Re: [PATCH 1/1] Don't free remote->name after fetch
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jun 13, 2016, 22:25 UTC
- Message-ID
- <xmqqbn34buak.fsf@gitster.mtv.corp.google.com>
- In-Reply-To
- <1465841837-31604-1-git-send-email-kmcguigan@twopensource.com>
kmcguigan@twopensource.com writes:
Show 7 quoted lines
> From: Keith McGuigan <kmcguigan@twopensource.com> > > The string_list gets populated with the names from the remotes[] array, > which are not dup'd and the list does not own. > > Signed-of-by: Keith McGuigan <kmcguigan@twopensource.com> > ---
For names that come from remote_get()->name, e.g.
static int get_one_remote_for_fetch(struct remote *remote, void *priv)
{
struct string_list *list = priv;
if (!remote->skip_default_update)
string_list_append(list, remote->name);
return 0;
}you are correct that this is borrowed memory we are not allowed to free. But is borrowing from remote->name the only way this list is populated? For example, what happens in add_remote_or_group(), which does this?
struct remote_group_data {
const char *name;
struct string_list *list;
}; static int get_remote_group(const char *key, const char *value, void *priv)
{
struct remote_group_data *g = priv; if (skip_prefix(key, "remotes.", &key) && !strcmp(key, g->name)) {
/* split list by white space */
while (*value) {
size_t wordlen = strcspn(value, " \t\n"); if (wordlen >= 1)
string_list_append(g->list,
xstrndup(value, wordlen));This newly allocated piece of memory is held by g->list, which was...
value += wordlen + (value[wordlen] != '\0');
}
} return 0;
} static int add_remote_or_group(const char *name, struct string_list *list)
{
int prev_nr = list->nr;
struct remote_group_data g;
g.name = name; g.list = list;... passed as a callback parameter from here.
git_config(get_remote_group, &g);
if (list->nr == prev_nr) {
struct remote *remote = remote_get(name);
if (!remote_is_configured(remote))
return 0;
string_list_append(list, remote->name);This makes remote->name borrowed, which we cannot free() as you point out.
}
return 1;
}So, while I agree that many should not be freed, this change makes the code leak some at the same time.
Show 16 quoted lines
> builtin/fetch.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/builtin/fetch.c b/builtin/fetch.c > index 630ae6a1bb78..181da5a2e7a3 100644 > --- a/builtin/fetch.c > +++ b/builtin/fetch.c > @@ -1347,8 +1347,6 @@ int cmd_fetch(int argc, const char **argv, const char *prefix) > argv_array_clear(&options); > } > > - /* All names were strdup()ed or strndup()ed */ > - list.strdup_strings = 1; > string_list_clear(&list, 0); > > close_all_packs();