@matheusbsbs / matheus-bagliano / commits / 3aef7a05ad

git: fix leaking argv when handling builtins

In `handle_builtin()` we may end up creating an ad-hoc argv array in case we see that the command line contains the "--help" parameter. In this case we observe two memory leaks though: - We leak the `struct strvec` itself because we directly exit after calling `run_builtin()`, without bothering about any cleanups. - Even if we free'd that vector we'd end up leaking some of its strings because `run_builtin()` will modify the array. Plug both of these leaks. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Patrick Steinhardt committed Sep 26, 2024 at 13:46 UTC 3aef7a05adb2868118181eb5605fffa65a9af2c8

2 files changed +20 -3

git.c

+19 -3

@@ -711,6 +711,7 @@ static void strip_extension(const char **argv)

711 static void handle_builtin(int argc, const char **argv)

712 {

713 struct strvec args = STRVEC_INIT;

714 + const char **argv_copy = NULL;

715 const char *cmd;

716 struct cmd_struct *builtin;

717

@@ -731,13 +732,28 @@ static void handle_builtin(int argc, const char **argv)

732 }

733

734 argc++;

734 - argv = args.v;

735 +

736 + /*

737 + * `run_builtin()` will modify the argv array, so we need to

738 + * create a shallow copy such that we can free all of its

739 + * strings.

740 + */

741 + CALLOC_ARRAY(argv_copy, argc + 1);

742 + COPY_ARRAY(argv_copy, args.v, argc);

743 +

744 + argv = argv_copy;

745 }

746

747 builtin = get_builtin(cmd);

738 - if (builtin)

739 - exit(run_builtin(builtin, argc, argv));

748 + if (builtin) {

749 + int ret = run_builtin(builtin, argc, argv);

750 + strvec_clear(&args);

751 + free(argv_copy);

752 + exit(ret);

753 + }

754 +

755 strvec_clear(&args);

756 + free(argv_copy);

757 }

758

759 static void execv_dashed_external(const char **argv)

t/t0012-help.sh

@@ -2,6 +2,7 @@

3 test_description='help'

5 +TEST_PASSES_SANITIZE_LEAK=true

6 . ./test-lib.sh

8 configure_help () {