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Date:   Mon, 18 Oct 2021 12:35:23 +0200
From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     Todd Kjos <tkjos@google.com>
Cc:     gregkh@linuxfoundation.org, christian@brauner.io, arve@android.com,
        jannh@google.com, devel@driverdev.osuosl.org,
        linux-kernel@vger.kernel.org, maco@google.com,
        joel@joelfernandes.org, kernel-team@android.com
Subject: Re: [PATCH] binder: don't detect sender/target during buffer cleanup
Message-ID: <20211018103523.dn5rnrefulhd2gzc@wittgenstein>
References: <20211015233811.3532235-1-tkjos@google.com>
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On Fri, Oct 15, 2021 at 04:38:11PM -0700, Todd Kjos wrote:
> When freeing txn buffers, binder_transaction_buffer_release()
> attempts to detect whether the current context is the target by
> comparing current->group_leader to proc->tsk. This is an unreliable
> test. Instead explicitly pass an 'is_failure' boolean.
> 
> Detecting the sender was being used as a way to tell if the
> transaction failed to be sent.  When cleaning up after
> failing to send a transaction, there is no need to close
> the fds associated with a BINDER_TYPE_FDA object. Now
> 'is_failure' can be used to accurately detect this case.
> 
> Fixes: 44d8047f1d87 ("binder: use standard functions to allocate fds")
> Signed-off-by: Todd Kjos <tkjos@google.com>
> ---

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