builtin/help: fix leaks in `check_git_cmd()`
The `check_git_cmd()` function is declared to return a string constant. And while it sometimes does return a constant, it may also return an allocated string in two cases: - When handling aliases. This case is already marked with `UNLEAK()` to work around the leak. - When handling unknown commands in case "help.autocorrect" is enabled. This one is not marked with `UNLEAK()`. The function only has a single caller, so let's fix its return type to be non-constant, consistently return an allocated string and free it at its callsite to plug the leak. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt committed
Nov 20, 2024 at 14:39 UTC
2379b5c90038b2c334ff62cce62d50b4a8e78360
1 file changed
+7
-6
builtin/help.c
+7
-6
@@ -551,12 +551,12 @@ static void show_html_page(const char *page)
551
open_html(page_path.buf);
552
}
553
554
-static const char *check_git_cmd(const char* cmd)
554
+static char *check_git_cmd(const char *cmd)
555
{
556
char *alias;
557
558
if (is_git_command(cmd))
559
- return cmd;
559
+ return xstrdup(cmd);
560
561
alias = alias_lookup(cmd);
562
if (alias) {
@@ -589,14 +589,13 @@ static const char *check_git_cmd(const char* cmd)
589
die(_("bad alias.%s string: %s"), cmd,
590
split_cmdline_strerror(count));
591
free(argv);
592
- UNLEAK(alias);
592
return alias;
593
}
594
595
if (exclude_guides)
596
return help_unknown_cmd(cmd);
597
599
- return cmd;
598
+ return xstrdup(cmd);
599
}
600
601
static void no_help_format(const char *opt_mode, enum help_format fmt)
@@ -642,6 +641,7 @@ int cmd_help(int argc,
641
{
642
int nongit;
643
enum help_format parsed_help_format;
644
+ char *command = NULL;
645
const char *page;
646
647
argc = parse_options(argc, argv, prefix, builtin_help_options,
@@ -713,9 +713,9 @@ int cmd_help(int argc,
713
if (help_format == HELP_FORMAT_NONE)
714
help_format = parse_help_format(DEFAULT_HELP_FORMAT);
715
716
- argv[0] = check_git_cmd(argv[0]);
716
+ command = check_git_cmd(argv[0]);
717
718
- page = cmd_to_page(argv[0]);
718
+ page = cmd_to_page(command);
719
switch (help_format) {
720
case HELP_FORMAT_NONE:
721
case HELP_FORMAT_MAN:
@@ -729,5 +729,6 @@ int cmd_help(int argc,
729
break;
730
}
731
732
+ free(command);
733
return 0;
734
}