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

Qi Zheng
2023-06-26T01:48:23Z

On 2023/6/25 23:49, Qi Zheng wrote:
> 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>

Oh, I forgot to add Fixes tag:

Fixes: f2517eb76f1f ("android: binder: Add global lru shrinker to binder")

> ---
> 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,