From dde7b3f5f2f458297aeccfd4783e53ab8ca046db Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Sat, 13 Mar 2021 13:09:17 -0800 Subject: libbpf: Add explicit padding to bpf_xdp_set_link_opts Adding such anonymous padding fixes the issue with uninitialized portions of bpf_xdp_set_link_opts when using LIBBPF_DECLARE_OPTS macro with inline field initialization: DECLARE_LIBBPF_OPTS(bpf_xdp_set_link_opts, opts, .old_fd = -1); When such code is compiled in debug mode, compiler is generating code that leaves padding bytes uninitialized, which triggers error inside libbpf APIs that do strict zero initialization checks for OPTS structs. Adding anonymous padding field fixes the issue. Fixes: bd5ca3ef93cd ("libbpf: Add function to set link XDP fd while specifying old program") Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20210313210920.1959628-2-andrii@kernel.org --- tools/lib/bpf/libbpf.h | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/lib') diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 3c35eb401931..3d690d4e785c 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -507,6 +507,7 @@ struct xdp_link_info { struct bpf_xdp_set_link_opts { size_t sz; int old_fd; + size_t :0; }; #define bpf_xdp_set_link_opts__last_field old_fd -- cgit v1.2.3