From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753429AbbJPBJd (ORCPT ); Thu, 15 Oct 2015 21:09:33 -0400 Received: from www62.your-server.de ([213.133.104.62]:58411 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752263AbbJPBJa (ORCPT ); Thu, 15 Oct 2015 21:09:30 -0400 From: Daniel Borkmann To: davem@davemloft.net Cc: ast@plumgrid.com, viro@ZenIV.linux.org.uk, ebiederm@xmission.com, tgraf@suug.ch, hannes@stressinduktion.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Daniel Borkmann Subject: [PATCH net-next 2/4] bpf: align and clean bpf_{map,prog}_get helpers Date: Fri, 16 Oct 2015 03:09:23 +0200 Message-Id: X-Mailer: git-send-email 1.9.3 In-Reply-To: References: In-Reply-To: References: X-Authenticated-Sender: daniel@iogearbox.net Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Acked-by: Alexei Starovoitov --- include/linux/bpf.h | 2 +- kernel/bpf/syscall.c | 41 +++++++++++++++++++++++------------------ kernel/bpf/verifier.c | 3 +-- 3 files changed, 25 insertions(+), 21 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index e3a51b7..0ae6f77 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -167,7 +167,7 @@ struct bpf_prog *bpf_prog_get(u32 ufd); void bpf_prog_put(struct bpf_prog *prog); void bpf_prog_put_rcu(struct bpf_prog *prog); -struct bpf_map *bpf_map_get(struct fd f); +struct bpf_map *__bpf_map_get(struct fd f); void bpf_map_put(struct bpf_map *map); extern int sysctl_unprivileged_bpf_disabled; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 2b89ef0..3fff82c 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -162,19 +162,29 @@ free_map: /* if error is returned, fd is released. * On success caller should complete fd access with matching fdput() */ -struct bpf_map *bpf_map_get(struct fd f) +struct bpf_map *__bpf_map_get(struct fd f) { - struct bpf_map *map; - if (!f.file) return ERR_PTR(-EBADF); - if (f.file->f_op != &bpf_map_fops) { fdput(f); return ERR_PTR(-EINVAL); } - map = f.file->private_data; + return f.file->private_data; +} + +static struct bpf_map *bpf_map_get(u32 ufd) +{ + struct fd f = fdget(ufd); + struct bpf_map *map; + + map = __bpf_map_get(f); + if (IS_ERR(map)) + return map; + + atomic_inc(&map->refcnt); + fdput(f); return map; } @@ -202,7 +212,7 @@ static int map_lookup_elem(union bpf_attr *attr) return -EINVAL; f = fdget(ufd); - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); @@ -261,7 +271,7 @@ static int map_update_elem(union bpf_attr *attr) return -EINVAL; f = fdget(ufd); - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); @@ -314,7 +324,7 @@ static int map_delete_elem(union bpf_attr *attr) return -EINVAL; f = fdget(ufd); - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); @@ -355,7 +365,7 @@ static int map_get_next_key(union bpf_attr *attr) return -EINVAL; f = fdget(ufd); - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); @@ -549,21 +559,16 @@ static int bpf_prog_new_fd(struct bpf_prog *prog) O_RDWR | O_CLOEXEC); } -static struct bpf_prog *get_prog(struct fd f) +static struct bpf_prog *__bpf_prog_get(struct fd f) { - struct bpf_prog *prog; - if (!f.file) return ERR_PTR(-EBADF); - if (f.file->f_op != &bpf_prog_fops) { fdput(f); return ERR_PTR(-EINVAL); } - prog = f.file->private_data; - - return prog; + return f.file->private_data; } /* called by sockets/tracing/seccomp before attaching program to an event @@ -574,13 +579,13 @@ struct bpf_prog *bpf_prog_get(u32 ufd) struct fd f = fdget(ufd); struct bpf_prog *prog; - prog = get_prog(f); - + prog = __bpf_prog_get(f); if (IS_ERR(prog)) return prog; atomic_inc(&prog->aux->refcnt); fdput(f); + return prog; } EXPORT_SYMBOL_GPL(bpf_prog_get); diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 1d6b97b..735999a 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1988,8 +1988,7 @@ 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); -- 1.9.3