Merge tag 'v6.6.84' into for/openbmc/dev-6.6

This is the 6.6.84 stable release

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Merge tag 'v6.6.84' into for/openbmc/dev-6.6

This is the 6.6.84 stable release

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# gpg: Signature made Sun 23 Mar 2025 06:23:17 ACDT
# gpg: using RSA key 647F28654894E3BD457199BE38DBBDC86092693E
# gpg: Good signature from "Greg Kroah-Hartman <gregkh@kernel.org>" [marginal]
# gpg: gregkh@kernel.org: Verified 13 signatures in the past 8 weeks. Encrypted
# 0 messages.
# gpg: Warning: you have yet to encrypt a message to this key!
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg: It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 647F 2865 4894 E3BD 4571 99BE 38DB BDC8 6092 693E

show more ...

io_uring/kbuf: use vm_insert_pages() for mmap'ed pbuf ring

Commit 87585b05757dc70545efb434669708d276125559 upstream.

Rather than use remap_pfn_range() for this and manually free later,
switch to us

io_uring/kbuf: use vm_insert_pages() for mmap'ed pbuf ring

Commit 87585b05757dc70545efb434669708d276125559 upstream.

Rather than use remap_pfn_range() for this and manually free later,
switch to using vm_insert_page() and have it Just Work.

This requires a bit of effort on the mmap lookup side, as the ctx
uring_lock isn't held, which otherwise protects buffer_lists from being
torn down, and it's not safe to grab from mmap context that would
introduce an ABBA deadlock between the mmap lock and the ctx uring_lock.
Instead, lookup the buffer_list under RCU, as the the list is RCU freed
already. Use the existing reference count to determine whether it's
possible to safely grab a reference to it (eg if it's not zero already),
and drop that reference when done with the mapping. If the mmap
reference is the last one, the buffer_list and the associated memory can
go away, since the vma insertion has references to the inserted pages at
that point.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

io_uring: unify io_pin_pages()

Commit 1943f96b3816e0f0d3d6686374d6e1d617c8b42c upstream.

Move it into io_uring.c where it belongs, and use it in there as well
rather than have two implementations o

io_uring: unify io_pin_pages()

Commit 1943f96b3816e0f0d3d6686374d6e1d617c8b42c upstream.

Move it into io_uring.c where it belongs, and use it in there as well
rather than have two implementations of this.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

io_uring: use vmap() for ring mapping

Commit 09fc75e0c035a2cabb8caa15cec6e85159dd94f0 upstream.

This is the last holdout which does odd page checking, convert it to
vmap just like what is done for

io_uring: use vmap() for ring mapping

Commit 09fc75e0c035a2cabb8caa15cec6e85159dd94f0 upstream.

This is the last holdout which does odd page checking, convert it to
vmap just like what is done for the non-mmap path.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

io_uring: fix corner case forgetting to vunmap

Commit 43eef70e7e2ac74e7767731dd806720c7fb5e010 upstream.

io_pages_unmap() is a bit tricky in trying to figure whether the pages
were previously vmap'

io_uring: fix corner case forgetting to vunmap

Commit 43eef70e7e2ac74e7767731dd806720c7fb5e010 upstream.

io_pages_unmap() is a bit tricky in trying to figure whether the pages
were previously vmap'ed or not. In particular If there is juts one page
it belives there is no need to vunmap. Paired io_pages_map(), however,
could've failed io_mem_alloc_compound() and attempted to
io_mem_alloc_single(), which does vmap, and that leads to unpaired vmap.

The solution is to fail if io_mem_alloc_compound() can't allocate a
single page. That's the easiest way to deal with it, and those two
functions are getting removed soon, so no need to overcomplicate it.

Cc: stable@vger.kernel.org
Fixes: 3ab1db3c6039e ("io_uring: get rid of remap_pfn_range() for mapping rings/sqes")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/477e75a3907a2fe83249e49c0a92cd480b2c60e0.1732569842.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

io_uring: don't attempt to mmap larger than what the user asks for

Commit 06fe9b1df1086b42718d632aa57e8f7cd1a66a21 upstream.

If IORING_FEAT_SINGLE_MMAP is ignored, as can happen if an application
u

io_uring: don't attempt to mmap larger than what the user asks for

Commit 06fe9b1df1086b42718d632aa57e8f7cd1a66a21 upstream.

If IORING_FEAT_SINGLE_MMAP is ignored, as can happen if an application
uses an ancient liburing or does setup manually, then 3 mmap's are
required to map the ring into userspace. The kernel will still have
collapsed the mappings, however userspace may ask for mapping them
individually. If so, then we should not use the full number of ring
pages, as it may exceed the partial mapping. Doing so will yield an
-EFAULT from vm_insert_pages(), as we pass in more pages than what the
application asked for.

Cap the number of pages to match what the application asked for, for
the particular mapping operation.

Reported-by: Lucas Mülling <lmulling@proton.me>
Link: https://github.com/axboe/liburing/issues/1157
Fixes: 3ab1db3c6039 ("io_uring: get rid of remap_pfn_range() for mapping rings/sqes")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

io_uring: get rid of remap_pfn_range() for mapping rings/sqes

Commit 3ab1db3c6039e02a9deb9d5091d28d559917a645 upstream.

Rather than use remap_pfn_range() for this and manually free later,
switch to

io_uring: get rid of remap_pfn_range() for mapping rings/sqes

Commit 3ab1db3c6039e02a9deb9d5091d28d559917a645 upstream.

Rather than use remap_pfn_range() for this and manually free later,
switch to using vm_insert_pages() and have it Just Work.

If possible, allocate a single compound page that covers the range that
is needed. If that works, then we can just use page_address() on that
page. If we fail to get a compound page, allocate single pages and use
vmap() to map them into the kernel virtual address space.

This just covers the rings/sqes, the other remaining user of the mmap
remap_pfn_range() user will be converted separately. Once that is done,
we can kill the old alloc/free code.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

Merge tag 'v6.6.80' into for/openbmc/dev-6.6

This is the 6.6.80 stable release

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Merge tag 'v6.6.80' into for/openbmc/dev-6.6

This is the 6.6.80 stable release

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# gpg: Signature made Thu 27 Feb 2025 22:47:45 ACDT
# gpg: using RSA key 647F28654894E3BD457199BE38DBBDC86092693E
# gpg: Good signature from "Greg Kroah-Hartman <gregkh@kernel.org>" [marginal]
# gpg: gregkh@kernel.org: Verified 9 signatures in the past 5 weeks. Encrypted
# 0 messages.
# gpg: Warning: you have yet to encrypt a message to this key!
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg: It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 647F 2865 4894 E3BD 4571 99BE 38DB BDC8 6092 693E

show more ...

io_uring: prevent opcode speculation

commit 1e988c3fe1264708f4f92109203ac5b1d65de50b upstream.

sqe->opcode is used for different tables, make sure we santitise it
against speculations.

Cc: stable@

io_uring: prevent opcode speculation

commit 1e988c3fe1264708f4f92109203ac5b1d65de50b upstream.

sqe->opcode is used for different tables, make sure we santitise it
against speculations.

Cc: stable@vger.kernel.org
Fixes: d3656344fea03 ("io_uring: add lookup table for various opcode needs")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Li Zetao <lizetao1@huawei.com>
Link: https://lore.kernel.org/r/7eddbf31c8ca0a3947f8ed98271acc2b4349c016.1739568408.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

Merge tag 'v6.6.78' into for/openbmc/dev-6.6

This is the 6.6.78 stable release

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Merge tag 'v6.6.78' into for/openbmc/dev-6.6

This is the 6.6.78 stable release

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# -----END PGP SIGNATURE-----
# gpg: Signature made Mon 17 Feb 2025 19:10:53 ACDT
# gpg: using RSA key 647F28654894E3BD457199BE38DBBDC86092693E
# gpg: Good signature from "Greg Kroah-Hartman <gregkh@kernel.org>" [marginal]
# gpg: gregkh@kernel.org: Verified 7 signatures in the past 3 weeks. Encrypted
# 0 messages.
# gpg: Warning: you have yet to encrypt a message to this key!
# gpg: Warning: if you think you've seen more signatures by this key and user
# id, then this key might be a forgery! Carefully examine the email address
# for small variations. If the key is suspect, then use
# gpg --tofu-policy bad 647F28654894E3BD457199BE38DBBDC86092693E
# to mark it as being bad.
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg: It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 647F 2865 4894 E3BD 4571 99BE 38DB BDC8 6092 693E

show more ...

io_uring: fix io_req_prep_async with provided buffers

io_req_prep_async() can import provided buffers, commit the ring state
by giving up on that before, it'll be reimported later if needed.

Report

io_uring: fix io_req_prep_async with provided buffers

io_req_prep_async() can import provided buffers, commit the ring state
by giving up on that before, it'll be reimported later if needed.

Reported-by: Muhammad Ramdhan <ramdhan@starlabs.sg>
Reported-by: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Reported-by: Jacob Soo <jacob.soo@starlabs.sg>
Fixes: c7fb19428d67d ("io_uring: add support for ring mapped supplied buffers")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

Merge tag 'v6.6.72' into for/openbmc/dev-6.6

This is the 6.6.72 stable release

io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period

Commit c9a40292a44e78f71258b8522655bffaf5753bdb upstream.

io_eventfd_do_signal() is invoked from an RCU callback, but when
dro

io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period

Commit c9a40292a44e78f71258b8522655bffaf5753bdb upstream.

io_eventfd_do_signal() is invoked from an RCU callback, but when
dropping the reference to the io_ev_fd, it calls io_eventfd_free()
directly if the refcount drops to zero. This isn't correct, as any
potential freeing of the io_ev_fd should be deferred another RCU grace
period.

Just call io_eventfd_put() rather than open-code the dec-and-test and
free, which will correctly defer it another RCU grace period.

Fixes: 21a091b970cd ("io_uring: signal registered eventfd to process deferred task work")
Reported-by: Jann Horn <jannh@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

Merge tag 'v6.6.68' into for/openbmc/dev-6.6

This is the 6.6.68 stable release

io_uring/rw: avoid punting to io-wq directly

Commit 6e6b8c62120a22acd8cb759304e4cd2e3215d488 upstream.

kiocb_done() should care to specifically redirecting requests to io-wq.
Remove the hopping to

io_uring/rw: avoid punting to io-wq directly

Commit 6e6b8c62120a22acd8cb759304e4cd2e3215d488 upstream.

kiocb_done() should care to specifically redirecting requests to io-wq.
Remove the hopping to tw to then queue an io-wq, return -EAGAIN and let
the core code io_uring handle offloading.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/413564e550fe23744a970e1783dfa566291b0e6f.1710799188.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
(cherry picked from commit 6e6b8c62120a22acd8cb759304e4cd2e3215d488)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

io_uring: check if iowq is killed before queuing

commit dbd2ca9367eb19bc5e269b8c58b0b1514ada9156 upstream.

task work can be executed after the task has gone through io_uring
termination, whether it

io_uring: check if iowq is killed before queuing

commit dbd2ca9367eb19bc5e269b8c58b0b1514ada9156 upstream.

task work can be executed after the task has gone through io_uring
termination, whether it's the final task_work run or the fallback path.
In this case, task work will find ->io_wq being already killed and
null'ed, which is a problem if it then tries to forward the request to
io_queue_iowq(). Make io_queue_iowq() fail requests in this case.

Note that it also checks PF_KTHREAD, because the user can first close
a DEFER_TASKRUN ring and shortly after kill the task, in which case
->iowq check would race.

Cc: stable@vger.kernel.org
Fixes: 50c52250e2d74 ("block: implement async io_uring discard cmd")
Fixes: 773af69121ecc ("io_uring: always reissue from task_work context")
Reported-by: Will <willsroot@protonmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/63312b4a2c2bb67ad67b857d17a300e1d3b078e8.1734637909.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

io_uring: Fix registered ring file refcount leak

commit 12d908116f7efd34f255a482b9afc729d7a5fb78 upstream.

Currently, io_uring_unreg_ringfd() (which cleans up registered rings) is
only called on ex

io_uring: Fix registered ring file refcount leak

commit 12d908116f7efd34f255a482b9afc729d7a5fb78 upstream.

Currently, io_uring_unreg_ringfd() (which cleans up registered rings) is
only called on exit, but __io_uring_free (which frees the tctx in which the
registered ring pointers are stored) is also called on execve (via
begin_new_exec -> io_uring_task_cancel -> __io_uring_cancel ->
io_uring_cancel_generic -> __io_uring_free).

This means: A process going through execve while having registered rings
will leak references to the rings' `struct file`.

Fix it by zapping registered rings on execve(). This is implemented by
moving the io_uring_unreg_ringfd() from io_uring_files_cancel() into its
callee __io_uring_cancel(), which is called from io_uring_task_cancel() on
execve.

This could probably be exploited *on 32-bit kernels* by leaking 2^32
references to the same ring, because the file refcount is stored in a
pointer-sized field and get_file() doesn't have protection against
refcount overflow, just a WARN_ONCE(); but on 64-bit it should have no
impact beyond a memory leak.

Cc: stable@vger.kernel.org
Fixes: e7a6c00dc77a ("io_uring: add support for registering ring file descriptors")
Signed-off-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/r/20241218-uring-reg-ring-cleanup-v1-1-8f63e999045b@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

Merge tag 'v6.6.62' into for/openbmc/dev-6.6

This is the 6.6.62 stable release

io_uring: fix possible deadlock in io_register_iowq_max_workers()

commit 73254a297c2dd094abec7c9efee32455ae875bdf upstream.

The io_register_iowq_max_workers() function calls io_put_sq_data(),
which

io_uring: fix possible deadlock in io_register_iowq_max_workers()

commit 73254a297c2dd094abec7c9efee32455ae875bdf upstream.

The io_register_iowq_max_workers() function calls io_put_sq_data(),
which acquires the sqd->lock without releasing the uring_lock.
Similar to the commit 009ad9f0c6ee ("io_uring: drop ctx->uring_lock
before acquiring sqd->lock"), this can lead to a potential deadlock
situation.

To resolve this issue, the uring_lock is released before calling
io_put_sq_data(), and then it is re-acquired after the function call.

This change ensures that the locks are acquired in the correct
order, preventing the possibility of a deadlock.

Suggested-by: Maximilian Heyne <mheyne@amazon.de>
Signed-off-by: Hagar Hemdan <hagarhem@amazon.com>
Link: https://lore.kernel.org/r/20240604130527.3597-1-hagarhem@amazon.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

Merge tag 'v6.6.60' into for/openbmc/dev-6.6

This is the 6.6.60 stable release

io_uring: always lock __io_cqring_overflow_flush

commit 8d09a88ef9d3cb7d21d45c39b7b7c31298d23998 upstream.

Conditional locking is never great, in case of
__io_cqring_overflow_flush(), which is a sl

io_uring: always lock __io_cqring_overflow_flush

commit 8d09a88ef9d3cb7d21d45c39b7b7c31298d23998 upstream.

Conditional locking is never great, in case of
__io_cqring_overflow_flush(), which is a slow path, it's not justified.
Don't handle IOPOLL separately, always grab uring_lock for overflow
flushing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/162947df299aa12693ac4b305dacedab32ec7976.1712708261.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Merge tag 'v6.6.57' into for/openbmc/dev-6.6

This is the 6.6.57 stable release

io_uring: check if we need to reschedule during overflow flush

[ Upstream commit eac2ca2d682f94f46b1973bdf5e77d85d77b8e53 ]

In terms of normal application usage, this list will always be empty.
And

io_uring: check if we need to reschedule during overflow flush

[ Upstream commit eac2ca2d682f94f46b1973bdf5e77d85d77b8e53 ]

In terms of normal application usage, this list will always be empty.
And if an application does overflow a bit, it'll have a few entries.
However, nothing obviously prevents syzbot from running a test case
that generates a ton of overflow entries, and then flushing them can
take quite a while.

Check for needing to reschedule while flushing, and drop our locks and
do so if necessary. There's no state to maintain here as overflows
always prune from head-of-list, hence it's fine to drop and reacquire
the locks at the end of the loop.

Link: https://lore.kernel.org/io-uring/66ed061d.050a0220.29194.0053.GAE@google.com/
Reported-by: syzbot+5fca234bd7eb378ff78e@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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Merge tag 'v6.6.54' into for/openbmc/dev-6.6

This is the 6.6.54 stable release

io_uring: check for presence of task_work rather than TIF_NOTIFY_SIGNAL

commit 04beb6e0e08c30c6f845f50afb7d7953603d7a6f upstream.

If some part of the kernel adds task_work that needs executing, in

io_uring: check for presence of task_work rather than TIF_NOTIFY_SIGNAL

commit 04beb6e0e08c30c6f845f50afb7d7953603d7a6f upstream.

If some part of the kernel adds task_work that needs executing, in terms
of signaling it'll generally use TWA_SIGNAL or TWA_RESUME. Those two
directly translate to TIF_NOTIFY_SIGNAL or TIF_NOTIFY_RESUME, and can
be used for a variety of use case outside of task_work.

However, io_cqring_wait_schedule() only tests explicitly for
TIF_NOTIFY_SIGNAL. This means it can miss if task_work got added for
the task, but used a different kind of signaling mechanism (or none at
all). Normally this doesn't matter as any task_work will be run once
the task exits to userspace, except if:

1) The ring is setup with DEFER_TASKRUN
2) The local work item may generate normal task_work

For condition 2, this can happen when closing a file and it's the final
put of that file, for example. This can cause stalls where a task is
waiting to make progress inside io_cqring_wait(), but there's nothing else
that will wake it up. Hence change the "should we schedule or loop around"
check to check for the presence of task_work explicitly, rather than just
TIF_NOTIFY_SIGNAL as the mechanism. While in there, also change the
ordering of what type of task_work first in terms of ordering, to both
make it consistent with other task_work runs in io_uring, but also to
better handle the case of defer task_work generating normal task_work,
like in the above example.

Reported-by: Jan Hendrik Farr <kernel@jfarr.cc>
Link: https://github.com/axboe/liburing/issues/1235
Cc: stable@vger.kernel.org
Fixes: 846072f16eed ("io_uring: mimimise io_cqring_wait_schedule")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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