binder: optimize handle generation logic

[PATCH 4/4] binder: fix max_thread type inconsistency

Posted by Carlos Llamas 1 year, 10 months ago

The type defined for the BINDER_SET_MAX_THREADS ioctl was changed from
size_t to __u32 in order to avoid incompatibility issues between 32 and
64-bit kernels. However, the internal types used to copy from user and
store the value were never updated. Use u32 to fix the inconsistency.

Fixes: a9350fc859ae ("staging: android: binder: fix BINDER_SET_MAX_THREADS declaration")
Reported-by: Arve Hjønnevåg <arve@android.com>
Cc: stable@vger.kernel.org
Signed-off-by: Carlos Llamas <cmllamas@google.com>
---
 drivers/android/binder.c          | 2 +-
 drivers/android/binder_internal.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index f120a24c9ae6..2596cbfa16d0 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5408,7 +5408,7 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 			goto err;
 		break;
 	case BINDER_SET_MAX_THREADS: {
-		int max_threads;
+		u32 max_threads;
 
 		if (copy_from_user(&max_threads, ubuf,
 				   sizeof(max_threads))) {
diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h
index 221ab7a6384a..3c522698083f 100644
--- a/drivers/android/binder_internal.h
+++ b/drivers/android/binder_internal.h
@@ -426,7 +426,7 @@ struct binder_proc {
 	struct list_head todo;
 	struct binder_stats stats;
 	struct list_head delivered_death;
-	int max_threads;
+	u32 max_threads;
 	int requested_threads;
 	int requested_threads_started;
 	int tmp_ref;
-- 
2.44.0.683.g7961c838ac-goog

Re: [PATCH 4/4] binder: fix max_thread type inconsistency

Posted by Greg Kroah-Hartman 1 year, 10 months ago

On Wed, Apr 17, 2024 at 07:13:44PM +0000, Carlos Llamas wrote:
> The type defined for the BINDER_SET_MAX_THREADS ioctl was changed from
> size_t to __u32 in order to avoid incompatibility issues between 32 and
> 64-bit kernels. However, the internal types used to copy from user and
> store the value were never updated. Use u32 to fix the inconsistency.
> 
> Fixes: a9350fc859ae ("staging: android: binder: fix BINDER_SET_MAX_THREADS declaration")
> Reported-by: Arve Hjønnevåg <arve@android.com>
> Cc: stable@vger.kernel.org
> Signed-off-by: Carlos Llamas <cmllamas@google.com>
> ---
>  drivers/android/binder.c          | 2 +-
>  drivers/android/binder_internal.h | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)

Why does only patch 4/4 need to go into the tree now, and as a stable
backport, but the first 3 do not?  Shouldn't this be two different
series of patches, one 3 long, and one 1 long, to go to the different
branches (next and linus)?

thanks,

greg k-h

Re: [PATCH 4/4] binder: fix max_thread type inconsistency

Posted by Carlos Llamas 1 year, 9 months ago

On Thu, Apr 18, 2024 at 06:40:52AM +0200, Greg Kroah-Hartman wrote:
> On Wed, Apr 17, 2024 at 07:13:44PM +0000, Carlos Llamas wrote:
> > The type defined for the BINDER_SET_MAX_THREADS ioctl was changed from
> > size_t to __u32 in order to avoid incompatibility issues between 32 and
> > 64-bit kernels. However, the internal types used to copy from user and
> > store the value were never updated. Use u32 to fix the inconsistency.
> > 
> > Fixes: a9350fc859ae ("staging: android: binder: fix BINDER_SET_MAX_THREADS declaration")
> > Reported-by: Arve Hjønnevåg <arve@android.com>
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Carlos Llamas <cmllamas@google.com>
> > ---
> >  drivers/android/binder.c          | 2 +-
> >  drivers/android/binder_internal.h | 2 +-
> >  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> Why does only patch 4/4 need to go into the tree now, and as a stable
> backport, but the first 3 do not?  Shouldn't this be two different
> series of patches, one 3 long, and one 1 long, to go to the different
> branches (next and linus)?

Yes, that is correct. Only patch 4/4 would need to be picked for linus
now and for stable. The others would go to next. Sorry, I was not aware
that sending them separately would be preferred.

I'll drop 4/4 patch from the series in v2. Let me know if you still need
me to send it again separately.

Thanks,
Carlos Llamas

Re: [PATCH 4/4] binder: fix max_thread type inconsistency

Posted by Greg Kroah-Hartman 1 year, 9 months ago

On Sun, Apr 21, 2024 at 12:00:30AM +0000, Carlos Llamas wrote:
> On Thu, Apr 18, 2024 at 06:40:52AM +0200, Greg Kroah-Hartman wrote:
> > On Wed, Apr 17, 2024 at 07:13:44PM +0000, Carlos Llamas wrote:
> > > The type defined for the BINDER_SET_MAX_THREADS ioctl was changed from
> > > size_t to __u32 in order to avoid incompatibility issues between 32 and
> > > 64-bit kernels. However, the internal types used to copy from user and
> > > store the value were never updated. Use u32 to fix the inconsistency.
> > > 
> > > Fixes: a9350fc859ae ("staging: android: binder: fix BINDER_SET_MAX_THREADS declaration")
> > > Reported-by: Arve Hjønnevåg <arve@android.com>
> > > Cc: stable@vger.kernel.org
> > > Signed-off-by: Carlos Llamas <cmllamas@google.com>
> > > ---
> > >  drivers/android/binder.c          | 2 +-
> > >  drivers/android/binder_internal.h | 2 +-
> > >  2 files changed, 2 insertions(+), 2 deletions(-)
> > 
> > Why does only patch 4/4 need to go into the tree now, and as a stable
> > backport, but the first 3 do not?  Shouldn't this be two different
> > series of patches, one 3 long, and one 1 long, to go to the different
> > branches (next and linus)?
> 
> Yes, that is correct. Only patch 4/4 would need to be picked for linus
> now and for stable. The others would go to next. Sorry, I was not aware
> that sending them separately would be preferred.
> 
> I'll drop 4/4 patch from the series in v2. Let me know if you still need
> me to send it again separately.

Please do, thanks!

greg k-h

Re: [PATCH 4/4] binder: fix max_thread type inconsistency

Posted by Carlos Llamas 1 year, 9 months ago

On Sun, Apr 21, 2024 at 08:39:23AM +0200, Greg Kroah-Hartman wrote:
> On Sun, Apr 21, 2024 at 12:00:30AM +0000, Carlos Llamas wrote:
> > On Thu, Apr 18, 2024 at 06:40:52AM +0200, Greg Kroah-Hartman wrote:
> > > On Wed, Apr 17, 2024 at 07:13:44PM +0000, Carlos Llamas wrote:
> > > > The type defined for the BINDER_SET_MAX_THREADS ioctl was changed from
> > > > size_t to __u32 in order to avoid incompatibility issues between 32 and
> > > > 64-bit kernels. However, the internal types used to copy from user and
> > > > store the value were never updated. Use u32 to fix the inconsistency.
> > > > 
> > > > Fixes: a9350fc859ae ("staging: android: binder: fix BINDER_SET_MAX_THREADS declaration")
> > > > Reported-by: Arve Hjønnevåg <arve@android.com>
> > > > Cc: stable@vger.kernel.org
> > > > Signed-off-by: Carlos Llamas <cmllamas@google.com>
> > > > ---
> > > >  drivers/android/binder.c          | 2 +-
> > > >  drivers/android/binder_internal.h | 2 +-
> > > >  2 files changed, 2 insertions(+), 2 deletions(-)
> > > 
> > > Why does only patch 4/4 need to go into the tree now, and as a stable
> > > backport, but the first 3 do not?  Shouldn't this be two different
> > > series of patches, one 3 long, and one 1 long, to go to the different
> > > branches (next and linus)?
> > 
> > Yes, that is correct. Only patch 4/4 would need to be picked for linus
> > now and for stable. The others would go to next. Sorry, I was not aware
> > that sending them separately would be preferred.
> > 
> > I'll drop 4/4 patch from the series in v2. Let me know if you still need
> > me to send it again separately.
> 
> Please do, thanks!
> 
> greg k-h
> 

Ok, done. The separated patch is here:
https://lore.kernel.org/all/20240421173750.3117808-1-cmllamas@google.com/

Thanks,
Carlos Llamas