From 6792c0b562527494acd756e8f877d248aeaec7e5 Mon Sep 17 00:00:00 2001 From: Xu Kuohai Date: Tue, 1 Mar 2022 00:32:49 -0500 Subject: libbpf: Skip forward declaration when counting duplicated type names [ Upstream commit 4226961b0019b2e1612029e8950a9e911affc995 ] Currently if a declaration appears in the BTF before the definition, the definition is dumped as a conflicting name, e.g.: $ bpftool btf dump file vmlinux format raw | grep "'unix_sock'" [81287] FWD 'unix_sock' fwd_kind=struct [89336] STRUCT 'unix_sock' size=1024 vlen=14 $ bpftool btf dump file vmlinux format c | grep "struct unix_sock" struct unix_sock; struct unix_sock___2 { <--- conflict, the "___2" is unexpected struct unix_sock___2 *unix_sk; This causes a compilation error if the dump output is used as a header file. Fix it by skipping declaration when counting duplicated type names. Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion") Signed-off-by: Xu Kuohai Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20220301053250.1464204-2-xukuohai@huawei.com Signed-off-by: Sasha Levin --- tools/lib/bpf/btf_dump.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'tools') diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index 463447a071d6..841cc68e3f42 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -1481,6 +1481,11 @@ static const char *btf_dump_resolve_name(struct btf_dump *d, __u32 id, if (s->name_resolved) return *cached_name ? *cached_name : orig_name; + if (btf_is_fwd(t) || (btf_is_enum(t) && btf_vlen(t) == 0)) { + s->name_resolved = 1; + return orig_name; + } + dup_cnt = btf_dump_name_dups(d, name_map, orig_name); if (dup_cnt > 1) { const size_t max_len = 256; -- cgit v1.2.3