Re: [PATCH 03/28] fetch-pack: fix leaking sought refs

> Am 24.09.24 um 23:51 schrieb Jeff King:
> > From: Patrick Steinhardt <ps@pks.im>
> > diff --git a/transport.c b/transport.c
> > index 3c4714581f..1098bbd60e 100644
> > --- a/transport.c
> > +++ b/transport.c
> > @@ -414,7 +414,7 @@ static int fetch_refs_via_pack(struct transport *transport,
> >  	struct git_transport_data *data = transport->data;
> >  	struct ref *refs = NULL;
> >  	struct fetch_pack_args args;
> > -	struct ref *refs_tmp = NULL;
> > +	struct ref *refs_tmp = NULL, **to_fetch_dup = NULL;
> >
> >  	memset(&args, 0, sizeof(args));
> >  	args.uploadpack = data->options.uploadpack;
> > @@ -477,6 +477,14 @@ static int fetch_refs_via_pack(struct transport *transport,
> >  		goto cleanup;
> >  	}
> >
> > +	/*
> > +	 * Create a shallow copy of `sought` so that we can free all of its entries.
> > +	 * This is because `fetch_pack()` will modify the array to evict some
> > +	 * entries, but won't free those.
> > +	 */
> > +	DUP_ARRAY(to_fetch_dup, to_fetch, nr_heads);
> > +	to_fetch = to_fetch_dup;
> > +
> >  	refs = fetch_pack(&args, data->fd,
> >  			  refs_tmp ? refs_tmp : transport->remote_refs,
> >  			  to_fetch, nr_heads, &data->shallow,
> > @@ -500,6 +508,7 @@ static int fetch_refs_via_pack(struct transport *transport,
> >  		ret = -1;
> >  	data->conn = NULL;
> >
> > +	free(to_fetch_dup);
> 
> This makes a shallow copy and passes it to fetch_pack() and later to
> report_unmatched_refs().  It shields callers of fetch_refs_via_pack()
> from the effect of fetch_pack()'s NULLification.  This is what the
> commit message says would not work.  What am I missing?