Commit 4f596acc authored by Alan Maguire's avatar Alan Maguire Committed by Andrii Nakryiko
Browse files

libbpf: Fix parsing of multi-split BTF 



When creating multi-split BTF we correctly set the start string offset
to be the size of the base string section plus the base BTF start
string offset; the latter is needed for multi-split BTF since the
offset is non-zero there.

Unfortunately the BTF parsing case needed that logic and it was
missed.

Fixes: 4e29128a ("libbpf/btf: Fix string handling to support multi-split BTF")
Signed-off-by: default avatarAlan Maguire <alan.maguire@oracle.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20251104203309.318429-2-alan.maguire@oracle.com
parent b3387b31

tools/lib/bpf/btf.c

+2 −2
Original line number Diff line number Diff line
@@ -1061,7 +1061,7 @@ static struct btf *btf_new(const void *data, __u32 size, struct btf *base_btf, b 
	if (base_btf) {

		btf->base_btf = base_btf;

		btf->start_id = btf__type_cnt(base_btf);

		btf->start_str_off = base_btf->hdr->str_len;

		btf->start_str_off = base_btf->hdr->str_len + base_btf->start_str_off;

	}



	if (is_mmap) {
@@ -5818,7 +5818,7 @@ void btf_set_base_btf(struct btf *btf, const struct btf *base_btf) 
{

	btf->base_btf = (struct btf *)base_btf;

	btf->start_id = btf__type_cnt(base_btf);

	btf->start_str_off = base_btf->hdr->str_len;

	btf->start_str_off = base_btf->hdr->str_len + base_btf->start_str_off;

}



int btf__relocate(struct btf *btf, const struct btf *base_btf)