[PATCH] binder: fix memory leak in binder_init()

Qi Zheng
2023-06-25T15:50:17Z

From: Qi Zheng <zhengqi.arch@bytedance.com>

In binder_init(), the destruction of binder_alloc_shrinker_init() is not
performed in the wrong path, which will cause memory leaks. So this commit
introduces binder_alloc_shrinker_exit() and calls it in the wrong path to
fix that.

Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
---
drivers/android/binder.c | 1 +
drivers/android/binder_alloc.c | 6 ++++++
drivers/android/binder_alloc.h | 1 +
3 files changed, 8 insertions(+)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 486c8271cab7..d720f93d8b19 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -6617,6 +6617,7 @@ static int __init binder_init(void)

err_alloc_device_names_failed:
debugfs_remove_recursive(binder_debugfs_dir_entry_root);
+ binder_alloc_shrinker_exit();

return ret;
}
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index 662a2a2e2e84..e3db8297095a 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -1087,6 +1087,12 @@ int binder_alloc_shrinker_init(void)
return ret;
}

+void binder_alloc_shrinker_exit(void)
+{
+ unregister_shrinker(&binder_shrinker);
+ list_lru_destroy(&binder_alloc_lru);
+}
+
/**
* check_buffer() - verify that buffer/offset is safe to access
* @alloc: binder_alloc for this proc
diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h
index 138d1d5af9ce..dc1e2b01dd64 100644
--- a/drivers/android/binder_alloc.h
+++ b/drivers/android/binder_alloc.h
@@ -129,6 +129,7 @@ extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
int pid);
extern void binder_alloc_init(struct binder_alloc *alloc);
extern int binder_alloc_shrinker_init(void);
+extern void binder_alloc_shrinker_exit(void);
extern void binder_alloc_vma_close(struct binder_alloc *alloc);
extern struct binder_buffer *
binder_alloc_prepare_to_free(struct binder_alloc *alloc,
--
2.30.2