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| author | Andrii Nakryiko <andriin@fb.com> | 2019-08-01 00:24:05 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-09-10 10:35:10 +0100 |
| commit | b8a132a4c4b6e97c8f157623167c8d5a5b75c1ab (patch) | |
| tree | 6d0bda5719d2fa2dde87a0c6687ad0eccd93899b /tools/lib | |
| parent | a65fb2895af4a11b2ca0457926ae24c5feeaab6b (diff) | |
| download | linux-stable-b8a132a4c4b6e97c8f157623167c8d5a5b75c1ab.tar.gz linux-stable-b8a132a4c4b6e97c8f157623167c8d5a5b75c1ab.tar.bz2 linux-stable-b8a132a4c4b6e97c8f157623167c8d5a5b75c1ab.zip | |
libbpf: set BTF FD for prog only when there is supported .BTF.ext data
[ Upstream commit 3415ec643e7bd644b03026efbe2f2b36cbe9b34b ]
5d01ab7bac46 ("libbpf: fix erroneous multi-closing of BTF FD")
introduced backwards-compatibility issue, manifesting itself as -E2BIG
error returned on program load due to unknown non-zero btf_fd attribute
value for BPF_PROG_LOAD sys_bpf() sub-command.
This patch fixes bug by ensuring that we only ever associate BTF FD with
program if there is a BTF.ext data that was successfully loaded into
kernel, which automatically means kernel supports func_info/line_info
and associated BTF FD for progs (checked and ensured also by BTF
sanitization code).
Fixes: 5d01ab7bac46 ("libbpf: fix erroneous multi-closing of BTF FD")
Reported-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 21355f6be243..0ccf6aa533ae 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2071,7 +2071,11 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, load_attr.license = license; load_attr.kern_version = kern_version; load_attr.prog_ifindex = prog->prog_ifindex; - btf_fd = bpf_object__btf_fd(prog->obj); + /* if .BTF.ext was loaded, kernel supports associated BTF for prog */ + if (prog->obj->btf_ext) + btf_fd = bpf_object__btf_fd(prog->obj); + else + btf_fd = -1; load_attr.prog_btf_fd = btf_fd >= 0 ? btf_fd : 0; load_attr.func_info = prog->func_info; load_attr.func_info_rec_size = prog->func_info_rec_size; |