From: Andrzej Hunt <ajrhunt@xxxxxxxxxx>
cmd_for_each_repo() copies argv into args (a strvec), which is later
passed into run_command_on_repo(), which in turn copies that strvec onto
the end of child.args. The initial copy is unnecessary (we never modify
args). We therefore choose to just pass argv directly into
run_command_on_repo(), which lets us avoid the copy and fixes the leak.
LSAN output from t0068:
Direct leak of 192 byte(s) in 1 object(s) allocated from:
#0 0x7f63bd4ab8b0 in realloc (/usr/lib64/libasan.so.4+0xdc8b0)
#1 0x98d7e6 in xrealloc wrapper.c:126
#2 0x916914 in strvec_push_nodup strvec.c:19
#3 0x916a6e in strvec_push strvec.c:26
#4 0x4be4eb in cmd_for_each_repo builtin/for-each-repo.c:49
#5 0x410dcd in run_builtin git.c:475
#6 0x410dcd in handle_builtin git.c:729
#7 0x414087 in run_argv git.c:818
#8 0x414087 in cmd_main git.c:949
#9 0x40e9ec in main common-main.c:52
#10 0x7f63bc9fa349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 22 byte(s) in 2 object(s) allocated from:
#0 0x7f63bd445e30 in __interceptor_strdup (/usr/lib64/libasan.so.4+0x76e30)
#1 0x98d698 in xstrdup wrapper.c:29
#2 0x916a63 in strvec_push strvec.c:26
#3 0x4be4eb in cmd_for_each_repo builtin/for-each-repo.c:49
#4 0x410dcd in run_builtin git.c:475
#5 0x410dcd in handle_builtin git.c:729
#6 0x414087 in run_argv git.c:818
#7 0x414087 in cmd_main git.c:949
#8 0x40e9ec in main common-main.c:52
#9 0x7f63bc9fa349 in __libc_start_main (/lib64/libc.so.6+0x24349)
See also discussion about the original implementation below - this code
appears to have evolved from a callback explaining the double-strvec-copy
pattern, but there's no strong reason to keep that now:
https://lore.kernel.org/git/68bbeca5-314b-08ee-ef36-040e3f3814e9@xxxxxxxxx/
Signed-off-by: Andrzej Hunt <andrzej@xxxxxxxxx>
---
builtin/for-each-repo.c | 14 ++++----------
1 file changed, 4 insertions(+), 10 deletions(-)
diff --git a/builtin/for-each-repo.c b/builtin/for-each-repo.c
index 52be64a437..fd86e5a861 100644
--- a/builtin/for-each-repo.c
+++ b/builtin/for-each-repo.c
@@ -10,18 +10,16 @@ static const char * const for_each_repo_usage[] = {
NULL
};
-static int run_command_on_repo(const char *path,
- void *cbdata)
+static int run_command_on_repo(const char *path, int argc, const char ** argv)
{
int i;
struct child_process child = CHILD_PROCESS_INIT;
- struct strvec *args = (struct strvec *)cbdata;
child.git_cmd = 1;
strvec_pushl(&child.args, "-C", path, NULL);
- for (i = 0; i < args->nr; i++)
- strvec_push(&child.args, args->v[i]);
+ for (i = 0; i < argc; i++)
+ strvec_push(&child.args, argv[i]);
return run_command(&child);
}
@@ -29,37 +27,33 @@ static int run_command_on_repo(const char *path,
int cmd_for_each_repo(int argc, const char **argv, const char *prefix)
{
static const char *config_key = NULL;
int i, result = 0;
const struct string_list *values;
- struct strvec args = STRVEC_INIT;
const struct option options[] = {
OPT_STRING(0, "config", &config_key, N_("config"),
N_("config key storing a list of repository paths")),
OPT_END()
};
argc = parse_options(argc, argv, prefix, options, for_each_repo_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
if (!config_key)
die(_("missing --config=<config>"));
- for (i = 0; i < argc; i++)
- strvec_push(&args, argv[i]);
-
values = repo_config_get_value_multi(the_repository,
config_key);
/*
* Do nothing on an empty list, which is equivalent to the case
* where the config variable does not exist at all.
*/
if (!values)
return 0;
for (i = 0; !result && i < values->nr; i++)
- result = run_command_on_repo(values->items[i].string, &args);
+ result = run_command_on_repo(values->items[i].string, argc, argv);
return result;
}
--
2.26.2
