This is a note to let you know that I've just added the patch titled
libbpf: never interpret subprogs in .text as entry programs
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
libbpf-never-interpret-subprogs-in-.text-as-entry-pr.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f720197e0bd0cd087091fd97b0c21b8ab1ec0a0f
Author: Andrii Nakryiko <andrii@xxxxxxxxxx>
Date: Thu Oct 10 14:17:30 2024 -0700
libbpf: never interpret subprogs in .text as entry programs
[ Upstream commit db089c9158c1d535a36dfc010e5db37fccea2561 ]
Libbpf pre-1.0 had a legacy logic of allowing singular non-annotated
(i.e., not having explicit SEC() annotation) function to be treated as
sole entry BPF program (unless there were other explicit entry
programs).
This behavior was dropped during libbpf 1.0 transition period (unless
LIBBPF_STRICT_SEC_NAME flag was unset in libbpf_mode). When 1.0 was
released and all the legacy behavior was removed, the bug slipped
through leaving this legacy behavior around.
Fix this for good, as it actually causes very confusing behavior if BPF
object file only has subprograms, but no entry programs.
Fixes: bd054102a8c7 ("libbpf: enforce strict libbpf 1.0 behaviors")
Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20241010211731.4121837-1-andrii@xxxxxxxxxx
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index d8b5304eac8cd..a0fb50718daef 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -3896,7 +3896,7 @@ static int bpf_object__collect_externs(struct bpf_object *obj)
static bool prog_is_subprog(const struct bpf_object *obj, const struct bpf_program *prog)
{
- return prog->sec_idx == obj->efile.text_shndx && obj->nr_programs > 1;
+ return prog->sec_idx == obj->efile.text_shndx;
}
struct bpf_program *
