| Message ID | 20181121192242.1802994-1-yhs@fb.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [bpf-next] bpf: fix a libbpf loader issue | expand |
On Wed, Nov 21, 2018 at 11:22:42AM -0800, Yonghong Song wrote: > Commit 2993e0515bb4 ("tools/bpf: add support to read .BTF.ext sections") > added support to read .BTF.ext sections from an object file, create > and pass prog_btf_fd and func_info to the kernel. > > The program btf_fd (prog->btf_fd) is initialized to be -1 to please > zclose so we do not need special handling dur prog close. > Passing -1 to the kernel, however, will cause loading error. > Passing btf_fd 0 to the kernel if prog->btf_fd is invalid > fixed the problem. Acked-by: Martin KaFai Lau <kafai@fb.com>
On 11/21/2018 08:22 PM, Yonghong Song wrote: > Commit 2993e0515bb4 ("tools/bpf: add support to read .BTF.ext sections") > added support to read .BTF.ext sections from an object file, create > and pass prog_btf_fd and func_info to the kernel. > > The program btf_fd (prog->btf_fd) is initialized to be -1 to please > zclose so we do not need special handling dur prog close. > Passing -1 to the kernel, however, will cause loading error. > Passing btf_fd 0 to the kernel if prog->btf_fd is invalid > fixed the problem. > > Fixes: 2993e0515bb4 ("tools/bpf: add support to read .BTF.ext sections") > Reported-by: Andrey Ignatov <rdna@fb.com> > Reported-by: Emre Cantimur <haydum@fb.com> > Tested-by: Andrey Ignatov <rdna@fb.com> > Signed-off-by: Yonghong Song <yhs@fb.com> Applied, thanks!
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index cb6565d79603..f022ac82e882 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1387,7 +1387,7 @@ 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; - load_attr.prog_btf_fd = prog->btf_fd; + load_attr.prog_btf_fd = prog->btf_fd >= 0 ? prog->btf_fd : 0; load_attr.func_info = prog->func_info; load_attr.func_info_rec_size = prog->func_info_rec_size; load_attr.func_info_cnt = func_info_cnt;
Commit 2993e0515bb4 ("tools/bpf: add support to read .BTF.ext sections") added support to read .BTF.ext sections from an object file, create and pass prog_btf_fd and func_info to the kernel. The program btf_fd (prog->btf_fd) is initialized to be -1 to please zclose so we do not need special handling dur prog close. Passing -1 to the kernel, however, will cause loading error. Passing btf_fd 0 to the kernel if prog->btf_fd is invalid fixed the problem. Fixes: 2993e0515bb4 ("tools/bpf: add support to read .BTF.ext sections") Reported-by: Andrey Ignatov <rdna@fb.com> Reported-by: Emre Cantimur <haydum@fb.com> Tested-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> --- tools/lib/bpf/libbpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)