[PATCH 1/3] bpf: Store license string for loaded program

Jiri Olsa
2018-04-23T07:00:36Z

Storing the license string provided loaded program,
so it can be provided back when dumping the loaded
programs info (added in following change).

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 1 +
include/uapi/linux/bpf.h | 3 +++
kernel/bpf/core.c | 1 +
kernel/bpf/syscall.c | 7 ++++++-
4 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index ee5275e7d4df..8530b791c1b0 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -274,6 +274,7 @@ struct bpf_prog_aux {
struct user_struct *user;
u64 load_time; /* ns since boottime */
char name[BPF_OBJ_NAME_LEN];
+ char *license;
#ifdef CONFIG_SECURITY
void *security;
#endif
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index c8383a289f7b..b7298ee177e7 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -239,6 +239,8 @@ enum bpf_attach_type {

#define BPF_OBJ_NAME_LEN 16U

+#define BPF_OBJ_LICENSE_LEN 128U
+
/* Flags for accessing BPF object */
#define BPF_F_RDONLY (1U << 3)
#define BPF_F_WRONLY (1U << 4)
@@ -1039,6 +1041,7 @@ struct bpf_prog_info {
__u32 ifindex;
__u64 netns_dev;
__u64 netns_ino;
+ char license[BPF_OBJ_LICENSE_LEN];
} __attribute__((aligned(8)));

struct bpf_map_info {
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index d315b393abdd..05352a928917 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -142,6 +142,7 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,

void __bpf_prog_free(struct bpf_prog *fp)
{
+ kfree(fp->aux->license);
kfree(fp->aux);
vfree(fp);
}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index fe23dc5a3ec4..a876af93147f 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1265,7 +1265,7 @@ static int bpf_prog_load(union bpf_attr *attr)
enum bpf_prog_type type = attr->prog_type;
struct bpf_prog *prog;
int err;
- char license[128];
+ char license[BPF_OBJ_LICENSE_LEN];
bool is_gpl;

if (CHECK_ATTR(BPF_PROG_LOAD))
@@ -1345,6 +1345,10 @@ static int bpf_prog_load(union bpf_attr *attr)
if (err)
goto free_prog;

+ prog->aux->license = kstrdup(license, GFP_KERNEL);
+ if (!prog->aux->license)
+ goto free_prog;
+
/* run eBPF verifier */
err = bpf_check(&prog, attr);
if (err < 0)
@@ -1917,6 +1921,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,

memcpy(info.tag, prog->tag, sizeof(prog->tag));
memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
+ strncpy(info.license, prog->aux->license, BPF_OBJ_LICENSE_LEN);

ulen = info.nr_map_ids;
info.nr_map_ids = prog->aux->used_map_cnt;
--
2.13.6