[PATCH 1/3] bpf: Add gpl_compatible flag to struct bpf_prog_info

From: Jiri Olsa
Date: Wed Apr 25 2018 - 13:41:22 EST


Adding gpl_compatible flag to struct bpf_prog_info
so it can be dumped via bpf_prog_get_info_by_fd and
displayed via bpftool progs dump.

Alexei noticed 4-byte hole in struct bpf_prog_info,
so we put the u32 flags field in there, and we can
keep adding bit fields in there without breaking
user space.

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
include/uapi/linux/bpf.h | 1 +
kernel/bpf/syscall.c | 1 +
2 files changed, 2 insertions(+)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index e6679393b687..da8801860c7d 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1060,6 +1060,7 @@ struct bpf_prog_info {
__aligned_u64 map_ids;
char name[BPF_OBJ_NAME_LEN];
__u32 ifindex;
+ __u32 gpl_compatible:1;
__u64 netns_dev;
__u64 netns_ino;
} __attribute__((aligned(8)));
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index fe23dc5a3ec4..7bb4ff1c770a 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1914,6 +1914,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
info.load_time = prog->aux->load_time;
info.created_by_uid = from_kuid_munged(current_user_ns(),
prog->aux->user->uid);
+ info.gpl_compatible = prog->gpl_compatible;

memcpy(info.tag, prog->tag, sizeof(prog->tag));
memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
--
2.13.6