From: Tony Ambardar <tony.ambardar@gmail.com> mainline inclusion from mainline-v6.12-rc1 commit da18bfa59d403040d8bcba1284285916fe9e4425 category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8335 CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ---------------------------------------------------------------------- New split BTF needs to preserve base's endianness. Similarly, when creating a distilled BTF, we need to preserve original endianness. Fix by updating libbpf's btf__distill_base() and btf_new_empty() to retain the byte order of any source BTF objects when creating new ones. Fixes: ba451366bf44 ("libbpf: Implement basic split BTF support") Fixes: 58e185a0dc35 ("libbpf: Add btf__distill_base() creating split BTF with distilled base BTF") Reported-by: Song Liu <song@kernel.org> Reported-by: Eduard Zingerman <eddyz87@gmail.com> Suggested-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/6358db36c5f68b07873a0a5be2d062b1af5ea5f8.camel@g... Link: https://lore.kernel.org/bpf/20240830095150.278881-1-tony.ambardar@gmail.com Signed-off-by: Luo Gengkun <luogengkun2@huawei.com> --- tools/lib/bpf/btf.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index ed64b5c207b8..f433a5282042 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -837,6 +837,7 @@ static struct btf *btf_new_empty(struct btf *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->swapped_endian = base_btf->swapped_endian; } /* +1 for empty string at offset 0 */ @@ -5226,6 +5227,9 @@ int btf__distill_base(const struct btf *src_btf, struct btf **new_base_btf, new_base = btf__new_empty(); if (!new_base) return libbpf_err(-ENOMEM); + + btf__set_endianness(new_base, btf__endianness(src_btf)); + dist.id_map = calloc(n, sizeof(*dist.id_map)); if (!dist.id_map) { err = -ENOMEM; -- 2.34.1