xprtrdma needs to allocate the Call and Reply buffers separately.
TBH, the reliance on using a single buffer for the pair of XDR
buffers is transport implementation-specific.
Transports that want to allocate separate Call and Reply buffers
will ignore the "size" argument anyway. Don't bother passing it.
The buf_alloc method can't return two pointers. Instead, make the
method's return value an error code, and set the rq_buffer pointer
in the method itself.
This gives call_allocate an opportunity to terminate an RPC instead
of looping forever when a permanent problem occurs. If a request is
just bogus, or the transport is in a state where it can't allocate
resources for any request, there needs to be a way to kill the RPC
right there and not loop.
This immediately fixes a rare problem in the backchannel send path,
which loops if the server happens to send a CB request whose
call+reply size is larger than a page (which it shouldn't do yet).
One more issue: looks like xprt_inject_disconnect was incorrectly
placed in the failure path in call_allocate. It needs to be in the
success path, as it is for other call-sites.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: there is some XDR initialization logic that is common
to the forward channel and backchannel. Move it to an XDR header
so it can be shared.
rpc_rqst::rq_buffer points to a buffer containing big-endian data.
Update its annotation as part of the clean up.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: r_xprt is already available everywhere these macros are
invoked, so just dereference that directly.
RPCRDMA_INLINE_PAD_VALUE is no longer used, so it can simply be
removed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Use a setup function to call into the NFS layer to test an rpc_xprt
for session trunking so as to not leak the rpc_xprt_switch into
the nfs layer.
Search for the address in the rpc_xprt_switch first so as not to
put an unnecessary EXCHANGE_ID on the wire.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Give the NFS layer access to the rpc_xprt_switch_add_xprt function
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Give the NFS layer access to the xprt_switch_put function
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
rpc_task_set_client is only called from rpc_run_task after
rpc_new_task and rpc_task_release_client is not needed as the
task is new.
When called from rpc_new_task, rpc_task_set_client also removed the
assigned rpc_xprt which is not desired.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The variable `err` is not used anywhere and just returns the
predefined value `0` at the end of the function. Hence, remove the
variable and return 0 explicitly.
Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
An RPC can terminate before its reply arrives, if a credential
problem or a soft timeout occurs. After this happens, xprtrdma
reports it is out of Receive buffers.
A Receive buffer is posted before each RPC is sent, and returned to
the buffer pool when a reply is received. If no reply is received
for an RPC, that Receive buffer remains posted. But xprtrdma tries
to post another when the next RPC is sent.
If this happens a few dozen times, there are no receive buffers left
to be posted at send time. I don't see a way for a transport
connection to recover at that point, and it will spit warnings and
unnecessarily delay RPCs on occasion for its remaining lifetime.
Commit 1e465fd4ff ("xprtrdma: Replace send and receive arrays")
removed a little bit of logic to detect this case and not provide
a Receive buffer so no more buffers are posted, and then transport
operation continues correctly. We didn't understand what that logic
did, and it wasn't commented, so it was removed as part of the
overhaul to support backchannel requests.
Restore it, but be wary of the need to keep extra Receives posted
to deal with backchannel requests.
Fixes: 1e465fd4ff ("xprtrdma: Replace send and receive arrays")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Receive buffer exhaustion, if it were to actually occur, would be
catastrophic. However, when there are no reply buffers to post, that
means all of them have already been posted and are waiting for
incoming replies. By design, there can never be more RPCs in flight
than there are available receive buffers.
A receive buffer can be left posted after an RPC exits without a
received reply; say, due to a credential problem or a soft timeout.
This does not result in fewer posted receive buffers than there are
pending RPCs, and there is already logic in xprtrdma to deal
appropriately with this case.
It also looks like the "+ 2" that was removed was accidentally
accommodating the number of extra receive buffers needed for
receiving backchannel requests. That will need to be addressed by
another patch.
Fixes: 3d4cf35bd4 ("xprtrdma: Reply buffer exhaustion can be...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The commit f9b2ee714c ("SUNRPC: Move UDP receive data path
into a workqueue context"), as a side effect, moved the
skb_free_datagram() call outside the scope of the related socket
lock, but UDP sockets require such lock to be held for proper
memory accounting.
Fix it by replacing skb_free_datagram() with
skb_free_datagram_locked().
Fixes: f9b2ee714c ("SUNRPC: Move UDP receive data path into a workqueue context")
Reported-and-tested-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Using NFSv4.1 on RDMA should be safe, so broaden the new checks in
rpc_create().
WARN_ON_ONCE is used, matching most other WARN call sites in clnt.c.
Fixes: 39a9beab5a ("rpc: share one xps between all backchannels")
Fixes: d50039ea5e ("nfsd4/rpc: move backchannel create logic...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Highlights include:
- Stable patch from Olga to fix RPCSEC_GSS upcalls when the same user needs
multiple different security services (e.g. krb5i and krb5p).
- Stable patch to fix a regression introduced by the use of SO_REUSEPORT,
and that prevented the use of multiple different NFS versions to the
same server.
- TCP socket reconnection timer fixes.
- Patch from Neil to disable the use of IPv6 temporary addresses.
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Merge tag 'nfs-for-4.8-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Stable patch from Olga to fix RPCSEC_GSS upcalls when the same user
needs multiple different security services (e.g. krb5i and krb5p).
- Stable patch to fix a regression introduced by the use of
SO_REUSEPORT, and that prevented the use of multiple different NFS
versions to the same server.
- TCP socket reconnection timer fixes.
- Patch from Neil to disable the use of IPv6 temporary addresses"
* tag 'nfs-for-4.8-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Cap the transport reconnection timer at 1/2 lease period
NFSv4: Cleanup the setting of the nfs4 lease period
SUNRPC: Limit the reconnect backoff timer to the max RPC message timeout
SUNRPC: Fix reconnection timeouts
NFSv4.2: LAYOUTSTATS may return NFS4ERR_ADMIN/DELEG_REVOKED
SUNRPC: disable the use of IPv6 temporary addresses.
SUNRPC: allow for upcalls for same uid but different gss service
SUNRPC: Fix up socket autodisconnect
SUNRPC: Handle EADDRNOTAVAIL on connection failures
We don't want to miss a lease period renewal due to the TCP connection
failing to reconnect in a timely fashion. To ensure this doesn't happen,
cap the reconnection timer so that we retry the connection attempt
at least every 1/2 lease period.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When the connect attempt fails and backs off, we should start the clock
at the last connection attempt, not time at which we queue up the
reconnect job.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the net.ipv6.conf.*.use_temp_addr sysctl is set to '2',
then TCP connections over IPv6 will prefer a 'private' source
address.
These eventually expire and become invalid, typically after a week,
but the time is configurable.
When the local address becomes invalid the client will not be able to
receive replies from the server. Eventually the connection will timeout
or break and a new connection will be established, but this can take
half an hour (typically TCP connection break time).
RFC 4941, which describes private IPv6 addresses, acknowledges that some
applications might not work well with them and that the application may
explicitly a request non-temporary (i.e. "public") address.
I believe this is correct for SUNRPC clients. Without this change, a
client will occasionally experience a long delay if private addresses
have been enabled.
The privacy offered by private addresses is of little value for an NFS
server which requires client authentication.
For NFSv3 this will often not be a problem because idle connections are
closed after 5 minutes. For NFSv4 connections never go idle due to the
period RENEW (or equivalent) request.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It's possible to have simultaneous upcalls for the same UIDs but
different GSS service. In that case, we need to allow for the
upcall to gssd to proceed so that not the same context is used
by two different GSS services. Some servers lock the use of context
to the GSS service.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Trond made a change to the server's tcp logic that allows a fast
client to better take advantage of high bandwidth networks, but
may increase the risk that a single client could starve other
clients; a new sunrpc.svc_rpc_per_connection_limit parameter
should help mitigate this in the (hopefully unlikely) event this
becomes a problem in practice.
Tom Haynes added a minimal flex-layout pnfs server, which is of
no use in production for now--don't build it unless you're doing
client testing or further server development.
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Merge tag 'nfsd-4.8' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Highlights:
- Trond made a change to the server's tcp logic that allows a fast
client to better take advantage of high bandwidth networks, but may
increase the risk that a single client could starve other clients;
a new sunrpc.svc_rpc_per_connection_limit parameter should help
mitigate this in the (hopefully unlikely) event this becomes a
problem in practice.
- Tom Haynes added a minimal flex-layout pnfs server, which is of no
use in production for now--don't build it unless you're doing
client testing or further server development"
* tag 'nfsd-4.8' of git://linux-nfs.org/~bfields/linux: (32 commits)
nfsd: remove some dead code in nfsd_create_locked()
nfsd: drop unnecessary MAY_EXEC check from create
nfsd: clean up bad-type check in nfsd_create_locked
nfsd: remove unnecessary positive-dentry check
nfsd: reorganize nfsd_create
nfsd: check d_can_lookup in fh_verify of directories
nfsd: remove redundant zero-length check from create
nfsd: Make creates return EEXIST instead of EACCES
SUNRPC: Detect immediate closure of accepted sockets
SUNRPC: accept() may return sockets that are still in SYN_RECV
nfsd: allow nfsd to advertise multiple layout types
nfsd: Close race between nfsd4_release_lockowner and nfsd4_lock
nfsd/blocklayout: Make sure calculate signature/designator length aligned
xfs: abstract block export operations from nfsd layouts
SUNRPC: Remove unused callback xpo_adjust_wspace()
SUNRPC: Change TCP socket space reservation
SUNRPC: Add a server side per-connection limit
SUNRPC: Micro optimisation for svc_data_ready
SUNRPC: Call the default socket callbacks instead of open coding
SUNRPC: lock the socket while detaching it
...
Ensure that we don't forget to set up the disconnection timer for the
case when a connect request is fulfilled after the RPC request that
initiated it has timed out or been interrupted.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This modification is useful for debugging issues that happen while
the socket is being initialised.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We're seeing traces of the following form:
[10952.396347] svc: transport ffff88042ba4a 000 dequeued, inuse=2
[10952.396351] svc: tcp_accept ffff88042ba4 a000 sock ffff88042a6e4c80
[10952.396362] nfsd: connect from 10.2.6.1, port=187
[10952.396364] svc: svc_setup_socket ffff8800b99bcf00
[10952.396368] setting up TCP socket for reading
[10952.396370] svc: svc_setup_socket created ffff8803eb10a000 (inet ffff88042b75b800)
[10952.396373] svc: transport ffff8803eb10a000 put into queue
[10952.396375] svc: transport ffff88042ba4a000 put into queue
[10952.396377] svc: server ffff8800bb0ec000 waiting for data (to = 3600000)
[10952.396380] svc: transport ffff8803eb10a000 dequeued, inuse=2
[10952.396381] svc_recv: found XPT_CLOSE
[10952.396397] svc: svc_delete_xprt(ffff8803eb10a000)
[10952.396398] svc: svc_tcp_sock_detach(ffff8803eb10a000)
[10952.396399] svc: svc_sock_detach(ffff8803eb10a000)
[10952.396412] svc: svc_sock_free(ffff8803eb10a000)
i.e. an immediate close of the socket after initialisation.
The culprit appears to be the test at the end of svc_tcp_init, which
checks if the newly created socket is in the TCP_ESTABLISHED state,
and immediately closes it if not. The evidence appears to suggest that
the socket might still be in the SYN_RECV state at this time.
The fix is to check for both states, and then to add a check in
svc_tcp_state_change() to ensure we don't close the socket when
it transitions into TCP_ESTABLISHED.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If the connect attempt immediately fails with an EADDRNOTAVAIL error, then
that means our choice of source port number was bad.
This error is expected when we set the SO_REUSEPORT socket option and we
have 2 sockets sharing the same source and destination address and port
combinations.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fixes: 402e23b4ed ("SUNRPC: Fix stupid typo in xs_sock_set_reuseport")
Cc: stable@vger.kernel.org # v4.0+
Highlights include:
Stable bugfixes:
- nfs: don't create zero-length requests
- Several LAYOUTGET bugfixes
Features:
- Several performance related features
- More aggressive caching when we can rely on close-to-open cache
consistency
- Remove serialisation of O_DIRECT reads and writes
- Optimise several code paths to not flush to disk unnecessarily. However
allow for the idiosyncracies of pNFS for those layout types that need
to issue a LAYOUTCOMMIT before the metadata can be updated on the server.
- SUNRPC updates to the client data receive path
- pNFS/SCSI support RH/Fedora dm-mpath device nodes
- pNFS files/flexfiles can now use unprivileged ports when the generic NFS
mount options allow it.
Bugfixes:
- Don't use RDMA direct data placement together with data integrity or
privacy security flavours
- Remove the RDMA ALLPHYSICAL memory registration mode as it has potential
security holes.
- Several layout recall fixes to improve NFSv4.1 protocol compliance.
- Fix an Oops in the pNFS files and flexfiles connection setup to the DS
- Allow retry of operations that used a returned delegation stateid
- Don't mark the inode as revalidated if a LAYOUTCOMMIT is outstanding
- Fix writeback races in nfs4_copy_range() and nfs42_proc_deallocate()
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Merge tag 'nfs-for-4.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable bugfixes:
- nfs: don't create zero-length requests
- several LAYOUTGET bugfixes
Features:
- several performance related features
- more aggressive caching when we can rely on close-to-open
cache consistency
- remove serialisation of O_DIRECT reads and writes
- optimise several code paths to not flush to disk unnecessarily.
However allow for the idiosyncracies of pNFS for those layout
types that need to issue a LAYOUTCOMMIT before the metadata can
be updated on the server.
- SUNRPC updates to the client data receive path
- pNFS/SCSI support RH/Fedora dm-mpath device nodes
- pNFS files/flexfiles can now use unprivileged ports when
the generic NFS mount options allow it.
Bugfixes:
- Don't use RDMA direct data placement together with data
integrity or privacy security flavours
- Remove the RDMA ALLPHYSICAL memory registration mode as
it has potential security holes.
- Several layout recall fixes to improve NFSv4.1 protocol
compliance.
- Fix an Oops in the pNFS files and flexfiles connection
setup to the DS
- Allow retry of operations that used a returned delegation
stateid
- Don't mark the inode as revalidated if a LAYOUTCOMMIT is
outstanding
- Fix writeback races in nfs4_copy_range() and
nfs42_proc_deallocate()"
* tag 'nfs-for-4.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (104 commits)
pNFS: Actively set attributes as invalid if LAYOUTCOMMIT is outstanding
NFSv4: Clean up lookup of SECINFO_NO_NAME
NFSv4.2: Fix warning "variable ‘stateids’ set but not used"
NFSv4: Fix warning "no previous prototype for ‘nfs4_listxattr’"
SUNRPC: Fix a compiler warning in fs/nfs/clnt.c
pNFS: Remove redundant smp_mb() from pnfs_init_lseg()
pNFS: Cleanup - do layout segment initialisation in one place
pNFS: Remove redundant stateid invalidation
pNFS: Remove redundant pnfs_mark_layout_returned_if_empty()
pNFS: Clear the layout metadata if the server changed the layout stateid
pNFS: Cleanup - don't open code pnfs_mark_layout_stateid_invalid()
NFS: pnfs_mark_matching_lsegs_return() should match the layout sequence id
pNFS: Do not set plh_return_seq for non-callback related layoutreturns
pNFS: Ensure layoutreturn acts as a completion for layout callbacks
pNFS: Fix CB_LAYOUTRECALL stateid verification
pNFS: Always update the layout barrier seqid on LAYOUTGET
pNFS: Always update the layout stateid if NFS_LAYOUT_INVALID_STID is set
pNFS: Clear the layout return tracking on layout reinitialisation
pNFS: LAYOUTRETURN should only update the stateid if the layout is valid
nfs: don't create zero-length requests
...
Pull userns vfs updates from Eric Biederman:
"This tree contains some very long awaited work on generalizing the
user namespace support for mounting filesystems to include filesystems
with a backing store. The real world target is fuse but the goal is
to update the vfs to allow any filesystem to be supported. This
patchset is based on a lot of code review and testing to approach that
goal.
While looking at what is needed to support the fuse filesystem it
became clear that there were things like xattrs for security modules
that needed special treatment. That the resolution of those concerns
would not be fuse specific. That sorting out these general issues
made most sense at the generic level, where the right people could be
drawn into the conversation, and the issues could be solved for
everyone.
At a high level what this patchset does a couple of simple things:
- Add a user namespace owner (s_user_ns) to struct super_block.
- Teach the vfs to handle filesystem uids and gids not mapping into
to kuids and kgids and being reported as INVALID_UID and
INVALID_GID in vfs data structures.
By assigning a user namespace owner filesystems that are mounted with
only user namespace privilege can be detected. This allows security
modules and the like to know which mounts may not be trusted. This
also allows the set of uids and gids that are communicated to the
filesystem to be capped at the set of kuids and kgids that are in the
owning user namespace of the filesystem.
One of the crazier corner casees this handles is the case of inodes
whose i_uid or i_gid are not mapped into the vfs. Most of the code
simply doesn't care but it is easy to confuse the inode writeback path
so no operation that could cause an inode write-back is permitted for
such inodes (aka only reads are allowed).
This set of changes starts out by cleaning up the code paths involved
in user namespace permirted mounts. Then when things are clean enough
adds code that cleanly sets s_user_ns. Then additional restrictions
are added that are possible now that the filesystem superblock
contains owner information.
These changes should not affect anyone in practice, but there are some
parts of these restrictions that are changes in behavior.
- Andy's restriction on suid executables that does not honor the
suid bit when the path is from another mount namespace (think
/proc/[pid]/fd/) or when the filesystem was mounted by a less
privileged user.
- The replacement of the user namespace implicit setting of MNT_NODEV
with implicitly setting SB_I_NODEV on the filesystem superblock
instead.
Using SB_I_NODEV is a stronger form that happens to make this state
user invisible. The user visibility can be managed but it caused
problems when it was introduced from applications reasonably
expecting mount flags to be what they were set to.
There is a little bit of work remaining before it is safe to support
mounting filesystems with backing store in user namespaces, beyond
what is in this set of changes.
- Verifying the mounter has permission to read/write the block device
during mount.
- Teaching the integrity modules IMA and EVM to handle filesystems
mounted with only user namespace root and to reduce trust in their
security xattrs accordingly.
- Capturing the mounters credentials and using that for permission
checks in d_automount and the like. (Given that overlayfs already
does this, and we need the work in d_automount it make sense to
generalize this case).
Furthermore there are a few changes that are on the wishlist:
- Get all filesystems supporting posix acls using the generic posix
acls so that posix_acl_fix_xattr_from_user and
posix_acl_fix_xattr_to_user may be removed. [Maintainability]
- Reducing the permission checks in places such as remount to allow
the superblock owner to perform them.
- Allowing the superblock owner to chown files with unmapped uids and
gids to something that is mapped so the files may be treated
normally.
I am not considering even obvious relaxations of permission checks
until it is clear there are no more corner cases that need to be
locked down and handled generically.
Many thanks to Seth Forshee who kept this code alive, and putting up
with me rewriting substantial portions of what he did to handle more
corner cases, and for his diligent testing and reviewing of my
changes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (30 commits)
fs: Call d_automount with the filesystems creds
fs: Update i_[ug]id_(read|write) to translate relative to s_user_ns
evm: Translate user/group ids relative to s_user_ns when computing HMAC
dquot: For now explicitly don't support filesystems outside of init_user_ns
quota: Handle quota data stored in s_user_ns in quota_setxquota
quota: Ensure qids map to the filesystem
vfs: Don't create inodes with a uid or gid unknown to the vfs
vfs: Don't modify inodes with a uid or gid unknown to the vfs
cred: Reject inodes with invalid ids in set_create_file_as()
fs: Check for invalid i_uid in may_follow_link()
vfs: Verify acls are valid within superblock's s_user_ns.
userns: Handle -1 in k[ug]id_has_mapping when !CONFIG_USER_NS
fs: Refuse uid/gid changes which don't map into s_user_ns
selinux: Add support for unprivileged mounts from user namespaces
Smack: Handle labels consistently in untrusted mounts
Smack: Add support for unprivileged mounts from user namespaces
fs: Treat foreign mounts as nosuid
fs: Limit file caps to the user namespace of the super block
userns: Remove the now unnecessary FS_USERNS_DEV_MOUNT flag
userns: Remove implicit MNT_NODEV fragility.
...
Fix the report:
net/sunrpc/clnt.c:2580:1: warning: ‘static’ is not at beginning of declaration [-Wold-style-declaration]
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The current min/max resvport settings are independently limited
by the entire range of allowed ports, so max_resvport can be
set to a port lower than min_resvport.
Prevent inversion of min/max values when set through sysfs and
module parameter by setting the limits dependent on each other.
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The current min/max resvport settings are independently limited
by the entire range of allowed ports, so max_resvport can be
set to a port lower than min_resvport.
Prevent inversion of min/max values when set through sysctl by
setting the limits dependent on each other.
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The range calculation for choosing the random reserved port will panic
with divide-by-zero when min_resvport == max_resvport, a range of one
port, not zero.
Fix the reserved port range calculation by adding one to the difference.
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Author: Frank Sorenson <sorenson@redhat.com>
Date: 2016-06-27 13:55:48 -0500
sunrpc: Fix bit count when setting hashtable size to power-of-two
The hashtable size is incorrectly calculated as the next higher
power-of-two when being set to a power-of-two. fls() returns the
bit number of the most significant set bit, with the least
significant bit being numbered '1'. For a power-of-two, fls()
will return a bit number which is one higher than the number of bits
required, leading to a hashtable which is twice the requested size.
In addition, the value of (1 << nbits) will always be at least num,
so the test will never be true.
Fix the hash table size calculation to correctly set hashtable
size, and eliminate the unnecessary check.
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
A generic_cred can be used to look up a unx_cred or a gss_cred, so it's
not really safe to use the the generic_cred->acred->ac_flags to store
the NO_CRKEY_TIMEOUT flag. A lookup for a unx_cred triggered while the
KEY_EXPIRE_SOON flag is already set will cause both NO_CRKEY_TIMEOUT and
KEY_EXPIRE_SOON to be set in the ac_flags, leaving the user associated
with the auth_cred to be in a state where they're perpetually doing 4K
NFS_FILE_SYNC writes.
This can be reproduced as follows:
1. Mount two NFS filesystems, one with sec=krb5 and one with sec=sys.
They do not need to be the same export, nor do they even need to be from
the same NFS server. Also, v3 is fine.
$ sudo mount -o v3,sec=krb5 server1:/export /mnt/krb5
$ sudo mount -o v3,sec=sys server2:/export /mnt/sys
2. As the normal user, before accessing the kerberized mount, kinit with
a short lifetime (but not so short that renewing the ticket would leave
you within the 4-minute window again by the time the original ticket
expires), e.g.
$ kinit -l 10m -r 60m
3. Do some I/O to the kerberized mount and verify that the writes are
wsize, UNSTABLE:
$ dd if=/dev/zero of=/mnt/krb5/file bs=1M count=1
4. Wait until you're within 4 minutes of key expiry, then do some more
I/O to the kerberized mount to ensure that RPC_CRED_KEY_EXPIRE_SOON gets
set. Verify that the writes are 4K, FILE_SYNC:
$ dd if=/dev/zero of=/mnt/krb5/file bs=1M count=1
5. Now do some I/O to the sec=sys mount. This will cause
RPC_CRED_NO_CRKEY_TIMEOUT to be set:
$ dd if=/dev/zero of=/mnt/sys/file bs=1M count=1
6. Writes for that user will now be permanently 4K, FILE_SYNC for that
user, regardless of which mount is being written to, until you reboot
the client. Renewing the kerberos ticket (assuming it hasn't already
expired) will have no effect. Grabbing a new kerberos ticket at this
point will have no effect either.
Move the flag to the auth->au_flags field (which is currently unused)
and rename it slightly to reflect that it's no longer associated with
the auth_cred->ac_flags. Add the rpc_auth to the arg list of
rpcauth_cred_key_to_expire and check the au_flags there too. Finally,
add the inode to the arg list of nfs_ctx_key_to_expire so we can
determine the rpc_auth to pass to rpcauth_cred_key_to_expire.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If there were less than 2 entries in the multipath list, then
xprt_iter_next_entry_multiple() would never advance beyond the
first entry, which is correct for round robin behaviour, but not
for the list iteration.
The end result would be infinite looping in rpc_clnt_iterate_for_each_xprt()
as we would never see the xprt == NULL condition fulfilled.
Reported-by: Oleg Drokin <green@linuxhacker.ru>
Fixes: 80b14d5e61 ("SUNRPC: Add a structure to track multiple transports")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The current server rpc tcp code attempts to predict how much writeable
socket space will be available to a given RPC call before accepting it
for processing. On a 40GigE network, we've found this throttles
individual clients long before the network or disk is saturated. The
server may handle more clients easily, but the bandwidth of individual
clients is still artificially limited.
Instead of trying (and failing) to predict how much writeable socket space
will be available to the RPC call, just fall back to the simple model of
deferring processing until the socket is uncongested.
This may increase the risk of fast clients starving slower clients; in
such cases, the previous patch allows setting a hard per-connection
limit.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Allow the user to limit the number of requests serviced through a single
connection, to help prevent faster clients from starving slower clients.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Don't call svc_xprt_enqueue() if the XPT_DATA flag is already set.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Rather than code up our own versions of the socket callbacks, just
call the defaults.
This also allows us to merge svc_udp_data_ready() and svc_tcp_data_ready().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Prevent callbacks from triggering while we're detaching the socket.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Dropping and/or deferring requests has an impact on performance. Let's
make sure we can trace those events.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a tracepoint to track when the processing of incoming RPC data gets
deferred due to out-of-space issues on the outgoing transport.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
GSS-Proxy doesn't produce very much debug logging at all. Printing out
the gss minor status will aid in troubleshooting if the
GSS_Accept_sec_context upcall fails.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Before commit 778be232a2 ("NFS do not find client in NFSv4
pg_authenticate"), the Linux callback server replied with
RPC_AUTH_ERROR / RPC_AUTH_BADCRED, instead of dropping the CB
request. Let's restore that behavior so the server has a chance to
do something useful about it, and provide a warning that helps
admins correct the problem.
Fixes: 778be232a2 ("NFS do not find client in NFSv4 ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
