From: Andrii Nakryiko andriin@fb.com
[ Upstream commit d121e1d34b72c4975ff0340901d926c0aaf98174 ]
When finding target type candidates, ignore forward declarations, functions, and other named types of incompatible kind. Not doing this can cause false errors. See [0] for one such case (due to struct pt_regs forward declaration).
[0] https://github.com/iovisor/bcc/pull/2806#issuecomment-598543645
Fixes: ddc7c3042614 ("libbpf: implement BPF CO-RE offset relocation algorithm") Reported-by: Wenbo Zhang ethercflow@gmail.com Signed-off-by: Andrii Nakryiko andriin@fb.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: Martin KaFai Lau kafai@fb.com Link: https://lore.kernel.org/bpf/20200313172336.1879637-3-andriin@fb.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/lib/bpf/libbpf.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b6403712c2f4c..5f3a8b3a54ad7 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2534,6 +2534,10 @@ static struct ids_vec *bpf_core_find_cands(const struct btf *local_btf, if (str_is_empty(targ_name)) continue;
+ t = skip_mods_and_typedefs(targ_btf, i, NULL); + if (!btf_is_composite(t) && !btf_is_array(t)) + continue; + targ_essent_len = bpf_core_essential_name_len(targ_name); if (targ_essent_len != local_essent_len) continue;