The 'cred_unused' list, that is traversed by rpcauth_cache_shrinker is
ordered by time. If we hit a credential that is under the 60 second garbage
collection moratorium, we should exit because we know at that point that
all successive credentials are subject to the same moratorium...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Under some circumstances, put_rpccred() can end up allocating memory, so
check the gfp_mask to prevent deadlocks.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Don't want to evict a credential if cred->cr_expire == jiffies, since that
means that it was just placed on the cred_unused list. We therefore need to
use time_in_range() rather than time_in_range_open().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is possible for rpcauth_destroy_credcache() to cause the rpc credentials
to be unhashed while put_rpccred is waiting for the rpc_credcache_lock on
another cpu. Should this happen, then we can end up calling
hlist_del_rcu(&cred->cr_hash) a second time in put_rpccred, thus causing
list corruption.
Should the credential actually be hashed, it is also possible for
rpcauth_lookup_credcache to find and reference it before we get round to
unhashing it. In this case, the call to rpcauth_unhash_cred will fail, and
so we should just exit without destroying the cred.
Reported-by: Neil Brown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Not including net/atm/
Compiled tested x86 allyesconfig only
Added a > 80 column line or two, which I ignored.
Existing checkpatch plaints willfully, cheerfully ignored.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise, the upcall is going to be synchronous, which may not be what the
caller wants...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Hi.
I've been looking at a bugzilla which describes a problem where
a customer was advised to use either the "noac" or "actimeo=0"
mount options to solve a consistency problem that they were
seeing in the file attributes. It turned out that this solution
did not work reliably for them because sometimes, the local
attribute cache was believed to be valid and not timed out.
(With an attribute cache timeout of 0, the cache should always
appear to be timed out.)
In looking at this situation, it appears to me that the problem
is that the attribute cache timeout code has an off-by-one
error in it. It is assuming that the cache is valid in the
region, [read_cache_jiffies, read_cache_jiffies + attrtimeo]. The
cache should be considered valid only in the region,
[read_cache_jiffies, read_cache_jiffies + attrtimeo). With this
change, the options, "noac" and "actimeo=0", work as originally
expected.
This problem was previously addressed by special casing the
attrtimeo == 0 case. However, since the problem is only an off-
by-one error, the cleaner solution is address the off-by-one
error and thus, not require the special case.
Thanx...
ps
Signed-off-by: Peter Staubach <staubach@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Somehow, this escaped the previous purge. There should be no need to keep
any extra locks in the XDR callbacks.
The NFS client XDR code only writes into private objects, whereas all reads
of shared objects are confined to fields that do not change, such as
filehandles...
Ditto for lockd, the NFSv2/v3 client mount code, and rpcbind.
The nfsd XDR code may require the BKL, but since it does a synchronous RPC
call from a thread that already holds the lock, that issue is moot.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Wrap current->cred and a few other accessors to hide their actual
implementation.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Separate the task security context from task_struct. At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.
Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.
With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.
Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
We have to be careful when we try to unhash the credential in
put_rpccred(), because we're not holding the credcache lock, so the call to
rpcauth_unhash_cred() may fail if someone else has looked the cred up, and
obtained a reference to it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We need to make sure that we don't remove creds from the cred_unused list
if they are still under the moratorium, or else they will never get
garbage collected.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Some code here depends on CONFIG_KMOD to not try to load
protocol modules or similar, replace by CONFIG_MODULES
where more than just request_module depends on CONFIG_KMOD
and and also use try_then_request_module in ebtables.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The NFSv4 protocol allows clients to negotiate security protocols on the
fly in the case where an administrator on the server changes the export
settings and/or in the case where we may have a filesystem migration event.
Instead of having the NFS client code cache credentials that are tied to a
particular AUTH method it is therefore preferable to have a generic credential
that can be converted into whatever AUTH is in use by the RPC client when
the read/write/sillyrename/... is put on the wire.
We do this by means of the new "generic" credential, which basically just
caches the minimal information that is needed to look up an RPCSEC_GSS,
AUTH_SYS, or AUTH_NULL credential.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We need the ability to treat 'generic' creds specially, since they want to
bind instances of the auth cred instead of binding themselves.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add an rpc credential that is not tied to any particular auth mechanism,
but that can be cached by NFS, and later used to look up a cred for
whichever auth mechanism that turns out to be valid when the RPC call is
being made.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The current RPCAUTH_LOOKUP_ROOTCREDS flag only works for AUTH_SYS
authentication, and then only as a special case in the code. This patch
removes the auth_sys special casing, and replaces it with generic code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits)
Remove commented-out code copied from NFS
NFS: Switch from intr mount option to TASK_KILLABLE
Add wait_for_completion_killable
Add wait_event_killable
Add schedule_timeout_killable
Use mutex_lock_killable in vfs_readdir
Add mutex_lock_killable
Use lock_page_killable
Add lock_page_killable
Add fatal_signal_pending
Add TASK_WAKEKILL
exit: Use task_is_*
signal: Use task_is_*
sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL
ptrace: Use task_is_*
power: Use task_is_*
wait: Use TASK_NORMAL
proc/base.c: Use task_is_*
proc/array.c: Use TASK_REPORT
perfmon: Use task_is_*
...
Fixed up conflicts in NFS/sunrpc manually..
The sunrpc client exports are not meant to be part of any official kernel
API: they can change at the drop of a hat. Mark them as internal functions
using EXPORT_SYMBOL_GPL.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Since every invocation of xdr encode or decode functions takes the BKL now,
there's a lot of redundant lock_kernel/unlock_kernel pairs that we can pull
out into a common function.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I can never remember what the function to register to receive VM pressure
is called. I have to trace down from __alloc_pages() to find it.
It's called "set_shrinker()", and it needs Your Help.
1) Don't hide struct shrinker. It contains no magic.
2) Don't allocate "struct shrinker". It's not helpful.
3) Call them "register_shrinker" and "unregister_shrinker".
4) Call the function "shrink" not "shrinker".
5) Reduce the 17 lines of waffly comments to 13, but document it properly.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Chinner <dgc@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We don't need the BKL when wrapping and unwrapping; and experiments by Avishay
Traeger have found that permitting multiple encryption and decryption
operations to proceed in parallel can provide significant performance
improvements.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Avishay Traeger <atraeger@cs.sunysb.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We should almost always be deferencing the rpc_auth struct by means of the
credential's cr_auth field instead of the rpc_clnt->cl_auth anyway. Fix up
that historical mistake, and remove the macro that propagated it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The leak only affects the RPCSEC_GSS caches, since they are the only ones
that are dynamically allocated...
Rename the existing rpcauth_free_credcache() to rpcauth_clear_credcache()
in order to better describe its role, then add a new function
rpcauth_destroy_credcache() that actually frees the cache in addition to
clearing it out.
Also move the call to destroy the credcache in gss_destroy() to come before
the rpc upcall pipe is unlinked.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The tk_pid field is an unsigned short. The proper print format specifier for
that type is %5u, not %4d.
Also clean up some miscellaneous print formatting nits.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
pure s/u32/__be32/
[AV: large part based on Alexey's patches]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a request_module call to rpcauth_create which will try
to auto-load the kernel module for the requested authentication flavor.
For kernels with modular sunrpc, this reduces the admin overhead for
the user.
Signed-off-by: Olaf Kirch <okir@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This fixes a bug whereby if two processes try to look up the same auth_gss
credential, they may end up creating two creds, and triggering two upcalls
because the upcall is performed before the credential is added to the
credcache.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When we look up a new cred in the auth_gss downcall so that we can stuff
the credcache, we do not want that lookup to queue up an upcall in order
to initialise it. To do an upcall here not only redundant, but since we
are already holding the inode->i_mutex, it will trigger a lock recursion.
This patch allows rpcauth cache searches to indicate that they can cope
with uninitialised credentials.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
