commit 6889ae1b4df1579bcdffef023e2ea9a982565dff upstream.

[  114.987980][ T5313] WARNING: CPU: 6 PID: 5313 at io_uring/io_uring.c:872 io_req_post_cqe+0x12e/0x4f0
[  114.991597][ T5313] RIP: 0010:io_req_post_cqe+0x12e/0x4f0
[  115.001880][ T5313] Call Trace:
[  115.002222][ T5313]  <TASK>
[  115.007813][ T5313]  io_send+0x4fe/0x10f0
[  115.009317][ T5313]  io_issue_sqe+0x1a6/0x1740
[  115.012094][ T5313]  io_wq_submit_work+0x38b/0xed0
[  115.013223][ T5313]  io_worker_handle_work+0x62a/0x1600
[  115.013876][ T5313]  io_wq_worker+0x34f/0xdf0

As the comment states, io_req_post_cqe() should only be used by
multishot requests, i.e. REQ_F_APOLL_MULTISHOT, which bundled sends are
not. Add a flag signifying whether a request wants to post multiple
CQEs. Eventually REQ_F_APOLL_MULTISHOT should imply the new flag, but
that's left out for simplicity.

Cc: stable@vger.kernel.org
Fixes: a05d1f625c7aa ("io_uring/net: support bundles for send")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8b611dbb54d1cd47a88681f5d38c84d0c02bc563.1743067183.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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>

[ Upstream commit 29b95ac917927ce9f95bf38797e16333ecb489b1 ]

With *ENTER_EXT_ARG_REG instead of passing a user pointer with arguments
for the waiting loop the user can specify an offset into a pre-mapped
region of memory, in which case the
[offset, offset + sizeof(io_uring_reg_wait)) will be intepreted as the
argument.

As we address a kernel array using a user given index, it'd be a subject
to speculation type of exploits. Use array_index_nospec() to prevent
that. Make sure to pass not the full region size but truncate by the
maximum offset allowed considering the structure size.

Fixes: d617b3147d54c ("io_uring: restore back registered wait arguments")
Fixes: aa00f67adc2c0 ("io_uring: add support for fixed wait regions")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1e3d9da7c43d619de7bcf41d1cd277ab2688c443.1733694126.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Pull io_uring fixes from Jens Axboe:

 - Fix for multishot timeout updates only using the updated value for
   the first invocation, not subsequent ones

 - Silence a false positive lockdep warning

 - Fix the eventfd signaling and putting RCU logic

 - Fix fault injected SQPOLL setup not clearing the task pointer in the
   error path

 - Fix local task_work looking at the SQPOLL thread rather than just
   signaling the safe variant. Again one of those theoretical issues,
   which should be closed up none the less.

* tag 'io_uring-6.13-20250111' of git://git.kernel.dk/linux:
  io_uring: don't touch sqd->thread off tw add
  io_uring/sqpoll: zero sqd->thread on tctx errors
  io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period
  io_uring: silence false positive warnings
  io_uring/timeout: fix multishot updates

With IORING_SETUP_SQPOLL all requests are created by the SQPOLL task,
which means that req->task should always match sqd->thread. Since
accesses to sqd->thread should be separately protected, use req->task
in io_req_normal_work_add() instead.

Note, in the eyes of io_req_normal_work_add(), the SQPOLL task struct
is always pinned and alive, and sqd->thread can either be the task or
NULL. It's only problematic if the compiler decides to reload the value
after the null check, which is not so likely.

Cc: stable@vger.kernel.org
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Reported-by: lizetao <lizetao1@huawei.com>
Fixes: 78f9b61bd8e54 ("io_uring: wake SQPOLL task when task_work is added to an empty queue")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1cbbe72cf32c45a8fee96026463024cd8564a7d7.1736541357.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull vfs fixes from Christian Brauner:
 "afs:

   - Fix the maximum cell name length

   - Fix merge preference rule failure condition

  fuse:

   - Fix fuse_get_user_pages() so it doesn't risk misleading the caller
     to think pages have been allocated when they actually haven't

   - Fix direct-io folio offset and length calculation

  netfs:

   - Fix async direct-io handling

   - Fix read-retry for filesystems that don't provide a
     ->prepare_read() method

  vfs:

   - Prevent truncating 64-bit offsets to 32-bits in iomap

   - Fix memory barrier interactions when polling

   - Remove MNT_ONRB to fix concurrent modification of @mnt->mnt_flags
     leading to MNT_ONRB to not be raised and invalid access to a list
     member"

* tag 'vfs-6.13-rc7.fixes.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  poll: kill poll_does_not_wait()
  sock_poll_wait: kill the no longer necessary barrier after poll_wait()
  io_uring_poll: kill the no longer necessary barrier after poll_wait()
  poll_wait: kill the obsolete wait_address check
  poll_wait: add mb() to fix theoretical race between waitqueue_active() and .poll()
  afs: Fix merge preference rule failure condition
  netfs: Fix read-retry for fs with no ->prepare_read()
  netfs: Fix kernel async DIO
  fs: kill MNT_ONRB
  iomap: avoid avoid truncating 64-bit offset to 32 bits
  afs: Fix the maximum cell name length
  fuse: Set *nbytesp=0 in fuse_get_user_pages on allocation failure
  fuse: fix direct io folio offset and length calculation

Bring in the fixes for __pollwait() and waitqueue_active() interactions.

Signed-off-by: Christian Brauner <brauner@kernel.org>

Now that poll_wait() provides a full barrier we can remove smp_rmb() from
io_uring_poll().

In fact I don't think smp_rmb() was correct, it can't serialize LOADs and
STOREs.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20250107162730.GA18940@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

Pull btrfs fixes from David Sterba:
 "A few more fixes.

  Besides the one-liners in Btrfs there's fix to the io_uring and
  encoded read integration (added in this development cycle). The update
  to io_uring provides more space for the ongoing command that is then
  used in Btrfs to handle some cases.

   - io_uring and encoded read:
       - provide stable storage for io_uring command data
       - make a copy of encoded read ioctl call, reuse that in case the
         call would block and will be called again

   - properly initialize zlib context for hardware compression on s390

   - fix max extent size calculation on filesystems with non-zoned
     devices

   - fix crash in scrub on crafted image due to invalid extent tree"

* tag 'for-6.13-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: zlib: fix avail_in bytes for s390 zlib HW compression path
  btrfs: zoned: calculate max_extent_size properly on non-zoned setup
  btrfs: avoid NULL pointer dereference if no valid extent tree
  btrfs: don't read from userspace twice in btrfs_uring_encoded_read()
  io_uring: add io_uring_cmd_get_async_data helper
  io_uring/cmd: add per-op data to struct io_uring_cmd_data
  io_uring/cmd: rename struct uring_cache to io_uring_cmd_data

In preparation for making this more generically available for
->uring_cmd() usage that needs stable command data, rename it and move
it to io_uring/cmd.h instead.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: David Sterba <dsterba@suse.com>