#include <linux/filter.h>
#include <linux/version.h>
+DEFINE_PER_CPU(int, bpf_prog_active);
+
int sysctl_unprivileged_bpf_disabled __read_mostly;
static LIST_HEAD(bpf_map_types);
list_add(&tl->list_node, &bpf_map_types);
}
+int bpf_map_precharge_memlock(u32 pages)
+{
+ struct user_struct *user = get_current_user();
+ unsigned long memlock_limit, cur;
+
+ memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ cur = atomic_long_read(&user->locked_vm);
+ free_uid(user);
+ if (cur + pages > memlock_limit)
+ return -EPERM;
+ return 0;
+}
+
static int bpf_map_charge_memlock(struct bpf_map *map)
{
struct user_struct *user = get_current_user();
offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
sizeof(attr->CMD##_LAST_FIELD)) != NULL
-#define BPF_MAP_CREATE_LAST_FIELD max_entries
+#define BPF_MAP_CREATE_LAST_FIELD map_flags
/* called via syscall */
static int map_create(union bpf_attr *attr)
{
return (void __user *) (unsigned long) val;
}
+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
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 {
rcu_read_lock();
ptr = map->ops->map_lookup_elem(map, key);
if (copy_from_user(value, uvalue, value_size) != 0)
goto free_value;
+ /* 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) {
err = bpf_percpu_hash_update(map, key, value, attr->flags);
} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
err = map->ops->map_update_elem(map, key, value, attr->flags);
rcu_read_unlock();
}
+ __this_cpu_dec(bpf_prog_active);
+ preempt_enable();
free_value:
kfree(value);
if (copy_from_user(key, ukey, map->key_size) != 0)
goto free_key;
+ 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();
free_key:
kfree(key);