forked from luck/tmp_suning_uos_patched
5dc4c4b7d4
This patch introduces a new map type BPF_MAP_TYPE_REUSEPORT_SOCKARRAY. To unleash the full potential of a bpf prog, it is essential for the userspace to be capable of directly setting up a bpf map which can then be consumed by the bpf prog to make decision. In this case, decide which SO_REUSEPORT sk to serve the incoming request. By adding BPF_MAP_TYPE_REUSEPORT_SOCKARRAY, the userspace has total control and visibility on where a SO_REUSEPORT sk should be located in a bpf map. The later patch will introduce BPF_PROG_TYPE_SK_REUSEPORT such that the bpf prog can directly select a sk from the bpf map. That will raise the programmability of the bpf prog attached to a reuseport group (a group of sk serving the same IP:PORT). For example, in UDP, the bpf prog can peek into the payload (e.g. through the "data" pointer introduced in the later patch) to learn the application level's connection information and then decide which sk to pick from a bpf map. The userspace can tightly couple the sk's location in a bpf map with the application logic in generating the UDP payload's connection information. This connection info contact/API stays within the userspace. Also, when used with map-in-map, the userspace can switch the old-server-process's inner map to a new-server-process's inner map in one call "bpf_map_update_elem(outer_map, &index, &new_reuseport_array)". The bpf prog will then direct incoming requests to the new process instead of the old process. The old process can finish draining the pending requests (e.g. by "accept()") before closing the old-fds. [Note that deleting a fd from a bpf map does not necessary mean the fd is closed] During map_update_elem(), Only SO_REUSEPORT sk (i.e. which has already been added to a reuse->socks[]) can be used. That means a SO_REUSEPORT sk that is "bind()" for UDP or "bind()+listen()" for TCP. These conditions are ensured in "reuseport_array_update_check()". A SO_REUSEPORT sk can only be added once to a map (i.e. the same sk cannot be added twice even to the same map). SO_REUSEPORT already allows another sk to be created for the same IP:PORT. There is no need to re-create a similar usage in the BPF side. When a SO_REUSEPORT is deleted from the "reuse->socks[]" (e.g. "close()"), it will notify the bpf map to remove it from the map also. It is done through "bpf_sk_reuseport_detach()" and it will only be called if >=1 of the "reuse->sock[]" has ever been added to a bpf map. The map_update()/map_delete() has to be in-sync with the "reuse->socks[]". Hence, the same "reuseport_lock" used by "reuse->socks[]" has to be used here also. Care has been taken to ensure the lock is only acquired when the adding sk passes some strict tests. and freeing the map does not require the reuseport_lock. The reuseport_array will also support lookup from the syscall side. It will return a sock_gen_cookie(). The sock_gen_cookie() is on-demand (i.e. a sk's cookie is not generated until the very first map_lookup_elem()). The lookup cookie is 64bits but it goes against the logical userspace expectation on 32bits sizeof(fd) (and as other fd based bpf maps do also). It may catch user in surprise if we enforce value_size=8 while userspace still pass a 32bits fd during update. Supporting different value_size between lookup and update seems unintuitive also. We also need to consider what if other existing fd based maps want to return 64bits value from syscall's lookup in the future. Hence, reuseport_array supports both value_size 4 and 8, and assuming user will usually use value_size=4. The syscall's lookup will return ENOSPC on value_size=4. It will will only return 64bits value from sock_gen_cookie() when user consciously choose value_size=8 (as a signal that lookup is desired) which then requires a 64bits value in both lookup and update. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2400 lines
55 KiB
C
2400 lines
55 KiB
C
/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of version 2 of the GNU General Public
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* License as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*/
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#include <linux/bpf.h>
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#include <linux/bpf_trace.h>
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#include <linux/bpf_lirc.h>
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#include <linux/btf.h>
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#include <linux/syscalls.h>
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#include <linux/slab.h>
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#include <linux/sched/signal.h>
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#include <linux/vmalloc.h>
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#include <linux/mmzone.h>
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#include <linux/anon_inodes.h>
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#include <linux/fdtable.h>
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#include <linux/file.h>
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#include <linux/fs.h>
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#include <linux/license.h>
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#include <linux/filter.h>
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#include <linux/version.h>
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#include <linux/kernel.h>
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#include <linux/idr.h>
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#include <linux/cred.h>
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#include <linux/timekeeping.h>
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#include <linux/ctype.h>
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#include <linux/btf.h>
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#include <linux/nospec.h>
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#define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \
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(map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
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(map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
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(map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
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#define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
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#define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map))
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#define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY)
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DEFINE_PER_CPU(int, bpf_prog_active);
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static DEFINE_IDR(prog_idr);
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static DEFINE_SPINLOCK(prog_idr_lock);
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static DEFINE_IDR(map_idr);
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static DEFINE_SPINLOCK(map_idr_lock);
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int sysctl_unprivileged_bpf_disabled __read_mostly;
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static const struct bpf_map_ops * const bpf_map_types[] = {
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#define BPF_PROG_TYPE(_id, _ops)
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#define BPF_MAP_TYPE(_id, _ops) \
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[_id] = &_ops,
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#include <linux/bpf_types.h>
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#undef BPF_PROG_TYPE
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#undef BPF_MAP_TYPE
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};
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/*
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* If we're handed a bigger struct than we know of, ensure all the unknown bits
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* are 0 - i.e. new user-space does not rely on any kernel feature extensions
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* we don't know about yet.
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*
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* There is a ToCToU between this function call and the following
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* copy_from_user() call. However, this is not a concern since this function is
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* meant to be a future-proofing of bits.
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*/
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int bpf_check_uarg_tail_zero(void __user *uaddr,
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size_t expected_size,
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size_t actual_size)
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{
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unsigned char __user *addr;
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unsigned char __user *end;
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unsigned char val;
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int err;
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if (unlikely(actual_size > PAGE_SIZE)) /* silly large */
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return -E2BIG;
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if (unlikely(!access_ok(VERIFY_READ, uaddr, actual_size)))
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return -EFAULT;
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if (actual_size <= expected_size)
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return 0;
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addr = uaddr + expected_size;
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end = uaddr + actual_size;
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for (; addr < end; addr++) {
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err = get_user(val, addr);
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if (err)
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return err;
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if (val)
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return -E2BIG;
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}
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return 0;
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}
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const struct bpf_map_ops bpf_map_offload_ops = {
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.map_alloc = bpf_map_offload_map_alloc,
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.map_free = bpf_map_offload_map_free,
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};
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static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
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{
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const struct bpf_map_ops *ops;
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u32 type = attr->map_type;
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struct bpf_map *map;
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int err;
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if (type >= ARRAY_SIZE(bpf_map_types))
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return ERR_PTR(-EINVAL);
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type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
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ops = bpf_map_types[type];
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if (!ops)
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return ERR_PTR(-EINVAL);
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if (ops->map_alloc_check) {
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err = ops->map_alloc_check(attr);
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if (err)
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return ERR_PTR(err);
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}
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if (attr->map_ifindex)
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ops = &bpf_map_offload_ops;
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map = ops->map_alloc(attr);
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if (IS_ERR(map))
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return map;
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map->ops = ops;
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map->map_type = type;
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return map;
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}
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void *bpf_map_area_alloc(size_t size, int numa_node)
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{
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/* We definitely need __GFP_NORETRY, so OOM killer doesn't
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* trigger under memory pressure as we really just want to
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* fail instead.
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*/
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const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO;
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void *area;
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if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
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area = kmalloc_node(size, GFP_USER | flags, numa_node);
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if (area != NULL)
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return area;
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}
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return __vmalloc_node_flags_caller(size, numa_node, GFP_KERNEL | flags,
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__builtin_return_address(0));
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}
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void bpf_map_area_free(void *area)
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{
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kvfree(area);
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}
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void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
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{
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map->map_type = attr->map_type;
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map->key_size = attr->key_size;
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map->value_size = attr->value_size;
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map->max_entries = attr->max_entries;
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map->map_flags = attr->map_flags;
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map->numa_node = bpf_map_attr_numa_node(attr);
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}
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int bpf_map_precharge_memlock(u32 pages)
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{
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struct user_struct *user = get_current_user();
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unsigned long memlock_limit, cur;
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memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
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cur = atomic_long_read(&user->locked_vm);
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free_uid(user);
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if (cur + pages > memlock_limit)
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return -EPERM;
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return 0;
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}
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static int bpf_charge_memlock(struct user_struct *user, u32 pages)
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{
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unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
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if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
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atomic_long_sub(pages, &user->locked_vm);
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return -EPERM;
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}
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return 0;
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}
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static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
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{
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atomic_long_sub(pages, &user->locked_vm);
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}
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static int bpf_map_init_memlock(struct bpf_map *map)
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{
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struct user_struct *user = get_current_user();
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int ret;
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ret = bpf_charge_memlock(user, map->pages);
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if (ret) {
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free_uid(user);
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return ret;
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}
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map->user = user;
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return ret;
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}
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static void bpf_map_release_memlock(struct bpf_map *map)
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{
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struct user_struct *user = map->user;
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bpf_uncharge_memlock(user, map->pages);
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free_uid(user);
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}
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int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
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{
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int ret;
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ret = bpf_charge_memlock(map->user, pages);
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if (ret)
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return ret;
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map->pages += pages;
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return ret;
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}
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void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
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{
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bpf_uncharge_memlock(map->user, pages);
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map->pages -= pages;
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}
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static int bpf_map_alloc_id(struct bpf_map *map)
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{
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int id;
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idr_preload(GFP_KERNEL);
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spin_lock_bh(&map_idr_lock);
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id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
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if (id > 0)
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map->id = id;
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spin_unlock_bh(&map_idr_lock);
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idr_preload_end();
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if (WARN_ON_ONCE(!id))
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return -ENOSPC;
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return id > 0 ? 0 : id;
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}
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void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
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{
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unsigned long flags;
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/* Offloaded maps are removed from the IDR store when their device
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* disappears - even if someone holds an fd to them they are unusable,
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* the memory is gone, all ops will fail; they are simply waiting for
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* refcnt to drop to be freed.
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*/
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if (!map->id)
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return;
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if (do_idr_lock)
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spin_lock_irqsave(&map_idr_lock, flags);
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else
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__acquire(&map_idr_lock);
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idr_remove(&map_idr, map->id);
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map->id = 0;
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if (do_idr_lock)
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spin_unlock_irqrestore(&map_idr_lock, flags);
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else
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__release(&map_idr_lock);
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}
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/* called from workqueue */
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static void bpf_map_free_deferred(struct work_struct *work)
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{
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struct bpf_map *map = container_of(work, struct bpf_map, work);
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bpf_map_release_memlock(map);
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security_bpf_map_free(map);
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/* implementation dependent freeing */
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map->ops->map_free(map);
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}
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static void bpf_map_put_uref(struct bpf_map *map)
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{
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if (atomic_dec_and_test(&map->usercnt)) {
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if (map->ops->map_release_uref)
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map->ops->map_release_uref(map);
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}
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}
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/* decrement map refcnt and schedule it for freeing via workqueue
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* (unrelying map implementation ops->map_free() might sleep)
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*/
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static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
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{
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if (atomic_dec_and_test(&map->refcnt)) {
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/* bpf_map_free_id() must be called first */
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bpf_map_free_id(map, do_idr_lock);
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btf_put(map->btf);
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INIT_WORK(&map->work, bpf_map_free_deferred);
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schedule_work(&map->work);
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}
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}
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void bpf_map_put(struct bpf_map *map)
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{
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__bpf_map_put(map, true);
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}
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EXPORT_SYMBOL_GPL(bpf_map_put);
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void bpf_map_put_with_uref(struct bpf_map *map)
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{
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bpf_map_put_uref(map);
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bpf_map_put(map);
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}
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static int bpf_map_release(struct inode *inode, struct file *filp)
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{
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struct bpf_map *map = filp->private_data;
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if (map->ops->map_release)
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map->ops->map_release(map, filp);
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bpf_map_put_with_uref(map);
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return 0;
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}
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#ifdef CONFIG_PROC_FS
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static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
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{
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const struct bpf_map *map = filp->private_data;
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const struct bpf_array *array;
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u32 owner_prog_type = 0;
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u32 owner_jited = 0;
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if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
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array = container_of(map, struct bpf_array, map);
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owner_prog_type = array->owner_prog_type;
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owner_jited = array->owner_jited;
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}
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seq_printf(m,
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"map_type:\t%u\n"
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"key_size:\t%u\n"
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"value_size:\t%u\n"
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"max_entries:\t%u\n"
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"map_flags:\t%#x\n"
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"memlock:\t%llu\n"
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"map_id:\t%u\n",
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map->map_type,
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map->key_size,
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map->value_size,
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map->max_entries,
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map->map_flags,
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map->pages * 1ULL << PAGE_SHIFT,
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map->id);
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if (owner_prog_type) {
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seq_printf(m, "owner_prog_type:\t%u\n",
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owner_prog_type);
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seq_printf(m, "owner_jited:\t%u\n",
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owner_jited);
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}
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}
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#endif
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static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
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loff_t *ppos)
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{
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/* We need this handler such that alloc_file() enables
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* f_mode with FMODE_CAN_READ.
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*/
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return -EINVAL;
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}
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static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
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size_t siz, loff_t *ppos)
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{
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/* We need this handler such that alloc_file() enables
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* f_mode with FMODE_CAN_WRITE.
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*/
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return -EINVAL;
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}
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const struct file_operations bpf_map_fops = {
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#ifdef CONFIG_PROC_FS
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.show_fdinfo = bpf_map_show_fdinfo,
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#endif
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.release = bpf_map_release,
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.read = bpf_dummy_read,
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.write = bpf_dummy_write,
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};
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int bpf_map_new_fd(struct bpf_map *map, int flags)
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{
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int ret;
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ret = security_bpf_map(map, OPEN_FMODE(flags));
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if (ret < 0)
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return ret;
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return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
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flags | O_CLOEXEC);
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}
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int bpf_get_file_flag(int flags)
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{
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if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
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return -EINVAL;
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if (flags & BPF_F_RDONLY)
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return O_RDONLY;
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if (flags & BPF_F_WRONLY)
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return O_WRONLY;
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return O_RDWR;
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}
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/* helper macro to check that unused fields 'union bpf_attr' are zero */
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#define CHECK_ATTR(CMD) \
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memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
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sizeof(attr->CMD##_LAST_FIELD), 0, \
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sizeof(*attr) - \
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offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
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sizeof(attr->CMD##_LAST_FIELD)) != NULL
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/* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
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* Return 0 on success and < 0 on error.
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*/
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static int bpf_obj_name_cpy(char *dst, const char *src)
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{
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const char *end = src + BPF_OBJ_NAME_LEN;
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|
|
|
memset(dst, 0, BPF_OBJ_NAME_LEN);
|
|
|
|
/* Copy all isalnum() and '_' char */
|
|
while (src < end && *src) {
|
|
if (!isalnum(*src) && *src != '_')
|
|
return -EINVAL;
|
|
*dst++ = *src++;
|
|
}
|
|
|
|
/* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
|
|
if (src == end)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id
|
|
/* called via syscall */
|
|
static int map_create(union bpf_attr *attr)
|
|
{
|
|
int numa_node = bpf_map_attr_numa_node(attr);
|
|
struct bpf_map *map;
|
|
int f_flags;
|
|
int err;
|
|
|
|
err = CHECK_ATTR(BPF_MAP_CREATE);
|
|
if (err)
|
|
return -EINVAL;
|
|
|
|
f_flags = bpf_get_file_flag(attr->map_flags);
|
|
if (f_flags < 0)
|
|
return f_flags;
|
|
|
|
if (numa_node != NUMA_NO_NODE &&
|
|
((unsigned int)numa_node >= nr_node_ids ||
|
|
!node_online(numa_node)))
|
|
return -EINVAL;
|
|
|
|
/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
|
|
map = find_and_alloc_map(attr);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
err = bpf_obj_name_cpy(map->name, attr->map_name);
|
|
if (err)
|
|
goto free_map_nouncharge;
|
|
|
|
atomic_set(&map->refcnt, 1);
|
|
atomic_set(&map->usercnt, 1);
|
|
|
|
if (bpf_map_support_seq_show(map) &&
|
|
(attr->btf_key_type_id || attr->btf_value_type_id)) {
|
|
struct btf *btf;
|
|
|
|
if (!attr->btf_key_type_id || !attr->btf_value_type_id) {
|
|
err = -EINVAL;
|
|
goto free_map_nouncharge;
|
|
}
|
|
|
|
btf = btf_get_by_fd(attr->btf_fd);
|
|
if (IS_ERR(btf)) {
|
|
err = PTR_ERR(btf);
|
|
goto free_map_nouncharge;
|
|
}
|
|
|
|
err = map->ops->map_check_btf(map, btf, attr->btf_key_type_id,
|
|
attr->btf_value_type_id);
|
|
if (err) {
|
|
btf_put(btf);
|
|
goto free_map_nouncharge;
|
|
}
|
|
|
|
map->btf = btf;
|
|
map->btf_key_type_id = attr->btf_key_type_id;
|
|
map->btf_value_type_id = attr->btf_value_type_id;
|
|
}
|
|
|
|
err = security_bpf_map_alloc(map);
|
|
if (err)
|
|
goto free_map_nouncharge;
|
|
|
|
err = bpf_map_init_memlock(map);
|
|
if (err)
|
|
goto free_map_sec;
|
|
|
|
err = bpf_map_alloc_id(map);
|
|
if (err)
|
|
goto free_map;
|
|
|
|
err = bpf_map_new_fd(map, f_flags);
|
|
if (err < 0) {
|
|
/* failed to allocate fd.
|
|
* bpf_map_put() is needed because the above
|
|
* bpf_map_alloc_id() has published the map
|
|
* to the userspace and the userspace may
|
|
* have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
|
|
*/
|
|
bpf_map_put(map);
|
|
return err;
|
|
}
|
|
|
|
return err;
|
|
|
|
free_map:
|
|
bpf_map_release_memlock(map);
|
|
free_map_sec:
|
|
security_bpf_map_free(map);
|
|
free_map_nouncharge:
|
|
btf_put(map->btf);
|
|
map->ops->map_free(map);
|
|
return err;
|
|
}
|
|
|
|
/* 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)
|
|
{
|
|
if (!f.file)
|
|
return ERR_PTR(-EBADF);
|
|
if (f.file->f_op != &bpf_map_fops) {
|
|
fdput(f);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
return f.file->private_data;
|
|
}
|
|
|
|
/* prog's and map's refcnt limit */
|
|
#define BPF_MAX_REFCNT 32768
|
|
|
|
struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
|
|
{
|
|
if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
|
|
atomic_dec(&map->refcnt);
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
if (uref)
|
|
atomic_inc(&map->usercnt);
|
|
return map;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_map_inc);
|
|
|
|
struct bpf_map *bpf_map_get_with_uref(u32 ufd)
|
|
{
|
|
struct fd f = fdget(ufd);
|
|
struct bpf_map *map;
|
|
|
|
map = __bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return map;
|
|
|
|
map = bpf_map_inc(map, true);
|
|
fdput(f);
|
|
|
|
return map;
|
|
}
|
|
|
|
/* map_idr_lock should have been held */
|
|
static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map,
|
|
bool uref)
|
|
{
|
|
int refold;
|
|
|
|
refold = __atomic_add_unless(&map->refcnt, 1, 0);
|
|
|
|
if (refold >= BPF_MAX_REFCNT) {
|
|
__bpf_map_put(map, false);
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
|
|
if (!refold)
|
|
return ERR_PTR(-ENOENT);
|
|
|
|
if (uref)
|
|
atomic_inc(&map->usercnt);
|
|
|
|
return map;
|
|
}
|
|
|
|
int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
|
|
{
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
/* last field in 'union bpf_attr' used by this command */
|
|
#define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value
|
|
|
|
static int map_lookup_elem(union bpf_attr *attr)
|
|
{
|
|
void __user *ukey = u64_to_user_ptr(attr->key);
|
|
void __user *uvalue = u64_to_user_ptr(attr->value);
|
|
int ufd = attr->map_fd;
|
|
struct bpf_map *map;
|
|
void *key, *value, *ptr;
|
|
u32 value_size;
|
|
struct fd f;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
|
|
return -EINVAL;
|
|
|
|
f = fdget(ufd);
|
|
map = __bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
if (!(f.file->f_mode & FMODE_CAN_READ)) {
|
|
err = -EPERM;
|
|
goto err_put;
|
|
}
|
|
|
|
key = memdup_user(ukey, map->key_size);
|
|
if (IS_ERR(key)) {
|
|
err = PTR_ERR(key);
|
|
goto err_put;
|
|
}
|
|
|
|
if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
|
map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
|
|
map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
|
|
value_size = round_up(map->value_size, 8) * num_possible_cpus();
|
|
else if (IS_FD_MAP(map))
|
|
value_size = sizeof(u32);
|
|
else
|
|
value_size = map->value_size;
|
|
|
|
err = -ENOMEM;
|
|
value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
|
|
if (!value)
|
|
goto free_key;
|
|
|
|
if (bpf_map_is_dev_bound(map)) {
|
|
err = bpf_map_offload_lookup_elem(map, key, value);
|
|
} else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
|
map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
|
|
err = bpf_percpu_hash_copy(map, key, value);
|
|
} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
|
|
err = bpf_percpu_array_copy(map, key, value);
|
|
} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
|
|
err = bpf_stackmap_copy(map, key, value);
|
|
} else if (IS_FD_ARRAY(map)) {
|
|
err = bpf_fd_array_map_lookup_elem(map, key, value);
|
|
} else if (IS_FD_HASH(map)) {
|
|
err = bpf_fd_htab_map_lookup_elem(map, key, value);
|
|
} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
|
|
err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
|
|
} else {
|
|
rcu_read_lock();
|
|
ptr = map->ops->map_lookup_elem(map, key);
|
|
if (ptr)
|
|
memcpy(value, ptr, value_size);
|
|
rcu_read_unlock();
|
|
err = ptr ? 0 : -ENOENT;
|
|
}
|
|
|
|
if (err)
|
|
goto free_value;
|
|
|
|
err = -EFAULT;
|
|
if (copy_to_user(uvalue, value, value_size) != 0)
|
|
goto free_value;
|
|
|
|
err = 0;
|
|
|
|
free_value:
|
|
kfree(value);
|
|
free_key:
|
|
kfree(key);
|
|
err_put:
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
#define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
|
|
|
|
static int map_update_elem(union bpf_attr *attr)
|
|
{
|
|
void __user *ukey = u64_to_user_ptr(attr->key);
|
|
void __user *uvalue = u64_to_user_ptr(attr->value);
|
|
int ufd = attr->map_fd;
|
|
struct bpf_map *map;
|
|
void *key, *value;
|
|
u32 value_size;
|
|
struct fd f;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
|
|
return -EINVAL;
|
|
|
|
f = fdget(ufd);
|
|
map = __bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
|
|
err = -EPERM;
|
|
goto err_put;
|
|
}
|
|
|
|
key = memdup_user(ukey, map->key_size);
|
|
if (IS_ERR(key)) {
|
|
err = PTR_ERR(key);
|
|
goto err_put;
|
|
}
|
|
|
|
if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
|
map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
|
|
map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
|
|
value_size = round_up(map->value_size, 8) * num_possible_cpus();
|
|
else
|
|
value_size = map->value_size;
|
|
|
|
err = -ENOMEM;
|
|
value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
|
|
if (!value)
|
|
goto free_key;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(value, uvalue, value_size) != 0)
|
|
goto free_value;
|
|
|
|
/* Need to create a kthread, thus must support schedule */
|
|
if (bpf_map_is_dev_bound(map)) {
|
|
err = bpf_map_offload_update_elem(map, key, value, attr->flags);
|
|
goto out;
|
|
} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
|
|
map->map_type == BPF_MAP_TYPE_SOCKHASH ||
|
|
map->map_type == BPF_MAP_TYPE_SOCKMAP) {
|
|
err = map->ops->map_update_elem(map, key, value, attr->flags);
|
|
goto out;
|
|
}
|
|
|
|
/* must increment bpf_prog_active to avoid kprobe+bpf triggering from
|
|
* inside bpf map update or delete otherwise deadlocks are possible
|
|
*/
|
|
preempt_disable();
|
|
__this_cpu_inc(bpf_prog_active);
|
|
if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
|
map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
|
|
err = bpf_percpu_hash_update(map, key, value, attr->flags);
|
|
} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
|
|
err = bpf_percpu_array_update(map, key, value, attr->flags);
|
|
} else if (IS_FD_ARRAY(map)) {
|
|
rcu_read_lock();
|
|
err = bpf_fd_array_map_update_elem(map, f.file, key, value,
|
|
attr->flags);
|
|
rcu_read_unlock();
|
|
} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
|
|
rcu_read_lock();
|
|
err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
|
|
attr->flags);
|
|
rcu_read_unlock();
|
|
} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
|
|
/* rcu_read_lock() is not needed */
|
|
err = bpf_fd_reuseport_array_update_elem(map, key, value,
|
|
attr->flags);
|
|
} else {
|
|
rcu_read_lock();
|
|
err = map->ops->map_update_elem(map, key, value, attr->flags);
|
|
rcu_read_unlock();
|
|
}
|
|
__this_cpu_dec(bpf_prog_active);
|
|
preempt_enable();
|
|
out:
|
|
free_value:
|
|
kfree(value);
|
|
free_key:
|
|
kfree(key);
|
|
err_put:
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
#define BPF_MAP_DELETE_ELEM_LAST_FIELD key
|
|
|
|
static int map_delete_elem(union bpf_attr *attr)
|
|
{
|
|
void __user *ukey = u64_to_user_ptr(attr->key);
|
|
int ufd = attr->map_fd;
|
|
struct bpf_map *map;
|
|
struct fd f;
|
|
void *key;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
|
|
return -EINVAL;
|
|
|
|
f = fdget(ufd);
|
|
map = __bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
if (!(f.file->f_mode & FMODE_CAN_WRITE)) {
|
|
err = -EPERM;
|
|
goto err_put;
|
|
}
|
|
|
|
key = memdup_user(ukey, map->key_size);
|
|
if (IS_ERR(key)) {
|
|
err = PTR_ERR(key);
|
|
goto err_put;
|
|
}
|
|
|
|
if (bpf_map_is_dev_bound(map)) {
|
|
err = bpf_map_offload_delete_elem(map, key);
|
|
goto out;
|
|
}
|
|
|
|
preempt_disable();
|
|
__this_cpu_inc(bpf_prog_active);
|
|
rcu_read_lock();
|
|
err = map->ops->map_delete_elem(map, key);
|
|
rcu_read_unlock();
|
|
__this_cpu_dec(bpf_prog_active);
|
|
preempt_enable();
|
|
out:
|
|
kfree(key);
|
|
err_put:
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
/* last field in 'union bpf_attr' used by this command */
|
|
#define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
|
|
|
|
static int map_get_next_key(union bpf_attr *attr)
|
|
{
|
|
void __user *ukey = u64_to_user_ptr(attr->key);
|
|
void __user *unext_key = u64_to_user_ptr(attr->next_key);
|
|
int ufd = attr->map_fd;
|
|
struct bpf_map *map;
|
|
void *key, *next_key;
|
|
struct fd f;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
|
|
return -EINVAL;
|
|
|
|
f = fdget(ufd);
|
|
map = __bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
if (!(f.file->f_mode & FMODE_CAN_READ)) {
|
|
err = -EPERM;
|
|
goto err_put;
|
|
}
|
|
|
|
if (ukey) {
|
|
key = memdup_user(ukey, map->key_size);
|
|
if (IS_ERR(key)) {
|
|
err = PTR_ERR(key);
|
|
goto err_put;
|
|
}
|
|
} else {
|
|
key = NULL;
|
|
}
|
|
|
|
err = -ENOMEM;
|
|
next_key = kmalloc(map->key_size, GFP_USER);
|
|
if (!next_key)
|
|
goto free_key;
|
|
|
|
if (bpf_map_is_dev_bound(map)) {
|
|
err = bpf_map_offload_get_next_key(map, key, next_key);
|
|
goto out;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
err = map->ops->map_get_next_key(map, key, next_key);
|
|
rcu_read_unlock();
|
|
out:
|
|
if (err)
|
|
goto free_next_key;
|
|
|
|
err = -EFAULT;
|
|
if (copy_to_user(unext_key, next_key, map->key_size) != 0)
|
|
goto free_next_key;
|
|
|
|
err = 0;
|
|
|
|
free_next_key:
|
|
kfree(next_key);
|
|
free_key:
|
|
kfree(key);
|
|
err_put:
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
static const struct bpf_prog_ops * const bpf_prog_types[] = {
|
|
#define BPF_PROG_TYPE(_id, _name) \
|
|
[_id] = & _name ## _prog_ops,
|
|
#define BPF_MAP_TYPE(_id, _ops)
|
|
#include <linux/bpf_types.h>
|
|
#undef BPF_PROG_TYPE
|
|
#undef BPF_MAP_TYPE
|
|
};
|
|
|
|
static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
|
|
{
|
|
const struct bpf_prog_ops *ops;
|
|
|
|
if (type >= ARRAY_SIZE(bpf_prog_types))
|
|
return -EINVAL;
|
|
type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
|
|
ops = bpf_prog_types[type];
|
|
if (!ops)
|
|
return -EINVAL;
|
|
|
|
if (!bpf_prog_is_dev_bound(prog->aux))
|
|
prog->aux->ops = ops;
|
|
else
|
|
prog->aux->ops = &bpf_offload_prog_ops;
|
|
prog->type = type;
|
|
return 0;
|
|
}
|
|
|
|
/* drop refcnt on maps used by eBPF program and free auxilary data */
|
|
static void free_used_maps(struct bpf_prog_aux *aux)
|
|
{
|
|
int i;
|
|
|
|
if (aux->cgroup_storage)
|
|
bpf_cgroup_storage_release(aux->prog, aux->cgroup_storage);
|
|
|
|
for (i = 0; i < aux->used_map_cnt; i++)
|
|
bpf_map_put(aux->used_maps[i]);
|
|
|
|
kfree(aux->used_maps);
|
|
}
|
|
|
|
int __bpf_prog_charge(struct user_struct *user, u32 pages)
|
|
{
|
|
unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
|
|
unsigned long user_bufs;
|
|
|
|
if (user) {
|
|
user_bufs = atomic_long_add_return(pages, &user->locked_vm);
|
|
if (user_bufs > memlock_limit) {
|
|
atomic_long_sub(pages, &user->locked_vm);
|
|
return -EPERM;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
|
|
{
|
|
if (user)
|
|
atomic_long_sub(pages, &user->locked_vm);
|
|
}
|
|
|
|
static int bpf_prog_charge_memlock(struct bpf_prog *prog)
|
|
{
|
|
struct user_struct *user = get_current_user();
|
|
int ret;
|
|
|
|
ret = __bpf_prog_charge(user, prog->pages);
|
|
if (ret) {
|
|
free_uid(user);
|
|
return ret;
|
|
}
|
|
|
|
prog->aux->user = user;
|
|
return 0;
|
|
}
|
|
|
|
static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
|
|
{
|
|
struct user_struct *user = prog->aux->user;
|
|
|
|
__bpf_prog_uncharge(user, prog->pages);
|
|
free_uid(user);
|
|
}
|
|
|
|
static int bpf_prog_alloc_id(struct bpf_prog *prog)
|
|
{
|
|
int id;
|
|
|
|
idr_preload(GFP_KERNEL);
|
|
spin_lock_bh(&prog_idr_lock);
|
|
id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
|
|
if (id > 0)
|
|
prog->aux->id = id;
|
|
spin_unlock_bh(&prog_idr_lock);
|
|
idr_preload_end();
|
|
|
|
/* id is in [1, INT_MAX) */
|
|
if (WARN_ON_ONCE(!id))
|
|
return -ENOSPC;
|
|
|
|
return id > 0 ? 0 : id;
|
|
}
|
|
|
|
void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
|
|
{
|
|
/* cBPF to eBPF migrations are currently not in the idr store.
|
|
* Offloaded programs are removed from the store when their device
|
|
* disappears - even if someone grabs an fd to them they are unusable,
|
|
* simply waiting for refcnt to drop to be freed.
|
|
*/
|
|
if (!prog->aux->id)
|
|
return;
|
|
|
|
if (do_idr_lock)
|
|
spin_lock_bh(&prog_idr_lock);
|
|
else
|
|
__acquire(&prog_idr_lock);
|
|
|
|
idr_remove(&prog_idr, prog->aux->id);
|
|
prog->aux->id = 0;
|
|
|
|
if (do_idr_lock)
|
|
spin_unlock_bh(&prog_idr_lock);
|
|
else
|
|
__release(&prog_idr_lock);
|
|
}
|
|
|
|
static void __bpf_prog_put_rcu(struct rcu_head *rcu)
|
|
{
|
|
struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
|
|
|
|
free_used_maps(aux);
|
|
bpf_prog_uncharge_memlock(aux->prog);
|
|
security_bpf_prog_free(aux);
|
|
bpf_prog_free(aux->prog);
|
|
}
|
|
|
|
static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
|
|
{
|
|
if (atomic_dec_and_test(&prog->aux->refcnt)) {
|
|
/* bpf_prog_free_id() must be called first */
|
|
bpf_prog_free_id(prog, do_idr_lock);
|
|
bpf_prog_kallsyms_del_all(prog);
|
|
|
|
call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
|
|
}
|
|
}
|
|
|
|
void bpf_prog_put(struct bpf_prog *prog)
|
|
{
|
|
__bpf_prog_put(prog, true);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_put);
|
|
|
|
static int bpf_prog_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct bpf_prog *prog = filp->private_data;
|
|
|
|
bpf_prog_put(prog);
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
|
|
{
|
|
const struct bpf_prog *prog = filp->private_data;
|
|
char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
|
|
|
|
bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
|
|
seq_printf(m,
|
|
"prog_type:\t%u\n"
|
|
"prog_jited:\t%u\n"
|
|
"prog_tag:\t%s\n"
|
|
"memlock:\t%llu\n"
|
|
"prog_id:\t%u\n",
|
|
prog->type,
|
|
prog->jited,
|
|
prog_tag,
|
|
prog->pages * 1ULL << PAGE_SHIFT,
|
|
prog->aux->id);
|
|
}
|
|
#endif
|
|
|
|
const struct file_operations bpf_prog_fops = {
|
|
#ifdef CONFIG_PROC_FS
|
|
.show_fdinfo = bpf_prog_show_fdinfo,
|
|
#endif
|
|
.release = bpf_prog_release,
|
|
.read = bpf_dummy_read,
|
|
.write = bpf_dummy_write,
|
|
};
|
|
|
|
int bpf_prog_new_fd(struct bpf_prog *prog)
|
|
{
|
|
int ret;
|
|
|
|
ret = security_bpf_prog(prog);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
|
|
O_RDWR | O_CLOEXEC);
|
|
}
|
|
|
|
static struct bpf_prog *____bpf_prog_get(struct fd f)
|
|
{
|
|
if (!f.file)
|
|
return ERR_PTR(-EBADF);
|
|
if (f.file->f_op != &bpf_prog_fops) {
|
|
fdput(f);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
return f.file->private_data;
|
|
}
|
|
|
|
struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
|
|
{
|
|
if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
|
|
atomic_sub(i, &prog->aux->refcnt);
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
return prog;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_add);
|
|
|
|
void bpf_prog_sub(struct bpf_prog *prog, int i)
|
|
{
|
|
/* Only to be used for undoing previous bpf_prog_add() in some
|
|
* error path. We still know that another entity in our call
|
|
* path holds a reference to the program, thus atomic_sub() can
|
|
* be safely used in such cases!
|
|
*/
|
|
WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_sub);
|
|
|
|
struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
|
|
{
|
|
return bpf_prog_add(prog, 1);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_inc);
|
|
|
|
/* prog_idr_lock should have been held */
|
|
struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
|
|
{
|
|
int refold;
|
|
|
|
refold = __atomic_add_unless(&prog->aux->refcnt, 1, 0);
|
|
|
|
if (refold >= BPF_MAX_REFCNT) {
|
|
__bpf_prog_put(prog, false);
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
|
|
if (!refold)
|
|
return ERR_PTR(-ENOENT);
|
|
|
|
return prog;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
|
|
|
|
bool bpf_prog_get_ok(struct bpf_prog *prog,
|
|
enum bpf_prog_type *attach_type, bool attach_drv)
|
|
{
|
|
/* not an attachment, just a refcount inc, always allow */
|
|
if (!attach_type)
|
|
return true;
|
|
|
|
if (prog->type != *attach_type)
|
|
return false;
|
|
if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
|
|
bool attach_drv)
|
|
{
|
|
struct fd f = fdget(ufd);
|
|
struct bpf_prog *prog;
|
|
|
|
prog = ____bpf_prog_get(f);
|
|
if (IS_ERR(prog))
|
|
return prog;
|
|
if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
|
|
prog = ERR_PTR(-EINVAL);
|
|
goto out;
|
|
}
|
|
|
|
prog = bpf_prog_inc(prog);
|
|
out:
|
|
fdput(f);
|
|
return prog;
|
|
}
|
|
|
|
struct bpf_prog *bpf_prog_get(u32 ufd)
|
|
{
|
|
return __bpf_prog_get(ufd, NULL, false);
|
|
}
|
|
|
|
struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
|
|
bool attach_drv)
|
|
{
|
|
return __bpf_prog_get(ufd, &type, attach_drv);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
|
|
|
|
/* Initially all BPF programs could be loaded w/o specifying
|
|
* expected_attach_type. Later for some of them specifying expected_attach_type
|
|
* at load time became required so that program could be validated properly.
|
|
* Programs of types that are allowed to be loaded both w/ and w/o (for
|
|
* backward compatibility) expected_attach_type, should have the default attach
|
|
* type assigned to expected_attach_type for the latter case, so that it can be
|
|
* validated later at attach time.
|
|
*
|
|
* bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
|
|
* prog type requires it but has some attach types that have to be backward
|
|
* compatible.
|
|
*/
|
|
static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
|
|
{
|
|
switch (attr->prog_type) {
|
|
case BPF_PROG_TYPE_CGROUP_SOCK:
|
|
/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
|
|
* exist so checking for non-zero is the way to go here.
|
|
*/
|
|
if (!attr->expected_attach_type)
|
|
attr->expected_attach_type =
|
|
BPF_CGROUP_INET_SOCK_CREATE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
static int
|
|
bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
|
|
enum bpf_attach_type expected_attach_type)
|
|
{
|
|
switch (prog_type) {
|
|
case BPF_PROG_TYPE_CGROUP_SOCK:
|
|
switch (expected_attach_type) {
|
|
case BPF_CGROUP_INET_SOCK_CREATE:
|
|
case BPF_CGROUP_INET4_POST_BIND:
|
|
case BPF_CGROUP_INET6_POST_BIND:
|
|
return 0;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
|
|
switch (expected_attach_type) {
|
|
case BPF_CGROUP_INET4_BIND:
|
|
case BPF_CGROUP_INET6_BIND:
|
|
case BPF_CGROUP_INET4_CONNECT:
|
|
case BPF_CGROUP_INET6_CONNECT:
|
|
case BPF_CGROUP_UDP4_SENDMSG:
|
|
case BPF_CGROUP_UDP6_SENDMSG:
|
|
return 0;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* last field in 'union bpf_attr' used by this command */
|
|
#define BPF_PROG_LOAD_LAST_FIELD expected_attach_type
|
|
|
|
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];
|
|
bool is_gpl;
|
|
|
|
if (CHECK_ATTR(BPF_PROG_LOAD))
|
|
return -EINVAL;
|
|
|
|
if (attr->prog_flags & ~BPF_F_STRICT_ALIGNMENT)
|
|
return -EINVAL;
|
|
|
|
/* copy eBPF program license from user space */
|
|
if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
|
|
sizeof(license) - 1) < 0)
|
|
return -EFAULT;
|
|
license[sizeof(license) - 1] = 0;
|
|
|
|
/* eBPF programs must be GPL compatible to use GPL-ed functions */
|
|
is_gpl = license_is_gpl_compatible(license);
|
|
|
|
if (attr->insn_cnt == 0 || attr->insn_cnt > BPF_MAXINSNS)
|
|
return -E2BIG;
|
|
|
|
if (type == BPF_PROG_TYPE_KPROBE &&
|
|
attr->kern_version != LINUX_VERSION_CODE)
|
|
return -EINVAL;
|
|
|
|
if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
|
|
type != BPF_PROG_TYPE_CGROUP_SKB &&
|
|
!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
bpf_prog_load_fixup_attach_type(attr);
|
|
if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
|
|
return -EINVAL;
|
|
|
|
/* plain bpf_prog allocation */
|
|
prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
|
|
if (!prog)
|
|
return -ENOMEM;
|
|
|
|
prog->expected_attach_type = attr->expected_attach_type;
|
|
|
|
prog->aux->offload_requested = !!attr->prog_ifindex;
|
|
|
|
err = security_bpf_prog_alloc(prog->aux);
|
|
if (err)
|
|
goto free_prog_nouncharge;
|
|
|
|
err = bpf_prog_charge_memlock(prog);
|
|
if (err)
|
|
goto free_prog_sec;
|
|
|
|
prog->len = attr->insn_cnt;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
|
|
bpf_prog_insn_size(prog)) != 0)
|
|
goto free_prog;
|
|
|
|
prog->orig_prog = NULL;
|
|
prog->jited = 0;
|
|
|
|
atomic_set(&prog->aux->refcnt, 1);
|
|
prog->gpl_compatible = is_gpl ? 1 : 0;
|
|
|
|
if (bpf_prog_is_dev_bound(prog->aux)) {
|
|
err = bpf_prog_offload_init(prog, attr);
|
|
if (err)
|
|
goto free_prog;
|
|
}
|
|
|
|
/* find program type: socket_filter vs tracing_filter */
|
|
err = find_prog_type(type, prog);
|
|
if (err < 0)
|
|
goto free_prog;
|
|
|
|
prog->aux->load_time = ktime_get_boot_ns();
|
|
err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
|
|
if (err)
|
|
goto free_prog;
|
|
|
|
/* run eBPF verifier */
|
|
err = bpf_check(&prog, attr);
|
|
if (err < 0)
|
|
goto free_used_maps;
|
|
|
|
prog = bpf_prog_select_runtime(prog, &err);
|
|
if (err < 0)
|
|
goto free_used_maps;
|
|
|
|
err = bpf_prog_alloc_id(prog);
|
|
if (err)
|
|
goto free_used_maps;
|
|
|
|
err = bpf_prog_new_fd(prog);
|
|
if (err < 0) {
|
|
/* failed to allocate fd.
|
|
* bpf_prog_put() is needed because the above
|
|
* bpf_prog_alloc_id() has published the prog
|
|
* to the userspace and the userspace may
|
|
* have refcnt-ed it through BPF_PROG_GET_FD_BY_ID.
|
|
*/
|
|
bpf_prog_put(prog);
|
|
return err;
|
|
}
|
|
|
|
bpf_prog_kallsyms_add(prog);
|
|
return err;
|
|
|
|
free_used_maps:
|
|
bpf_prog_kallsyms_del_subprogs(prog);
|
|
free_used_maps(prog->aux);
|
|
free_prog:
|
|
bpf_prog_uncharge_memlock(prog);
|
|
free_prog_sec:
|
|
security_bpf_prog_free(prog->aux);
|
|
free_prog_nouncharge:
|
|
bpf_prog_free(prog);
|
|
return err;
|
|
}
|
|
|
|
#define BPF_OBJ_LAST_FIELD file_flags
|
|
|
|
static int bpf_obj_pin(const union bpf_attr *attr)
|
|
{
|
|
if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
|
|
return -EINVAL;
|
|
|
|
return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
|
|
}
|
|
|
|
static int bpf_obj_get(const union bpf_attr *attr)
|
|
{
|
|
if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
|
|
attr->file_flags & ~BPF_OBJ_FLAG_MASK)
|
|
return -EINVAL;
|
|
|
|
return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
|
|
attr->file_flags);
|
|
}
|
|
|
|
struct bpf_raw_tracepoint {
|
|
struct bpf_raw_event_map *btp;
|
|
struct bpf_prog *prog;
|
|
};
|
|
|
|
static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct bpf_raw_tracepoint *raw_tp = filp->private_data;
|
|
|
|
if (raw_tp->prog) {
|
|
bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
|
|
bpf_prog_put(raw_tp->prog);
|
|
}
|
|
kfree(raw_tp);
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations bpf_raw_tp_fops = {
|
|
.release = bpf_raw_tracepoint_release,
|
|
.read = bpf_dummy_read,
|
|
.write = bpf_dummy_write,
|
|
};
|
|
|
|
#define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
|
|
|
|
static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
|
|
{
|
|
struct bpf_raw_tracepoint *raw_tp;
|
|
struct bpf_raw_event_map *btp;
|
|
struct bpf_prog *prog;
|
|
char tp_name[128];
|
|
int tp_fd, err;
|
|
|
|
if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
|
|
sizeof(tp_name) - 1) < 0)
|
|
return -EFAULT;
|
|
tp_name[sizeof(tp_name) - 1] = 0;
|
|
|
|
btp = bpf_find_raw_tracepoint(tp_name);
|
|
if (!btp)
|
|
return -ENOENT;
|
|
|
|
raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
|
|
if (!raw_tp)
|
|
return -ENOMEM;
|
|
raw_tp->btp = btp;
|
|
|
|
prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd,
|
|
BPF_PROG_TYPE_RAW_TRACEPOINT);
|
|
if (IS_ERR(prog)) {
|
|
err = PTR_ERR(prog);
|
|
goto out_free_tp;
|
|
}
|
|
|
|
err = bpf_probe_register(raw_tp->btp, prog);
|
|
if (err)
|
|
goto out_put_prog;
|
|
|
|
raw_tp->prog = prog;
|
|
tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
|
|
O_CLOEXEC);
|
|
if (tp_fd < 0) {
|
|
bpf_probe_unregister(raw_tp->btp, prog);
|
|
err = tp_fd;
|
|
goto out_put_prog;
|
|
}
|
|
return tp_fd;
|
|
|
|
out_put_prog:
|
|
bpf_prog_put(prog);
|
|
out_free_tp:
|
|
kfree(raw_tp);
|
|
return err;
|
|
}
|
|
|
|
static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
|
|
enum bpf_attach_type attach_type)
|
|
{
|
|
switch (prog->type) {
|
|
case BPF_PROG_TYPE_CGROUP_SOCK:
|
|
case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
|
|
return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
#define BPF_PROG_ATTACH_LAST_FIELD attach_flags
|
|
|
|
#define BPF_F_ATTACH_MASK \
|
|
(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
|
|
|
|
static int bpf_prog_attach(const union bpf_attr *attr)
|
|
{
|
|
enum bpf_prog_type ptype;
|
|
struct bpf_prog *prog;
|
|
int ret;
|
|
|
|
if (!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (CHECK_ATTR(BPF_PROG_ATTACH))
|
|
return -EINVAL;
|
|
|
|
if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
|
|
return -EINVAL;
|
|
|
|
switch (attr->attach_type) {
|
|
case BPF_CGROUP_INET_INGRESS:
|
|
case BPF_CGROUP_INET_EGRESS:
|
|
ptype = BPF_PROG_TYPE_CGROUP_SKB;
|
|
break;
|
|
case BPF_CGROUP_INET_SOCK_CREATE:
|
|
case BPF_CGROUP_INET4_POST_BIND:
|
|
case BPF_CGROUP_INET6_POST_BIND:
|
|
ptype = BPF_PROG_TYPE_CGROUP_SOCK;
|
|
break;
|
|
case BPF_CGROUP_INET4_BIND:
|
|
case BPF_CGROUP_INET6_BIND:
|
|
case BPF_CGROUP_INET4_CONNECT:
|
|
case BPF_CGROUP_INET6_CONNECT:
|
|
case BPF_CGROUP_UDP4_SENDMSG:
|
|
case BPF_CGROUP_UDP6_SENDMSG:
|
|
ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
|
|
break;
|
|
case BPF_CGROUP_SOCK_OPS:
|
|
ptype = BPF_PROG_TYPE_SOCK_OPS;
|
|
break;
|
|
case BPF_CGROUP_DEVICE:
|
|
ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
|
|
break;
|
|
case BPF_SK_MSG_VERDICT:
|
|
ptype = BPF_PROG_TYPE_SK_MSG;
|
|
break;
|
|
case BPF_SK_SKB_STREAM_PARSER:
|
|
case BPF_SK_SKB_STREAM_VERDICT:
|
|
ptype = BPF_PROG_TYPE_SK_SKB;
|
|
break;
|
|
case BPF_LIRC_MODE2:
|
|
ptype = BPF_PROG_TYPE_LIRC_MODE2;
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
|
|
if (IS_ERR(prog))
|
|
return PTR_ERR(prog);
|
|
|
|
if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
|
|
bpf_prog_put(prog);
|
|
return -EINVAL;
|
|
}
|
|
|
|
switch (ptype) {
|
|
case BPF_PROG_TYPE_SK_SKB:
|
|
case BPF_PROG_TYPE_SK_MSG:
|
|
ret = sockmap_get_from_fd(attr, ptype, prog);
|
|
break;
|
|
case BPF_PROG_TYPE_LIRC_MODE2:
|
|
ret = lirc_prog_attach(attr, prog);
|
|
break;
|
|
default:
|
|
ret = cgroup_bpf_prog_attach(attr, ptype, prog);
|
|
}
|
|
|
|
if (ret)
|
|
bpf_prog_put(prog);
|
|
return ret;
|
|
}
|
|
|
|
#define BPF_PROG_DETACH_LAST_FIELD attach_type
|
|
|
|
static int bpf_prog_detach(const union bpf_attr *attr)
|
|
{
|
|
enum bpf_prog_type ptype;
|
|
|
|
if (!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (CHECK_ATTR(BPF_PROG_DETACH))
|
|
return -EINVAL;
|
|
|
|
switch (attr->attach_type) {
|
|
case BPF_CGROUP_INET_INGRESS:
|
|
case BPF_CGROUP_INET_EGRESS:
|
|
ptype = BPF_PROG_TYPE_CGROUP_SKB;
|
|
break;
|
|
case BPF_CGROUP_INET_SOCK_CREATE:
|
|
case BPF_CGROUP_INET4_POST_BIND:
|
|
case BPF_CGROUP_INET6_POST_BIND:
|
|
ptype = BPF_PROG_TYPE_CGROUP_SOCK;
|
|
break;
|
|
case BPF_CGROUP_INET4_BIND:
|
|
case BPF_CGROUP_INET6_BIND:
|
|
case BPF_CGROUP_INET4_CONNECT:
|
|
case BPF_CGROUP_INET6_CONNECT:
|
|
case BPF_CGROUP_UDP4_SENDMSG:
|
|
case BPF_CGROUP_UDP6_SENDMSG:
|
|
ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
|
|
break;
|
|
case BPF_CGROUP_SOCK_OPS:
|
|
ptype = BPF_PROG_TYPE_SOCK_OPS;
|
|
break;
|
|
case BPF_CGROUP_DEVICE:
|
|
ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
|
|
break;
|
|
case BPF_SK_MSG_VERDICT:
|
|
return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, NULL);
|
|
case BPF_SK_SKB_STREAM_PARSER:
|
|
case BPF_SK_SKB_STREAM_VERDICT:
|
|
return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, NULL);
|
|
case BPF_LIRC_MODE2:
|
|
return lirc_prog_detach(attr);
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return cgroup_bpf_prog_detach(attr, ptype);
|
|
}
|
|
|
|
#define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
|
|
|
|
static int bpf_prog_query(const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr)
|
|
{
|
|
if (!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
if (CHECK_ATTR(BPF_PROG_QUERY))
|
|
return -EINVAL;
|
|
if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
|
|
return -EINVAL;
|
|
|
|
switch (attr->query.attach_type) {
|
|
case BPF_CGROUP_INET_INGRESS:
|
|
case BPF_CGROUP_INET_EGRESS:
|
|
case BPF_CGROUP_INET_SOCK_CREATE:
|
|
case BPF_CGROUP_INET4_BIND:
|
|
case BPF_CGROUP_INET6_BIND:
|
|
case BPF_CGROUP_INET4_POST_BIND:
|
|
case BPF_CGROUP_INET6_POST_BIND:
|
|
case BPF_CGROUP_INET4_CONNECT:
|
|
case BPF_CGROUP_INET6_CONNECT:
|
|
case BPF_CGROUP_UDP4_SENDMSG:
|
|
case BPF_CGROUP_UDP6_SENDMSG:
|
|
case BPF_CGROUP_SOCK_OPS:
|
|
case BPF_CGROUP_DEVICE:
|
|
break;
|
|
case BPF_LIRC_MODE2:
|
|
return lirc_prog_query(attr, uattr);
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return cgroup_bpf_prog_query(attr, uattr);
|
|
}
|
|
|
|
#define BPF_PROG_TEST_RUN_LAST_FIELD test.duration
|
|
|
|
static int bpf_prog_test_run(const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr)
|
|
{
|
|
struct bpf_prog *prog;
|
|
int ret = -ENOTSUPP;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
if (CHECK_ATTR(BPF_PROG_TEST_RUN))
|
|
return -EINVAL;
|
|
|
|
prog = bpf_prog_get(attr->test.prog_fd);
|
|
if (IS_ERR(prog))
|
|
return PTR_ERR(prog);
|
|
|
|
if (prog->aux->ops->test_run)
|
|
ret = prog->aux->ops->test_run(prog, attr, uattr);
|
|
|
|
bpf_prog_put(prog);
|
|
return ret;
|
|
}
|
|
|
|
#define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
|
|
|
|
static int bpf_obj_get_next_id(const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr,
|
|
struct idr *idr,
|
|
spinlock_t *lock)
|
|
{
|
|
u32 next_id = attr->start_id;
|
|
int err = 0;
|
|
|
|
if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
|
|
return -EINVAL;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
next_id++;
|
|
spin_lock_bh(lock);
|
|
if (!idr_get_next(idr, &next_id))
|
|
err = -ENOENT;
|
|
spin_unlock_bh(lock);
|
|
|
|
if (!err)
|
|
err = put_user(next_id, &uattr->next_id);
|
|
|
|
return err;
|
|
}
|
|
|
|
#define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
|
|
|
|
static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
|
|
{
|
|
struct bpf_prog *prog;
|
|
u32 id = attr->prog_id;
|
|
int fd;
|
|
|
|
if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
|
|
return -EINVAL;
|
|
|
|
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);
|
|
|
|
if (IS_ERR(prog))
|
|
return PTR_ERR(prog);
|
|
|
|
fd = bpf_prog_new_fd(prog);
|
|
if (fd < 0)
|
|
bpf_prog_put(prog);
|
|
|
|
return fd;
|
|
}
|
|
|
|
#define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
|
|
|
|
static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
|
|
{
|
|
struct bpf_map *map;
|
|
u32 id = attr->map_id;
|
|
int f_flags;
|
|
int fd;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
|
|
attr->open_flags & ~BPF_OBJ_FLAG_MASK)
|
|
return -EINVAL;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
f_flags = bpf_get_file_flag(attr->open_flags);
|
|
if (f_flags < 0)
|
|
return f_flags;
|
|
|
|
spin_lock_bh(&map_idr_lock);
|
|
map = idr_find(&map_idr, id);
|
|
if (map)
|
|
map = bpf_map_inc_not_zero(map, true);
|
|
else
|
|
map = ERR_PTR(-ENOENT);
|
|
spin_unlock_bh(&map_idr_lock);
|
|
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
fd = bpf_map_new_fd(map, f_flags);
|
|
if (fd < 0)
|
|
bpf_map_put(map);
|
|
|
|
return fd;
|
|
}
|
|
|
|
static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
|
|
unsigned long addr)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < prog->aux->used_map_cnt; i++)
|
|
if (prog->aux->used_maps[i] == (void *)addr)
|
|
return prog->aux->used_maps[i];
|
|
return NULL;
|
|
}
|
|
|
|
static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
|
|
{
|
|
const struct bpf_map *map;
|
|
struct bpf_insn *insns;
|
|
u64 imm;
|
|
int i;
|
|
|
|
insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
|
|
GFP_USER);
|
|
if (!insns)
|
|
return insns;
|
|
|
|
for (i = 0; i < prog->len; i++) {
|
|
if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
|
|
insns[i].code = BPF_JMP | BPF_CALL;
|
|
insns[i].imm = BPF_FUNC_tail_call;
|
|
/* fall-through */
|
|
}
|
|
if (insns[i].code == (BPF_JMP | BPF_CALL) ||
|
|
insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
|
|
if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
|
|
insns[i].code = BPF_JMP | BPF_CALL;
|
|
if (!bpf_dump_raw_ok())
|
|
insns[i].imm = 0;
|
|
continue;
|
|
}
|
|
|
|
if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
|
|
continue;
|
|
|
|
imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
|
|
map = bpf_map_from_imm(prog, imm);
|
|
if (map) {
|
|
insns[i].src_reg = BPF_PSEUDO_MAP_FD;
|
|
insns[i].imm = map->id;
|
|
insns[i + 1].imm = 0;
|
|
continue;
|
|
}
|
|
|
|
if (!bpf_dump_raw_ok() &&
|
|
imm == (unsigned long)prog->aux) {
|
|
insns[i].imm = 0;
|
|
insns[i + 1].imm = 0;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
return insns;
|
|
}
|
|
|
|
static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
|
|
const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr)
|
|
{
|
|
struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
|
|
struct bpf_prog_info info = {};
|
|
u32 info_len = attr->info.info_len;
|
|
char __user *uinsns;
|
|
u32 ulen;
|
|
int err;
|
|
|
|
err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
|
|
if (err)
|
|
return err;
|
|
info_len = min_t(u32, sizeof(info), info_len);
|
|
|
|
if (copy_from_user(&info, uinfo, info_len))
|
|
return -EFAULT;
|
|
|
|
info.type = prog->type;
|
|
info.id = prog->aux->id;
|
|
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));
|
|
|
|
ulen = info.nr_map_ids;
|
|
info.nr_map_ids = prog->aux->used_map_cnt;
|
|
ulen = min_t(u32, info.nr_map_ids, ulen);
|
|
if (ulen) {
|
|
u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
|
|
u32 i;
|
|
|
|
for (i = 0; i < ulen; i++)
|
|
if (put_user(prog->aux->used_maps[i]->id,
|
|
&user_map_ids[i]))
|
|
return -EFAULT;
|
|
}
|
|
|
|
if (!capable(CAP_SYS_ADMIN)) {
|
|
info.jited_prog_len = 0;
|
|
info.xlated_prog_len = 0;
|
|
info.nr_jited_ksyms = 0;
|
|
goto done;
|
|
}
|
|
|
|
ulen = info.xlated_prog_len;
|
|
info.xlated_prog_len = bpf_prog_insn_size(prog);
|
|
if (info.xlated_prog_len && ulen) {
|
|
struct bpf_insn *insns_sanitized;
|
|
bool fault;
|
|
|
|
if (prog->blinded && !bpf_dump_raw_ok()) {
|
|
info.xlated_prog_insns = 0;
|
|
goto done;
|
|
}
|
|
insns_sanitized = bpf_insn_prepare_dump(prog);
|
|
if (!insns_sanitized)
|
|
return -ENOMEM;
|
|
uinsns = u64_to_user_ptr(info.xlated_prog_insns);
|
|
ulen = min_t(u32, info.xlated_prog_len, ulen);
|
|
fault = copy_to_user(uinsns, insns_sanitized, ulen);
|
|
kfree(insns_sanitized);
|
|
if (fault)
|
|
return -EFAULT;
|
|
}
|
|
|
|
if (bpf_prog_is_dev_bound(prog->aux)) {
|
|
err = bpf_prog_offload_info_fill(&info, prog);
|
|
if (err)
|
|
return err;
|
|
goto done;
|
|
}
|
|
|
|
/* NOTE: the following code is supposed to be skipped for offload.
|
|
* bpf_prog_offload_info_fill() is the place to fill similar fields
|
|
* for offload.
|
|
*/
|
|
ulen = info.jited_prog_len;
|
|
if (prog->aux->func_cnt) {
|
|
u32 i;
|
|
|
|
info.jited_prog_len = 0;
|
|
for (i = 0; i < prog->aux->func_cnt; i++)
|
|
info.jited_prog_len += prog->aux->func[i]->jited_len;
|
|
} else {
|
|
info.jited_prog_len = prog->jited_len;
|
|
}
|
|
|
|
if (info.jited_prog_len && ulen) {
|
|
if (bpf_dump_raw_ok()) {
|
|
uinsns = u64_to_user_ptr(info.jited_prog_insns);
|
|
ulen = min_t(u32, info.jited_prog_len, ulen);
|
|
|
|
/* for multi-function programs, copy the JITed
|
|
* instructions for all the functions
|
|
*/
|
|
if (prog->aux->func_cnt) {
|
|
u32 len, free, i;
|
|
u8 *img;
|
|
|
|
free = ulen;
|
|
for (i = 0; i < prog->aux->func_cnt; i++) {
|
|
len = prog->aux->func[i]->jited_len;
|
|
len = min_t(u32, len, free);
|
|
img = (u8 *) prog->aux->func[i]->bpf_func;
|
|
if (copy_to_user(uinsns, img, len))
|
|
return -EFAULT;
|
|
uinsns += len;
|
|
free -= len;
|
|
if (!free)
|
|
break;
|
|
}
|
|
} else {
|
|
if (copy_to_user(uinsns, prog->bpf_func, ulen))
|
|
return -EFAULT;
|
|
}
|
|
} else {
|
|
info.jited_prog_insns = 0;
|
|
}
|
|
}
|
|
|
|
ulen = info.nr_jited_ksyms;
|
|
info.nr_jited_ksyms = prog->aux->func_cnt;
|
|
if (info.nr_jited_ksyms && ulen) {
|
|
if (bpf_dump_raw_ok()) {
|
|
u64 __user *user_ksyms;
|
|
ulong ksym_addr;
|
|
u32 i;
|
|
|
|
/* copy the address of the kernel symbol
|
|
* corresponding to each function
|
|
*/
|
|
ulen = min_t(u32, info.nr_jited_ksyms, ulen);
|
|
user_ksyms = u64_to_user_ptr(info.jited_ksyms);
|
|
for (i = 0; i < ulen; i++) {
|
|
ksym_addr = (ulong) prog->aux->func[i]->bpf_func;
|
|
ksym_addr &= PAGE_MASK;
|
|
if (put_user((u64) ksym_addr, &user_ksyms[i]))
|
|
return -EFAULT;
|
|
}
|
|
} else {
|
|
info.jited_ksyms = 0;
|
|
}
|
|
}
|
|
|
|
ulen = info.nr_jited_func_lens;
|
|
info.nr_jited_func_lens = prog->aux->func_cnt;
|
|
if (info.nr_jited_func_lens && ulen) {
|
|
if (bpf_dump_raw_ok()) {
|
|
u32 __user *user_lens;
|
|
u32 func_len, i;
|
|
|
|
/* copy the JITed image lengths for each function */
|
|
ulen = min_t(u32, info.nr_jited_func_lens, ulen);
|
|
user_lens = u64_to_user_ptr(info.jited_func_lens);
|
|
for (i = 0; i < ulen; i++) {
|
|
func_len = prog->aux->func[i]->jited_len;
|
|
if (put_user(func_len, &user_lens[i]))
|
|
return -EFAULT;
|
|
}
|
|
} else {
|
|
info.jited_func_lens = 0;
|
|
}
|
|
}
|
|
|
|
done:
|
|
if (copy_to_user(uinfo, &info, info_len) ||
|
|
put_user(info_len, &uattr->info.info_len))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bpf_map_get_info_by_fd(struct bpf_map *map,
|
|
const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr)
|
|
{
|
|
struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
|
|
struct bpf_map_info info = {};
|
|
u32 info_len = attr->info.info_len;
|
|
int err;
|
|
|
|
err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
|
|
if (err)
|
|
return err;
|
|
info_len = min_t(u32, sizeof(info), info_len);
|
|
|
|
info.type = map->map_type;
|
|
info.id = map->id;
|
|
info.key_size = map->key_size;
|
|
info.value_size = map->value_size;
|
|
info.max_entries = map->max_entries;
|
|
info.map_flags = map->map_flags;
|
|
memcpy(info.name, map->name, sizeof(map->name));
|
|
|
|
if (map->btf) {
|
|
info.btf_id = btf_id(map->btf);
|
|
info.btf_key_type_id = map->btf_key_type_id;
|
|
info.btf_value_type_id = map->btf_value_type_id;
|
|
}
|
|
|
|
if (bpf_map_is_dev_bound(map)) {
|
|
err = bpf_map_offload_info_fill(&info, map);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
if (copy_to_user(uinfo, &info, info_len) ||
|
|
put_user(info_len, &uattr->info.info_len))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bpf_btf_get_info_by_fd(struct btf *btf,
|
|
const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr)
|
|
{
|
|
struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
|
|
u32 info_len = attr->info.info_len;
|
|
int err;
|
|
|
|
err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
|
|
if (err)
|
|
return err;
|
|
|
|
return btf_get_info_by_fd(btf, attr, uattr);
|
|
}
|
|
|
|
#define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
|
|
|
|
static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr)
|
|
{
|
|
int ufd = attr->info.bpf_fd;
|
|
struct fd f;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
|
|
return -EINVAL;
|
|
|
|
f = fdget(ufd);
|
|
if (!f.file)
|
|
return -EBADFD;
|
|
|
|
if (f.file->f_op == &bpf_prog_fops)
|
|
err = bpf_prog_get_info_by_fd(f.file->private_data, attr,
|
|
uattr);
|
|
else if (f.file->f_op == &bpf_map_fops)
|
|
err = bpf_map_get_info_by_fd(f.file->private_data, attr,
|
|
uattr);
|
|
else if (f.file->f_op == &btf_fops)
|
|
err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr);
|
|
else
|
|
err = -EINVAL;
|
|
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
#define BPF_BTF_LOAD_LAST_FIELD btf_log_level
|
|
|
|
static int bpf_btf_load(const union bpf_attr *attr)
|
|
{
|
|
if (CHECK_ATTR(BPF_BTF_LOAD))
|
|
return -EINVAL;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
return btf_new_fd(attr);
|
|
}
|
|
|
|
#define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
|
|
|
|
static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
|
|
{
|
|
if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
|
|
return -EINVAL;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
return btf_get_fd_by_id(attr->btf_id);
|
|
}
|
|
|
|
static int bpf_task_fd_query_copy(const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr,
|
|
u32 prog_id, u32 fd_type,
|
|
const char *buf, u64 probe_offset,
|
|
u64 probe_addr)
|
|
{
|
|
char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
|
|
u32 len = buf ? strlen(buf) : 0, input_len;
|
|
int err = 0;
|
|
|
|
if (put_user(len, &uattr->task_fd_query.buf_len))
|
|
return -EFAULT;
|
|
input_len = attr->task_fd_query.buf_len;
|
|
if (input_len && ubuf) {
|
|
if (!len) {
|
|
/* nothing to copy, just make ubuf NULL terminated */
|
|
char zero = '\0';
|
|
|
|
if (put_user(zero, ubuf))
|
|
return -EFAULT;
|
|
} else if (input_len >= len + 1) {
|
|
/* ubuf can hold the string with NULL terminator */
|
|
if (copy_to_user(ubuf, buf, len + 1))
|
|
return -EFAULT;
|
|
} else {
|
|
/* ubuf cannot hold the string with NULL terminator,
|
|
* do a partial copy with NULL terminator.
|
|
*/
|
|
char zero = '\0';
|
|
|
|
err = -ENOSPC;
|
|
if (copy_to_user(ubuf, buf, input_len - 1))
|
|
return -EFAULT;
|
|
if (put_user(zero, ubuf + input_len - 1))
|
|
return -EFAULT;
|
|
}
|
|
}
|
|
|
|
if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
|
|
put_user(fd_type, &uattr->task_fd_query.fd_type) ||
|
|
put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
|
|
put_user(probe_addr, &uattr->task_fd_query.probe_addr))
|
|
return -EFAULT;
|
|
|
|
return err;
|
|
}
|
|
|
|
#define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
|
|
|
|
static int bpf_task_fd_query(const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr)
|
|
{
|
|
pid_t pid = attr->task_fd_query.pid;
|
|
u32 fd = attr->task_fd_query.fd;
|
|
const struct perf_event *event;
|
|
struct files_struct *files;
|
|
struct task_struct *task;
|
|
struct file *file;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_TASK_FD_QUERY))
|
|
return -EINVAL;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (attr->task_fd_query.flags != 0)
|
|
return -EINVAL;
|
|
|
|
task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
|
|
if (!task)
|
|
return -ENOENT;
|
|
|
|
files = get_files_struct(task);
|
|
put_task_struct(task);
|
|
if (!files)
|
|
return -ENOENT;
|
|
|
|
err = 0;
|
|
spin_lock(&files->file_lock);
|
|
file = fcheck_files(files, fd);
|
|
if (!file)
|
|
err = -EBADF;
|
|
else
|
|
get_file(file);
|
|
spin_unlock(&files->file_lock);
|
|
put_files_struct(files);
|
|
|
|
if (err)
|
|
goto out;
|
|
|
|
if (file->f_op == &bpf_raw_tp_fops) {
|
|
struct bpf_raw_tracepoint *raw_tp = file->private_data;
|
|
struct bpf_raw_event_map *btp = raw_tp->btp;
|
|
|
|
err = bpf_task_fd_query_copy(attr, uattr,
|
|
raw_tp->prog->aux->id,
|
|
BPF_FD_TYPE_RAW_TRACEPOINT,
|
|
btp->tp->name, 0, 0);
|
|
goto put_file;
|
|
}
|
|
|
|
event = perf_get_event(file);
|
|
if (!IS_ERR(event)) {
|
|
u64 probe_offset, probe_addr;
|
|
u32 prog_id, fd_type;
|
|
const char *buf;
|
|
|
|
err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
|
|
&buf, &probe_offset,
|
|
&probe_addr);
|
|
if (!err)
|
|
err = bpf_task_fd_query_copy(attr, uattr, prog_id,
|
|
fd_type, buf,
|
|
probe_offset,
|
|
probe_addr);
|
|
goto put_file;
|
|
}
|
|
|
|
err = -ENOTSUPP;
|
|
put_file:
|
|
fput(file);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
|
|
{
|
|
union bpf_attr attr = {};
|
|
int err;
|
|
|
|
if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
|
|
if (err)
|
|
return err;
|
|
size = min_t(u32, size, sizeof(attr));
|
|
|
|
/* copy attributes from user space, may be less than sizeof(bpf_attr) */
|
|
if (copy_from_user(&attr, uattr, size) != 0)
|
|
return -EFAULT;
|
|
|
|
err = security_bpf(cmd, &attr, size);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
switch (cmd) {
|
|
case BPF_MAP_CREATE:
|
|
err = map_create(&attr);
|
|
break;
|
|
case BPF_MAP_LOOKUP_ELEM:
|
|
err = map_lookup_elem(&attr);
|
|
break;
|
|
case BPF_MAP_UPDATE_ELEM:
|
|
err = map_update_elem(&attr);
|
|
break;
|
|
case BPF_MAP_DELETE_ELEM:
|
|
err = map_delete_elem(&attr);
|
|
break;
|
|
case BPF_MAP_GET_NEXT_KEY:
|
|
err = map_get_next_key(&attr);
|
|
break;
|
|
case BPF_PROG_LOAD:
|
|
err = bpf_prog_load(&attr);
|
|
break;
|
|
case BPF_OBJ_PIN:
|
|
err = bpf_obj_pin(&attr);
|
|
break;
|
|
case BPF_OBJ_GET:
|
|
err = bpf_obj_get(&attr);
|
|
break;
|
|
case BPF_PROG_ATTACH:
|
|
err = bpf_prog_attach(&attr);
|
|
break;
|
|
case BPF_PROG_DETACH:
|
|
err = bpf_prog_detach(&attr);
|
|
break;
|
|
case BPF_PROG_QUERY:
|
|
err = bpf_prog_query(&attr, uattr);
|
|
break;
|
|
case BPF_PROG_TEST_RUN:
|
|
err = bpf_prog_test_run(&attr, uattr);
|
|
break;
|
|
case BPF_PROG_GET_NEXT_ID:
|
|
err = bpf_obj_get_next_id(&attr, uattr,
|
|
&prog_idr, &prog_idr_lock);
|
|
break;
|
|
case BPF_MAP_GET_NEXT_ID:
|
|
err = bpf_obj_get_next_id(&attr, uattr,
|
|
&map_idr, &map_idr_lock);
|
|
break;
|
|
case BPF_PROG_GET_FD_BY_ID:
|
|
err = bpf_prog_get_fd_by_id(&attr);
|
|
break;
|
|
case BPF_MAP_GET_FD_BY_ID:
|
|
err = bpf_map_get_fd_by_id(&attr);
|
|
break;
|
|
case BPF_OBJ_GET_INFO_BY_FD:
|
|
err = bpf_obj_get_info_by_fd(&attr, uattr);
|
|
break;
|
|
case BPF_RAW_TRACEPOINT_OPEN:
|
|
err = bpf_raw_tracepoint_open(&attr);
|
|
break;
|
|
case BPF_BTF_LOAD:
|
|
err = bpf_btf_load(&attr);
|
|
break;
|
|
case BPF_BTF_GET_FD_BY_ID:
|
|
err = bpf_btf_get_fd_by_id(&attr);
|
|
break;
|
|
case BPF_TASK_FD_QUERY:
|
|
err = bpf_task_fd_query(&attr, uattr);
|
|
break;
|
|
default:
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
return err;
|
|
}
|