diff options
| author | Jens Axboe <axboe@kernel.dk> | 2022-04-08 11:08:58 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-13 20:03:20 +0200 |
| commit | d568c13d9d29d3151540a0d1b20c3a1ca801a662 (patch) | |
| tree | b26928840a463b9da28428d48b87590b9098b5c8 | |
| parent | ed6b5cb53a22189ffb0dcc0b0ad34b256653909d (diff) | |
io_uring: fix race between timeout flush and removal
commit e677edbcabee849bfdd43f1602bccbecf736a646 upstream.
io_flush_timeouts() assumes the timeout isn't in progress of triggering
or being removed/canceled, so it unconditionally removes it from the
timeout list and attempts to cancel it.
Leave it on the list and let the normal timeout cancelation take care
of it.
Cc: stable@vger.kernel.org # 5.5+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/io_uring.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 13001cd22bba..4eb858162559 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1614,12 +1614,11 @@ static __cold void io_flush_timeouts(struct io_ring_ctx *ctx) __must_hold(&ctx->completion_lock) { u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts); + struct io_kiocb *req, *tmp; spin_lock_irq(&ctx->timeout_lock); - while (!list_empty(&ctx->timeout_list)) { + list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) { u32 events_needed, events_got; - struct io_kiocb *req = list_first_entry(&ctx->timeout_list, - struct io_kiocb, timeout.list); if (io_is_timeout_noseq(req)) break; @@ -1636,7 +1635,6 @@ static __cold void io_flush_timeouts(struct io_ring_ctx *ctx) if (events_got < events_needed) break; - list_del_init(&req->timeout.list); io_kill_timeout(req, 0); } ctx->cq_last_tm_flush = seq; @@ -6223,6 +6221,7 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, if (data->ts.tv_sec < 0 || data->ts.tv_nsec < 0) return -EINVAL; + INIT_LIST_HEAD(&req->timeout.list); data->mode = io_translate_timeout_mode(flags); hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode); |