[PATCH 4.14.y] binder: fix memory leak in binder_init()

[Carlos Llamas <cmllamas@google.com>]

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

commit adb9743d6a08778b78d62d16b4230346d3508986 upstream.

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>
Acked-by: Carlos Llamas <cmllamas@google.com>
Fixes: f2517eb76f1f ("android: binder: Add global lru shrinker to binder")
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20230625154937.64316-1-qi.zheng@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[cmllamas: resolved trivial merge conflicts]
Signed-off-by: Carlos Llamas <cmllamas@google.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 c07a304af8a3..95c9f81a514a 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5658,6 +5658,7 @@ 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 1687368ea71f..f7f0b71c9f68 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -1033,3 +1033,9 @@ void binder_alloc_shrinker_init(void)
 	list_lru_init(&binder_alloc_lru);
 	register_shrinker(&binder_shrinker);
 }
+
+void binder_alloc_shrinker_exit(void)
+{
+	unregister_shrinker(&binder_shrinker);
+	list_lru_destroy(&binder_alloc_lru);
+}
diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h
index a3ad7683b6f2..7efcb46c0083 100644
--- a/drivers/android/binder_alloc.h
+++ b/drivers/android/binder_alloc.h
@@ -128,6 +128,7 @@ extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
 						  int is_async);
 extern void binder_alloc_init(struct binder_alloc *alloc);
 void 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,
-- 
2.41.0.694.ge786442a9b-goog