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Date: Mon, 26 Feb 2018 20:37:09 +0100
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Eric Biggers <ebiggers3@gmail.com>
Cc: stable@vger.kernel.org, Guenter Roeck <linux@roeck-us.net>,
        Todd Kjos <tkjos@android.com>,
        Eric Biggers <ebiggers@google.com>
Subject: Re: [PATCH 4.4,4.9] binder: add missing binder_unlock()
Message-ID: <20180226193709.GC21453@kroah.com>
References: <20180226185645.241652-1-ebiggers3@gmail.com>
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On Mon, Feb 26, 2018 at 10:56:45AM -0800, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@google.com>
> 
> [Please apply to 4.4-stable and 4.9-stable.]
> 
> When commit 4be5a2810489 ("binder: check for binder_thread allocation
> failure in binder_poll()") was applied to 4.4-stable and 4.9-stable it
> was forgotten to release the global binder lock in the new error path.
> The global binder lock wasn't removed until v4.14, by commit
> a60b890f607d ("binder: remove global binder lock").
> 
> Fix the new error path to release the lock.
> 
> Reported-by: Guenter Roeck <linux@roeck-us.net>
> Signed-off-by: Eric Biggers <ebiggers@google.com>
> ---
>  drivers/android/binder.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 3b6ac80b2127..49199bd2ab93 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -2628,8 +2628,10 @@ static unsigned int binder_poll(struct file *filp,
>  	binder_lock(__func__);
>  
>  	thread = binder_get_thread(proc);
> -	if (!thread)
> +	if (!thread) {
> +		binder_unlock(__func__);
>  		return POLLERR;
> +	}
>  
>  	wait_for_proc_work = thread->transaction_stack == NULL &&
>  		list_empty(&thread->todo) && thread->return_error == BR_OK;
> -- 
> 2.16.1.291.g4437f3f132-goog

Thanks for the patch, all now queued up.

greg k-h