1 files changed, 74 insertions, 28 deletions

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index bfedcbdb4d84..5af30732697b 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -427,59 +427,105 @@ static int __init register_prog_array_map(void)
 }
 late_initcall(register_prog_array_map);
 
-static void perf_event_array_map_free(struct bpf_map *map)
+static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file,
+                                                   struct file *map_file)
 {
-        bpf_fd_array_map_clear(map);
-        fd_array_map_free(map);
+        struct bpf_event_entry *ee;
+
+        ee = kzalloc(sizeof(*ee), GFP_KERNEL);
+        if (ee) {
+                ee->event = perf_file->private_data;
+                ee->perf_file = perf_file;
+                ee->map_file = map_file;
+        }
+
+        return ee;
+}
+
+static void __bpf_event_entry_free(struct rcu_head *rcu)
+{
+        struct bpf_event_entry *ee;
+
+        ee = container_of(rcu, struct bpf_event_entry, rcu);
+        fput(ee->perf_file);
+        kfree(ee);
+}
+
+static void bpf_event_entry_free_rcu(struct bpf_event_entry *ee)
+{
+        call_rcu(&ee->rcu, __bpf_event_entry_free);
 }
 
 static void *perf_event_fd_array_get_ptr(struct bpf_map *map,
                                          struct file *map_file, int fd)
 {
-        struct perf_event *event;
         const struct perf_event_attr *attr;
-        struct file *file;
+        struct bpf_event_entry *ee;
+        struct perf_event *event;
+        struct file *perf_file;
 
-        file = perf_event_get(fd);
-        if (IS_ERR(file))
-                return file;
+        perf_file = perf_event_get(fd);
+        if (IS_ERR(perf_file))
+                return perf_file;
 
-        event = file->private_data;
+        event = perf_file->private_data;
+        ee = ERR_PTR(-EINVAL);
 
         attr = perf_event_attrs(event);
-        if (IS_ERR(attr))
-                goto err;
-
-        if (attr->inherit)
-                goto err;
-
-        if (attr->type == PERF_TYPE_RAW)
-                return file;
-
-        if (attr->type == PERF_TYPE_HARDWARE)
-                return file;
+        if (IS_ERR(attr) || attr->inherit)
+                goto err_out;
+
+        switch (attr->type) {
+        case PERF_TYPE_SOFTWARE:
+                if (attr->config != PERF_COUNT_SW_BPF_OUTPUT)
+                        goto err_out;
+                /* fall-through */
+        case PERF_TYPE_RAW:
+        case PERF_TYPE_HARDWARE:
+                ee = bpf_event_entry_gen(perf_file, map_file);
+                if (ee)
+                        return ee;
+                ee = ERR_PTR(-ENOMEM);
+                /* fall-through */
+        default:
+                break;
+        }
 
-        if (attr->type == PERF_TYPE_SOFTWARE &&
-            attr->config == PERF_COUNT_SW_BPF_OUTPUT)
-                return file;
-err:
-        fput(file);
-        return ERR_PTR(-EINVAL);
+err_out:
+        fput(perf_file);
+        return ee;
 }
 
 static void perf_event_fd_array_put_ptr(void *ptr)
 {
-        fput((struct file *)ptr);
+        bpf_event_entry_free_rcu(ptr);
+}
+
+static void perf_event_fd_array_release(struct bpf_map *map,
+                                        struct file *map_file)
+{
+        struct bpf_array *array = container_of(map, struct bpf_array, map);
+        struct bpf_event_entry *ee;
+        int i;
+
+        rcu_read_lock();
+        for (i = 0; i < array->map.max_entries; i++) {
+                ee = READ_ONCE(array->ptrs[i]);
+                if (ee && ee->map_file == map_file)
+                        fd_array_map_delete_elem(map, &i);
+        }
+        rcu_read_unlock();
 }
 
 static const struct bpf_map_ops perf_event_array_ops = {
         .map_alloc = fd_array_map_alloc,
-        .map_free = perf_event_array_map_free,
+        .map_free = fd_array_map_free,
         .map_get_next_key = array_map_get_next_key,
         .map_lookup_elem = fd_array_map_lookup_elem,
         .map_delete_elem = fd_array_map_delete_elem,
         .map_fd_get_ptr = perf_event_fd_array_get_ptr,
         .map_fd_put_ptr = perf_event_fd_array_put_ptr,
+        .map_release = perf_event_fd_array_release,
 };
 
 static struct bpf_map_type_list perf_event_array_type __read_mostly = {