binder: use wake_up_pollfree()

commit a880b28a71e39013e357fd3adccd1d8a31bc69a8 upstream.

wake_up_poll() uses nr_exclusive=1, so it's not guaranteed to wake up
all exclusive waiters.  Yet, POLLFREE *must* wake up all waiters.  epoll
and aio poll are fortunately not affected by this, but it's very
fragile.  Thus, the new function wake_up_pollfree() has been introduced.

Convert binder to use wake_up_pollfree().

Change-Id: I85d8258f7eceaaabdf1cc84f664abab13b8960cf
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: f5cb779b ("ANDROID: binder: remove waitqueue when thread exits.")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211209010455.42744-3-ebiggers@kernel.org


Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Git-commit: 32288f50
Git-repo: https://android.googlesource.com/kernel/common


Signed-off-by: PavanKumar S.R <quic_pavasr@quicinc.com>