From 2739b807b0885a09996659be82f813af219c7360 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 11 Jun 2018 08:50:10 +0200 Subject: [PATCH] aio: only return events requested in poll_mask() for IOCB_CMD_POLL The ->poll_mask() operation has a mask of events that the caller is interested in, but not all implementations might take it into account. Mask the return value to only the requested events, similar to what the poll and epoll code does. Reported-by: Avi Kivity Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- fs/aio.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index 134e5b6..e1d2012 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1661,7 +1661,7 @@ static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, if (mask && !(mask & req->events)) return 0; - mask = file->f_op->poll_mask(file, req->events); + mask = file->f_op->poll_mask(file, req->events) & req->events; if (!mask) return 0; @@ -1719,7 +1719,7 @@ static ssize_t aio_poll(struct aio_kiocb *aiocb, struct iocb *iocb) spin_lock_irq(&ctx->ctx_lock); spin_lock(&req->head->lock); - mask = req->file->f_op->poll_mask(req->file, req->events); + mask = req->file->f_op->poll_mask(req->file, req->events) & req->events; if (!mask) { __add_wait_queue(req->head, &req->wait); list_add_tail(&aiocb->ki_list, &ctx->active_reqs); -- 2.7.4