`type` field is supposed to directly point to the btf in functions like `btf_members()`. So I will make change only to `tname` field in this patch. On Wed, Aug 21, 2024 at 6:04 PM Soma Nakata <soma.nakata01@xxxxxxxxx> wrote: > > Hi, > > You're correct, I should add a NULL check. > > zfree(&map->st_ops->tname) causes error because tname has > `const` qualifier. > Also, I found st_ops->type has the same issue. > Therefore, I propose removing `const` from `tname` and `type` > fields of `struct bpf_struct_ops`, and duplicating them from btf. > > > > > Le 21/08/2024 à 08:46, Soma Nakata a écrit : > > > `tname` is returned by `btf__name_by_offset()` as well as `var_name`, > > > and these addresses point to strings in the btf. Since their locations > > > may change while loading the bpf program, using `strdup()` ensures > > > `tname` is safely stored. > > > > > > Signed-off-by: Soma Nakata <soma.nakata01@xxxxxxxxx> > > > --- > > > tools/lib/bpf/libbpf.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > > > index a3be6f8fac09..ece1f1af2cd4 100644 > > > --- a/tools/lib/bpf/libbpf.c > > > +++ b/tools/lib/bpf/libbpf.c > > > @@ -1423,7 +1423,7 @@ static int init_struct_ops_maps(struct bpf_object *obj, const char *sec_name, > > > memcpy(st_ops->data, > > > data->d_buf + vsi->offset, > > > type->size); > > > - st_ops->tname = tname; > > > + st_ops->tname = strdup(tname); > > > > Hi, > > > > Should a NULL check be added (as done a few lines above for the > > [cm]alloc()) and bpf_map__destroy() updated with a > > zfree(&map->st_ops->tname) ? > > > > CJ > > > > > st_ops->type = type; > > > st_ops->type_id = type_id; > > > > >
