aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/bpf/syscall.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/bpf/syscall.c')
-rw-r--r--kernel/bpf/syscall.c28
1 files changed, 23 insertions, 5 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 5742df21598c..f4ecd6ed2252 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -719,10 +719,15 @@ static int map_lookup_elem(union bpf_attr *attr)
} else {
rcu_read_lock();
ptr = map->ops->map_lookup_elem(map, key);
- if (ptr)
+ if (IS_ERR(ptr)) {
+ err = PTR_ERR(ptr);
+ } else if (!ptr) {
+ err = -ENOENT;
+ } else {
+ err = 0;
memcpy(value, ptr, value_size);
+ }
rcu_read_unlock();
- err = ptr ? 0 : -ENOENT;
}
if (err)
@@ -743,6 +748,17 @@ err_put:
return err;
}
+static void maybe_wait_bpf_programs(struct bpf_map *map)
+{
+ /* Wait for any running BPF programs to complete so that
+ * userspace, when we return to it, knows that all programs
+ * that could be running use the new map value.
+ */
+ if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
+ map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
+ synchronize_rcu();
+}
+
#define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
static int map_update_elem(union bpf_attr *attr)
@@ -837,6 +853,7 @@ static int map_update_elem(union bpf_attr *attr)
}
__this_cpu_dec(bpf_prog_active);
preempt_enable();
+ maybe_wait_bpf_programs(map);
out:
free_value:
kfree(value);
@@ -889,6 +906,7 @@ static int map_delete_elem(union bpf_attr *attr)
rcu_read_unlock();
__this_cpu_dec(bpf_prog_active);
preempt_enable();
+ maybe_wait_bpf_programs(map);
out:
kfree(key);
err_put:
@@ -1646,7 +1664,7 @@ static int bpf_prog_attach(const union bpf_attr *attr)
switch (ptype) {
case BPF_PROG_TYPE_SK_SKB:
case BPF_PROG_TYPE_SK_MSG:
- ret = sockmap_get_from_fd(attr, ptype, prog);
+ ret = sock_map_get_from_fd(attr, prog);
break;
case BPF_PROG_TYPE_LIRC_MODE2:
ret = lirc_prog_attach(attr, prog);
@@ -1700,10 +1718,10 @@ static int bpf_prog_detach(const union bpf_attr *attr)
ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
break;
case BPF_SK_MSG_VERDICT:
- return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, NULL);
+ return sock_map_get_from_fd(attr, 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);
+ return sock_map_get_from_fd(attr, NULL);
case BPF_LIRC_MODE2:
return lirc_prog_detach(attr);
case BPF_FLOW_DISSECTOR: