diff options
Diffstat (limited to 'kernel/bpf/syscall.c')
-rw-r--r-- | kernel/bpf/syscall.c | 130 |
1 files changed, 111 insertions, 19 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 237f3d6a7ddc..1090d16a31c1 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -17,6 +17,7 @@ #include <linux/license.h> #include <linux/filter.h> #include <linux/version.h> +#include <linux/kernel.h> DEFINE_PER_CPU(int, bpf_prog_active); @@ -254,12 +255,6 @@ struct bpf_map *bpf_map_get_with_uref(u32 ufd) return map; } -/* helper to convert user pointers passed inside __aligned_u64 fields */ -static void __user *u64_to_ptr(__u64 val) -{ - return (void __user *) (unsigned long) val; -} - int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) { return -ENOTSUPP; @@ -270,8 +265,8 @@ int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) static int map_lookup_elem(union bpf_attr *attr) { - void __user *ukey = u64_to_ptr(attr->key); - void __user *uvalue = u64_to_ptr(attr->value); + 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; @@ -297,6 +292,7 @@ static int map_lookup_elem(union bpf_attr *attr) goto free_key; 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 @@ -307,7 +303,8 @@ static int map_lookup_elem(union bpf_attr *attr) if (!value) goto free_key; - if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH) { + 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); @@ -344,8 +341,8 @@ err_put: static int map_update_elem(union bpf_attr *attr) { - void __user *ukey = u64_to_ptr(attr->key); - void __user *uvalue = u64_to_ptr(attr->value); + 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; @@ -371,6 +368,7 @@ static int map_update_elem(union bpf_attr *attr) goto free_key; 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 @@ -390,7 +388,8 @@ static int map_update_elem(union bpf_attr *attr) */ preempt_disable(); __this_cpu_inc(bpf_prog_active); - if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH) { + 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); @@ -422,7 +421,7 @@ err_put: static int map_delete_elem(union bpf_attr *attr) { - void __user *ukey = u64_to_ptr(attr->key); + void __user *ukey = u64_to_user_ptr(attr->key); int ufd = attr->map_fd; struct bpf_map *map; struct fd f; @@ -466,8 +465,8 @@ err_put: static int map_get_next_key(union bpf_attr *attr) { - void __user *ukey = u64_to_ptr(attr->key); - void __user *unext_key = u64_to_ptr(attr->next_key); + 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; @@ -682,10 +681,22 @@ struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i) } 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); static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *type) { @@ -732,7 +743,7 @@ static int bpf_prog_load(union bpf_attr *attr) return -EINVAL; /* copy eBPF program license from user space */ - if (strncpy_from_user(license, u64_to_ptr(attr->license), + if (strncpy_from_user(license, u64_to_user_ptr(attr->license), sizeof(license) - 1) < 0) return -EFAULT; license[sizeof(license) - 1] = 0; @@ -762,7 +773,7 @@ static int bpf_prog_load(union bpf_attr *attr) prog->len = attr->insn_cnt; err = -EFAULT; - if (copy_from_user(prog->insns, u64_to_ptr(attr->insns), + if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), prog->len * sizeof(struct bpf_insn)) != 0) goto free_prog; @@ -813,7 +824,7 @@ static int bpf_obj_pin(const union bpf_attr *attr) if (CHECK_ATTR(BPF_OBJ)) return -EINVAL; - return bpf_obj_pin_user(attr->bpf_fd, u64_to_ptr(attr->pathname)); + return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); } static int bpf_obj_get(const union bpf_attr *attr) @@ -821,9 +832,80 @@ static int bpf_obj_get(const union bpf_attr *attr) if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0) return -EINVAL; - return bpf_obj_get_user(u64_to_ptr(attr->pathname)); + return bpf_obj_get_user(u64_to_user_ptr(attr->pathname)); } +#ifdef CONFIG_CGROUP_BPF + +#define BPF_PROG_ATTACH_LAST_FIELD attach_type + +static int bpf_prog_attach(const union bpf_attr *attr) +{ + struct bpf_prog *prog; + struct cgroup *cgrp; + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + if (CHECK_ATTR(BPF_PROG_ATTACH)) + return -EINVAL; + + switch (attr->attach_type) { + case BPF_CGROUP_INET_INGRESS: + case BPF_CGROUP_INET_EGRESS: + prog = bpf_prog_get_type(attr->attach_bpf_fd, + BPF_PROG_TYPE_CGROUP_SKB); + if (IS_ERR(prog)) + return PTR_ERR(prog); + + cgrp = cgroup_get_from_fd(attr->target_fd); + if (IS_ERR(cgrp)) { + bpf_prog_put(prog); + return PTR_ERR(cgrp); + } + + cgroup_bpf_update(cgrp, prog, attr->attach_type); + cgroup_put(cgrp); + break; + + default: + return -EINVAL; + } + + return 0; +} + +#define BPF_PROG_DETACH_LAST_FIELD attach_type + +static int bpf_prog_detach(const union bpf_attr *attr) +{ + struct cgroup *cgrp; + + 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: + cgrp = cgroup_get_from_fd(attr->target_fd); + if (IS_ERR(cgrp)) + return PTR_ERR(cgrp); + + cgroup_bpf_update(cgrp, NULL, attr->attach_type); + cgroup_put(cgrp); + break; + + default: + return -EINVAL; + } + + return 0; +} +#endif /* CONFIG_CGROUP_BPF */ + SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) { union bpf_attr attr = {}; @@ -890,6 +972,16 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz case BPF_OBJ_GET: err = bpf_obj_get(&attr); break; + +#ifdef CONFIG_CGROUP_BPF + case BPF_PROG_ATTACH: + err = bpf_prog_attach(&attr); + break; + case BPF_PROG_DETACH: + err = bpf_prog_detach(&attr); + break; +#endif + default: err = -EINVAL; break; |