed between commits. To avoid reallocating a bitmap on each call of process_parent(), the scratch bitmap is kept and reused. Although, it seems an incorrect length is passed to memset(3). `struct bitmap` uses `eword_t` to for internal storage. This type is typedef'd to uint64_t. To fully zero the memory used by the bitmap, multiply the length (saved in `struct bitmap::word_alloc`) by the size of `eword_t`. Reported-by: Anders Kaseorg <andersk@mit.edu> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Toon Claes <toon@iotcl.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Toon Claes committed
Nov 28, 2025 at 17:37 UTC
fe4e60759bfbf4eaca17949d3bbb204bb5c908a2
1 file changed
+1
-1
builtin/last-modified.c
+1
-1
index b0ecbdc540..cc5fd2e795 100644
--- a/builtin/last-modified.c
+++ b/builtin/last-modified.c
@@ -327,7 +327,7 @@ static void process_parent(struct last_modified *lm,
if (!(parent->object.flags & PARENT1))
active_paths_free(lm, parent);
- memset(lm->scratch->words, 0x0, lm->scratch->word_alloc);
+ memset(lm->scratch->words, 0x0, lm->scratch->word_alloc * sizeof(eword_t));
diff_queue_clear(&diff_queued_diff);
}