tools: libbpf: handle NULL program gracefully in bpf_program__nth_fd()

bpf_map__fd() handles NULL map gracefully and returns -EINVAL.
bpf_program__fd() and bpf_program__nth_fd() crash in this case.
Make the behaviour more consistent by validating prog pointer
as well.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Jakub Kicinski 2018-07-26 14:32:18 -07:00 committed by Daniel Borkmann
parent 2367bd99f6
commit 1e960043e8

View File

@ -1991,6 +1991,9 @@ int bpf_program__nth_fd(struct bpf_program *prog, int n)
{
int fd;
if (!prog)
return -EINVAL;
if (n >= prog->instances.nr || n < 0) {
pr_warning("Can't get the %dth fd from program %s: only %d instances\n",
n, prog->section_name, prog->instances.nr);