linux-stable.git/fs/lockd, branch v4.9.321

lockd: don't use interval-based rebinding over TCP

2020-12-29T12:44:57+00:00

[ Upstream commit 9b82d88d5976e5f2b8015d58913654856576ace5 ]

NLM uses an interval-based rebinding, i.e. it clears the transport's
binding under certain conditions if more than 60 seconds have elapsed
since the connection was last bound.

This rebinding is not necessary for an autobind RPC client over a
connection-oriented protocol like TCP.

It can also cause problems: it is possible for nlm_bind_host() to clear
XPRT_BOUND whilst a connection worker is in the middle of trying to
reconnect, after it had already been checked in xprt_connect().

When the connection worker notices that XPRT_BOUND has been cleared
under it, in xs_tcp_finish_connecting(), that results in:

	xs_tcp_setup_socket: connect returned unhandled error -107

Worse, it's possible that the two can get into lockstep, resulting in
the same behaviour repeated indefinitely, with the above error every
300 seconds, without ever recovering, and the connection never being
established. This has been seen in practice, with a large number of NLM
client tasks, following a server restart.

The existing callers of nlm_bind_host & nlm_rebind_host should not need
to force the rebind, for TCP, so restrict the interval-based rebinding
to UDP only.

For TCP, we will still rebind when needed, e.g. on timeout, and connection
error (including closure), since connection-related errors on an existing
connection, ECONNREFUSED when trying to connect, and rpc_check_timeout(),
already unconditionally clear XPRT_BOUND.

To avoid having to add the fix, and explanation, to both nlm_bind_host()
and nlm_rebind_host(), remove the duplicate code from the former, and
have it call the latter.

Drop the dprintk, which adds no value over a trace.

Signed-off-by: Calum Mackay 
Fixes: 35f5a422ce1a ("SUNRPC: new interface to force an RPC rebind")
Signed-off-by: Trond Myklebust 
Signed-off-by: Sasha Levin

lockd: fix access beyond unterminated strings in prints

2018-11-13T19:17:02+00:00

commit 93f38b6fae0ea8987e22d9e6c38f8dfdccd867ee upstream.

printk format used %*s instead of %.*s, so hostname_len does not limit
the number of bytes accessed from hostname.

Signed-off-by: Amir Goldstein 
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

lockd: lost rollback of set_grace_period() in lockd_down_net()

2018-05-19T08:27:00+00:00

commit 3a2b19d1ee5633f76ae8a88da7bc039a5d1732aa upstream.

Commit efda760fe95ea ("lockd: fix lockd shutdown race") is incorrect,
it removes lockd_manager and disarm grace_period_end for init_net only.

If nfsd was started from another net namespace lockd_up_net() calls
set_grace_period() that adds lockd_manager into per-netns list
and queues grace_period_end delayed work.

These action should be reverted in lockd_down_net().
Otherwise it can lead to double list_add on after restart nfsd in netns,
and to use-after-free if non-disarmed delayed work will be executed after netns destroy.

Fixes: efda760fe95e ("lockd: fix lockd shutdown race")
Cc: stable@vger.kernel.org
Signed-off-by: Vasily Averin 
Signed-off-by: J. Bruce Fields 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

lockd: fix lockd shutdown race

2018-04-13T17:47:53+00:00

[ Upstream commit efda760fe95ea15291853c8fa9235c32d319cd98 ]

As reported by David Jeffery: "a signal was sent to lockd while lockd
was shutting down from a request to stop nfs.  The signal causes lockd
to call restart_grace() which puts the lockd_net structure on the grace
list.  If this signal is received at the wrong time, it will occur after
lockd_down_net() has called locks_end_grace() but before
lockd_down_net() stops the lockd thread.  This leads to lockd putting
the lockd_net structure back on the grace list, then exiting without
anything removing it from the list."

So, perform the final locks_end_grace() from the the lockd thread; this
ensures it's serialized with respect to restart_grace().

Reported-by: David Jeffery 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

lockd: double unregister of inetaddr notifiers

2017-11-30T08:39:06+00:00

commit dc3033e16c59a2c4e62b31341258a5786cbcee56 upstream.

lockd_up() can call lockd_unregister_notifiers twice:
inside lockd_start_svc() when it calls lockd_svc_exit_thread()
and then in error path of lockd_up()

Patch forces lockd_start_svc() to unregister notifiers in all error cases
and removes extra unregister in error path of lockd_up().

Fixes: cb7d224f82e4 "lockd: unregister notifier blocks if the service ..."
Signed-off-by: Vasily Averin 
Reviewed-by: Jeff Layton 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

treewide: remove redundant #include

2016-10-11T22:06:33+00:00

Kernel source files need not include  explicitly
because the top Makefile forces to include it with:

  -include $(srctree)/include/linux/kconfig.h

This commit removes explicit includes except the following:

  * arch/s390/include/asm/facilities_src.h
  * tools/testing/radix-tree/linux/kernel.h

These two are used for host programs.

Link: http://lkml.kernel.org/r/1473656164-11929-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-07-28T19:59:05+00:00

Pull vfs updates from Al Viro:
 "Assorted cleanups and fixes.

  Probably the most interesting part long-term is ->d_init() - that will
  have a bunch of followups in (at least) ceph and lustre, but we'll
  need to sort the barrier-related rules before it can get used for
  really non-trivial stuff.

  Another fun thing is the merge of ->d_iput() callers (dentry_iput()
  and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all
  except the one in __d_lookup_lru())"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  fs/dcache.c: avoid soft-lockup in dput()
  vfs: new d_init method
  vfs: Update lookup_dcache() comment
  bdev: get rid of ->bd_inodes
  Remove last traces of ->sync_page
  new helper: d_same_name()
  dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends()
  vfs: clean up documentation
  vfs: document ->d_real()
  vfs: merge .d_select_inode() into .d_real()
  unify dentry_iput() and dentry_unlink_inode()
  binfmt_misc: ->s_root is not going anywhere
  drop redundant ->owner initializations
  ufs: get rid of redundant checks
  orangefs: constify inode_operations
  missed comment updates from ->direct_IO() prototype change
  file_inode(f)->i_mapping is f->f_mapping
  trim fsnotify hooks a bit
  9p: new helper - v9fs_parent_fid()
  debugfs: ->d_parent is never NULL or negative
  ...

lockd: unregister notifier blocks if the service fails to come up completely

2016-06-30T20:35:07+00:00

If the lockd service fails to start up then we need to be sure that the
notifier blocks are not registered, otherwise a subsequent start of the
service could cause the same notifier to be registered twice, leading to
soft lockups.

Signed-off-by: Scott Mayhew 
Cc: stable@vger.kernel.org
Fixes: 0751ddf77b6a "lockd: Register callbacks on the inetaddr_chain..."
Signed-off-by: J. Bruce Fields

drop redundant ->owner initializations

2016-05-29T23:08:00+00:00

it's not needed for file_operations of inodes located on fs defined
in the hosting module and for file_operations that go into procfs.

Signed-off-by: Al Viro

lockd: constify nlmsvc_binding structure

2016-01-07T15:10:50+00:00

The nlmsvc_binding structure is never modified, so declare it as const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall 
Signed-off-by: J. Bruce Fields