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: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond 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: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The patch "SUNRPC: Add rpcauth_list_flavors()" introduces a new error
path in gss_mech_list_pseudoflavors, but fails to release the spin lock.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Trond 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: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Pull the rest of the nfsd commits from Bruce Fields:
 "... and then I cherry-picked the remainder of the patches from the
  head of my previous branch"

This is the rest of the original nfsd branch, rebased without the
delegation stuff that I thought really needed to be redone.

I don't like rebasing things like this in general, but in this situation
this was the lesser of two evils.

* 'for-3.5' of git://linux-nfs.org/~bfields/linux: (50 commits)
  nfsd4: fix, consolidate client_has_state
  nfsd4: don't remove rebooted client record until confirmation
  nfsd4: remove some dprintk's and a comment
  nfsd4: return "real" sequence id in confirmed case
  nfsd4: fix exchange_id to return confirm flag
  nfsd4: clarify that renewing expired client is a bug
  nfsd4: simpler ordering of setclientid_confirm checks
  nfsd4: setclientid: remove pointless assignment
  nfsd4: fix error return in non-matching-creds case
  nfsd4: fix setclientid_confirm same_cred check
  nfsd4: merge 3 setclientid cases to 2
  nfsd4: pull out common code from setclientid cases
  nfsd4: merge last two setclientid cases
  nfsd4: setclientid/confirm comment cleanup
  nfsd4: setclientid remove unnecessary terms from a logical expression
  nfsd4: move rq_flavor into svc_cred
  nfsd4: stricter cred comparison for setclientid/exchange_id
  nfsd4: move principal name into svc_cred
  nfsd4: allow removing clients not holding state
  nfsd4: rearrange exchange_id logic to simplify
  ...

Pull nfsd update from Bruce Fields.

* 'for-3.5-take-2' of git://linux-nfs.org/~bfields/linux: (23 commits)
  nfsd: trivial: use SEEK_SET instead of 0 in vfs_llseek
  SUNRPC: split upcall function to extract reusable parts
  nfsd: allocate id-to-name and name-to-id caches in per-net operations.
  nfsd: make name-to-id cache allocated per network namespace context
  nfsd: make id-to-name cache allocated per network namespace context
  nfsd: pass network context to idmap init/exit functions
  nfsd: allocate export and expkey caches in per-net operations.
  nfsd: make expkey cache allocated per network namespace context
  nfsd: make export cache allocated per network namespace context
  nfsd: pass pointer to export cache down to stack wherever possible.
  nfsd: pass network context to export caches init/shutdown routines
  Lockd: pass network namespace to creation and destruction routines
  NFSd: remove hard-coded dereferences to name-to-id and id-to-name caches
  nfsd: pass pointer to expkey cache down to stack wherever possible.
  nfsd: use hash table from cache detail in nfsd export seq ops
  nfsd: pass svc_export_cache pointer as private data to "exports" seq file ops
  nfsd: use exp_put() for svc_export_cache put
  nfsd: use cache detail pointer from svc_export structure on cache put
  nfsd: add link to owner cache detail to svc_export structure
  nfsd: use passed cache_detail pointer expkey_parse()
  ...

Move the rq_flavor into struct svc_cred, and use it in setclientid and
exchange_id comparisons as well.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Instead of keeping the principal name associated with a request in a
structure that's private to auth_gss and using an accessor function,
move it to svc_cred.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The data in Kerberos gss tokens can be rotated.  But we were lazy and
rejected any nonzero rotation value.  It wasn't necessary for the
implementations we were testing against at the time.

But it appears that Windows does use a nonzero value here.

So, implement rotation to bring ourselves into compliance with the spec
and to interoperate with Windows.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Pull user namespace enhancements from Eric Biederman:
 "This is a course correction for the user namespace, so that we can
  reach an inexpensive, maintainable, and reasonably complete
  implementation.

  Highlights:
   - Config guards make it impossible to enable the user namespace and
     code that has not been converted to be user namespace safe.

   - Use of the new kuid_t type ensures the if you somehow get past the
     config guards the kernel will encounter type errors if you enable
     user namespaces and attempt to compile in code whose permission
     checks have not been updated to be user namespace safe.

   - All uids from child user namespaces are mapped into the initial
     user namespace before they are processed.  Removing the need to add
     an additional check to see if the user namespace of the compared
     uids remains the same.

   - With the user namespaces compiled out the performance is as good or
     better than it is today.

   - For most operations absolutely nothing changes performance or
     operationally with the user namespace enabled.

   - The worst case performance I could come up with was timing 1
     billion cache cold stat operations with the user namespace code
     enabled.  This went from 156s to 164s on my laptop (or 156ns to
     164ns per stat operation).

   - (uid_t)-1 and (gid_t)-1 are reserved as an internal error value.
     Most uid/gid setting system calls treat these value specially
     anyway so attempting to use -1 as a uid would likely cause
     entertaining failures in userspace.

   - If setuid is called with a uid that can not be mapped setuid fails.
     I have looked at sendmail, login, ssh and every other program I
     could think of that would call setuid and they all check for and
     handle the case where setuid fails.

   - If stat or a similar system call is called from a context in which
     we can not map a uid we lie and return overflowuid.  The LFS
     experience suggests not lying and returning an error code might be
     better, but the historical precedent with uids is different and I
     can not think of anything that would break by lying about a uid we
     can't map.

   - Capabilities are localized to the current user namespace making it
     safe to give the initial user in a user namespace all capabilities.

  My git tree covers all of the modifications needed to convert the core
  kernel and enough changes to make a system bootable to runlevel 1."

Fix up trivial conflicts due to nearby independent changes in fs/stat.c

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits)
  userns:  Silence silly gcc warning.
  cred: use correct cred accessor with regards to rcu read lock
  userns: Convert the move_pages, and migrate_pages permission checks to use uid_eq
  userns: Convert cgroup permission checks to use uid_eq
  userns: Convert tmpfs to use kuid and kgid where appropriate
  userns: Convert sysfs to use kgid/kuid where appropriate
  userns: Convert sysctl permission checks to use kuid and kgids.
  userns: Convert proc to use kuid/kgid where appropriate
  userns: Convert ext4 to user kuid/kgid where appropriate
  userns: Convert ext3 to use kuid/kgid where appropriate
  userns: Convert ext2 to use kuid/kgid where appropriate.
  userns: Convert devpts to use kuid/kgid where appropriate
  userns: Convert binary formats to use kuid/kgid where appropriate
  userns: Add negative depends on entries to avoid building code that is userns unsafe
  userns: signal remove unnecessary map_cred_ns
  userns: Teach inode_capable to understand inodes whose uids map to other namespaces.
  userns: Fail exec for suid and sgid binaries with ids outside our user namespace.
  userns: Convert stat to return values mapped from kuids and kgids
  userns: Convert user specfied uids and gids in chown into kuids and kgid
  userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs
  ...