Ack. Agree this is needed for pre-4.14.
On Mon, Feb 26, 2018 at 10:56 AM, Eric Biggers <ebiggers3@xxxxxxxxx> wrote:
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> [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@xxxxxxxxxxxx>
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
> ---
> 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
>