current_cred() can only be changed by 'current', and
cred->group_info is never changed. If a new group_info is
needed, a new 'cred' is created.
Consequently it is always safe to access
current_cred()->group_info
without taking any further references.
So drop the refcounting and the incorrect rcu_dereference().
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The new flag RPCAUTH_LOOKUP_RCU to credential lookup avoids locking,
does not take a reference on the returned credential, and returns
-ECHILD if a simple lookup was not possible.
The returned value can only be used within an rcu_read_lock protected
region.
The main user of this is the new rpc_lookup_cred_nonblock() which
returns a pointer to the current credential which is only rcu-safe (no
ref-count held), and might return -ECHILD if allocation was required.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
In some cases where the credentials are not often reused, we may want
to limit their total number just in order to make the negative lookups
in the hash table more manageable.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
...and add an new rpc_auth function to call it when it exists. This
is only applicable for AUTH_GSS mechanisms, so we only specify this
for those sorts of credentials.
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fix nfs4_negotiate_security to create an rpc_clnt used to test each SECINFO
returned pseudoflavor. Check credential creation (and gss_context creation)
which is important for RPC_AUTH_GSS pseudoflavors which can fail for multiple
reasons including mis-configuration.
Don't call nfs4_negotiate in nfs4_submount as it was just called by
nfs4_proc_lookup_mountpoint (nfs4_proc_lookup_common)
Signed-off-by: Andy Adamson <andros@netapp.com>
[Trond: fix corrupt return value from nfs_find_best_sec()]
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Convert the remaining couple of random shrinkers in the tree to the new
API.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@openvz.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch provides the RPC layer helper functions to allow NFS to manage
data in the face of expired credentials - such as avoiding buffered WRITEs
and COMMITs when the gss context will expire before the WRITEs are flushed
and COMMITs are sent.
These helper functions enable checking the expiration of an underlying
credential key for a generic rpc credential, e.g. the gss_cred gss context
gc_expiry which for Kerberos is set to the remaining TGT lifetime.
A new rpc_authops key_timeout is only defined for the generic auth.
A new rpc_credops crkey_to_expire is only defined for the generic cred.
A new rpc_credops crkey_timeout is only defined for the gss cred.
Set a credential key expiry watermark, RPC_KEY_EXPIRE_TIMEO set to 240 seconds
as a default and can be set via a module parameter as we need to ensure there
is time for any dirty data to be flushed.
If key_timeout is called on a credential with an underlying credential key that
will expire within watermark seconds, we set the RPC_CRED_KEY_EXPIRE_SOON
flag in the generic_cred acred so that the NFS layer can clean up prior to
key expiration.
Checking a generic credential's underlying credential involves a cred lookup.
To avoid this lookup in the normal case when the underlying credential has
a key that is valid (before the watermark), a notify flag is set in
the generic credential the first time the key_timeout is called. The
generic credential then stops checking the underlying credential key expiry, and
the underlying credential (gss_cred) match routine then checks the key
expiration upon each normal use and sets a flag in the associated generic
credential only when the key expiration is within the watermark.
This in turn signals the generic credential key_timeout to perform the extra
credential lookup thereafter.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The clnt->cl_principal is being used exclusively to store the service
target name for RPCSEC_GSS/krb5 callbacks. Replace it with something that
is stored only in the RPCSEC_GSS-specific code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
RPC_AUTH_MAXFLAVOR is an invalid flavor, on purpose. Don't allow
any processing whatsoever if a caller passes it to rpcauth_create()
or rpcauth_get_gssinfo().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up. This matches a similar API for the client side, and
keeps ULP fingers out the of the GSS mech switch.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
A SECINFO reply may contain flavors whose kernel module is not
yet loaded by the client's kernel. A new RPC client API, called
rpcauth_get_pseudoflavor(), is introduced to do proper checking
for support of a security flavor.
When this API is invoked, the RPC client now tries to load the
module for each flavor first before performing the "is this
supported?" check. This means if a module is available on the
client, but has not been loaded yet, it will be loaded and
registered automatically when the SECINFO reply is processed.
The new API can take a full GSS tuple (OID, QoP, and service).
Previously only the OID and service were considered.
nfs_find_best_sec() is updated to verify all flavors requested in a
SECINFO reply, including AUTH_NULL and AUTH_UNIX. Previously these
two flavors were simply assumed to be supported without consulting
the RPC client.
Note that the replaced version of nfs_find_best_sec() can return
RPC_AUTH_MAXFLAVOR if the server returns a recognized OID but an
unsupported "service" value. nfs_find_best_sec() now returns
RPC_AUTH_UNIX in this case.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I'm not sure why, but the hlist for each entry iterators were conceived
list_for_each_entry(pos, head, member)
The hlist ones were greedy and wanted an extra parameter:
hlist_for_each_entry(tpos, pos, head, member)
Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.
Besides the semantic patch, there was some manual work required:
- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.
The semantic patch which is mostly the work of Peter Senna Tschudin is here:
@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
type T;
expression a,c,d,e;
identifier b;
statement S;
@@
-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>
[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In svcauth_unix introduce a helper unix_gid_hash as otherwise the
expresion to generate the hash value is just too long.
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Instead of (uid_t)0 use GLOBAL_ROOT_UID.
Instead of (gid_t)0 use GLOBAL_ROOT_GID.
Instead of (uid_t)-1 use INVALID_UID
Instead of (gid_t)-1 use INVALID_GID.
Instead of NOGROUP use INVALID_GID.
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
The gss_mech_list_pseudoflavors() function provides a list of
currently registered GSS pseudoflavors. This list does not include
any non-GSS flavors that have been registered with the RPC client.
nfs4_find_root_sec() currently adds these extra flavors by hand.
Instead, nfs4_find_root_sec() should be looking at the set of flavors
that have been explicitly registered via rpcauth_register(). And,
other areas of code will soon need the same kind of list that
contains all flavors the kernel currently knows about (see below).
Rather than cloning the open-coded logic in nfs4_find_root_sec() to
those new places, introduce a generic RPC function that generates a
full list of registered auth flavors and pseudoflavors.
A new rpc_authops method is added that lists a flavor's
pseudoflavors, if it has any. I encountered an interesting module
loader loop when I tried to get the RPC client to invoke
gss_mech_list_pseudoflavors() by name.
This patch is a pre-requisite for server trunking discovery, and a
pre-requisite for fixing up the in-kernel mount client to do better
automatic security flavor selection.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Semicolons are not necessary after switch/while/for/if braces
so remove them.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change each shrinker's API by consolidating the existing parameters into
shrink_control struct. This will simplify any further features added w/o
touching each file of shrinker.
[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: fix warning]
[kosaki.motohiro@jp.fujitsu.com: fix up new shrinker API]
[akpm@linux-foundation.org: fix xfs warning]
[akpm@linux-foundation.org: update gfs2]
Signed-off-by: Ying Han <yinghan@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that all client-side XDR decoder routines use xdr_streams, there
should be no need to support the legacy calling sequence [rpc_rqst *,
__be32 *, RPC res *] anywhere. We can construct an xdr_stream in the
generic RPC code, instead of in each decoder function.
This is a refactoring change. It should not cause different behavior.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Now that all client-side XDR encoder routines use xdr_streams, there
should be no need to support the legacy calling sequence [rpc_rqst *,
__be32 *, RPC arg *] anywhere. We can construct an xdr_stream in the
generic RPC code, instead of in each encoder function.
Also, all the client-side encoder functions return 0 now, making a
return value superfluous. Take this opportunity to convert them to
return void instead.
This is a refactoring change. It should not cause different behavior.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'for-2.6.37' of git://linux-nfs.org/~bfields/linux: (99 commits)
svcrpc: svc_tcp_sendto XPT_DEAD check is redundant
svcrpc: no need for XPT_DEAD check in svc_xprt_enqueue
svcrpc: assume svc_delete_xprt() called only once
svcrpc: never clear XPT_BUSY on dead xprt
nfsd4: fix connection allocation in sequence()
nfsd4: only require krb5 principal for NFSv4.0 callbacks
nfsd4: move minorversion to client
nfsd4: delay session removal till free_client
nfsd4: separate callback change and callback probe
nfsd4: callback program number is per-session
nfsd4: track backchannel connections
nfsd4: confirm only on succesful create_session
nfsd4: make backchannel sequence number per-session
nfsd4: use client pointer to backchannel session
nfsd4: move callback setup into session init code
nfsd4: don't cache seq_misordered replies
SUNRPC: Properly initialize sock_xprt.srcaddr in all cases
SUNRPC: Use conventional switch statement when reclassifying sockets
sunrpc/xprtrdma: clean up workqueue usage
sunrpc: Turn list_for_each-s into the ..._entry-s
...
Fix up trivial conflicts (two different deprecation notices added in
separate branches) in Documentation/feature-removal-schedule.txt
* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (67 commits)
SUNRPC: Cleanup duplicate assignment in rpcauth_refreshcred
nfs: fix unchecked value
Ask for time_delta during fsinfo probe
Revalidate caches on lock
SUNRPC: After calling xprt_release(), we must restart from call_reserve
NFSv4: Fix up the 'dircount' hint in encode_readdir
NFSv4: Clean up nfs4_decode_dirent
NFSv4: nfs4_decode_dirent must clear entry->fattr->valid
NFSv4: Fix a regression in decode_getfattr
NFSv4: Fix up decode_attr_filehandle() to handle the case of empty fh pointer
NFS: Ensure we check all allocation return values in new readdir code
NFS: Readdir plus in v4
NFS: introduce generic decode_getattr function
NFS: check xdr_decode for errors
NFS: nfs_readdir_filler catch all errors
NFS: readdir with vmapped pages
NFS: remove page size checking code
NFS: decode_dirent should use an xdr_stream
SUNRPC: Add a helper function xdr_inline_peek
NFS: remove readdir plus limit
...
On Wed, 29 Sep 2010 14:02:38 +1000 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> After merging the final tree, today's linux-next build (powerpc
> ppc44x_defconfig) produced tis warning:
>
> WARNING: net/sunrpc/sunrpc.o(.init.text+0x110): Section mismatch in reference from the function init_sunrpc() to the function .exit.text:rpcauth_remove_module()
> The function __init init_sunrpc() references
> a function __exit rpcauth_remove_module().
> This is often seen when error handling in the init function
> uses functionality in the exit path.
> The fix is often to remove the __exit annotation of
> rpcauth_remove_module() so it may be used outside an exit section.
>
> Probably caused by commit 2f72c9b737
> ("sunrpc: The per-net skeleton").
This actually causes a build failure on a sparc32 defconfig build:
`rpcauth_remove_module' referenced in section `.init.text' of net/built-in.o: defined in discarded section `.exit.text' of net/built-in.o
I applied the following patch for today:
Fixes:
`rpcauth_remove_module' referenced in section `.init.text' of net/built-in.o: defined in discarded section `.exit.text' of net/built-in.o
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The maximum size of the authcache is now set to 1024 (10 bits),
but on our server we need at least 4096 (12 bits). Increase
MAX_HASHTABLE_BITS to 14. This is a maximum of 16384 entries,
each containing a pointer (8 bytes on x86_64). This is
exactly the limit of kmalloc() (128K).
Signed-off-by: Miquel van Smoorenburg <mikevs@xs4all.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
After merging the rr tree, today's linux-next build (powerpc
ppc64_defconfig) failed like this:
net/sunrpc/auth.c:74: error: 'param_ops_hashtbl_sz' undeclared here (not in a function)
Caused by commit 0685652df0929cec7d78efa85127f6eb34962132
("param:param_ops") interacting with commit
f8f853ab19fcc415b6eadd273373edc424916212 ("SUNRPC: Make the credential
cache hashtable size configurable") from the nfs tree.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* 'nfs-for-2.6.36' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (42 commits)
NFS: NFSv4.1 is no longer a "developer only" feature
NFS: NFS_V4 is no longer an EXPERIMENTAL feature
NFS: Fix /proc/mount for legacy binary interface
NFS: Fix the locking in nfs4_callback_getattr
SUNRPC: Defer deleting the security context until gss_do_free_ctx()
SUNRPC: prevent task_cleanup running on freed xprt
SUNRPC: Reduce asynchronous RPC task stack usage
SUNRPC: Move the bound cred to struct rpc_rqst
SUNRPC: Clean up of rpc_bindcred()
SUNRPC: Move remaining RPC client related task initialisation into clnt.c
SUNRPC: Ensure that rpc_exit() always wakes up a sleeping task
SUNRPC: Make the credential cache hashtable size configurable
SUNRPC: Store the hashtable size in struct rpc_cred_cache
NFS: Ensure the AUTH_UNIX credcache is allocated dynamically
NFS: Fix the NFS users of rpc_restart_call()
SUNRPC: The function rpc_restart_call() should return success/failure
NFSv4: Get rid of the bogus RPC_ASSASSINATED(task) checks
NFSv4: Clean up the process of renewing the NFSv4 lease
NFSv4.1: Handle NFS4ERR_DELAY on SEQUENCE correctly
NFS: nfs_rename() should not have to flush out writebacks
...
This will allow us to save the original generic cred in rpc_message, so
that if we migrate from one server to another, we can generate a new bound
cred without having to punt back to the NFS layer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch allows the user to configure the credential cache hashtable size
using a new module parameter: auth_hashtable_size
When set, this parameter will be rounded up to the nearest power of two,
with a maximum allowed value of 1024 elements.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add the shrinkers missed in the first conversion of the API in
commit 7f8275d0d6 ("mm: add context argument to
shrinker callback").
Signed-off-by: Dave Chinner <dchinner@redhat.com>
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>
NeilBrown
Trond Myklebust
Daniel Walter
Jeff Layton
Andy Adamson
Peter Zijlstra
Dave Chinner
Trond Myklebust
Chuck Lever
Sasha Levin
Eric W. Biederman
Joe Perches
Ying Han
Linus Torvalds
Stephen Rothwell
Miquel van Smoorenburg
Peter Staubach
David Howells