NFS: Avoid flushing data while holding directory locks in nfs_rename()

The Linux client assumes that all filehandles are non-volatile for
renames within the same directory (otherwise sillyrename can

NFS: Avoid flushing data while holding directory locks in nfs_rename()

The Linux client assumes that all filehandles are non-volatile for
renames within the same directory (otherwise sillyrename cannot work).
However, the existence of the Linux 'subtree_check' export option has
meant that nfs_rename() has always assumed it needs to flush writes
before attempting to rename.

Since NFSv4 does allow the client to query whether or not the server
exhibits this behaviour, and since knfsd does actually set the
appropriate flag when 'subtree_check' is enabled on an export, it
should be OK to optimise away the write flushing behaviour in the cases
where it is clearly not needed.

Signed-off-by: Trond Myklebust <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>

show more ...

NFS: Treat ENETUNREACH errors as fatal in containers

Propagate the NFS_MOUNT_NETUNREACH_FATAL flag to work with the generic
NFS client. If the flag is set, the client will receive ENETDOWN and
ENETU

NFS: Treat ENETUNREACH errors as fatal in containers

Propagate the NFS_MOUNT_NETUNREACH_FATAL flag to work with the generic
NFS client. If the flag is set, the client will receive ENETDOWN and
ENETUNREACH errors from the RPC layer, and is expected to treat them as
being fatal.

Signed-off-by: Trond Myklebust <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Tested-by: Jeff Layton <[email protected]>
Acked-by: Chuck Lever <[email protected]>

show more ...

NFS: Add a mount option to make ENETUNREACH errors fatal

If the NFS client was initially created in a container, and that
container is torn down, there is usually no possibity to go back and
destroy

NFS: Add a mount option to make ENETUNREACH errors fatal

If the NFS client was initially created in a container, and that
container is torn down, there is usually no possibity to go back and
destroy any NFS clients that are hung because their virtual network
devices have been unlinked.

Add a flag that tells the NFS client that in these circumstances, it
should treat ENETDOWN and ENETUNREACH errors as fatal to the NFS client.

The option defaults to being on when the mount happens from inside a net
namespace that is not "init_net".

Signed-off-by: Trond Myklebust <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Tested-by: Jeff Layton <[email protected]>
Acked-by: Chuck Lever <[email protected]>

show more ...

NFS: Extend rdirplus mount option with "force|none"

There are certain users that wish to force the NFS client to choose
READDIRPLUS over READDIR for a particular mount. Update the "rdirplus" mount

NFS: Extend rdirplus mount option with "force|none"

There are certain users that wish to force the NFS client to choose
READDIRPLUS over READDIR for a particular mount. Update the "rdirplus" mount
option to optionally accept values. For "rdirplus=force", the NFS client
will always attempt to use READDDIRPLUS. The setting of "rdirplus=none" is
aliased to the existing "nordirplus".

Signed-off-by: Benjamin Coddington <[email protected]>
Link: https://lore.kernel.org/r/c4cf0de4c8be0930b91bc74bee310d289781cd3b.1741885071.git.bcodding@redhat.com
Signed-off-by: Trond Myklebust <[email protected]>

show more ...

NFS: Implement NFSv4.2's OFFLOAD_STATUS operation

Enable the Linux NFS client to observe the progress of an offloaded
asynchronous COPY operation. This new operation will be put to use
in a subseque

NFS: Implement NFSv4.2's OFFLOAD_STATUS operation

Enable the Linux NFS client to observe the progress of an offloaded
asynchronous COPY operation. This new operation will be put to use
in a subsequent patch.

Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Chuck Lever <[email protected]>
Reviewed-by: Benjamin Coddington <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Trond Myklebust <[email protected]>

show more ...

NFSv4: Avoid unnecessary scans of filesystems for delayed delegations

The amount of looping through the list of delegations is occasionally
leading to soft lockups. If the state manager was asked to

NFSv4: Avoid unnecessary scans of filesystems for delayed delegations

The amount of looping through the list of delegations is occasionally
leading to soft lockups. If the state manager was asked to manage the
delayed return of delegations, then only scan those filesystems
containing delegations that were marked as being delayed.

Fixes: be20037725d1 ("NFSv4: Fix delegation return in cases where we have to retry")
Signed-off-by: Trond Myklebust <[email protected]>

show more ...

NFSv4: Avoid unnecessary scans of filesystems for expired delegations

The amount of looping through the list of delegations is occasionally
leading to soft lockups. If the state manager was asked t

NFSv4: Avoid unnecessary scans of filesystems for expired delegations

The amount of looping through the list of delegations is occasionally
leading to soft lockups. If the state manager was asked to reap the
expired delegations, it should scan only those filesystems that hold
delegations that need to be reaped.

Fixes: 7f156ef0bf45 ("NFSv4: Clean up nfs_delegation_reap_expired()")
Signed-off-by: Trond Myklebust <[email protected]>

show more ...

NFSv4: Avoid unnecessary scans of filesystems for returning delegations

The amount of looping through the list of delegations is occasionally
leading to soft lockups. If the state manager was asked

NFSv4: Avoid unnecessary scans of filesystems for returning delegations

The amount of looping through the list of delegations is occasionally
leading to soft lockups. If the state manager was asked to return
delegations asynchronously, it should only scan those filesystems that
hold delegations that need to be returned.

Fixes: af3b61bf6131 ("NFSv4: Clean up nfs_client_return_marked_delegations()")
Signed-off-by: Trond Myklebust <[email protected]>

show more ...

nfs: probe for LOCALIO when v4 client reconnects to server

Introduce nfs_local_probe_async() for the NFS client to initiate
if/when it reconnects with server. For NFSv4 it is a simple matter to
call

nfs: probe for LOCALIO when v4 client reconnects to server

Introduce nfs_local_probe_async() for the NFS client to initiate
if/when it reconnects with server. For NFSv4 it is a simple matter to
call nfs_local_probe_async() from nfs4_do_reclaim (during NFSv4
grace).

Signed-off-by: Mike Snitzer <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

nfs/localio: remove redundant code and simplify LOCALIO enablement

Remove nfs_local_enable and nfs_local_disable, instead use
nfs_localio_enable_client and nfs_localio_disable_client.

Discontinue u

nfs/localio: remove redundant code and simplify LOCALIO enablement

Remove nfs_local_enable and nfs_local_disable, instead use
nfs_localio_enable_client and nfs_localio_disable_client.

Discontinue use of the NFS_CS_LOCAL_IO bit in the nfs_client struct's
cl_flags to reflect that LOCALIO is enabled; instead just test if the
net member of the nfs_uuid_t struct is set.

Also remove NFS_CS_LOCAL_IO.

Lastly, remove trace_nfs_local_enable and trace_nfs_local_disable
because comparable traces are available from nfs_localio.ko.

Suggested-by: NeilBrown <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

nfs_common: move localio_lock to new lock member of nfs_uuid_t

Remove cl_localio_lock from 'struct nfs_client' in favor of adding a
lock to the nfs_uuid_t struct (which is embedded in each nfs_clien

nfs_common: move localio_lock to new lock member of nfs_uuid_t

Remove cl_localio_lock from 'struct nfs_client' in favor of adding a
lock to the nfs_uuid_t struct (which is embedded in each nfs_client).

Push nfs_local_{enable,disable} implementation down to nfs_common.
Those methods now call nfs_localio_{enable,disable}_client.

This allows implementing nfs_localio_invalidate_clients in terms of
nfs_localio_disable_client.

Signed-off-by: Mike Snitzer <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

NFSv4: Prevent NULL-pointer dereference in nfs42_complete_copies()

On the node of an NFS client, some files saved in the mountpoint of the
NFS server were copied to another location of the same NFS

NFSv4: Prevent NULL-pointer dereference in nfs42_complete_copies()

On the node of an NFS client, some files saved in the mountpoint of the
NFS server were copied to another location of the same NFS server.
Accidentally, the nfs42_complete_copies() got a NULL-pointer dereference
crash with the following syslog:

[232064.838881] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232064.839360] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232066.588183] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
[232066.588586] Mem abort info:
[232066.588701] ESR = 0x0000000096000007
[232066.588862] EC = 0x25: DABT (current EL), IL = 32 bits
[232066.589084] SET = 0, FnV = 0
[232066.589216] EA = 0, S1PTW = 0
[232066.589340] FSC = 0x07: level 3 translation fault
[232066.589559] Data abort info:
[232066.589683] ISV = 0, ISS = 0x00000007
[232066.589842] CM = 0, WnR = 0
[232066.589967] user pgtable: 64k pages, 48-bit VAs, pgdp=00002000956ff400
[232066.590231] [0000000000000058] pgd=08001100ae100003, p4d=08001100ae100003, pud=08001100ae100003, pmd=08001100b3c00003, pte=0000000000000000
[232066.590757] Internal error: Oops: 96000007 [#1] SMP
[232066.590958] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm vhost_net vhost vhost_iotlb tap tun ipt_rpfilter xt_multiport ip_set_hash_ip ip_set_hash_net xfrm_interface xfrm6_tunnel tunnel4 tunnel6 esp4 ah4 wireguard libcurve25519_generic veth xt_addrtype xt_set nf_conntrack_netlink ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_bitmap_port ip_set_hash_ipport dummy ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs iptable_filter sch_ingress nfnetlink_cttimeout vport_gre ip_gre ip_tunnel gre vport_geneve geneve vport_vxlan vxlan ip6_udp_tunnel udp_tunnel openvswitch nf_conncount dm_round_robin dm_service_time dm_multipath xt_nat xt_MASQUERADE nft_chain_nat nf_nat xt_mark xt_conntrack xt_comment nft_compat nft_counter nf_tables nfnetlink ocfs2 ocfs2_nodemanager ocfs2_stackglue iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ipmi_ssif nbd overlay 8021q garp mrp bonding tls rfkill sunrpc ext4 mbcache jbd2
[232066.591052] vfat fat cas_cache cas_disk ses enclosure scsi_transport_sas sg acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler ip_tables vfio_pci vfio_pci_core vfio_virqfd vfio_iommu_type1 vfio dm_mirror dm_region_hash dm_log dm_mod nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 br_netfilter bridge stp llc fuse xfs libcrc32c ast drm_vram_helper qla2xxx drm_kms_helper syscopyarea crct10dif_ce sysfillrect ghash_ce sysimgblt sha2_ce fb_sys_fops cec sha256_arm64 sha1_ce drm_ttm_helper ttm nvme_fc igb sbsa_gwdt nvme_fabrics drm nvme_core i2c_algo_bit i40e scsi_transport_fc megaraid_sas aes_neon_bs
[232066.596953] CPU: 6 PID: 4124696 Comm: 10.253.166.125- Kdump: loaded Not tainted 5.15.131-9.cl9_ocfs2.aarch64 #1
[232066.597356] Hardware name: Great Wall .\x93\x8e...RF6260 V5/GWMSSE2GL1T, BIOS T656FBE_V3.0.18 2024-01-06
[232066.597721] pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[232066.598034] pc : nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.598327] lr : nfs4_reclaim_open_state+0x12c/0x800 [nfsv4]
[232066.598595] sp : ffff8000f568fc70
[232066.598731] x29: ffff8000f568fc70 x28: 0000000000001000 x27: ffff21003db33000
[232066.599030] x26: ffff800005521ae0 x25: ffff0100f98fa3f0 x24: 0000000000000001
[232066.599319] x23: ffff800009920008 x22: ffff21003db33040 x21: ffff21003db33050
[232066.599628] x20: ffff410172fe9e40 x19: ffff410172fe9e00 x18: 0000000000000000
[232066.599914] x17: 0000000000000000 x16: 0000000000000004 x15: 0000000000000000
[232066.600195] x14: 0000000000000000 x13: ffff800008e685a8 x12: 00000000eac0c6e6
[232066.600498] x11: 0000000000000000 x10: 0000000000000008 x9 : ffff8000054e5828
[232066.600784] x8 : 00000000ffffffbf x7 : 0000000000000001 x6 : 000000000a9eb14a
[232066.601062] x5 : 0000000000000000 x4 : ffff70ff8a14a800 x3 : 0000000000000058
[232066.601348] x2 : 0000000000000001 x1 : 54dce46366daa6c6 x0 : 0000000000000000
[232066.601636] Call trace:
[232066.601749] nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.601998] nfs4_do_reclaim+0x1b8/0x28c [nfsv4]
[232066.602218] nfs4_state_manager+0x928/0x10f0 [nfsv4]
[232066.602455] nfs4_run_state_manager+0x78/0x1b0 [nfsv4]
[232066.602690] kthread+0x110/0x114
[232066.602830] ret_from_fork+0x10/0x20
[232066.602985] Code: 1400000d f9403f20 f9402e61 91016003 (f9402c00)
[232066.603284] SMP: stopping secondary CPUs
[232066.606936] Starting crashdump kernel...
[232066.607146] Bye!

Analysing the vmcore, we know that nfs4_copy_state listed by destination
nfs_server->ss_copies was added by the field copies in handle_async_copy(),
and we found a waiting copy process with the stack as:
PID: 3511963 TASK: ffff710028b47e00 CPU: 0 COMMAND: "cp"
#0 [ffff8001116ef740] __switch_to at ffff8000081b92f4
#1 [ffff8001116ef760] __schedule at ffff800008dd0650
#2 [ffff8001116ef7c0] schedule at ffff800008dd0a00
#3 [ffff8001116ef7e0] schedule_timeout at ffff800008dd6aa0
#4 [ffff8001116ef860] __wait_for_common at ffff800008dd166c
#5 [ffff8001116ef8e0] wait_for_completion_interruptible at ffff800008dd1898
#6 [ffff8001116ef8f0] handle_async_copy at ffff8000055142f4 [nfsv4]
#7 [ffff8001116ef970] _nfs42_proc_copy at ffff8000055147c8 [nfsv4]
#8 [ffff8001116efa80] nfs42_proc_copy at ffff800005514cf0 [nfsv4]
#9 [ffff8001116efc50] __nfs4_copy_file_range.constprop.0 at ffff8000054ed694 [nfsv4]

The NULL-pointer dereference was due to nfs42_complete_copies() listed
the nfs_server->ss_copies by the field ss_copies of nfs4_copy_state.
So the nfs4_copy_state address ffff0100f98fa3f0 was offset by 0x10 and
the data accessed through this pointer was also incorrect. Generally,
the ordered list nfs4_state_owner->so_states indicate open(O_RDWR) or
open(O_WRITE) states are reclaimed firstly by nfs4_reclaim_open_state().
When destination state reclaim is failed with NFS_STATE_RECOVERY_FAILED
and copies are not deleted in nfs_server->ss_copies, the source state
may be passed to the nfs42_complete_copies() process earlier, resulting
in this crash scene finally. To solve this issue, we add a list_head
nfs_server->ss_src_copies for a server-to-server copy specially.

Fixes: 0e65a32c8a56 ("NFS: handle source server reboot")
Signed-off-by: Yanjun Zhang <[email protected]>
Reviewed-by: Trond Myklebust <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

nfs: add LOCALIO support

Add client support for bypassing NFS for localhost reads, writes, and
commits. This is only useful when the client and the server are
running on the same host.

nfs_local_pr

nfs: add LOCALIO support

Add client support for bypassing NFS for localhost reads, writes, and
commits. This is only useful when the client and the server are
running on the same host.

nfs_local_probe() is stubbed out, later commits will enable client and
server handshake via a Linux-only LOCALIO auxiliary RPC protocol.

This has dynamic binding with the nfsd module (via nfs_localio module
which is part of nfs_common). LOCALIO will only work if nfsd is
already loaded.

The "localio_enabled" nfs kernel module parameter can be used to
disable and enable the ability to use LOCALIO support.

CONFIG_NFS_LOCALIO enables NFS client support for LOCALIO.

Lastly, LOCALIO uses an nfsd_file to initiate all IO. To make proper
use of nfsd_file (and nfsd's filecache) its lifetime (duration before
nfsd_file_put is called) must extend until after commit, read and
write operations. So rather than immediately drop the nfsd_file
reference in nfs_local_open_fh(), that doesn't happen until
nfs_local_pgio_release() for read/write and not until
nfs_local_release_commit_data() for commit. The same applies to the
reference held on nfsd's nn->nfsd_serv. Both objects' lifetimes and
associated references are managed through calls to
nfs_to->nfsd_file_put_local().

Signed-off-by: Weston Andros Adamson <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
Co-developed-by: Mike Snitzer <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>
Signed-off-by: NeilBrown <[email protected]> # nfs_open_local_fh
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

nfs: add 'noalignwrite' option for lock-less 'lost writes' prevention

There are some applications that write to predefined non-overlapping
file offsets from multiple clients and therefore don't need

nfs: add 'noalignwrite' option for lock-less 'lost writes' prevention

There are some applications that write to predefined non-overlapping
file offsets from multiple clients and therefore don't need to rely on
file locking. However, if these applications want non-aligned offsets
and sizes they need to either use locks or risk data corruption, as the
NFS client defaults to extending writes to whole pages.

This commit adds a new mount option `noalignwrite`, which allows to turn
that off and avoid the need of locking, as long as these applications
don't overlap on offsets.

Signed-off-by: Dan Aloni <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Reviewed-by: Sagi Grimberg <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

nfs: simplify and guarantee owner uniqueness.

I have evidence of an Linux NFS client getting NFS4ERR_BAD_SEQID to a
v4.0 LOCK request to a Linux server (which had fixed the problem with
RELEASE_LOCK

nfs: simplify and guarantee owner uniqueness.

I have evidence of an Linux NFS client getting NFS4ERR_BAD_SEQID to a
v4.0 LOCK request to a Linux server (which had fixed the problem with
RELEASE_LOCKOWNER bug fixed).
The LOCK request presented a "new" lock owner so there are two seq ids
in the request: that for the open file, and that for the new lock.
Given the context I am confident that the new lock owner was reported to
have the wrong seqid. As lock owner identifiers are reused, the server
must still have a lock owner active which the client thinks is no longer
active.

I wasn't able to determine a root-cause but the simplest fix seems to be
to ensure lock owners are always unique much as open owners are (thanks
to a time stamp). The easiest way to ensure uniqueness is with a 64bit
counter for each server. That will never cycle (if updated once a
nanosecond the last 584 years. A single NFS server would not handle
open/lock requests nearly that fast, and a Linux node is unlikely to
have an uptime approaching that).

This patch removes the 2 ida and instead uses a per-server
atomic64_t to provide uniqueness.

Note that the lock owner already encodes the id as 64 bits even though
it is a 32bit value. So changing to a 64bit value does not change the
encoding of the lock owner. The open owner encoding is now 4 bytes
larger.

Signed-off-by: NeilBrown <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

nfs: Block on write congestion

Commit 6df25e58532b ("nfs: remove reliance on bdi congestion")
introduced NFS-private solution for limiting number of writes
outstanding against a particular server. U

nfs: Block on write congestion

Commit 6df25e58532b ("nfs: remove reliance on bdi congestion")
introduced NFS-private solution for limiting number of writes
outstanding against a particular server. Unlike previous bdi congestion
this algorithm actually works and limits number of outstanding writeback
pages to nfs_congestion_kb which scales with amount of client's memory
and is capped at 256 MB. As a result some workloads such as random
buffered writes over NFS got slower (from ~170 MB/s to ~126 MB/s). The
fio command to reproduce is:

fio --direct=0 --ioengine=sync --thread --invalidate=1 --group_reporting=1
--runtime=300 --fallocate=posix --ramp_time=10 --new_group --rw=randwrite
--size=64256m --numjobs=4 --bs=4k --fsync_on_close=1 --end_fsync=1

This happens because the client sends ~256 MB worth of dirty pages to
the server and any further background writeback request is ignored until
the number of writeback pages gets below the threshold of 192 MB. By the
time this happens and clients decides to trigger another round of
writeback, the server often has no pages to write and the disk is idle.

To fix this problem and make the client react faster to eased congestion
of the server by blocking waiting for congestion to resolve instead of
aborting writeback. This improves the random 4k buffered write
throughput to 184 MB/s.

Reviewed-by: Sagi Grimberg <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Jan Kara <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

NFSv4/pNFS: Do layout state recovery upon reboot

Some pNFS implementations, such as flexible files, want the client to
send the layout stats and layout errors that may have incurred while the
metada

NFSv4/pNFS: Do layout state recovery upon reboot

Some pNFS implementations, such as flexible files, want the client to
send the layout stats and layout errors that may have incurred while the
metadata server was booting. To do so, the client sends a layoutreturn
with an all-zero stateid while the server is in grace during reboot
recovery.

Signed-off-by: Trond Myklebust <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

NFSv4: Detect support for OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION

If the server supports the NFSv4.2 protocol extension to optimise away
returning a stateid when it returns a delegation, then we

NFSv4: Detect support for OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION

If the server supports the NFSv4.2 protocol extension to optimise away
returning a stateid when it returns a delegation, then we cache that
information in another capability flag.

Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Lance Shelton <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

NFSv4: Add a capability for delegated attributes

Cache whether or not the server may have support for delegated
attributes in a capability flag.

Signed-off-by: Trond Myklebust <trond.myklebust@prim

NFSv4: Add a capability for delegated attributes

Cache whether or not the server may have support for delegated
attributes in a capability flag.

Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Lance Shelton <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

nfs: fix UAF on pathwalk running into umount

NFS ->d_revalidate(), ->permission() and ->get_link() need to access
some parts of nfs_server when called in RCU mode:
server->flags
server->caps
*(se

nfs: fix UAF on pathwalk running into umount

NFS ->d_revalidate(), ->permission() and ->get_link() need to access
some parts of nfs_server when called in RCU mode:
server->flags
server->caps
*(server->io_stats)
and, worst of all, call
server->nfs_client->rpc_ops->have_delegation
(the last one - as NFS_PROTO(inode)->have_delegation()). We really
don't want to RCU-delay the entire nfs_free_server() (it would have
to be done with schedule_work() from RCU callback, since it can't
be made to run from interrupt context), but actual freeing of
nfs_server and ->io_stats can be done via call_rcu() just fine.
nfs_client part is handled simply by making nfs_free_client() use
kfree_rcu().

Acked-by: Christian Brauner <[email protected]>
Signed-off-by: Al Viro <[email protected]>

show more ...

NFSv4: fairly test all delegations on a SEQ4_ revocation

When the client is required to use TEST_STATEID to discover which
delegation(s) have been revoked, it may continually test delegations at the

NFSv4: fairly test all delegations on a SEQ4_ revocation

When the client is required to use TEST_STATEID to discover which
delegation(s) have been revoked, it may continually test delegations at the
head of the list if the server continues to be unsatisfied and send
SEQ4_STATUS_RECALLABLE_STATE_REVOKED. For a large number of delegations
this behavior is prone to live-lock because the client may never be able to
test and free revoked state at the end of the list since the
SEQ4_STATUS_RECALLABLE_STATE_REVOKED will cause us to flag delegations at
the head of the list to be tested. This problem is further exacerbated by
the state manager's willingness to be scheduled out on a busy system while
testing the list of delegations.

Keep a generation counter for each attempt to test all delegations, and
skip delegations that have already been tested in the current pass.

Signed-off-by: Benjamin Coddington <[email protected]>
Tested-by: Torkil Svensgaard <[email protected]>
Tested-by: Ruben Vestergaard <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>

show more ...

NFSv4.1: fix pnfs MDS=DS session trunking

Currently, when GETDEVICEINFO returns multiple locations where each
is a different IP but the server's identity is same as MDS, then
nfs4_set_ds_client() fi

NFSv4.1: fix pnfs MDS=DS session trunking

Currently, when GETDEVICEINFO returns multiple locations where each
is a different IP but the server's identity is same as MDS, then
nfs4_set_ds_client() finds the existing nfs_client structure which
has the MDS's max_connect value (and if it's 1), then the 1st IP
on the DS's list will get dropped due to MDS trunking rules. Other
IPs would be added as they fall under the pnfs trunking rules.

For the list of IPs the 1st goes thru calling nfs4_set_ds_client()
which will eventually call nfs4_add_trunk() and call into
rpc_clnt_test_and_add_xprt() which has the check for MDS trunking.
The other IPs (after the 1st one), would call rpc_clnt_add_xprt()
which doesn't go thru that check.

nfs4_add_trunk() is called when MDS trunking is happening and it
needs to enforce the usage of max_connect mount option of the
1st mount. However, this shouldn't be applied to pnfs flow.

Instead, this patch proposed to treat MDS=DS as DS trunking and
make sure that MDS's max_connect limit does not apply to the
1st IP returned in the GETDEVICEINFO list. It does so by
marking the newly created client with a new flag NFS_CS_PNFS
which then used to pass max_connect value to use into the
rpc_clnt_test_and_add_xprt() instead of the existing rpc
client's max_connect value set by the MDS connection.

For example, mount was done without max_connect value set
so MDS's rpc client has cl_max_connect=1. Upon calling into
rpc_clnt_test_and_add_xprt() and using rpc client's value,
the caller passes in max_connect value which is previously
been set in the pnfs path (as a part of handling
GETDEVICEINFO list of IPs) in nfs4_set_ds_client().

However, when NFS_CS_PNFS flag is not set and we know we
are doing MDS trunking, comparing a new IP of the same
server, we then set the max_connect value to the
existing MDS's value and pass that into
rpc_clnt_test_and_add_xprt().

Fixes: dc48e0abee24 ("SUNRPC enforce creation of no more than max_connect xprts")
Signed-off-by: Olga Kornievskaia <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

show more ...

NFS: add sysfs shutdown knob

Within each nfs_server sysfs tree, add an entry named "shutdown". Writing
1 to this file will set the cl_shutdown bit on the rpc_clnt structs
associated with that mount

NFS: add sysfs shutdown knob

Within each nfs_server sysfs tree, add an entry named "shutdown". Writing
1 to this file will set the cl_shutdown bit on the rpc_clnt structs
associated with that mount. If cl_shutdown is set, the task scheduler
immediately returns -EIO for new tasks.

Signed-off-by: Benjamin Coddington <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>

show more ...

NFS: add superblock sysfs entries

Create a sysfs directory for each mount that corresponds to the mount's
nfs_server struct. As the mount is being constructed, use the name
"server-n", but rename i

NFS: add superblock sysfs entries

Create a sysfs directory for each mount that corresponds to the mount's
nfs_server struct. As the mount is being constructed, use the name
"server-n", but rename it to the "MAJOR:MINOR" of the mount after assigning
a device_id. The rename approach allows us to populate the mount's directory
with links to the various rpc_client objects during the mount's
construction. The naming convention (MAJOR:MINOR) can be used to reference
a particular NFS mount's sysfs tree.

Signed-off-by: Benjamin Coddington <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>

show more ...

NFS: Have struct nfs_client carry a TLS policy field

The new field is used to match struct nfs_clients that have the same
TLS policy setting.

Signed-off-by: Chuck Lever <[email protected]>
Rev

NFS: Have struct nfs_client carry a TLS policy field

The new field is used to match struct nfs_clients that have the same
TLS policy setting.

Signed-off-by: Chuck Lever <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>

show more ...