If rpc.gssd sends us an acceptor name string trailing the context token,
stash it as part of the context.
Signed-off-by: NJeff Layton <jlayton@poochiereds.net>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Mostly scripted conversion of the smp_mb__* barriers.
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

In gss_alloc_msg(), if the call to gss_encode_v1_msg() fails, we
want to release the reference to the pipe_version that was obtained
earlier in the function.

Fixes: 9d3a2260 (SUNRPC: Fix buffer overflow checking in...)
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Fix a race in which the RPC client is shutting down while the
gss daemon is processing a downcall. If the RPC client manages to
shut down before the gss daemon is done, then the struct gss_auth
used in gss_release_msg() may have already been freed.

Link: http://lkml.kernel.org/r/1392494917.71728.YahooMailNeo@web140002.mail.bf1.yahoo.comReported-by: NJohn <da_audiophile@yahoo.com>
Reported-by: NBorislav Petkov <bp@alien8.de>
Cc: stable@vger.kernel.org # 3.12+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

An infinite loop is caused when nfs4_establish_lease() fails
with -EACCES. This causes nfs4_handle_reclaim_lease_error()
to sleep a bit and resets the NFS4CLNT_LEASE_EXPIRED bit.
This in turn causes nfs4_state_manager() to try and
reestablished the lease, again, again, again...

The problem is a valid RPCSEC_GSS client is being created when
rpc.gssd is not running.

Link: http://lkml.kernel.org/r/1392066375-16502-1-git-send-email-steved@redhat.com
Fixes: 0ea9de0e (sunrpc: turn warn_gssd() log message into a dprintk())
Reported-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The original printk() made sense when the GSSAPI codepaths were called
only when sec=krb5* was explicitly requested. Now however, in many cases
the nfs client will try to acquire GSSAPI credentials by default, even
when it's not requested.

Since we don't have a great mechanism to distinguish between the two
cases, just turn the pr_warn into a dprintk instead. With this change we
can also get rid of the ratelimiting.

We do need to keep the EXPORT_SYMBOL(gssd_running) in place since
auth_gss.ko needs it and sunrpc.ko provides it. We can however,
eliminate the gssd_running call in the nfs code since that's a bit of a
layering violation.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Now that we have a more reliable method to tell if gssd is running, we
can replace the sn->gssd_running flag with a function that will query to
see if it's up and running.

There's also no need to attempt an upcall that we know will fail, so
just return -EACCES if gssd isn't running. Finally, fix the warn_gss()
message not to claim that that the upcall timed out since we don't
necesarily perform one now when gssd isn't running, and remove the
extraneous newline from the message.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Otherwise RPCSEC_GSS_DESTROY messages are not sent.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In gss_encode_v1_msg, it is pointless to BUG() after the overflow has
happened. Replace the existing sprintf()-based code with scnprintf(),
and warn if an overflow is ever triggered.

In gss_encode_v0_msg, replace the runtime BUG_ON() with an appropriate
compile-time BUILD_BUG_ON.
Reported-by: NBruce Fields <bfields@fieldses.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add the missing 'break' to ensure that we don't corrupt a legacy 'v0' type
message by appending the 'v1'.

Cc: Bruce Fields <bfields@fieldses.org>
Cc: stable@vger.kernel.org
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This fixes a regression since  eb6dc19d
"RPCSEC_GSS: Share all credential caches on a per-transport basis" which
could cause an occasional oops in the nfsd code (see below).

The problem was that an auth was left referencing a client that had been
freed.  To avoid this we need to ensure that auths are shared only
between descendants of a common client; the fact that a clone of an
rpc_client takes a reference on its parent then ensures that the parent
client will last as long as the auth.

Also add a comment explaining what I think was the intention of this
code.

  general protection fault: 0000 [#1] PREEMPT SMP
  Modules linked in: rpcsec_gss_krb5 nfsd auth_rpcgss oid_registry nfs_acl lockd sunrpc
  CPU: 3 PID: 4071 Comm: kworker/u8:2 Not tainted 3.11.0-rc2-00182-g025145f #1665
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  Workqueue: nfsd4_callbacks nfsd4_do_callback_rpc [nfsd]
  task: ffff88003e206080 ti: ffff88003c384000 task.ti: ffff88003c384000
  RIP: 0010:[<ffffffffa00001f3>]  [<ffffffffa00001f3>] rpc_net_ns+0x53/0x70 [sunrpc]
  RSP: 0000:ffff88003c385ab8  EFLAGS: 00010246
  RAX: 6b6b6b6b6b6b6b6b RBX: ffff88003af9a800 RCX: 0000000000000002
  RDX: ffffffffa00001a5 RSI: 0000000000000001 RDI: ffffffff81e284e0
  RBP: ffff88003c385ad8 R08: 0000000000000001 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000015 R12: ffff88003c990840
  R13: ffff88003c990878 R14: ffff88003c385ba8 R15: ffff88003e206080
  FS:  0000000000000000(0000) GS:ffff88003fd80000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 00007fcdf737e000 CR3: 000000003ad2b000 CR4: 00000000000006e0
  Stack:
   ffffffffa00001a5 0000000000000006 0000000000000006 ffff88003af9a800
   ffff88003c385b08 ffffffffa00d52a4 ffff88003c385ba8 ffff88003c751bd8
   ffff88003c751bc0 ffff88003e113600 ffff88003c385b18 ffffffffa00d530c
  Call Trace:
   [<ffffffffa00001a5>] ? rpc_net_ns+0x5/0x70 [sunrpc]
   [<ffffffffa00d52a4>] __gss_pipe_release+0x54/0x90 [auth_rpcgss]
   [<ffffffffa00d530c>] gss_pipe_free+0x2c/0x30 [auth_rpcgss]
   [<ffffffffa00d678b>] gss_destroy+0x9b/0xf0 [auth_rpcgss]
   [<ffffffffa000de63>] rpcauth_release+0x23/0x30 [sunrpc]
   [<ffffffffa0001e81>] rpc_release_client+0x51/0xb0 [sunrpc]
   [<ffffffffa00020d5>] rpc_shutdown_client+0xe5/0x170 [sunrpc]
   [<ffffffff81098a14>] ? cpuacct_charge+0xa4/0xb0
   [<ffffffff81098975>] ? cpuacct_charge+0x5/0xb0
   [<ffffffffa019556f>] nfsd4_process_cb_update.isra.17+0x2f/0x210 [nfsd]
   [<ffffffff819a4ac0>] ? _raw_spin_unlock_irq+0x30/0x60
   [<ffffffff819a4acb>] ? _raw_spin_unlock_irq+0x3b/0x60
   [<ffffffff810703ab>] ? process_one_work+0x15b/0x510
   [<ffffffffa01957dd>] nfsd4_do_callback_rpc+0x8d/0xa0 [nfsd]
   [<ffffffff8107041e>] process_one_work+0x1ce/0x510
   [<ffffffff810703ab>] ? process_one_work+0x15b/0x510
   [<ffffffff810712ab>] worker_thread+0x11b/0x370
   [<ffffffff81071190>] ? manage_workers.isra.24+0x2b0/0x2b0
   [<ffffffff8107854b>] kthread+0xdb/0xe0
   [<ffffffff819a4ac0>] ? _raw_spin_unlock_irq+0x30/0x60
   [<ffffffff81078470>] ? __init_kthread_worker+0x70/0x70
   [<ffffffff819ac7dc>] ret_from_fork+0x7c/0xb0
   [<ffffffff81078470>] ? __init_kthread_worker+0x70/0x70
  Code: a5 01 00 a0 31 d2 31 f6 48 c7 c7 e0 84 e2 81 e8 f4 91 0a e1 48 8b 43 60 48 c7 c2 a5 01 00 a0 be 01 00 00 00 48 c7 c7 e0 84 e2 81 <48> 8b 98 10 07 00 00 e8 91 8f 0a e1 e8
  +3c 4e 07 e1 48 83 c4 18
  RIP  [<ffffffffa00001f3>] rpc_net_ns+0x53/0x70 [sunrpc]
   RSP <ffff88003c385ab8>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Fix the declaration of the gss_auth_hash_table so that it creates
a 16 bucket hashtable, as I had intended.
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Most of the time an error from the credops crvalidate function means the
server has sent us a garbage verifier. The gss_validate function is the
exception where there is an -EACCES case if the user GSS_context on the client
has expired.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ensure that all struct rpc_clnt for any given socket/rdma channel
share the same RPCSEC_GSS/krb5,krb5i,krb5p caches.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ensure that if an rpc_clnt owns more than one RPCSEC_GSS-based authentication
mechanism, then those caches will share the same 'gssd' upcall pipe.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If an error condition occurs on rpc_pipefs creation, or the user mounts
rpc_pipefs and then unmounts it, then the dentries in struct gss_auth
need to be reset to NULL so that a second call to gss_pipes_dentries_destroy
doesn't try to free them again.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Don't pass the rpc_client as a parameter, when what we really want is
the net namespace.
Signed-off-by: NTrond 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: NTrond Myklebust <Trond.Myklebust@netapp.com>

Optimise away gss_encode_msg: we don't need to look up the pipe
version a second time.

Save the gss target name in struct gss_auth. It is a property of the
auth cache itself, and doesn't really belong in the rpc_client.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This seems to have been overlooked when we did the namespace
conversion. If a container is running a legacy version of rpc.gssd
then it will be disrupted if the global 'pipe_version' is set by a
container running the new version of rpc.gssd.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Recent changes to the NFS security flavour negotiation mean that
we have a stronger dependency on rpc.gssd. If the latter is not
running, because the user failed to start it, then we time out
and mark the container as not having an instance. We then
use that information to time out faster the next time.

If, on the other hand, the rpc.gssd successfully binds to an rpc_pipe,
then we mark the container as having an rpc.gssd instance.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If wait_event_interruptible_timeout() is successful, it returns
the number of seconds remaining until the timeout. In that
case, we should be retrying the upcall.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Just convert those messages to dprintk()s so that they can be used
when debugging.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We expose this parameter for a future caller.
It will be used to extract the endtime from the gss-proxy upcall mechanism,
in order to set the rsc cache expiration time.
Signed-off-by: NSimo Sorce <simo@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.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: NChuck Lever <chuck.lever@oracle.com>
Acked-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NTrond 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: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Commit f344f6df "SUNRPC: Auto-load RPC authentication kernel
modules", Mon Mar 20 13:44:08 2006, adds a request_module() call
in rpcauth_create() to auto-load RPC security modules when a ULP
tries to create a credential of that flavor.

In rpcauth_create(), the name of the module to load is built like
this:

	request_module("rpc-auth-%u", flavor);

This means that for, say, RPC_AUTH_GSS, request_module() is looking
for a module or alias called "rpc-auth-6".

The GSS module is named "auth_rpcgss", and commit f344f6df does not
add any new module aliases.  There is also no such alias provided in
/etc/modprobe.d on my system (Fedora 16).  Without this alias, the
GSS module is not loaded on demand.

This is used by rpcauth_create().  The pseudoflavor_to_flavor() call
can return RPC_AUTH_GSS, which is passed to request_module().
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Since commit 620038f6, gcc is throwing the following warning:

  CC [M]  net/sunrpc/auth_gss/auth_gss.o
In file included from include/linux/sunrpc/types.h:14:0,
                 from include/linux/sunrpc/sched.h:14,
                 from include/linux/sunrpc/clnt.h:18,
                 from net/sunrpc/auth_gss/auth_gss.c:45:
net/sunrpc/auth_gss/auth_gss.c: In function ‘gss_pipe_downcall’:
include/linux/sunrpc/debug.h:45:10: warning: ‘timeout’ may be used
uninitialized in this function [-Wmaybe-uninitialized]
    printk(KERN_DEFAULT args); \
          ^
net/sunrpc/auth_gss/auth_gss.c:194:15: note: ‘timeout’ was declared here
  unsigned int timeout;
               ^
If simple_get_bytes returns an error, then we'll end up calling printk
with an uninitialized timeout value. Reasonably harmless, but fairly
simple to fix by removing the printout of the uninitialised parameters.

Cc: Andy Adamson <andros@netapp.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
[Trond: just remove the parameters rather than initialising timeout]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

- Use from_kuid when generating the on the wire uid values.
- Use make_kuid when reading on the wire values.

In gss_encode_v0_msg, since the uid in gss_upcall_msg is now a kuid_t
generate the necessary uid_t value on the stack copy it into
gss_msg->databuf where it can safely live until the message is no
longer needed.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

When printing kuids and kgids for debugging purpropses convert them
to ordinary integers so their values can be fed to the oridnary
print functions.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

When comparing uids use uid_eq instead of ==.
When comparing gids use gid_eq instead of ==.

And unfortunate cost of type safety.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Convert variables that store uids and gids to be of type
kuid_t and kgid_t instead of type uid_t and gid_t.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

tk_xprt is just a shortcut for tk_client->cl_xprt, however cl_xprt is
defined as an __rcu variable. Replace dereferences of tk_xprt with
non-rcu dereferences where it is safe to do so.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Only use the default GSSD_MIN_TIMEOUT if the gss downcall timeout is zero.
Store the full lifetime in gc_expiry (not 3/4 of the lifetime) as subsequent
patches will use the gc_expiry to determine buffered WRITE behavior in the
face of expired or soon to be expired gss credentials.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: Some function names have changed, but debugging messages
were never updated.  Automate the construction of the function name
in debugging messages.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.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: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

A migration event will replace the rpc_xprt used by an rpc_clnt.  To
ensure this can be done safely, all references to cl_xprt must now use
a form of rcu_dereference().

Special care is taken with rpc_peeraddr2str(), which returns a pointer
to memory whose lifetime is the same as the rpc_xprt.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
[ cel: fix lockdep splats and layering violations ]
[ cel: forward ported to 3.4 ]
[ cel: remove rpc_max_reqs(), add rpc_net_ns() ]
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>