bpf: align and clean bpf_{map,prog}_get helpers

Add a bpf_map_get() function that we're going to use later on and
align/clean the remaining helpers a bit so that we have them a bit
more consistent:

  - __bpf_map_get() and __bpf_prog_get() that both work on the fd
    struct, check whether the descriptor is eBPF and return the
    pointer to the map/prog stored in the private data.

    Also, we can return f.file->private_data directly, the function
    signature is enough of a documentation already.

  - bpf_map_get() and bpf_prog_get() that both work on u32 user fd,
    call their respective __bpf_map_get()/__bpf_prog_get() variants,
    and take a reference.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 2 deletions

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index b56cf51f8d42..fdc88c5a60e3 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1989,8 +1989,7 @@ static int replace_map_fd_with_map_ptr(struct verifier_env *env)
 			}
 
 			f = fdget(insn->imm);
-
-			map = bpf_map_get(f);
+			map = __bpf_map_get(f);
 			if (IS_ERR(map)) {
 				verbose("fd %d is not pointing to valid bpf_map\n",
 					insn->imm);