[PATCH 09/23] dir: fix off by one errors for ignored and untracked entries

[Patrick Steinhardt <ps@pks.im>]

In `treat_directory()` we perform some logic to handle ignored and
untracked entries. When populating a directory with entries we first
save the current number of ignored/untracked entries and then populate
new entries at the end of our arrays that keep track of those entries.
When we figure out that all entries have been ignored/are untracked we
then remove this tail of entries from those vectors again. But there is
an off by one error in both paths that causes us to not free the first
ignored and untracked entries, respectively.

Fix these off-by-one errors to plug the resulting leak. While at it,
massage the code a bit to match our modern code style.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
---
 dir.c                                              | 6 ++----
 t/t3011-common-prefixes-and-directory-traversal.sh | 1 +
 t/t7061-wtstatus-ignore.sh                         | 1 +
 t/t7521-ignored-mode.sh                            | 1 +
 4 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/dir.c b/dir.c
index 5a23376bdae..787bcb7a1a4 100644
--- a/dir.c
+++ b/dir.c
@@ -2135,8 +2135,7 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 			 */
 			state = path_none;
 		} else {
-			int i;
-			for (i = old_ignored_nr + 1; i<dir->ignored_nr; ++i)
+			for (int i = old_ignored_nr; i < dir->ignored_nr; i++)
 				FREE_AND_NULL(dir->ignored[i]);
 			dir->ignored_nr = old_ignored_nr;
 		}
@@ -2148,8 +2147,7 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 	 */
 	if ((dir->flags & DIR_SHOW_IGNORED_TOO) &&
 	    !(dir->flags & DIR_KEEP_UNTRACKED_CONTENTS)) {
-		int i;
-		for (i = old_untracked_nr + 1; i<dir->nr; ++i)
+		for (int i = old_untracked_nr; i < dir->nr; i++)
 			FREE_AND_NULL(dir->entries[i]);
 		dir->nr = old_untracked_nr;
 	}
diff --git a/t/t3011-common-prefixes-and-directory-traversal.sh b/t/t3011-common-prefixes-and-directory-traversal.sh
index 3da5b2b6e79..69e44c387fa 100755
--- a/t/t3011-common-prefixes-and-directory-traversal.sh
+++ b/t/t3011-common-prefixes-and-directory-traversal.sh
@@ -2,6 +2,7 @@
 
 test_description='directory traversal handling, especially with common prefixes'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup' '
diff --git a/t/t7061-wtstatus-ignore.sh b/t/t7061-wtstatus-ignore.sh
index 2f9bea9793c..64145a05b1f 100755
--- a/t/t7061-wtstatus-ignore.sh
+++ b/t/t7061-wtstatus-ignore.sh
@@ -2,6 +2,7 @@
 
 test_description='git-status ignored files'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 cat >expected <<\EOF
diff --git a/t/t7521-ignored-mode.sh b/t/t7521-ignored-mode.sh
index a88b02b06ed..edce10f998e 100755
--- a/t/t7521-ignored-mode.sh
+++ b/t/t7521-ignored-mode.sh
@@ -2,6 +2,7 @@
 
 test_description='git status ignored modes'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup initial commit and ignore file' '
-- 
2.46.0.551.gc5ee8f2d1c.dirty