2023-06-25 16:08:10

by Qi Zheng

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

From: Qi Zheng <[email protected]>

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 <[email protected]>
---
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

2023-06-25 16:29:48

by Carlos Llamas

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

On Sun, Jun 25, 2023 at 03:49:37PM +0000, Qi Zheng wrote:
> From: Qi Zheng <[email protected]>
>
> 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 <[email protected]>
> ---
> 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
>

Thanks for the fix Qi Zheng.

Acked-by: Carlos Llamas <[email protected]>

2023-06-26 02:35:44

by Qi Zheng

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

On 2023/6/25 23:49, Qi Zheng wrote:
> From: Qi Zheng <[email protected]>
>
> 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 <[email protected]>

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,

2023-07-21 09:56:52

by Qi Zheng

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

On 2023/6/26 00:16, Carlos Llamas wrote:
> On Sun, Jun 25, 2023 at 03:49:37PM +0000, Qi Zheng wrote:
>> From: Qi Zheng <[email protected]>
>>
>> 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 <[email protected]>
>> ---
>> 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
>>
>
> Thanks for the fix Qi Zheng.
>
> Acked-by: Carlos Llamas <[email protected]>

Hi Greg,

Can this patch be merged? The Fixes tag is:

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

Thanks,
Qi