Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

[linux.git] / kernel / bpf / syscall.c

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 178c147350f563570852ce6310be6200b7807386..34268491d2dec751633cc30e8b5d9528960f69e5 100644 (file)
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2345,12 +2345,8 @@ void bpf_link_put(struct bpf_link *link)
        if (!atomic64_dec_and_test(&link->refcnt))
                return;
 
-       if (in_atomic()) {
-               INIT_WORK(&link->work, bpf_link_put_deferred);
-               schedule_work(&link->work);
-       } else {
-               bpf_link_free(link);
-       }
+       INIT_WORK(&link->work, bpf_link_put_deferred);
+       schedule_work(&link->work);
 }
 
 static int bpf_link_release(struct inode *inode, struct file *filp)
@@ -3162,21 +3158,25 @@ static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
        const struct bpf_map *map;
        int i;
 
+       mutex_lock(&prog->aux->used_maps_mutex);
        for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
                map = prog->aux->used_maps[i];
                if (map == (void *)addr) {
                        *type = BPF_PSEUDO_MAP_FD;
-                       return map;
+                       goto out;
                }
                if (!map->ops->map_direct_value_meta)
                        continue;
                if (!map->ops->map_direct_value_meta(map, addr, off)) {
                        *type = BPF_PSEUDO_MAP_VALUE;
-                       return map;
+                       goto out;
                }
        }
+       map = NULL;
 
-       return NULL;
+out:
+       mutex_unlock(&prog->aux->used_maps_mutex);
+       return map;
 }
 
 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
@@ -3294,6 +3294,7 @@ static int bpf_prog_get_info_by_fd(struct file *file,
        memcpy(info.tag, prog->tag, sizeof(prog->tag));
        memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
 
+       mutex_lock(&prog->aux->used_maps_mutex);
        ulen = info.nr_map_ids;
        info.nr_map_ids = prog->aux->used_map_cnt;
        ulen = min_t(u32, info.nr_map_ids, ulen);
@@ -3303,9 +3304,12 @@ static int bpf_prog_get_info_by_fd(struct file *file,
 
                for (i = 0; i < ulen; i++)
                        if (put_user(prog->aux->used_maps[i]->id,
-                                    &user_map_ids[i]))
+                                    &user_map_ids[i])) {
+                               mutex_unlock(&prog->aux->used_maps_mutex);
                                return -EFAULT;
+                       }
        }
+       mutex_unlock(&prog->aux->used_maps_mutex);
 
        err = set_info_rec_size(&info);
        if (err)
@@ -4153,6 +4157,66 @@ static int bpf_iter_create(union bpf_attr *attr)
        return err;
 }
 
+#define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
+
+static int bpf_prog_bind_map(union bpf_attr *attr)
+{
+       struct bpf_prog *prog;
+       struct bpf_map *map;
+       struct bpf_map **used_maps_old, **used_maps_new;
+       int i, ret = 0;
+
+       if (CHECK_ATTR(BPF_PROG_BIND_MAP))
+               return -EINVAL;
+
+       if (attr->prog_bind_map.flags)
+               return -EINVAL;
+
+       prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
+       if (IS_ERR(prog))
+               return PTR_ERR(prog);
+
+       map = bpf_map_get(attr->prog_bind_map.map_fd);
+       if (IS_ERR(map)) {
+               ret = PTR_ERR(map);
+               goto out_prog_put;
+       }
+
+       mutex_lock(&prog->aux->used_maps_mutex);
+
+       used_maps_old = prog->aux->used_maps;
+
+       for (i = 0; i < prog->aux->used_map_cnt; i++)
+               if (used_maps_old[i] == map)
+                       goto out_unlock;
+
+       used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
+                                     sizeof(used_maps_new[0]),
+                                     GFP_KERNEL);
+       if (!used_maps_new) {
+               ret = -ENOMEM;
+               goto out_unlock;
+       }
+
+       memcpy(used_maps_new, used_maps_old,
+              sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
+       used_maps_new[prog->aux->used_map_cnt] = map;
+
+       prog->aux->used_map_cnt++;
+       prog->aux->used_maps = used_maps_new;
+
+       kfree(used_maps_old);
+
+out_unlock:
+       mutex_unlock(&prog->aux->used_maps_mutex);
+
+       if (ret)
+               bpf_map_put(map);
+out_prog_put:
+       bpf_prog_put(prog);
+       return ret;
+}
+
 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
 {
        union bpf_attr attr;
@@ -4286,6 +4350,9 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
        case BPF_LINK_DETACH:
                err = link_detach(&attr);
                break;
+       case BPF_PROG_BIND_MAP:
+               err = bpf_prog_bind_map(&attr);
+               break;
        default:
                err = -EINVAL;
                break;