Re: [PATCH] binder: Remove bogus warning on failed same-process transaction

[Christian Brauner]

On Thu, Aug 06, 2020 at 06:53:59PM +0200, Jann Horn wrote:
> While binder transactions with the same binder_proc as sender and recipient
> are forbidden, transactions with the same task_struct as sender and
> recipient are possible (even though currently there is a weird check in
> binder_transaction() that rejects them in the target==0 case).
> Therefore, task_struct identities can't be used to distinguish whether
> the caller is running in the context of the sender or the recipient.
> 
> Since I see no easy way to make this WARN_ON() useful and correct, let's
> just remove it.
> 
> Fixes: 44d8047f1d87 ("binder: use standard functions to allocate fds")
> Reported-by: syzbot+e113a0b970b7b3f394ba@xxxxxxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Jann Horn <jannh@xxxxxxxxxx>
> ---

Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx>

Thanks!
Christian