Factor out the logic in bpf_prog_get_fd_by_id() and add
bpf_prog_get_by_id()/bpf_prog_get_type_dev_by_id().
Also export bpf_prog_get_type_dev_by_id(), which will be used by the
following commit to get bpf prog from its id.
Signed-off-by: Toshiaki Makita <toshiaki.makita1@xxxxxxxxx>
---
include/linux/bpf.h | 8 ++++++++
kernel/bpf/syscall.c | 42 ++++++++++++++++++++++++++++++++++--------
2 files changed, 42 insertions(+), 8 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 282e28b..78fe7ef 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -636,6 +636,8 @@ int bpf_prog_array_copy(struct bpf_prog_array *old_array,
struct bpf_prog *bpf_prog_get(u32 ufd);
struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
bool attach_drv);
+struct bpf_prog *bpf_prog_get_type_dev_by_id(u32 id, enum bpf_prog_type type,
+ bool attach_drv);
struct bpf_prog * __must_check bpf_prog_add(struct bpf_prog *prog, int i);
void bpf_prog_sub(struct bpf_prog *prog, int i);
struct bpf_prog * __must_check bpf_prog_inc(struct bpf_prog *prog);
@@ -760,6 +762,12 @@ static inline struct bpf_prog *bpf_prog_get_type_dev(u32 ufd,
return ERR_PTR(-EOPNOTSUPP);
}
+static inline struct bpf_prog *
+bpf_prog_get_type_dev_by_id(u32 id, enum bpf_prog_type type, bool attach_drv)
+{
+ return ERR_PTR(-EOPNOTSUPP);
+}
+
static inline struct bpf_prog * __must_check bpf_prog_add(struct bpf_prog *prog,
int i)
{
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 82eabd4..2dd6cfc 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2139,6 +2139,39 @@ static int bpf_obj_get_next_id(const union bpf_attr *attr,
return err;
}
+static struct bpf_prog *bpf_prog_get_by_id(u32 id)
+{
+ struct bpf_prog *prog;
+
+ spin_lock_bh(&prog_idr_lock);
+ prog = idr_find(&prog_idr, id);
+ if (prog)
+ prog = bpf_prog_inc_not_zero(prog);
+ else
+ prog = ERR_PTR(-ENOENT);
+ spin_unlock_bh(&prog_idr_lock);
+
+ return prog;
+}
+
+struct bpf_prog *bpf_prog_get_type_dev_by_id(u32 id, enum bpf_prog_type type,
+ bool attach_drv)
+{
+ struct bpf_prog *prog;
+
+ prog = bpf_prog_get_by_id(id);
+ if (IS_ERR(prog))
+ return prog;
+
+ if (!bpf_prog_get_ok(prog, &type, attach_drv)) {
+ bpf_prog_put(prog);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return prog;
+}
+EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev_by_id);
+
#define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
@@ -2153,14 +2186,7 @@ static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- spin_lock_bh(&prog_idr_lock);
- prog = idr_find(&prog_idr, id);
- if (prog)
- prog = bpf_prog_inc_not_zero(prog);
- else
- prog = ERR_PTR(-ENOENT);
- spin_unlock_bh(&prog_idr_lock);
-
+ prog = bpf_prog_get_by_id(id);
if (IS_ERR(prog))
return PTR_ERR(prog);
--
1.8.3.1
