From 05e717d556e5e1c7cdf69c7375d19bef226fc0dc Mon Sep 17 00:00:00 2001
From: Rubén Justo <rjusto@gmail.com>
Date: Sat, 17 Jun 2023 08:40:43 +0200
Subject: rev-parse: fix a leak with --abbrev-ref
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To handle "--abbrev-ref" we use shorten_unambiguous_ref().  This
function takes a refname and returns a shortened refname, which is a
newly allocated string that needs to be freed.

Unfortunately, the refname variable is reused to receive the shortened
one.  Therefore, we lose the original refname, which needs to be freed
as well, producing a leak.

This leak can be reviewed with:

   $ for a in {1..10}; do git branch foo_${a}; done
   $ git rev-parse --abbrev-ref refs/heads/foo_{1..10}

   Direct leak of 171 byte(s) in 10 object(s) allocated from:
       ... in xstrdup wrapper.c
       ... in expand_ref refs.c
       ... in repo_dwim_ref refs.c
       ... in show_rev builtin/rev-parse.c
       ... in cmd_rev_parse builtin/rev-parse.c
       ... in run_builtin git.c

We have this leak since a45d34691e (rev-parse: --abbrev-ref option to
shorten ref name, 2009-04-13) when "--abbrev-ref" was introduced.

Let's fix it.

Signed-off-by: Rubén Justo <rjusto@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin/rev-parse.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

(limited to 'builtin')

diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
index 852e49e340..d2eb239a08 100644
--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c
@@ -156,9 +156,12 @@ static void show_rev(int type, const struct object_id *oid, const char *name)
 				 */
 				break;
 			case 1: /* happy */
-				if (abbrev_ref)
+				if (abbrev_ref) {
+					char *old = full;
 					full = shorten_unambiguous_ref(full,
 						abbrev_ref_strict);
+					free(old);
+				}
 				show_with_type(type, full);
 				break;
 			default: /* ambiguous */
-- 
cgit v1.3


From 2935a9783604fec3c7735a791323574354b4b75f Mon Sep 17 00:00:00 2001
From: Rubén Justo <rjusto@gmail.com>
Date: Sat, 17 Jun 2023 08:41:22 +0200
Subject: branch: fix a leak in cmd_branch
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

In 98e7ab6d42 (for-each-ref: delay parsing of --sort=<atom> options,
2021-10-20) a new string_list was introduced to accumulate any
"branch.sort" setting.

That string_list is cleared in ref_sorting_options(), which is only
called when processing the "--list" sub-command.  Therefore, with other
sub-command, while having any sort option set, a leak is produced, e.g.:

   $ git config branch.sort invalid_sort_option
   $ git branch --edit-description

   Direct leak of 384 byte(s) in 1 object(s) allocated from:
       ... in xrealloc wrapper.c
       ... in string_list_append_nodup string-list.c
       ... in string_list_append string-list.c
       ... in git_branch_config builtin/branch.c
       ... in configset_iter config.c
       ... in repo_config config.c
       ... in git_config config.c
       ... in cmd_branch builtin/branch.c
       ... in run_builtin git.c

   Indirect leak of 20 byte(s) in 1 object(s) allocated from:
       ... in xstrdup wrapper.c
       ... in string_list_append string-list.c
       ... in git_branch_config builtin/branch.c
       ... in configset_iter config.c
       ... in repo_config config.c
       ... in git_config config.c
       ... in cmd_branch builtin/branch.c
       ... in run_builtin git.c

We don't have a common clean-up section in cmd_branch().  To avoid
refactoring, keep the fix simple, and while we find a better solution
which hopefuly will avoid entirely that string_list, when no sort
options are needed; let's squelch the leak sanitizer using UNLEAK().

Signed-off-by: Rubén Justo <rjusto@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin/branch.c | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'builtin')

diff --git a/builtin/branch.c b/builtin/branch.c
index e6c2655af6..075e580d22 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -832,6 +832,8 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 	if (list)
 		setup_auto_pager("branch", 1);
 
+	UNLEAK(sorting_options);
+
 	if (delete) {
 		if (!argc)
 			die(_("branch name required"));
-- 
cgit v1.3