2 Commits

Author	SHA1	Message	Date
Andrii Nakryiko	197afc6314	libbpf: Don't attempt to load unused subprog as an entry-point BPF program ... If BPF code contains unused BPF subprogram and there are no other subprogram calls (which can realistically happen in real-world applications given sufficiently smart Clang code optimizations), libbpf will erroneously assume that subprograms are entry-point programs and will attempt to load them with UNSPEC program type. Fix by not relying on subcall instructions and rather detect it based on the structure of BPF object's sections. Fixes: 9a94f277c4fb ("tools: libbpf: restore the ability to load programs from .text section") Reported-by: Dmitrii Banshchikov <dbanschikov@fb.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20201107000251.256821-1-andrii@kernel.org	2020-11-09 22:15:23 +01:00
Andrii Nakryiko	a08c02f8d4	selftests/bpf: Add selftest for multi-prog sections and bpf-to-bpf calls ... Add a selftest excercising bpf-to-bpf subprogram calls, as well as multiple entry-point BPF programs per section. Also make sure that BPF CO-RE works for such set ups both for sub-programs and for multi-entry sections. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200903203542.15944-8-andriin@fb.com	2020-09-03 17:14:40 -07:00