From 9683e5775c75097c46bd24e65411b16ac6c6cbb3 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Tue, 4 May 2021 16:49:10 -0700 Subject: libbpf: Add NULL check to add_dummy_ksym_var Avoids a segv if btf isn't present. Seen on the call path __bpf_object__open calling bpf_object__collect_externs. Fixes: 5bd022ec01f0 (libbpf: Support extern kernel function) Suggested-by: Stanislav Fomichev Suggested-by: Petar Penkov Signed-off-by: Ian Rogers Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210504234910.976501-1-irogers@google.com --- tools/lib/bpf/libbpf.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'tools/lib') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index e2a3cf437814..c41d9b2b59ac 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -3216,6 +3216,9 @@ static int add_dummy_ksym_var(struct btf *btf) const struct btf_var_secinfo *vs; const struct btf_type *sec; + if (!btf) + return 0; + sec_btf_id = btf__find_by_name_kind(btf, KSYMS_SEC, BTF_KIND_DATASEC); if (sec_btf_id < 0) -- cgit v1.2.3 From 67e7ec0bd4535fc6e6d3f5d174f80e10a8a80c6e Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Sat, 8 May 2021 12:22:12 -0300 Subject: libbpf: Provide GELF_ST_VISIBILITY() define for older libelf Where that macro isn't available. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/YJaspEh0qZr4LYOc@kernel.org --- tools/lib/bpf/libbpf_internal.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'tools/lib') diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index ee426226928f..acbcf6c7bdf8 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -41,6 +41,11 @@ #define ELF_C_READ_MMAP ELF_C_READ #endif +/* Older libelf all end up in this expression, for both 32 and 64 bit */ +#ifndef GELF_ST_VISIBILITY +#define GELF_ST_VISIBILITY(o) ((o) & 0x03) +#endif + #define BTF_INFO_ENC(kind, kind_flag, vlen) \ ((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN)) #define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type) -- cgit v1.2.3