[PATCH] binder: fix pointer cast warning

[PATCH] binder: fix pointer cast warning

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

binder_uintptr_t is not the same as uintptr_t, so converting it into a
pointer requires a second cast:

drivers/android/binder.c: In function 'binder_translate_fd_array':
drivers/android/binder.c:2511:28: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
 2511 |         sender_ufda_base = (void __user *)sender_uparent->buffer + fda->parent_offset;
      |                            ^

Fixes: 656e01f3ab54 ("binder: read pre-translated fds from sender buffer")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/android/binder.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 5497797ab258..182bb4221b06 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2508,7 +2508,8 @@ static int binder_translate_fd_array(struct list_head *pf_head,
 	 */
 	fda_offset = (parent->buffer - (uintptr_t)t->buffer->user_data) +
 		fda->parent_offset;
-	sender_ufda_base = (void __user *)sender_uparent->buffer + fda->parent_offset;
+	sender_ufda_base = (void __user *)(uintptr_t)sender_uparent->buffer +
+				fda->parent_offset;
 
 	if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32)) ||
 	    !IS_ALIGNED((unsigned long)sender_ufda_base, sizeof(u32))) {
-- 
2.29.2

Re: [PATCH] binder: fix pointer cast warning

[Todd Kjos]

On Tue, Dec 7, 2021 at 4:25 AM Arnd Bergmann <arnd@kernel.org> wrote:
>
> From: Arnd Bergmann <arnd@arndb.de>
>
> binder_uintptr_t is not the same as uintptr_t, so converting it into a
> pointer requires a second cast:
>
> drivers/android/binder.c: In function 'binder_translate_fd_array':
> drivers/android/binder.c:2511:28: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>  2511 |         sender_ufda_base = (void __user *)sender_uparent->buffer + fda->parent_offset;
>       |                            ^
>
> Fixes: 656e01f3ab54 ("binder: read pre-translated fds from sender buffer")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Acked-by: Todd Kjos <tkjos@google.com>

> ---
>  drivers/android/binder.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 5497797ab258..182bb4221b06 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -2508,7 +2508,8 @@ static int binder_translate_fd_array(struct list_head *pf_head,
>          */
>         fda_offset = (parent->buffer - (uintptr_t)t->buffer->user_data) +
>                 fda->parent_offset;
> -       sender_ufda_base = (void __user *)sender_uparent->buffer + fda->parent_offset;
> +       sender_ufda_base = (void __user *)(uintptr_t)sender_uparent->buffer +
> +                               fda->parent_offset;
>
>         if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32)) ||
>             !IS_ALIGNED((unsigned long)sender_ufda_base, sizeof(u32))) {
> --
> 2.29.2
>

Re: [PATCH] binder: fix pointer cast warning

[Christian Brauner]

On Tue, Dec 07, 2021 at 01:24:42PM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> binder_uintptr_t is not the same as uintptr_t, so converting it into a
> pointer requires a second cast:
> 
> drivers/android/binder.c: In function 'binder_translate_fd_array':
> drivers/android/binder.c:2511:28: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>  2511 |         sender_ufda_base = (void __user *)sender_uparent->buffer + fda->parent_offset;
>       |                            ^
> 
> Fixes: 656e01f3ab54 ("binder: read pre-translated fds from sender buffer")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---

Looks good.
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>

Re: [PATCH] binder: fix pointer cast warning

[Randy Dunlap]

On 12/8/21 02:09, Christian Brauner wrote:
> On Tue, Dec 07, 2021 at 01:24:42PM +0100, Arnd Bergmann wrote:
>> From: Arnd Bergmann <arnd@arndb.de>
>>
>> binder_uintptr_t is not the same as uintptr_t, so converting it into a
>> pointer requires a second cast:
>>
>> drivers/android/binder.c: In function 'binder_translate_fd_array':
>> drivers/android/binder.c:2511:28: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>>  2511 |         sender_ufda_base = (void __user *)sender_uparent->buffer + fda->parent_offset;
>>       |                            ^
>>
>> Fixes: 656e01f3ab54 ("binder: read pre-translated fds from sender buffer")
>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>> ---
> 
> Looks good.
> Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
> 

Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested

thanks.

-- 
~Randy