tree cec646e60868d1711d367bfe49038546b6b650b0
parent 1306c980cf892bc17e7296d3e9ab8e9082f893a1
author Andrii Nakryiko <andrii@kernel.org> 1604550837 -0800
committer Alexei Starovoitov <ast@kernel.org> 1604630250 -0800

libbpf: Fix BTF data layout checks and allow empty BTF

Make data section layout checks stricter, disallowing overlap of types and
strings data.

Additionally, allow BTFs with no type data. There is nothing inherently wrong
with having BTF with no types (put potentially with some strings). This could
be a situation with kernel module BTFs, if module doesn't introduce any new
type information.

Also fix invalid offset alignment check for btf->hdr->type_off.

Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-8-andrii@kernel.org