linux.git/fs/nfsd, branch v5.5

Merge tag 'nfsd-5.5' of git://linux-nfs.org/~bfields/linux

2019-12-08T00:56:00+00:00

Pull nfsd updates from Bruce Fields:
 "This is a relatively quiet cycle for nfsd, mainly various bugfixes.

  Possibly most interesting is Trond's fixes for some callback races
  that were due to my incomplete understanding of rpc client shutdown.
  Unfortunately at the last minute I've started noticing a new
  intermittent failure to send callbacks. As the logic seems basically
  correct, I'm leaving Trond's patches in for now, and hope to find a
  fix in the next week so I don't have to revert those patches"

* tag 'nfsd-5.5' of git://linux-nfs.org/~bfields/linux: (24 commits)
  nfsd: depend on CRYPTO_MD5 for legacy client tracking
  NFSD fixing possible null pointer derefering in copy offload
  nfsd: check for EBUSY from vfs_rmdir/vfs_unink.
  nfsd: Ensure CLONE persists data and metadata changes to the target file
  SUNRPC: Fix backchannel latency metrics
  nfsd: restore NFSv3 ACL support
  nfsd: v4 support requires CRYPTO_SHA256
  nfsd: Fix cld_net->cn_tfm initialization
  lockd: remove __KERNEL__ ifdefs
  sunrpc: remove __KERNEL__ ifdefs
  race in exportfs_decode_fh()
  nfsd: Drop LIST_HEAD where the variable it declares is never used.
  nfsd: document callback_wq serialization of callback code
  nfsd: mark cb path down on unknown errors
  nfsd: Fix races between nfsd4_cb_release() and nfsd4_shutdown_callback()
  nfsd: minor 4.1 callback cleanup
  SUNRPC: Fix svcauth_gss_proxy_init()
  SUNRPC: Trace gssproxy upcall results
  sunrpc: fix crash when cache_head become valid before update
  nfsd: remove private bin2hex implementation
  ...

nfsd: depend on CRYPTO_MD5 for legacy client tracking

2019-12-07T16:28:52+00:00

The legacy client tracking infrastructure of nfsd makes use of MD5 to
derive a client's recovery directory name. As the nfsd module doesn't
declare any dependency on CRYPTO_MD5, though, it may fail to allocate
the hash if the kernel was compiled without it. As a result, generation
of client recovery directories will fail with the following error:

    NFSD: unable to generate recoverydir name

The explicit dependency on CRYPTO_MD5 was removed as redundant back in
6aaa67b5f3b9 (NFSD: Remove redundant "select" clauses in fs/Kconfig
2008-02-11) as it was already implicitly selected via RPCSEC_GSS_KRB5.
This broke when RPCSEC_GSS_KRB5 was made optional for NFSv4 in commit
df486a25900f (NFS: Fix the selection of security flavours in Kconfig) at
a later point.

Fix the issue by adding back an explicit dependency on CRYPTO_MD5.

Fixes: df486a25900f (NFS: Fix the selection of security flavours in Kconfig)
Signed-off-by: Patrick Steinhardt 
Signed-off-by: J. Bruce Fields

NFSD fixing possible null pointer derefering in copy offload

2019-12-07T16:28:46+00:00

Static checker revealed possible error path leading to possible
NULL pointer dereferencing.

Reported-by: Dan Carpenter 
Fixes: e0639dc5805a: ("NFSD introduce async copy feature")
Signed-off-by: Olga Kornievskaia 
Signed-off-by: J. Bruce Fields

nfsd: check for EBUSY from vfs_rmdir/vfs_unink.

2019-11-30T19:59:52+00:00

vfs_rmdir and vfs_unlink can return -EBUSY if the
target is a mountpoint.  This currently gets passed to
nfserrno() by nfsd_unlink(), and that results in a WARNing,
which is not user-friendly.

Possibly the best NFSv4 error is NFS4ERR_FILE_OPEN, because
there is a sense in which the object is currently in use
by some other task.  The Linux NFSv4 client will map this
back to EBUSY, which is an added benefit.

For NFSv3, the best we can do is probably NFS3ERR_ACCES, which isn't
true, but is not less true than the other options.

Signed-off-by: NeilBrown 
Signed-off-by: J. Bruce Fields

nfsd: Ensure CLONE persists data and metadata changes to the target file

2019-11-30T19:55:38+00:00

The NFSv4.2 CLONE operation has implicit persistence requirements on the
target file, since there is no protocol requirement that the client issue
a separate operation to persist data.
For that reason, we should call vfs_fsync_range() on the destination file
after a successful call to vfs_clone_file_range().

Fixes: ffa0160a1039 ("nfsd: implement the NFSv4.2 CLONE operation")
Signed-off-by: Trond Myklebust 
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: J. Bruce Fields

nfsd: restore NFSv3 ACL support

2019-11-19T22:43:05+00:00

An error in e333f3bbefe3 left the nfsd_acl_program->pg_vers array empty,
which effectively turned off the server's support for NFSv3 ACLs.

Fixes: e333f3bbefe3 "nfsd: Allow containers to set supported nfs versions"
Cc: stable@vger.kernel.org
Cc: Trond Myklebust 
Signed-off-by: J. Bruce Fields

new helper: lookup_positive_unlocked()

2019-11-15T18:49:04+00:00

Most of the callers of lookup_one_len_unlocked() treat negatives are
ERR_PTR(-ENOENT).  Provide a helper that would do just that.  Note
that a pinned positive dentry remains positive - it's ->d_inode is
stable, etc.; a pinned _negative_ dentry can become positive at any
point as long as you are not holding its parent at least shared.
So using lookup_one_len_unlocked() needs to be careful;
lookup_positive_unlocked() is safer and that's what the callers
end up open-coding anyway.

Signed-off-by: Al Viro

nfsd: v4 support requires CRYPTO_SHA256

2019-11-12T19:53:26+00:00

The new nfsdcld client tracking operations use sha256 to compute hashes
of the kerberos principals, so make sure CRYPTO_SHA256 is enabled.

Fixes: 6ee95d1c8991 ("nfsd: add support for upcall version 2")
Reported-by: Jamie Heilman 
Signed-off-by: Scott Mayhew 
Signed-off-by: J. Bruce Fields

nfsd: Fix cld_net->cn_tfm initialization

2019-11-12T19:53:26+00:00

Don't assign an error pointer to cld_net->cn_tfm, otherwise an oops will
occur in nfsd4_remove_cld_pipe().

Also, move the initialization of cld_net->cn_tfm so that it occurs after
the check to see if nfsdcld is running.  This is necessary because
nfsd4_client_tracking_init() looks for -ETIMEDOUT to determine whether
to use the "old" nfsdcld tracking ops.

Fixes: 6ee95d1c8991 ("nfsd: add support for upcall version 2")
Reported-by: Jamie Heilman 
Signed-off-by: Scott Mayhew 
Signed-off-by: J. Bruce Fields

nfsd: Drop LIST_HEAD where the variable it declares is never used.

2019-11-08T17:32:59+00:00

The declarations were introduced with the file, but the declared
variables were not used.

Fixes: 65294c1f2c5e ("nfsd: add a new struct file caching facility to nfsd")
Signed-off-by: Mao Wenan 
Signed-off-by: J. Bruce Fields