| Message ID | 20181212173747.3354304-1-songliubraving@fb.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [v3,bpf-next,1/2] bpf: include sub program tags in bpf_prog_info | expand |
On Wed, Dec 12, 2018 at 09:37:46AM -0800, Song Liu wrote: > Changes v2 -> v3: > 1. remove check for bpf_dump_raw_ok(). > > Changes v1 -> v2: > 1. Fix error path as Martin suggested. > > This patch adds nr_prog_tags and prog_tags to bpf_prog_info. This is a > reliable way for user space to get tags of all sub programs. Before this > patch, user space need to find sub program tags via kallsyms. Acked-by: Martin KaFai Lau <kafai@fb.com>
On 12/12/2018 06:37 PM, Song Liu wrote: > Changes v2 -> v3: > 1. remove check for bpf_dump_raw_ok(). > > Changes v1 -> v2: > 1. Fix error path as Martin suggested. > > This patch adds nr_prog_tags and prog_tags to bpf_prog_info. This is a > reliable way for user space to get tags of all sub programs. Before this > patch, user space need to find sub program tags via kallsyms. > > This feature will be used in BPF introspection, where user space queries > information about BPF programs via sys_bpf. > > Signed-off-by: Song Liu <songliubraving@fb.com> Looks better, applied, thanks!
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index aa582cd5bfcf..e7d57e89f25f 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -2717,6 +2717,8 @@ struct bpf_prog_info { __u32 nr_jited_line_info; __u32 line_info_rec_size; __u32 jited_line_info_rec_size; + __u32 nr_prog_tags; + __aligned_u64 prog_tags; } __attribute__((aligned(8))); struct bpf_map_info { diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 70fb11106fc2..894a2199ec40 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2323,6 +2323,28 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, } } + ulen = info.nr_prog_tags; + info.nr_prog_tags = prog->aux->func_cnt ? : 1; + if (ulen) { + __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; + u32 i; + + user_prog_tags = u64_to_user_ptr(info.prog_tags); + ulen = min_t(u32, info.nr_prog_tags, ulen); + if (prog->aux->func_cnt) { + for (i = 0; i < ulen; i++) { + if (copy_to_user(user_prog_tags[i], + prog->aux->func[i]->tag, + BPF_TAG_SIZE)) + return -EFAULT; + } + } else { + if (copy_to_user(user_prog_tags[0], + prog->tag, BPF_TAG_SIZE)) + return -EFAULT; + } + } + done: if (copy_to_user(uinfo, &info, info_len) || put_user(info_len, &uattr->info.info_len))
Changes v2 -> v3: 1. remove check for bpf_dump_raw_ok(). Changes v1 -> v2: 1. Fix error path as Martin suggested. This patch adds nr_prog_tags and prog_tags to bpf_prog_info. This is a reliable way for user space to get tags of all sub programs. Before this patch, user space need to find sub program tags via kallsyms. This feature will be used in BPF introspection, where user space queries information about BPF programs via sys_bpf. Signed-off-by: Song Liu <songliubraving@fb.com> --- include/uapi/linux/bpf.h | 2 ++ kernel/bpf/syscall.c | 22 ++++++++++++++++++++++ 2 files changed, 24 insertions(+) -- 2.17.1