1665 Commits

Author SHA1 Message Date
Pavel Begunkov
98aada6e22 io_uring/rw: fix unexpected link breakage
[ upstream commit bf68b5b34311ee57ed40749a1257a30b46127556 ]

req->cqe.res is set in io_read() to the amount of bytes left to be done,
which is used to figure out whether to fail a read or not. However,
io_read() may do another without returning, and we stash the previous
value into ->bytes_done but forget to update cqe.res. Then we ask a read
to do strictly less than cqe.res but expect the return to be exactly
cqe.res.

Fix the bug by updating cqe.res for retries.

Cc: stable@vger.kernel.org
Reported-and-Tested-by: Beld Zhang <beldzhang@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3a1088440c7be98e5800267af922a67da0ef9f13.1664235732.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:35:53 +02:00
Pavel Begunkov
d6b7efc722 io_uring/rw: fix error'ed retry return values
[ upstream commit 62bb0647b14646fa6c9aa25ecdf67ad18f13523c ]

Kernel test robot reports that we test negativity of an unsigned in
io_fixup_rw_res() after a recent change, which masks error codes and
messes up the return value in case I/O is re-retried and failed with
an error.

Fixes: 4d9cb92ca41dd ("io_uring/rw: fix short rw error handling")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9754a0970af1861e7865f9014f735c70dc60bf79.1663071587.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:35:53 +02:00
Pavel Begunkov
e857457c6f io_uring/rw: fix short rw error handling
[ upstream commit 89473c1a9205760c4fa6d158058da7b594a815f0 ]

We have a couple of problems, first reports of unexpected link breakage
for reads when cqe->res indicates that the IO was done in full. The
reason here is partial IO with retries.

TL;DR; we compare the result in __io_complete_rw_common() against
req->cqe.res, but req->cqe.res doesn't store the full length but rather
the length left to be done. So, when we pass the full corrected result
via kiocb_done() -> __io_complete_rw_common(), it fails.

The second problem is that we don't try to correct res in
io_complete_rw(), which, for instance, might be a problem for O_DIRECT
but when a prefix of data was cached in the page cache. We also
definitely don't want to pass a corrected result into io_rw_done().

The fix here is to leave __io_complete_rw_common() alone, always pass
not corrected result into it and fix it up as the last step just before
actually finishing the I/O.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:35:53 +02:00
Pavel Begunkov
cd148d4e31 io_uring: correct pinned_vm accounting
[ upstream commit 42b6419d0aba47c5d8644cdc0b68502254671de5 ]

->mm_account should be released only after we free all registered
buffers, otherwise __io_sqe_buffers_unregister() will see a NULL
->mm_account and skip locked_vm accounting.

Cc: <Stable@vger.kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6d798f65ed4ab8db3664c4d3397d4af16ca98846.1664849932.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:35:52 +02:00
Pavel Begunkov
813d8fe5d3 io_uring/af_unix: defer registered files gc to io_uring release
[ upstream commit 0091bfc81741b8d3aeb3b7ab8636f911b2de6e80 ]

Instead of putting io_uring's registered files in unix_gc() we want it
to be done by io_uring itself. The trick here is to consider io_uring
registered files for cycle detection but not actually putting them down.
Because io_uring can't register other ring instances, this will remove
all refs to the ring file triggering the ->release path and clean up
with io_ring_ctx_free().

Cc: stable@vger.kernel.org
Fixes: 6b06314c47e1 ("io_uring: add file set registration")
Reported-and-tested-by: David Bouman <dbouman03@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
[axboe: add kerneldoc comment to skb, fold in skb leak fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:35:52 +02:00
Pavel Begunkov
f9dc33f231 io_uring/net: don't update msg_name if not provided
commit 6f10ae8a155446248055c7ddd480ef40139af788 upstream.

io_sendmsg_copy_hdr() may clear msg->msg_name if the userspace didn't
provide it, we should retain NULL in this case.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/97d49f61b5ec76d0900df658cfde3aa59ff22121.1664486545.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:34:18 +02:00
Pavel Begunkov
e9d7ca0c46 io_uring: fix UAF due to missing POLLFREE handling
[ upstream commmit 791f3465c4afde02d7f16cf7424ca87070b69396 ]

Fixes a problem described in 50252e4b5e989
("aio: fix use-after-free due to missing POLLFREE handling")
and copies the approach used there.

In short, we have to forcibly eject a poll entry when we meet POLLFREE.
We can't rely on io_poll_get_ownership() as can't wait for potentially
running tw handlers, so we use the fact that wqs are RCU freed. See
Eric's patch and comments for more details.

Reported-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20211209010455.42744-6-ebiggers@kernel.org
Reported-and-tested-by: syzbot+5426c7ed6868c705ca14@syzkaller.appspotmail.com
Fixes: 221c5eb233823 ("io_uring: add support for IORING_OP_POLL")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/4ed56b6f548f7ea337603a82315750449412748a.1642161259.git.asml.silence@gmail.com
[axboe: drop non-functional change from patch]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:06 +02:00
Pavel Begunkov
182dc3aa5a io_uring: fix wrong arm_poll error handling
[ upstream commmit 9d2ad2947a53abf5e5e6527a9eeed50a3a4cbc72 ]

Leaving ip.error set when a request was punted to task_work execution is
problematic, don't forget to clear it.

Fixes: aa43477b04025 ("io_uring: poll rework")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a6c84ef4182c6962380aebe11b35bdcb25b0ccfb.1655852245.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:06 +02:00
Pavel Begunkov
6c7259c837 io_uring: fail links when poll fails
[ upstream commmit c487a5ad48831afa6784b368ec40d0ee50f2fe1b ]

Don't forget to cancel all linked requests of poll request when
__io_arm_poll_handler() failed.

Fixes: aa43477b04025 ("io_uring: poll rework")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a78aad962460f9fdfe4aa4c0b62425c88f9415bc.1655852245.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:05 +02:00
Jens Axboe
c41e79a0c4 io_uring: bump poll refs to full 31-bits
[ upstream commmit e2c0cb7c0cc72939b61a7efee376206725796625 ]

The previous commit:

1bc84c40088 ("io_uring: remove poll entry from list when canceling all")

removed a potential overflow condition for the poll references. They
are currently limited to 20-bits, even if we have 31-bits available. The
upper bit is used to mark for cancelation.

Bump the poll ref space to 31-bits, making that kind of situation much
harder to trigger in general. We'll separately add overflow checking
and handling.

Fixes: aa43477b0402 ("io_uring: poll rework")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:05 +02:00
Jens Axboe
7524ec52ca io_uring: remove poll entry from list when canceling all
[ upstream commmit 61bc84c4008812d784c398cfb54118c1ba396dfc ]

When the ring is exiting, as part of the shutdown, poll requests are
removed. But io_poll_remove_all() does not remove entries when finding
them, and since completions are done out-of-band, we can find and remove
the same entry multiple times.

We do guard the poll execution by poll ownership, but that does not
exclude us from reissuing a new one once the previous removal ownership
goes away.

This can race with poll execution as well, where we then end up seeing
req->apoll be NULL because a previous task_work requeue finished the
request.

Remove the poll entry when we find it and get ownership of it. This
prevents multiple invocations from finding it.

Fixes: aa43477b0402 ("io_uring: poll rework")
Reported-by: Dylan Yudaken <dylany@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:05 +02:00
Jiapeng Chong
95a004a223 io_uring: Remove unused function req_ref_put
[ upstream commmit c84b8a3fef663933007e885535591b9d30bdc860 ]

Fix the following clang warnings:

fs/io_uring.c:1195:20: warning: unused function 'req_ref_put'
[-Wunused-function].

Fixes: aa43477b0402 ("io_uring: poll rework")
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220113162005.3011-1-jiapeng.chong@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:05 +02:00
Pavel Begunkov
f770fba096 io_uring: poll rework
[ upstream commmit aa43477b040251f451db0d844073ac00a8ab66ee ]

It's not possible to go forward with the current state of io_uring
polling, we need a more straightforward and easier synchronisation.
There are a lot of problems with how it is at the moment, including
missing events on rewait.

The main idea here is to introduce a notion of request ownership while
polling, no one but the owner can modify any part but ->poll_refs of
struct io_kiocb, that grants us protection against all sorts of races.

Main users of such exclusivity are poll task_work handler, so before
queueing a tw one should have/acquire ownership, which will be handed
off to the tw handler.
The other user is __io_arm_poll_handler() do initial poll arming. It
starts taking the ownership, so tw handlers won't be run until it's
released later in the function after vfs_poll. note: also prevents
races in __io_queue_proc().
Poll wake/etc. may not be able to get ownership, then they need to
increase the poll refcount and the task_work should notice it and retry
if necessary, see io_poll_check_events().
There is also IO_POLL_CANCEL_FLAG flag to notify that we want to kill
request.

It makes cancellations more reliable, enables double multishot polling,
fixes double poll rewait, fixes missing poll events and fixes another
bunch of races.

Even though it adds some overhead for new refcounting, and there are a
couple of nice performance wins:
- no req->refs refcounting for poll requests anymore
- if the data is already there (once measured for some test to be 1-2%
  of all apoll requests), it removes it doesn't add atomics and removes
  spin_lock/unlock pair.
- works well with multishots, we don't do remove from queue / add to
  queue for each new poll event.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6b652927c77ed9580ea4330ac5612f0e0848c946.1639605189.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:05 +02:00
Pavel Begunkov
8dc669632f io_uring: inline io_poll_complete
[ upstream commmit eb6e6f0690c846f7de46181bab3954c12c96e11e ]

Inline io_poll_complete(), it's simple and doesn't have any particular
purpose.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/933d7ee3e4450749a2d892235462c8f18d030293.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:05 +02:00
Pavel Begunkov
20bbcc3163 io_uring: kill poll linking optimisation
[ upstream commmit ab1dab960b8352cee082db0f8a54dc92a948bfd7 ]

With IORING_FEAT_FAST_POLL in place, io_put_req_find_next() for poll
requests doesn't make much sense, and in any case re-adding it
shouldn't be a problem considering batching in tctx_task_work(). We can
remove it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/15699682bf81610ec901d4e79d6da64baa9f70be.1639605189.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:05 +02:00
Pavel Begunkov
a85d7ac14f io_uring: move common poll bits
[ upstream commmit 5641897a5e8fb8abeb07e89c71a788d3db3ec75e ]

Move some poll helpers/etc up, we'll need them there shortly

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6c5c3dba24c86aad5cd389a54a8c7412e6a0621d.1639605189.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:04 +02:00
Pavel Begunkov
040e58f51c io_uring: refactor poll update
[ upstream commmit 2bbb146d96f4b45e17d6aeede300796bc1a96d68 ]

Clean up io_poll_update() and unify cancellation paths for remove and
update.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5937138b6265a1285220e2fab1b28132c1d73ce3.1639605189.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:04 +02:00
Pavel Begunkov
b850d6ddc7 io_uring: clean cqe filling functions
[ upstream commmit 913a571affedd17239c4d4ea90c8874b32fc2191 ]

Split io_cqring_fill_event() into a couple of more targeted functions.
The first on is io_fill_cqe_aux() for completions that are not
associated with request completions and doing the ->cq_extra accounting.
Examples are additional CQEs from multishot poll and rsrc notifications.

The second is io_fill_cqe_req(), should be called when it's a normal
request completion. Nothing more to it at the moment, will be used in
later patches.

The last one is inlined __io_fill_cqe() for a finer grained control,
should be used with caution and in hottest places.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/59a9117a4a44fc9efcf04b3afa51e0d080f5943c.1636559119.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:04 +02:00
Pavel Begunkov
5c0ea4c8e5 io_uring: correct fill events helpers types
[ upstream commit 54daa9b2d80ab35824464b35a99f716e1cdf2ccb ]

CQE result is a 32-bit integer, so the functions generating CQEs are
better to accept not long but ints. Convert io_cqring_fill_event() and
other helpers.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7ca6f15255e9117eae28adcac272744cae29b113.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[pavel: backport]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:04 +02:00
Jens Axboe
295219ab7d io_uring: fix issue with io_write() not always undoing sb_start_write()
commit e053aaf4da56cbf0afb33a0fda4a62188e2c0637 upstream.

This is actually an older issue, but we never used to hit the -EAGAIN
path before having done sb_start_write(). Make sure that we always call
kiocb_end_write() if we need to retry the write, so that we keep the
calls to sb_start_write() etc balanced.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-31 17:16:49 +02:00
Jens Axboe
3746d62ecf io_uring: use original request task for inflight tracking
commit 386e4fb6962b9f248a80f8870aea0870ca603e89 upstream.

In prior kernels, we did file assignment always at prep time. This meant
that req->task == current. But after deferring that assignment and then
pushing the inflight tracking back in, we've got the inflight tracking
using current when it should in fact now be using req->task.

Fixup that error introduced by adding the inflight tracking back after
file assignments got modifed.

Fixes: 9cae36a094e7 ("io_uring: reinstate the inflight tracking")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21 15:17:47 +02:00
Pavel Begunkov
fa3040688d io_uring: mem-account pbuf buckets
commit cc18cc5e82033d406f54144ad6f8092206004684 upstream.

Potentially, someone may create as many pbuf bucket as there are indexes
in an xarray without any other restrictions bounding our memory usage,
put memory needed for the buckets under memory accounting.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d34c452e45793e978d26e2606211ec9070d329ea.1659622312.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-17 14:24:31 +02:00
Pavel Begunkov
51ebf1b6a0 io_uring: avoid io-wq -EAGAIN looping for !IOPOLL
[ Upstream commit e0deb6a025ae8c850dc8685be39fb27b06c88736 ]

If an opcode handler semi-reliably returns -EAGAIN, io_wq_submit_work()
might continue busily hammer the same handler over and over again, which
is not ideal. The -EAGAIN handling in question was put there only for
IOPOLL, so restrict it to IOPOLL mode only where there is no other
recourse than to retry as we cannot wait.

Fixes: def596e9557c9 ("io_uring: support for IO polling")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f168b4f24181942f3614dd8ff648221736f572e6.1652433740.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-12 16:35:08 +02:00
Jens Axboe
df1ec53252 io_uring: ensure that fsnotify is always called
[ Upstream commit f63cf5192fe3418ad5ae1a4412eba5694b145f79 ]

Ensure that we call fsnotify_modify() if we write a file, and that we
do fsnotify_access() if we read it. This enables anyone using inotify
on the file to get notified.

Ditto for fallocate, ensure that fsnotify_modify() is called.

Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-12 16:34:57 +02:00
Jens Axboe
50fefe57f4 io_uring: ensure that send/sendmsg and recv/recvmsg check sqe->ioprio
commit 73911426aaaadbae54fa72359b33a7b6a56947db upstream.

All other opcodes correctly check if this is set and -EINVAL if it is
and they don't support that field, for some reason the these were
forgotten.

This was unified a bit differently in the upstream tree, but had the
same effect as making sure we error on this field. Rather than have
a painful backport of the upstream commit, just fixup the mentioned
opcodes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:53:28 +02:00
Pavel Begunkov
ea512d540a io_uring: fix not locked access to fixed buf table
commit 05b538c1765f8d14a71ccf5f85258dcbeaf189f7 upstream.

We can look inside the fixed buffer table only while holding
->uring_lock, however in some cases we don't do the right async prep for
IORING_OP_{WRITE,READ}_FIXED ending up with NULL req->imu forcing making
an io-wq worker to try to resolve the fixed buffer without proper
locking.

Move req->imu setup into early req init paths, i.e. io_prep_rw(), which
is called unconditionally for rw requests and under uring_lock.

Fixes: 634d00df5e1cf ("io_uring: add full-fledged dynamic buffers support")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-02 16:41:18 +02:00
Pavel Begunkov
91f5a60a83 io_uring: fix races with buffer table unregister
[ Upstream commit d11d31fc5d8a96f707facee0babdcffaafa38de2 ]

Fixed buffer table quiesce might unlock ->uring_lock, potentially
letting new requests to be submitted, don't allow those requests to
use the table as they will race with unregistration.

Reported-and-tested-by: van fantasy <g1042620637@gmail.com>
Fixes: bd54b6fe3316ec ("io_uring: implement fixed buffers registration similar to fixed files")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-22 14:22:00 +02:00
Pavel Begunkov
b1e7cade3c io_uring: fix races with file table unregister
[ Upstream commit b0380bf6dad4601d92025841e2b7a135d566c6e3 ]

Fixed file table quiesce might unlock ->uring_lock, potentially letting
new requests to be submitted, don't allow those requests to use the
table as they will race with unregistration.

Reported-and-tested-by: van fantasy <g1042620637@gmail.com>
Fixes: 05f3fb3c53975 ("io_uring: avoid ring quiesce for fixed file set unregister and update")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-22 14:22:00 +02:00
Pavel Begunkov
5655455a06 io_uring: arm poll for non-nowait files
commit e74ead135bc4459f7d40b1f8edab1333a28b54e8 upstream.

Don't check if we can do nowait before arming apoll, there are several
reasons for that. First, we don't care much about files that don't
support nowait. Second, it may be useful -- we don't want to be taking
away extra workers from io-wq when it can go in some async. Even if it
will go through io-wq eventually, it make difference in the numbers of
workers actually used. And the last one, it's needed to clean nowait in
future commits.

[kernel test robot: fix unused-var]

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9d06f3cb2c8b686d970269a87986f154edb83043.1634425438.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-25 09:57:21 +02:00
Jens Axboe
37811e46a2 io_uring: check reserved fields for recv/recvmsg
[ Upstream commit 5a1e99b61b0c81388cde0c808b3e4173907df19f ]

We should check unused fields for non-zero and -EINVAL if they are set,
making it consistent with other opcodes.

Fixes: aa1fa28fc73e ("io_uring: add support for recvmsg()")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-09 09:14:38 +02:00
Jens Axboe
79c10cb188 io_uring: check reserved fields for send/sendmsg
[ Upstream commit 588faa1ea5eecb351100ee5d187b9be99210f70d ]

We should check unused fields for non-zero and -EINVAL if they are set,
making it consistent with other opcodes.

Fixes: 0fa03c624d8f ("io_uring: add support for sendmsg()")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-09 09:14:38 +02:00
Pavel Begunkov
b8ed0f7531 io_uring: use nospec annotation for more indexes
[ Upstream commit 4cdd158be9d09223737df83136a1fb65269d809a ]

There are still several places that using pre array_index_nospec()
indexes, fix them up.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b01ef5ee83f72ed35ad525912370b729f5d145f4.1649336342.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:34:17 +02:00
Pavel Begunkov
5218d5cc02 io_uring: zero tag on rsrc removal
[ Upstream commit 8f0a24801bb44aa58496945aabb904c729176772 ]

Automatically default rsrc tag in io_queue_rsrc_removal(), it's safer
than leaving it there and relying on the rest of the code to behave and
not use it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1cf262a50df17478ea25b22494dcc19f3a80301f.1649336342.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:34:17 +02:00
Dylan Yudaken
9947548d9c io_uring: verify pad field is 0 in io_get_ext_arg
[ Upstream commit d2347b9695dafe5c388a5f9aeb70e27a7a4d29cf ]

Ensure that only 0 is passed for pad here.

Fixes: c73ebb685fb6 ("io_uring: add timeout support for io_uring_enter()")
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220412163042.2788062-5-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:34:12 +02:00
Dylan Yudaken
7a7c9f9de9 io_uring: verify that resv2 is 0 in io_uring_rsrc_update2
[ Upstream commit d8a3ba9c143bf89c032deced8a686ffa53b46098 ]

Verify that the user does not pass in anything but 0 for this field.

Fixes: 992da01aa932 ("io_uring: change registration/upd/rsrc tagging ABI")
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220412163042.2788062-3-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:34:12 +02:00
Dylan Yudaken
22aa1597f4 io_uring: move io_uring_rsrc_update2 validation
[ Upstream commit 565c5e616e8061b40a2e1d786c418a7ac3503a8d ]

Move validation to be more consistently straight after
copy_from_user. This is already done in io_register_rsrc_update and so
this removes that redundant check.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220412163042.2788062-2-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:34:12 +02:00
Jens Axboe
ba7261af2b 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>
2022-04-13 20:59:22 +02:00
Eugene Syromiatnikov
fe223dd2f1 io_uring: implement compat handling for IORING_REGISTER_IOWQ_AFF
commit 0f5e4b83b37a96e3643951588ed7176b9b187c0a upstream.

Similarly to the way it is done im mbind syscall.

Cc: stable@vger.kernel.org # 5.14
Fixes: fe76421d1da1dcdb ("io_uring: allow user configurable IO thread CPU affinity")
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-13 20:59:22 +02:00
Jens Axboe
ae6cba337c io_uring: defer splice/tee file validity check until command issue
commit a3e4bc23d5470b2beb7cc42a86b6a3e75b704c15 upstream.

In preparation for not using the file at prep time, defer checking if this
file refers to a valid io_uring instance until issue time.

This also means we can get rid of the cleanup flag for splice and tee.

Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-13 20:59:22 +02:00
Jens Axboe
056e1e7c17 io_uring: don't check req->file in io_fsync_prep()
commit ec858afda857e361182ceafc3d2ba2b164b8e889 upstream.

This is a leftover from the really old days where we weren't able to
track and error early if we need a file and it wasn't assigned. Kill
the check.

Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-13 20:59:22 +02:00
Pavel Begunkov
285f5d7240 io_uring: don't touch scm_fp_list after queueing skb
[ Upstream commit a07211e3001435fe8591b992464cd8d5e3c98c5a ]

It's safer to not touch scm_fp_list after we queued an skb to which it
was assigned, there might be races lurking if we screw subtle sync
guarantees on the io_uring side.

Fixes: 6b06314c47e14 ("io_uring: add file set registration")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 20:59:20 +02:00
Pavel Begunkov
50c981bd77 io_uring: nospec index for tags on files update
[ Upstream commit 34bb77184123ae401100a4d156584f12fa630e5c ]

Don't forget to array_index_nospec() for indexes before updating rsrc
tags in __io_sqe_files_update(), just use already safe and precalculated
index @i.

Fixes: c3bdad0271834 ("io_uring: add generic rsrc update with tags")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 20:59:20 +02:00
Pavel Begunkov
0853bd6885 io_uring: fix memory leak of uid in files registration
commit c86d18f4aa93e0e66cda0e55827cd03eea6bc5f8 upstream.

When there are no files for __io_sqe_files_scm() to process in the
range, it'll free everything and return. However, it forgets to put uid.

Fixes: 08a451739a9b5 ("io_uring: allow sparse fixed file sets")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/accee442376f33ce8aaebb099d04967533efde92.1648226048.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-08 14:24:12 +02:00
Jens Axboe
109dda4510 io_uring: terminate manual loop iterator loop correctly for non-vecs
[ Upstream commit 5e929367468c8f97cd1ffb0417316cecfebef94b ]

The fix for not advancing the iterator if we're using fixed buffers is
broken in that it can hit a condition where we don't terminate the loop.
This results in io-wq looping forever, asking to read (or write) 0 bytes
for every subsequent loop.

Reported-by: Joel Jaeschke <joel.jaeschke@gmail.com>
Link: https://github.com/axboe/liburing/issues/549
Fixes: 16c8d2df7ec0 ("io_uring: ensure symmetry in handling iter types in loop_rw_iter()")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:10 +02:00
Jens Axboe
1323976e94 io_uring: don't check unrelated req->open.how in accept request
[ Upstream commit adf3a9e9f556613197583a1884f0de40a8bb6fb9 ]

Looks like a victim of too much copy/paste, we should not be looking
at req->open.how in accept. The point is to check CLOEXEC and error
out, which we don't invalid direct descriptors on exec. Hence any
attempt to get a direct descriptor with CLOEXEC is invalid.

No harm is done here, as req->open.how.flags overlaps with
req->accept.flags, but it's very confusing and might change if either of
those command structs are modified.

Fixes: aaa4db12ef7b ("io_uring: accept directly into fixed file table")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:10 +02:00
Hao Xu
1bd12b7aae io_uring: fix no lock protection for ctx->cq_extra
[ Upstream commit e302f1046f4c209291b07ff7bc4d15ca26891f16 ]

ctx->cq_extra should be protected by completion lock so that the
req_need_defer() does the right check.

Cc: stable@vger.kernel.org
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20211125092103.224502-2-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-08 19:12:33 +01:00
Eric Dumazet
c718ea4e73 io_uring: add a schedule point in io_add_buffers()
commit f240762f88b4b1b58561939ffd44837759756477 upstream.

Looping ~65535 times doing kmalloc() calls can trigger soft lockups,
especially with DEBUG features (like KASAN).

[  253.536212] watchdog: BUG: soft lockup - CPU#64 stuck for 26s! [b219417889:12575]
[  253.544433] Modules linked in: vfat fat i2c_mux_pca954x i2c_mux spidev cdc_acm xhci_pci xhci_hcd sha3_generic gq(O)
[  253.544451] CPU: 64 PID: 12575 Comm: b219417889 Tainted: G S         O      5.17.0-smp-DEV #801
[  253.544457] RIP: 0010:kernel_text_address (./include/asm-generic/sections.h:192 ./include/linux/kallsyms.h:29 kernel/extable.c:67 kernel/extable.c:98)
[  253.544464] Code: 0f 93 c0 48 c7 c1 e0 63 d7 a4 48 39 cb 0f 92 c1 20 c1 0f b6 c1 5b 5d c3 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 53 48 89 fb <48> c7 c0 00 00 80 a0 41 be 01 00 00 00 48 39 c7 72 0c 48 c7 c0 40
[  253.544468] RSP: 0018:ffff8882d8baf4c0 EFLAGS: 00000246
[  253.544471] RAX: 1ffff1105b175e00 RBX: ffffffffa13ef09a RCX: 00000000a13ef001
[  253.544474] RDX: ffffffffa13ef09a RSI: ffff8882d8baf558 RDI: ffffffffa13ef09a
[  253.544476] RBP: ffff8882d8baf4d8 R08: ffff8882d8baf5e0 R09: 0000000000000004
[  253.544479] R10: ffff8882d8baf5e8 R11: ffffffffa0d59a50 R12: ffff8882eab20380
[  253.544481] R13: ffffffffa0d59a50 R14: dffffc0000000000 R15: 1ffff1105b175eb0
[  253.544483] FS:  00000000016d3380(0000) GS:ffff88af48c00000(0000) knlGS:0000000000000000
[  253.544486] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  253.544488] CR2: 00000000004af0f0 CR3: 00000002eabfa004 CR4: 00000000003706e0
[  253.544491] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  253.544492] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  253.544494] Call Trace:
[  253.544496]  <TASK>
[  253.544498] ? io_queue_sqe (fs/io_uring.c:7143)
[  253.544505] __kernel_text_address (kernel/extable.c:78)
[  253.544508] unwind_get_return_address (arch/x86/kernel/unwind_frame.c:19)
[  253.544514] arch_stack_walk (arch/x86/kernel/stacktrace.c:27)
[  253.544517] ? io_queue_sqe (fs/io_uring.c:7143)
[  253.544521] stack_trace_save (kernel/stacktrace.c:123)
[  253.544527] ____kasan_kmalloc (mm/kasan/common.c:39 mm/kasan/common.c:45 mm/kasan/common.c:436 mm/kasan/common.c:515)
[  253.544531] ? ____kasan_kmalloc (mm/kasan/common.c:39 mm/kasan/common.c:45 mm/kasan/common.c:436 mm/kasan/common.c:515)
[  253.544533] ? __kasan_kmalloc (mm/kasan/common.c:524)
[  253.544535] ? kmem_cache_alloc_trace (./include/linux/kasan.h:270 mm/slab.c:3567)
[  253.544541] ? io_issue_sqe (fs/io_uring.c:4556 fs/io_uring.c:4589 fs/io_uring.c:6828)
[  253.544544] ? __io_queue_sqe (fs/io_uring.c:?)
[  253.544551] __kasan_kmalloc (mm/kasan/common.c:524)
[  253.544553] kmem_cache_alloc_trace (./include/linux/kasan.h:270 mm/slab.c:3567)
[  253.544556] ? io_issue_sqe (fs/io_uring.c:4556 fs/io_uring.c:4589 fs/io_uring.c:6828)
[  253.544560] io_issue_sqe (fs/io_uring.c:4556 fs/io_uring.c:4589 fs/io_uring.c:6828)
[  253.544564] ? __kasan_slab_alloc (mm/kasan/common.c:45 mm/kasan/common.c:436 mm/kasan/common.c:469)
[  253.544567] ? __kasan_slab_alloc (mm/kasan/common.c:39 mm/kasan/common.c:45 mm/kasan/common.c:436 mm/kasan/common.c:469)
[  253.544569] ? kmem_cache_alloc_bulk (mm/slab.h:732 mm/slab.c:3546)
[  253.544573] ? __io_alloc_req_refill (fs/io_uring.c:2078)
[  253.544578] ? io_submit_sqes (fs/io_uring.c:7441)
[  253.544581] ? __se_sys_io_uring_enter (fs/io_uring.c:10154 fs/io_uring.c:10096)
[  253.544584] ? __x64_sys_io_uring_enter (fs/io_uring.c:10096)
[  253.544587] ? do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
[  253.544590] ? entry_SYSCALL_64_after_hwframe (??:?)
[  253.544596] __io_queue_sqe (fs/io_uring.c:?)
[  253.544600] io_queue_sqe (fs/io_uring.c:7143)
[  253.544603] io_submit_sqe (fs/io_uring.c:?)
[  253.544608] io_submit_sqes (fs/io_uring.c:?)
[  253.544612] __se_sys_io_uring_enter (fs/io_uring.c:10154 fs/io_uring.c:10096)
[  253.544616] __x64_sys_io_uring_enter (fs/io_uring.c:10096)
[  253.544619] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
[  253.544623] entry_SYSCALL_64_after_hwframe (??:?)

Fixes: ddf0322db79c ("io_uring: add IORING_OP_PROVIDE_BUFFERS")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: io-uring <io-uring@vger.kernel.org>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220215041003.2394784-1-eric.dumazet@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-02 11:47:56 +01:00
Dylan Yudaken
0d773aaf5a io_uring: disallow modification of rsrc_data during quiesce
commit 80912cef18f16f8fe59d1fb9548d4364342be360 upstream.

io_rsrc_ref_quiesce will unlock the uring while it waits for references to
the io_rsrc_data to be killed.
There are other places to the data that might add references to data via
calls to io_rsrc_node_switch.
There is a race condition where this reference can be added after the
completion has been signalled. At this point the io_rsrc_ref_quiesce call
will wake up and relock the uring, assuming the data is unused and can be
freed - although it is actually being used.

To fix this check in io_rsrc_ref_quiesce if a resource has been revived.

Reported-by: syzbot+ca8bf833622a1662745b@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220222161751.995746-1-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-02 11:47:48 +01:00
Jens Axboe
7c83437fb3 io_uring: don't convert to jiffies for waiting on timeouts
commit 228339662b398a59b3560cd571deb8b25b253c7e upstream.

If an application calls io_uring_enter(2) with a timespec passed in,
convert that timespec to ktime_t rather than jiffies. The latter does
not provide the granularity the application may expect, and may in
fact provided different granularity on different systems, depending
on what the HZ value is configured at.

Turn the timespec into an absolute ktime_t, and use that with
schedule_hrtimeout() instead.

Link: https://github.com/axboe/liburing/issues/531
Cc: stable@vger.kernel.org
Reported-by: Bob Chen <chenbo.chen@alibaba-inc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-02 11:47:48 +01:00
Shakeel Butt
246dfbc125 mm: io_uring: allow oom-killer from io_uring_setup
[ Upstream commit 0a3f1e0beacf6cc8ae5f846b0641c1df476e83d6 ]

On an overcommitted system which is running multiple workloads of
varying priorities, it is preferred to trigger an oom-killer to kill a
low priority workload than to let the high priority workload receiving
ENOMEMs. On our memory overcommitted systems, we are seeing a lot of
ENOMEMs instead of oom-kills because io_uring_setup callchain is using
__GFP_NORETRY gfp flag which avoids the oom-killer. Let's remove it and
allow the oom-killer to kill a lower priority job.

Signed-off-by: Shakeel Butt <shakeelb@google.com>
Link: https://lore.kernel.org/r/20220125051736.2981459-1-shakeelb@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-23 12:03:18 +01:00