Eric Biggers 8e04c8397b
wait: add wake_up_pollfree() ...
commit 42288cb44c4b5fff7653bc392b583a2b8bd6a8c0 upstream.
Several ->poll() implementations are special in that they use a
waitqueue whose lifetime is the current task, rather than the struct
file as is normally the case. This is okay for blocking polls, since a
blocking poll occurs within one task; however, non-blocking polls
require another solution. This solution is for the queue to be cleared
before it is freed, using 'wake_up_poll(wq, EPOLLHUP | POLLFREE);'.
However, that has a bug: wake_up_poll() calls __wake_up() with
nr_exclusive=1. Therefore, if there are multiple "exclusive" waiters,
and the wakeup function for the first one returns a positive value, only
that one will be called. That's *not* what's needed for POLLFREE;
POLLFREE is special in that it really needs to wake up everyone.
Considering the three non-blocking poll systems:
- io_uring poll doesn't handle POLLFREE at all, so it is broken anyway.
- aio poll is unaffected, since it doesn't support exclusive waits.
However, that's fragile, as someone could add this feature later.
- epoll doesn't appear to be broken by this, since its wakeup function
returns 0 when it sees POLLFREE. But this is fragile.
Although there is a workaround (see epoll), it's better to define a
function which always sends POLLFREE to all waiters. Add such a
function. Also make it verify that the queue really becomes empty after
all waiters have been woken up.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org >
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211209010455.42744-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com >
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org >
2021-12-14 11:32:39 +01:00
2020-09-30 16:37:39 +02:00
2021-04-14 08:42:06 +02:00
2021-04-07 15:00:07 +02:00
2020-10-12 15:29:27 +02:00
2020-08-17 18:54:33 +02:00
2020-10-12 15:29:26 +02:00
2020-07-31 11:49:08 +02:00
2020-10-29 17:22:59 -05:00
2020-09-20 19:01:34 -07:00
2021-05-14 09:50:05 +02:00
2020-10-15 18:42:13 -07:00
2021-05-14 09:50:31 +02:00
2021-07-14 16:56:37 +02:00
2020-10-15 07:57:55 +02:00
2020-08-12 10:57:59 -07:00
2020-10-29 17:22:59 -05:00
2020-08-27 06:55:50 -07:00
2021-08-08 09:05:22 +02:00
2021-06-16 12:01:44 +02:00
2021-10-20 11:45:04 +02:00
2021-05-11 14:47:14 +02:00
2020-10-25 14:51:49 -07:00
2021-03-30 14:32:06 +02:00
2021-04-21 13:00:56 +02:00
2021-04-21 13:00:55 +02:00
2020-08-27 06:55:50 -07:00
2020-09-28 14:53:45 +01:00
2020-09-16 17:38:02 +05:30
2021-11-26 10:39:08 +01:00
2021-09-15 09:50:26 +02:00
2020-10-17 11:18:18 -07:00
2021-03-25 09:04:14 +01:00
2020-07-28 17:11:02 -07:00
2021-12-01 09:19:10 +01:00
2021-08-26 08:35:42 -04:00
2021-03-04 11:38:14 +01:00
2021-09-08 08:49:01 +02:00
2021-09-18 13:40:13 +02:00
2021-11-06 14:10:09 +01:00
2021-03-09 11:11:13 +01:00
2021-12-08 09:03:20 +01:00
2020-09-12 10:45:56 -07:00
2020-09-17 19:21:16 +02:00
2020-10-08 17:17:27 +02:00
2020-10-28 11:13:36 +00:00
2020-09-24 16:44:44 -07:00
2020-07-21 11:12:31 -04:00
2020-09-24 13:43:39 -06:00
2020-07-20 10:27:11 +01:00
2020-08-17 13:47:28 +02:00
2020-10-13 11:37:11 +02:00
2020-07-21 08:24:52 -05:00
2021-07-14 16:56:53 +02:00
2020-08-10 12:16:51 -07:00
2020-10-16 11:11:20 -07:00
2021-06-03 09:00:45 +02:00
2020-10-13 15:05:05 -06:00
2020-10-05 10:47:43 -06:00
2021-01-12 20:18:17 +01:00
2021-11-21 13:46:35 +01:00
2020-11-19 08:55:44 -05:00
2020-08-25 15:00:04 -07:00
2020-08-25 15:00:04 -07:00
2021-08-04 12:46:41 +02:00
2021-08-04 12:46:45 +02:00
2021-09-03 10:09:31 +02:00
2021-12-14 11:32:36 +01:00
2020-07-24 15:41:54 -07:00
2021-03-30 14:32:05 +02:00
2020-09-21 15:00:40 -07:00
2020-10-02 15:00:49 -07:00
2020-08-12 10:57:59 -07:00
2020-12-11 14:02:14 -08:00
2020-10-16 11:11:19 -07:00
2020-10-25 14:51:49 -07:00
2021-09-26 14:08:59 +02:00
2021-11-18 14:04:32 +01:00
2020-08-03 15:07:18 -07:00
2021-07-14 16:56:01 +02:00
2020-09-01 09:19:43 +02:00
2020-10-13 18:38:34 -07:00
2020-10-12 16:44:57 -07:00
2020-10-25 14:51:49 -07:00
2021-07-20 16:05:46 +02:00
2021-07-20 16:05:46 +02:00
2021-07-20 16:05:46 +02:00
2021-09-30 10:11:07 +02:00
2021-05-26 12:06:56 +02:00
2021-11-18 14:03:49 +01:00
2020-08-18 13:45:20 +02:00
2021-06-03 09:00:45 +02:00
2021-05-28 13:17:43 +02:00
2020-09-30 11:50:35 -07:00
2020-10-16 11:11:21 -07:00
2020-09-28 19:47:41 +02:00
2020-09-17 10:19:52 +03:00
2020-10-25 14:51:49 -07:00
2020-11-10 18:31:17 +01:00
2021-05-19 10:13:18 +02:00
2020-10-16 17:21:51 +02:00
2020-10-13 15:58:10 -07:00
2021-09-08 08:49:00 +02:00
2021-03-09 11:11:13 +01:00
2020-10-19 14:28:30 -07:00
2020-09-23 21:29:49 -07:00
2021-06-30 08:47:18 -04:00
2020-10-30 08:37:39 +01:00
2020-09-24 21:56:24 +02:00
2020-08-12 10:57:59 -07:00
2020-09-22 11:27:48 +02:00
2020-07-30 19:26:10 +02:00
2020-09-29 17:50:10 +09:00
2020-10-16 07:28:20 +02:00
2021-03-30 14:32:06 +02:00
2021-08-18 08:59:17 +02:00
2021-01-19 18:27:22 +01:00
2020-09-02 14:39:44 +02:00
2020-10-06 07:07:06 +02:00
2020-09-25 06:12:25 +02:00
2020-07-21 09:42:19 +02:00
2020-10-20 10:41:07 +02:00
2021-05-07 11:04:32 +02:00
2020-07-29 16:14:25 +02:00
2020-09-03 12:21:03 +05:30
2020-07-24 14:33:39 +02:00
2020-10-25 14:51:49 -07:00
2020-08-06 16:13:13 +02:00
2021-03-11 14:17:27 +01:00
2020-09-10 18:19:16 +02:00
2021-03-25 09:04:18 +01:00
2021-05-19 10:13:13 +02:00
2020-07-27 14:29:22 -04:00
2021-10-27 09:56:51 +02:00
2021-09-15 09:50:37 +02:00
2021-03-17 17:06:36 +01:00
2020-07-24 15:03:42 +02:00
2021-11-18 14:04:25 +01:00
2021-09-18 13:40:21 +02:00
2021-03-04 11:38:41 +01:00
2020-10-25 14:51:49 -07:00
2020-08-12 10:57:59 -07:00
2021-04-07 15:00:11 +02:00
2020-09-10 14:03:31 -07:00
2020-07-27 23:24:00 +02:00
2020-10-16 11:11:22 -07:00
2020-08-12 20:42:08 +02:00
2020-09-16 19:27:43 -04:00
2021-11-18 14:03:42 +01:00
2020-10-25 14:51:49 -07:00
2020-10-15 10:46:16 -07:00
2020-08-12 10:57:57 -07:00
2021-07-31 08:16:11 +02:00
2020-09-16 19:12:27 -04:00
2020-07-29 16:14:27 +02:00
2021-11-26 10:39:22 +01:00
2021-09-08 08:48:59 +02:00
2020-12-30 11:54:18 +01:00
2020-07-27 23:24:00 +02:00
2020-07-21 16:02:41 -07:00
2020-10-08 15:29:06 -04:00
2020-08-12 10:57:59 -07:00
2020-11-12 13:59:04 -07:00
2020-10-15 14:43:29 -07:00
2020-07-20 17:00:02 -07:00
2021-12-14 11:32:33 +01:00
2020-08-14 12:52:34 +02:00
2020-08-12 10:57:57 -07:00
2020-10-22 22:44:35 +02:00
2021-06-18 10:00:04 +02:00
2021-09-15 09:50:25 +02:00
2021-07-25 14:36:18 +02:00
2021-09-18 13:40:36 +02:00
2021-09-18 13:40:36 +02:00
2020-08-06 17:54:04 +02:00
2020-09-23 09:42:39 -07:00
2020-09-28 08:55:13 +00:00
2020-09-09 10:22:40 +02:00
2020-09-09 10:38:28 +02:00
2021-05-19 10:12:54 +02:00
2020-07-24 17:12:41 -07:00
2021-03-04 11:38:46 +01:00
2020-09-10 09:32:31 -06:00
2020-10-12 12:08:35 +02:00
2020-10-16 11:11:20 -07:00
2020-09-28 15:07:41 +02:00
2020-09-23 13:24:34 -07:00
2021-03-30 14:31:57 +02:00
2020-08-19 14:02:49 -07:00
2020-10-05 13:37:03 +02:00
2020-09-03 15:17:28 -07:00
2021-08-18 08:59:13 +02:00
2020-08-04 21:02:38 -04:00
2020-10-25 14:51:49 -07:00
2020-10-25 14:51:49 -07:00
2020-07-30 08:22:33 +02:00
2020-07-24 13:56:23 +02:00
2020-08-24 15:09:58 -07:00
2020-10-16 17:35:36 +02:00
2021-09-18 13:40:14 +02:00
2020-09-17 19:21:16 +02:00
2020-09-18 09:13:40 +03:00
2020-09-08 16:28:49 +03:00
2020-10-25 14:51:49 -07:00
2020-11-04 10:22:56 -07:00
2020-08-14 19:56:57 -07:00
2020-08-14 19:56:57 -07:00
2020-07-24 12:42:42 -07:00
2020-09-04 11:16:09 +02:00
2020-10-20 07:10:14 -06:00
2020-11-04 08:52:46 -08:00
2021-05-14 09:50:32 +02:00
2020-09-25 16:30:06 +02:00
2020-10-16 11:11:18 -07:00
2021-12-01 09:19:10 +01:00
2020-09-16 08:54:53 -05:00
2021-03-04 11:38:46 +01:00
2021-08-18 08:59:15 +02:00
2020-07-27 08:55:04 +01:00
2020-11-30 12:21:31 +01:00
2020-08-26 12:41:56 +02:00
2020-10-08 18:00:08 +02:00
2020-11-19 22:38:29 -05:00
2020-10-29 13:17:58 -05:00
2020-10-16 11:11:19 -07:00
2020-10-13 18:38:32 -07:00
2020-08-24 15:09:32 -07:00
2021-01-09 13:46:23 +01:00
2020-10-05 13:37:04 +02:00
2021-11-18 14:03:56 +01:00
2020-09-04 12:46:06 +01:00
2020-10-25 14:51:49 -07:00
2021-03-04 11:37:50 +01:00
2021-03-04 11:37:59 +01:00
2021-03-04 11:38:46 +01:00
2021-03-04 11:38:20 +01:00
2020-07-23 10:33:12 +02:00
2021-12-08 09:03:20 +01:00
2020-09-04 09:25:20 -07:00
2021-02-07 15:37:17 +01:00
2020-08-06 16:13:13 +02:00
2021-06-16 12:01:46 +02:00
2020-07-29 16:14:29 +02:00
2020-07-22 14:41:29 +02:00
2020-08-12 10:57:59 -07:00
2020-07-22 14:42:07 +02:00
2021-11-18 14:03:37 +01:00
2020-07-28 19:29:22 -06:00
2021-02-03 23:28:40 +01:00
2020-07-20 17:59:43 -07:00
2021-09-30 10:11:04 +02:00
2020-10-16 11:11:20 -07:00
2021-09-15 09:50:41 +02:00
2021-09-15 09:50:41 +02:00
2021-09-15 09:50:41 +02:00
2020-09-05 12:14:30 -07:00
2021-11-18 14:03:36 +01:00
2021-11-18 14:03:36 +01:00
2021-04-21 13:01:00 +02:00
2020-10-15 07:49:46 +02:00
2021-10-09 14:40:56 +02:00
2021-07-28 14:35:46 +02:00
2021-08-26 08:35:57 -04:00
2021-09-22 12:27:59 +02:00
2021-03-17 17:06:25 +01:00
2020-08-12 10:57:56 -07:00
2021-03-04 11:38:21 +01:00
2020-09-28 12:16:13 +02:00
2020-10-02 11:33:47 +02:00
2020-09-11 17:41:55 -07:00
2020-08-12 10:58:02 -07:00
2021-06-03 09:00:45 +02:00
2020-08-28 12:37:42 +02:00
2020-08-14 19:56:56 -07:00
2021-06-23 14:42:49 +02:00
2021-06-30 08:47:27 -04:00
2020-09-04 12:46:07 +01:00
2020-10-13 18:38:31 -07:00
2021-06-30 08:47:26 -04:00
2020-08-26 12:41:53 +02:00
2021-03-30 14:32:06 +02:00
2021-08-15 14:00:25 +02:00
2020-07-23 09:12:15 +02:00
2020-10-28 14:08:54 +00:00
2020-10-25 14:51:49 -07:00
2020-08-27 16:06:47 -04:00
2020-09-25 17:48:54 +10:00
2020-07-24 15:41:54 -07:00
2020-07-24 15:41:54 -07:00
2021-08-18 08:59:17 +02:00
2021-03-30 14:32:07 +02:00
2020-10-05 18:40:01 -07:00
2021-07-19 09:44:51 +02:00
2021-12-08 09:03:25 +01:00
2020-10-30 12:57:39 +01:00
2020-10-30 12:57:39 +01:00
2020-07-24 15:41:54 -07:00
2020-10-21 18:24:08 -07:00
2020-10-07 14:28:39 -04:00
2020-10-07 14:28:39 -04:00
2021-11-18 14:04:23 +01:00
2020-11-30 10:52:22 -05:00
2020-10-21 10:31:20 -04:00
2021-05-19 10:13:02 +02:00
2020-09-22 13:58:40 +02:00
2020-10-16 11:11:18 -07:00
2020-10-16 11:11:19 -07:00
2020-07-21 10:50:36 +01:00
2020-09-01 09:58:03 +02:00
2020-11-22 10:48:22 -08:00
2020-07-29 07:45:20 +02:00
2021-02-07 15:37:16 +01:00
2020-07-29 17:12:08 +02:00
2020-07-29 17:12:08 +02:00
2020-10-25 14:51:49 -07:00
2020-07-28 22:49:52 +02:00
2020-07-28 15:51:32 +01:00
2020-07-28 15:51:32 +01:00
2020-07-28 15:51:32 +01:00
2021-07-19 09:44:39 +02:00
2021-03-09 11:11:13 +01:00
2020-09-25 17:48:54 +10:00
2021-09-03 10:09:21 +02:00
2020-10-13 18:38:35 -07:00
2020-10-17 11:18:18 -07:00
2020-07-23 17:34:18 +10:00
2020-10-16 11:11:15 -07:00
2020-09-25 18:01:48 -04:00
2020-10-16 11:11:16 -07:00
2020-08-07 11:33:29 -07:00
2021-06-30 08:47:29 -04:00
2021-09-22 12:28:00 +02:00
2020-07-24 09:50:41 -05:00
2020-09-17 12:27:43 -05:00
2020-09-17 16:44:03 -05:00
2021-05-19 10:13:01 +02:00
2021-05-19 10:13:01 +02:00
2021-11-21 13:46:36 +01:00
2020-08-31 12:52:33 -07:00
2020-09-11 09:30:01 +03:00
2020-08-07 11:33:26 -07:00
2020-10-25 14:51:49 -07:00
2020-10-06 07:29:36 -06:00
2020-09-16 16:26:56 +02:00
2021-11-26 10:39:22 +01:00
2020-11-09 18:12:34 +01:00
2021-03-17 17:06:28 +01:00
2021-03-30 14:32:05 +02:00
2020-08-31 12:52:33 -07:00
2020-10-18 09:27:10 -07:00
2021-09-03 10:09:28 +02:00
2021-05-14 09:50:14 +02:00
2020-07-28 17:07:06 -07:00
2020-10-16 17:53:22 +02:00
2020-08-04 12:44:53 +02:00
2021-05-14 09:50:16 +02:00
2021-05-19 10:12:51 +02:00
2020-08-12 10:57:59 -07:00
2021-11-18 14:04:29 +01:00
2020-08-26 16:53:26 +02:00
2020-09-10 19:27:59 +02:00
2021-07-14 16:55:58 +02:00
2020-09-14 09:45:34 -07:00
2020-10-25 14:51:49 -07:00
2020-12-30 11:53:56 +01:00
2020-10-14 16:09:32 -07:00
2020-09-11 21:47:10 -07:00
2020-09-22 17:50:32 +02:00
2020-09-27 13:29:49 -07:00
2021-06-23 14:42:45 +02:00
2020-07-21 10:50:37 +01:00
2020-08-26 20:15:34 +01:00
2020-09-14 15:45:25 +02:00
2021-04-07 15:00:13 +02:00
2020-09-17 13:00:46 -04:00
2020-10-13 08:41:26 -04:00
2020-08-03 23:24:26 -07:00
2020-10-13 18:38:28 -07:00
2020-07-27 17:46:24 +09:00
2020-07-27 17:46:24 +09:00
2020-09-10 11:19:29 +02:00
2020-08-24 18:36:09 -07:00
2020-09-23 19:32:09 -07:00
2021-09-18 13:40:19 +02:00
2020-08-24 18:37:56 -07:00
2020-08-24 18:37:56 -07:00
2020-10-28 11:41:15 -06:00
2020-10-05 18:35:30 +01:00
2020-07-27 14:31:13 -04:00
2020-10-13 19:20:54 -05:00
2020-08-18 17:06:15 +02:00
2020-07-28 17:09:49 -07:00
2021-06-30 08:47:27 -04:00
2020-10-04 19:51:43 -07:00
2021-11-18 14:04:22 +01:00
2020-07-22 13:39:31 +02:00
2021-01-09 13:46:24 +01:00
2020-10-05 20:45:45 -03:00
2020-07-20 11:50:47 +01:00
2021-10-17 10:43:33 +02:00
2020-09-14 07:31:03 +01:00
2020-08-04 21:00:11 -07:00
2021-11-18 14:03:36 +01:00
2020-08-18 13:45:20 +02:00
2020-12-30 11:53:42 +01:00
2021-11-18 14:04:27 +01:00
2021-03-17 17:06:34 +01:00
2020-07-29 17:14:38 +02:00
2020-10-25 14:51:49 -07:00
2020-08-07 11:33:24 -07:00
2020-10-29 13:17:58 -05:00
2021-12-08 09:03:23 +01:00
2021-09-22 12:27:58 +02:00
2021-08-04 12:46:44 +02:00
2020-08-07 11:33:25 -07:00
2020-10-25 11:39:02 -07:00
2020-08-07 11:33:25 -07:00
2020-09-04 11:50:50 -07:00
2021-05-14 09:50:46 +02:00
2020-09-30 11:50:35 -07:00
2021-06-23 14:42:44 +02:00
2020-08-10 12:06:44 -07:00
2020-10-25 14:51:49 -07:00
2020-10-22 14:15:51 -06:00
2021-09-03 10:09:30 +02:00
2021-09-03 10:09:30 +02:00
2020-09-19 13:13:39 -07:00
2020-09-18 14:24:16 +01:00
2020-09-26 22:55:05 -04:00
2020-09-18 16:45:50 -04:00
2021-03-30 14:31:53 +02:00
2021-03-30 14:31:53 +02:00
2021-09-03 10:09:25 +02:00
2021-03-17 17:06:34 +01:00
2020-09-30 10:50:30 +02:00
2020-10-06 11:18:04 +02:00
2020-09-23 10:43:19 -06:00
2020-10-13 18:38:30 -07:00
2021-07-25 14:36:17 +02:00
2021-07-25 14:36:18 +02:00
2021-05-07 11:04:32 +02:00
2021-01-17 14:16:59 +01:00
2020-08-14 19:56:56 -07:00
2020-10-02 12:02:30 +02:00
2020-10-17 15:05:30 -06:00
2020-07-27 14:11:22 +02:00
2020-09-10 13:15:40 -07:00
2021-08-15 14:00:24 +02:00
2021-09-26 14:08:59 +02:00
2021-03-25 09:04:16 +01:00
2021-09-16 12:51:23 +02:00
2020-08-06 16:13:13 +02:00
2020-08-23 10:38:24 +02:00
2020-09-24 22:12:18 +02:00
2020-09-16 22:05:18 +10:00
2020-07-24 08:16:01 +03:00
2021-11-18 14:04:11 +01:00
2021-11-26 10:39:14 +01:00
2020-12-30 11:53:42 +01:00
2020-10-05 12:43:53 +02:00
2020-10-17 15:04:36 -06:00
2020-10-15 15:51:28 -07:00
2021-07-14 16:55:46 +02:00
2021-05-14 09:50:18 +02:00
2021-03-04 11:37:36 +01:00
2021-05-14 09:50:18 +02:00
2020-07-29 16:14:18 +02:00
2021-03-30 14:31:51 +02:00
2020-09-17 19:21:16 +02:00
2020-10-24 10:57:57 -07:00
2021-05-14 09:50:31 +02:00
2021-02-17 11:02:28 +01:00
2020-09-10 14:03:31 -07:00
2021-03-25 09:04:14 +01:00
2021-03-17 17:06:19 +01:00
2021-09-08 08:49:00 +02:00
2021-03-30 14:32:03 +02:00
2020-07-20 15:04:32 +02:00
2020-10-23 11:55:27 -04:00
2020-08-01 11:28:17 +02:00
2020-09-08 13:33:11 +02:00
2020-08-06 16:13:13 +02:00
2020-08-05 11:08:41 -04:00
2020-10-23 11:00:57 -07:00
2020-08-18 10:01:44 +02:00
2021-11-26 10:39:16 +01:00
2020-08-05 09:30:19 -04:00
2021-08-26 08:35:41 -04:00
2020-09-04 09:31:54 -07:00
2021-02-10 09:29:21 +01:00
2020-10-16 11:11:19 -07:00
2020-10-05 13:21:49 +02:00
2021-12-14 11:32:39 +01:00
2020-10-01 09:40:35 -04:00
2020-08-05 18:43:02 +02:00
2020-08-12 10:57:59 -07:00
2021-04-07 15:00:06 +02:00
2020-10-20 14:39:37 -07:00
2020-08-09 13:58:04 -07:00
2020-08-12 10:57:59 -07:00
2020-08-12 10:57:59 -07:00
2020-08-12 10:57:59 -07:00
2021-03-07 12:34:15 +01:00
8e04c8397b