Merge tag 'nfsd-6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

- Fix a couple of use-after-free bugs

* tag 'nfsd-6.12-2' of git://git.kernel.

Merge tag 'nfsd-6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

- Fix a couple of use-after-free bugs

* tag 'nfsd-6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
nfsd: cancel nfsd_shrinker_work using sync mode in nfs4_state_shutdown_net
nfsd: fix race between laundromat and free_stateid

show more ...

nfsd: cancel nfsd_shrinker_work using sync mode in nfs4_state_shutdown_net

In the normal case, when we excute `echo 0 > /proc/fs/nfsd/threads`, the
function `nfs4_state_destroy_net` in `nfs4_state_s

nfsd: cancel nfsd_shrinker_work using sync mode in nfs4_state_shutdown_net

In the normal case, when we excute `echo 0 > /proc/fs/nfsd/threads`, the
function `nfs4_state_destroy_net` in `nfs4_state_shutdown_net` will
release all resources related to the hashed `nfs4_client`. If the
`nfsd_client_shrinker` is running concurrently, the `expire_client`
function will first unhash this client and then destroy it. This can
lead to the following warning. Additionally, numerous use-after-free
errors may occur as well.

nfsd_client_shrinker echo 0 > /proc/fs/nfsd/threads

expire_client nfsd_shutdown_net
unhash_client ...
nfs4_state_shutdown_net
/* won't wait shrinker exit */
/* cancel_work(&nn->nfsd_shrinker_work)
* nfsd_file for this /* won't destroy unhashed client1 */
* client1 still alive nfs4_state_destroy_net
*/

nfsd_file_cache_shutdown
/* trigger warning */
kmem_cache_destroy(nfsd_file_slab)
kmem_cache_destroy(nfsd_file_mark_slab)
/* release nfsd_file and mark */
__destroy_client

====================================================================
BUG nfsd_file (Not tainted): Objects remaining in nfsd_file on
__kmem_cache_shutdown()
--------------------------------------------------------------------
CPU: 4 UID: 0 PID: 764 Comm: sh Not tainted 6.12.0-rc3+ #1

dump_stack_lvl+0x53/0x70
slab_err+0xb0/0xf0
__kmem_cache_shutdown+0x15c/0x310
kmem_cache_destroy+0x66/0x160
nfsd_file_cache_shutdown+0xac/0x210 [nfsd]
nfsd_destroy_serv+0x251/0x2a0 [nfsd]
nfsd_svc+0x125/0x1e0 [nfsd]
write_threads+0x16a/0x2a0 [nfsd]
nfsctl_transaction_write+0x74/0xa0 [nfsd]
vfs_write+0x1a5/0x6d0
ksys_write+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e

====================================================================
BUG nfsd_file_mark (Tainted: G B W ): Objects remaining
nfsd_file_mark on __kmem_cache_shutdown()
--------------------------------------------------------------------

dump_stack_lvl+0x53/0x70
slab_err+0xb0/0xf0
__kmem_cache_shutdown+0x15c/0x310
kmem_cache_destroy+0x66/0x160
nfsd_file_cache_shutdown+0xc8/0x210 [nfsd]
nfsd_destroy_serv+0x251/0x2a0 [nfsd]
nfsd_svc+0x125/0x1e0 [nfsd]
write_threads+0x16a/0x2a0 [nfsd]
nfsctl_transaction_write+0x74/0xa0 [nfsd]
vfs_write+0x1a5/0x6d0
ksys_write+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e

To resolve this issue, cancel `nfsd_shrinker_work` using synchronous
mode in nfs4_state_shutdown_net.

Fixes: 7c24fa225081 ("NFSD: replace delayed_work with work_struct for nfsd_client_shrinker")
Signed-off-by: Yang Erkun <yangerkun@huaweicloud.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

show more ...

nfsd: fix race between laundromat and free_stateid

There is a race between laundromat handling of revoked delegations
and a client sending free_stateid operation. Laundromat thread
finds that delega

nfsd: fix race between laundromat and free_stateid

There is a race between laundromat handling of revoked delegations
and a client sending free_stateid operation. Laundromat thread
finds that delegation has expired and needs to be revoked so it
marks the delegation stid revoked and it puts it on a reaper list
but then it unlock the state lock and the actual delegation revocation
happens without the lock. Once the stid is marked revoked a racing
free_stateid processing thread does the following (1) it calls
list_del_init() which removes it from the reaper list and (2) frees
the delegation stid structure. The laundromat thread ends up not
calling the revoke_delegation() function for this particular delegation
but that means it will no release the lock lease that exists on
the file.

Now, a new open for this file comes in and ends up finding that
lease list isn't empty and calls nfsd_breaker_owns_lease() which ends
up trying to derefence a freed delegation stateid. Leading to the
followint use-after-free KASAN warning:

kernel: ==================================================================
kernel: BUG: KASAN: slab-use-after-free in nfsd_breaker_owns_lease+0x140/0x160 [nfsd]
kernel: Read of size 8 at addr ffff0000e73cd0c8 by task nfsd/6205
kernel:
kernel: CPU: 2 UID: 0 PID: 6205 Comm: nfsd Kdump: loaded Not tainted 6.11.0-rc7+ #9
kernel: Hardware name: Apple Inc. Apple Virtualization Generic Platform, BIOS 2069.0.0.0.0 08/03/2024
kernel: Call trace:
kernel: dump_backtrace+0x98/0x120
kernel: show_stack+0x1c/0x30
kernel: dump_stack_lvl+0x80/0xe8
kernel: print_address_description.constprop.0+0x84/0x390
kernel: print_report+0xa4/0x268
kernel: kasan_report+0xb4/0xf8
kernel: __asan_report_load8_noabort+0x1c/0x28
kernel: nfsd_breaker_owns_lease+0x140/0x160 [nfsd]
kernel: nfsd_file_do_acquire+0xb3c/0x11d0 [nfsd]
kernel: nfsd_file_acquire_opened+0x84/0x110 [nfsd]
kernel: nfs4_get_vfs_file+0x634/0x958 [nfsd]
kernel: nfsd4_process_open2+0xa40/0x1a40 [nfsd]
kernel: nfsd4_open+0xa08/0xe80 [nfsd]
kernel: nfsd4_proc_compound+0xb8c/0x2130 [nfsd]
kernel: nfsd_dispatch+0x22c/0x718 [nfsd]
kernel: svc_process_common+0x8e8/0x1960 [sunrpc]
kernel: svc_process+0x3d4/0x7e0 [sunrpc]
kernel: svc_handle_xprt+0x828/0xe10 [sunrpc]
kernel: svc_recv+0x2cc/0x6a8 [sunrpc]
kernel: nfsd+0x270/0x400 [nfsd]
kernel: kthread+0x288/0x310
kernel: ret_from_fork+0x10/0x20

This patch proposes a fixed that's based on adding 2 new additional
stid's sc_status values that help coordinate between the laundromat
and other operations (nfsd4_free_stateid() and nfsd4_delegreturn()).

First to make sure, that once the stid is marked revoked, it is not
removed by the nfsd4_free_stateid(), the laundromat take a reference
on the stateid. Then, coordinating whether the stid has been put
on the cl_revoked list or we are processing FREE_STATEID and need to
make sure to remove it from the list, each check that state and act
accordingly. If laundromat has added to the cl_revoke list before
the arrival of FREE_STATEID, then nfsd4_free_stateid() knows to remove
it from the list. If nfsd4_free_stateid() finds that operations arrived
before laundromat has placed it on cl_revoke list, it marks the state
freed and then laundromat will no longer add it to the list.

Also, for nfsd4_delegreturn() when looking for the specified stid,
we need to access stid that are marked removed or freeable, it means
the laundromat has started processing it but hasn't finished and this
delegreturn needs to return nfserr_deleg_revoked and not
nfserr_bad_stateid. The latter will not trigger a FREE_STATEID and the
lack of it will leave this stid on the cl_revoked list indefinitely.

Fixes: 2d4a532d385f ("nfsd: ensure that clp->cl_revoked list is protected by clp->cl_lock")
CC: stable@vger.kernel.org
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

show more ...

Merge branch 'linus' into sched/urgent, to resolve conflict

Conflicts:
kernel/sched/ext.c

There's a context conflict between this upstream commit:

3fdb9ebcec10 sched_ext: Start schedulers with

Merge branch 'linus' into sched/urgent, to resolve conflict

Conflicts:
kernel/sched/ext.c

There's a context conflict between this upstream commit:

3fdb9ebcec10 sched_ext: Start schedulers with consistent p->scx.slice values

... and this fix in sched/urgent:

98442f0ccd82 sched: Fix delayed_dequeue vs switched_from_fair()

Resolve it.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

show more ...

Merge tag 'nfsd-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

- Fix NFSD bring-up / shutdown

- Fix a UAF when releasing a stateid

* tag 'n

Merge tag 'nfsd-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

- Fix NFSD bring-up / shutdown

- Fix a UAF when releasing a stateid

* tag 'nfsd-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
nfsd: fix possible badness in FREE_STATEID
nfsd: nfsd_destroy_serv() must call svc_destroy() even if nfsd_startup_net() failed
NFSD: Mark filecache "down" if init fails

show more ...

nfsd: fix possible badness in FREE_STATEID

When multiple FREE_STATEIDs are sent for the same delegation stateid,
it can lead to a possible either use-after-free or counter refcount
underflow errors.

nfsd: fix possible badness in FREE_STATEID

When multiple FREE_STATEIDs are sent for the same delegation stateid,
it can lead to a possible either use-after-free or counter refcount
underflow errors.

In nfsd4_free_stateid() under the client lock we find a delegation
stateid, however the code drops the lock before calling nfs4_put_stid(),
that allows another FREE_STATE to find the stateid again. The first one
will proceed to then free the stateid which leads to either
use-after-free or decrementing already zeroed counter.

Fixes: 3f29cc82a84c ("nfsd: split sc_status out of sc_type")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

show more ...

Merge remote-tracking branch 'torvalds/master' into perf-tools

To pick up changes in other trees that may affect perf, such as libbpf
and in general the header files that perf has copies of, so that

Merge remote-tracking branch 'torvalds/master' into perf-tools

To pick up changes in other trees that may affect perf, such as libbpf
and in general the header files that perf has copies of, so that we can
do the sync with the kernel sources.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

show more ...

Merge tag 'kvmarm-fixes-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.12, take #1

- Fix pKVM error path on init, making sure we do not chang

Merge tag 'kvmarm-fixes-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.12, take #1

- Fix pKVM error path on init, making sure we do not change critical
system registers as we're about to fail

- Make sure that the host's vector length is at capped by a value
common to all CPUs

- Fix kvm_has_feat*() handling of "negative" features, as the current
code is pretty broken

- Promote Joey to the status of official reviewer, while James steps
down -- hopefully only temporarly

show more ...

Merge tag 'asoc-fix-v6.12-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v6.12

A bunch of fixes here that came in during the merge window and t

Merge tag 'asoc-fix-v6.12-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v6.12

A bunch of fixes here that came in during the merge window and the first
week of release, plus some new quirks and device IDs. There's nothing
major here, it's a bit bigger than it might've been due to there being
no fixes sent during the merge window due to your vacation.

show more ...

Merge remote-tracking branch 'drm/drm-fixes' into drm-misc-fixes

Required for a panthor fix that broke when
FOP_UNSIGNED_OFFSET was added in place of FMODE_UNSIGNED_OFFSET.

Signed-off-by: Maarten L

Merge remote-tracking branch 'drm/drm-fixes' into drm-misc-fixes

Required for a panthor fix that broke when
FOP_UNSIGNED_OFFSET was added in place of FMODE_UNSIGNED_OFFSET.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

show more ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Cross-merge networking fixes after downstream PR.

No conflicts and no adjacent changes.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Merge 6.11-rc7 into char-misc-next

We need the char-misc fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge 6.11-rc6 into usb-next

We need the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge tag 'v6.11' into for-6.12/block

Merge in 6.11 final to get the fix for preventing deadlocks on an
elevator switch, as there's a fixup for that patch.

* tag 'v6.11': (1788 commits)
Linux 6.1

Merge tag 'v6.11' into for-6.12/block

Merge in 6.11 final to get the fix for preventing deadlocks on an
elevator switch, as there's a fixup for that patch.

* tag 'v6.11': (1788 commits)
Linux 6.11
Revert "KVM: VMX: Always honor guest PAT on CPUs that support self-snoop"
pinctrl: pinctrl-cy8c95x0: Fix regcache
cifs: Fix signature miscalculation
mm: avoid leaving partial pfn mappings around in error case
drm/xe/client: add missing bo locking in show_meminfo()
drm/xe/client: fix deadlock in show_meminfo()
drm/xe/oa: Enable Xe2+ PES disaggregation
drm/xe/display: fix compat IS_DISPLAY_STEP() range end
drm/xe: Fix access_ok check in user_fence_create
drm/xe: Fix possible UAF in guc_exec_queue_process_msg
drm/xe: Remove fence check from send_tlb_invalidation
drm/xe/gt: Remove double include
net: netfilter: move nf flowtable bpf initialization in nf_flow_table_module_init()
PCI: Fix potential deadlock in pcim_intx()
workqueue: Clear worker->pool in the worker thread context
net: tighten bad gso csum offset check in virtio_net_hdr
netlink: specs: mptcp: fix port endianness
net: dpaa: Pad packets to ETH_ZLEN
mptcp: pm: Fix uaf in __timer_delete_sync
...

show more ...

Merge tag 'nfsd-6.12' into linux-next-with-localio

NFSD 6.12 Release Notes

Notable features of this release include:

- Pre-requisites for automatically determining the RPC server thread
count
-

Merge tag 'nfsd-6.12' into linux-next-with-localio

NFSD 6.12 Release Notes

Notable features of this release include:

- Pre-requisites for automatically determining the RPC server thread
count
- Clean-up and preparation for supporting LOCALIO, which will be
merged via the NFS client tree
- Enhancements and fixes to NFSv4.2 COPY offload
- A new Python-based tool for generating kernel SunRPC XDR encoding
and decoding functions, added as an aid for prototyping features
in protocols based on the Linux kernel's SunRPC implementation.

As always I am grateful to the NFSD contributors, reviewers,
testers, and bug reporters who participated during this cycle.

show more ...

Merge branch 'next' into for-linus

Prepare input updates for 6.12 merge window.

Merge branch 'ib/6.11-rc6-matrix-keypad-spitz' into next

Bring in changes removing support for platform data from matrix-keypad
driver.

Merge tag 'v6.10' into next

Sync up with mainline to bring in device_for_each_child_node_scoped()
and other newer APIs.

Merge tag 'nfsd-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd updates from Chuck Lever:
"Notable features of this release include:

- Pre-requisites for automaticall

Merge tag 'nfsd-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd updates from Chuck Lever:
"Notable features of this release include:

- Pre-requisites for automatically determining the RPC server thread
count

- Clean-up and preparation for supporting LOCALIO, which will be
merged via the NFS client tree

- Enhancements and fixes to NFSv4.2 COPY offload

- A new Python-based tool for generating kernel SunRPC XDR encoding
and decoding functions, added as an aid for prototyping features in
protocols based on the Linux kernel's SunRPC implementation

As always I am grateful to the NFSD contributors, reviewers, testers,
and bug reporters who participated during this cycle"

* tag 'nfsd-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (57 commits)
xdrgen: Prevent reordering of encoder and decoder functions
xdrgen: typedefs should use the built-in string and opaque functions
xdrgen: Fix return code checking in built-in XDR decoders
tools: Add xdrgen
nfsd: fix delegation_blocked() to block correctly for at least 30 seconds
nfsd: fix initial getattr on write delegation
nfsd: untangle code in nfsd4_deleg_getattr_conflict()
nfsd: enforce upper limit for namelen in __cld_pipe_inprogress_downcall()
nfsd: return -EINVAL when namelen is 0
NFSD: Wrap async copy operations with trace points
NFSD: Clean up extra whitespace in trace_nfsd_copy_done
NFSD: Record the callback stateid in copy tracepoints
NFSD: Display copy stateids with conventional print formatting
NFSD: Limit the number of concurrent async COPY operations
NFSD: Async COPY result needs to return a write verifier
nfsd: avoid races with wake_up_var()
nfsd: use clear_and_wake_up_bit()
sunrpc: xprtrdma: Use ERR_CAST() to return
NFSD: Annotate struct pnfs_block_deviceaddr with __counted_by()
nfsd: call cache_put if xdr_reserve_space returns NULL
...

show more ...

Merge tag 'i2c-host-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux into i2c/for-mergewindow

The DesignWare and the Renesas I2C drivers have received most of
the changes in t

Merge tag 'i2c-host-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux into i2c/for-mergewindow

The DesignWare and the Renesas I2C drivers have received most of
the changes in this pull request.

The first has has undergone through a series of cleanups that
have been sent to the mailing list a year ago for the first time
and finally get merged in this pull request. They are many, from
typos (e.g. i2/i2c), to cosmetics, to refactoring (e.g. move
inline functions to librarieas) and many others.

Besides that, all the DesignWare Kconfig options have been
grouped under the I2C_DESIGNWARE_CORE and this required some
adaptation in many of the kernel configuration files for
different arm and mips boards.

Follows the list of the rest of the changes grouped by type of
change.

Cleanups
--------
The Qualcomm Geni platform improves the exit path in the runtime
resume function.

The Intel LJCA driver loses "target_addr" parameter in
ljca_i2c_stop() because it was unused.

The MediaTek controller intializes the restart_flag in the
transfer function using the ternary conditional operator ("? :")
instead of initializing it in different parts.

Constified a few global data structures in the virtio driver.

The Renesas driver simplifies the bus speed handling in the init
function making it more readable.

Improved an if/else statement in probe function of the Renesas
R-Car driver.

The iMX/MXC driver switches to using the RUNTIME_PM_OPS() instead
of SET_RUNTIME_PM_OPS().

Still in the iMX/MXC driver a comma ',' has been replaced by a
semicolon ';', while in different drivers the ',' has been
removed from the '{ }' delimiters.

Finally three devm_clk_get_enabled() have been used to simplify
the devm_clk_get/clk_prepare_enable tuple in the Renesas EMEV2,
Ingenic and MPC drivers.

Refactors
---------
The Nuvoton fixes a potential out of boundary array access. This
is not a bug fix because the issue could never occur due to
hardware not having the properties listed in the array. The
change makes the driver more future proof and, at the same time,
silences code analyzers.

Improvements
------------
The Renesas I2C (riic) driver undergoes several patches improving
the runtime power management handling.

The Intel i801 driver uses a more descriptive adapter's name to
show the presence of the IDF feature.

In the Intel Denverton (ismt) adapter the pending transactions
are killed when irq's can't complete their handling, triggering a
timeout. This could have been considered as a bug fix, but
because, standing to Vasily, it's very sporadic, I preferred
considering the patch rather as an improvement.

New Feature
-----------
The Renesas I2C (riic) driver now supports the fast mode plus.

New support
-----------
Added support for:

- Renesas R9A08G045
- Rockchip RK3576
- KEBA I2C
- Theobroma Systems Mule Multiplexer.

The Keba comes with a new driver, i2c-keba.c.
The Mule is an i2c multiplexer and it also comes with a new
driver, mux/i2c-mux-mule.c.

Core patch
----------
This pull request includes also a patch in the I2C framework, in
i2c-core-base.c where the runtime PM functions have been replaced
in order to allow to be accessed during the device add.

Devicetree
----------
Some cleanups in the devicetree, as well. nVidia and Qualcomm
bindings improve their "if:then:" blocks. While the aspeed
binding loses the "multi-master" property because it was
redundant.

The i2c-sprd binding has been converted to YAML.

show more ...

nfsd: fix delegation_blocked() to block correctly for at least 30 seconds

The pair of bloom filtered used by delegation_blocked() was intended to
block delegations on given filehandles for between 3

nfsd: fix delegation_blocked() to block correctly for at least 30 seconds

The pair of bloom filtered used by delegation_blocked() was intended to
block delegations on given filehandles for between 30 and 60 seconds. A
new filehandle would be recorded in the "new" bit set. That would then
be switch to the "old" bit set between 0 and 30 seconds later, and it
would remain as the "old" bit set for 30 seconds.

Unfortunately the code intended to clear the old bit set once it reached
30 seconds old, preparing it to be the next new bit set, instead cleared
the *new* bit set before switching it to be the old bit set. This means
that the "old" bit set is always empty and delegations are blocked
between 0 and 30 seconds.

This patch updates bd->new before clearing the set with that index,
instead of afterwards.

Reported-by: Olga Kornievskaia <okorniev@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 6282cd565553 ("NFSD: Don't hand out delegations for 30 seconds after recalling them.")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

show more ...

nfsd: fix initial getattr on write delegation

At this point in compound processing, currentfh refers to the parent of
the file, not the file itself. Get the correct dentry from the delegation
statei

nfsd: fix initial getattr on write delegation

At this point in compound processing, currentfh refers to the parent of
the file, not the file itself. Get the correct dentry from the delegation
stateid instead.

Fixes: c5967721e106 ("NFSD: handle GETATTR conflict with write delegation")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

show more ...

nfsd: untangle code in nfsd4_deleg_getattr_conflict()

The code in nfsd4_deleg_getattr_conflict() is convoluted and buggy.

With this patch we:
- properly handle non-nfsd leases. We must not assume

nfsd: untangle code in nfsd4_deleg_getattr_conflict()

The code in nfsd4_deleg_getattr_conflict() is convoluted and buggy.

With this patch we:
- properly handle non-nfsd leases. We must not assume flc_owner is a
delegation unless fl_lmops == &nfsd_lease_mng_ops
- move the main code out of the for loop
- have a single exit which calls nfs4_put_stid()
(and other exits which don't need to call that)

[ jlayton: refactored on top of Neil's other patch: nfsd: fix
nfsd4_deleg_getattr_conflict in presence of third party lease ]

Fixes: c5967721e106 ("NFSD: handle GETATTR conflict with write delegation")
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

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NFSD: Limit the number of concurrent async COPY operations

Nothing appears to limit the number of concurrent async COPY
operations that clients can start. In addition, AFAICT each async
COPY can cop

NFSD: Limit the number of concurrent async COPY operations

Nothing appears to limit the number of concurrent async COPY
operations that clients can start. In addition, AFAICT each async
COPY can copy an unlimited number of 4MB chunks, so can run for a
long time. Thus IMO async COPY can become a DoS vector.

Add a restriction mechanism that bounds the number of concurrent
background COPY operations. Start simple and try to be fair -- this
patch implements a per-namespace limit.

An async COPY request that occurs while this limit is exceeded gets
NFS4ERR_DELAY. The requesting client can choose to send the request
again after a delay or fall back to a traditional read/write style
copy.

If there is need to make the mechanism more sophisticated, we can
visit that in future patches.

Cc: stable@vger.kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

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nfsd: avoid races with wake_up_var()

wake_up_var() needs a barrier after the important change is made in the
var and before wake_up_var() is called, else it is possible that a wake
up won't be sent

nfsd: avoid races with wake_up_var()

wake_up_var() needs a barrier after the important change is made in the
var and before wake_up_var() is called, else it is possible that a wake
up won't be sent when it should.

In each case here the var is changed in an "atomic" manner, so
smb_mb__after_atomic() is sufficient.

In one case the important change (removing the lease) is performed
*after* the wake_up, which is backwards. The code survives in part
because the wait_var_event is given a timeout.

This patch adds the required barriers and calls destroy_delegation()
*before* waking any threads waiting for the delegation to be destroyed.

Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

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