Skip to content

K
Kernel

openeuler / Kernel
1 年多 前同步成功

通知 8
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 24 12月, 2008 3 次提交
    • C
      NFS: add "[no]resvport" mount option · d740351b
      由 Chuck Lever 提交于 
      The standard default security setting for NFS is AUTH_SYS.  An NFS
client connects to NFS servers via a privileged source port and a
fixed standard destination port (2049).  The client sends raw uid and
gid numbers to identify users making NFS requests, and the server
assumes an appropriate authority on the client has vetted these
values because the source port is privileged.

On Linux, by default in-kernel RPC services use a privileged port in
the range between 650 and 1023 to avoid using source ports of well-
known IP services.  Using such a small range limits the number of NFS
mount points and the number of unique NFS servers to which a client
can connect concurrently.

An NFS client can use unprivileged source ports to expand the range of
source port numbers, allowing more concurrent server connections and
more NFS mount points.  Servers must explicitly allow NFS connections
from unprivileged ports for this to work.

In the past, bumping the value of the sunrpc.max_resvport sysctl on
the client would permit the NFS client to use unprivileged ports.
Bumping this setting also changes the maximum port number used by
other in-kernel RPC services, some of which still required a port
number less than 1023.

This is exacerbated by the way source port numbers are chosen by the
Linux RPC client, which starts at the top of the range and works
downwards.  It means that bumping the maximum means all RPC services
requesting a source port will likely get an unprivileged port instead
of a privileged one.

Changing this setting effects all NFS mount points on a client.  A
sysadmin could not selectively choose which mount points would use
non-privileged ports and which could not.

Lastly, this mechanism of expanding the limit on the number of NFS
mount points was entirely undocumented.

To address the need for the NFS client to use a large range of source
ports without interfering with the activity of other in-kernel RPC
services, we introduce a new NFS mount option.  This option explicitly
tells only the NFS client to use a non-privileged source port when
communicating with the NFS server for one specific mount point.

This new mount option is called "resvport," like the similar NFS mount
option on FreeBSD and Mac OS X.  A sister patch for nfs-utils will be
submitted that documents this new option in nfs(5).

The default setting for this new mount option requires the NFS client
to use a privileged port, as before.  Explicitly specifying the
"noresvport" mount option allows the NFS client to use an unprivileged
source port for this mount point when connecting to the NFS server
port.

This mount option is supported only for text-based NFS mounts.

[ Sidebar: it is widely known that security mechanisms based on the
  use of privileged source ports are ineffective.  However, the NFS
  client can combine the use of unprivileged ports with the use of
  secure authentication mechanisms, such as Kerberos.  This allows a
  large number of connections and mount points while ensuring a useful
  level of security.

  Eventually we may change the default setting for this option
  depending on the security flavor used for the mount.  For example,
  if the mount is using only AUTH_SYS, then the default setting will
  be "resvport;" if the mount is using a strong security flavor such
  as krb5, the default setting will be "noresvport." ]
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
[Trond.Myklebust@netapp.com: Fixed a bug whereby nfs4_init_client()
was being called with incorrect arguments.]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      d740351b
    • C
      NFS: move nfs_server flag initialization · 542fcc33
      由 Chuck Lever 提交于 
      Make it possible for the NFSv4 mount set up logic to pass mount option
flags down the stack to nfs_create_rpc_client().

This is immediately useful if we want NFS mount options to modulate
settings of the underlying RPC transport, but it may be useful at some
later point if other parts of the NFSv4 mount initialization logic
want to know what the mount options are.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      542fcc33
    • C
      NFS: expand flags passed to nfs_create_rpc_client() · 4a01b8a4
      由 Chuck Lever 提交于 
      The nfs_create_rpc_client() function sets up an RPC client for an NFS
mount point.  Add an option that allows it to set up an RPC transport
from an unprivileged port.

Instead of having nfs_create_rpc_client()'s callers retain local
knowledge about how to set up an RPC client, create a couple of flag
arguments to control the use of RPC_CLNT_CREATE flags.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      4a01b8a4
  3. 08 10月, 2008 1 次提交
  5. 07 10月, 2008 1 次提交
  7. 10 7月, 2008 1 次提交
  9. 17 5月, 2008 1 次提交
  11. 29 4月, 2008 2 次提交
  13. 20 4月, 2008 1 次提交
  15. 20 3月, 2008 2 次提交
    • C
      NFS: Save the values of the "mount*=" mount options · 3f8400d1
      由 Chuck Lever 提交于 
      Save the value of the mountproto= mountport= mountvers= and mountaddr=
options so that these values can be displayed later via
nfs_show_options().

This preserves the intent of the original mount options, should the file
system need to be remounted based on what's displayed in /proc/mounts.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      3f8400d1
    • C
      NFS: Save the value of the "port=" mount option · f22d6d79
      由 Chuck Lever 提交于 
      During a remount based on the mount options displayed in /proc/mounts, we
want to preserve the original behavior of the mount request.  Let's save
the original setting of the "port=" mount option in the mount's nfs_server
structure.

This allows us to simplify the default behavior of port setting for NFSv4
mounts: by default, NFSv2/3 mounts first try an RPC bind to determine the
NFS server's port, unless the user specified the "port=" mount option;
Users can force the client to skip the RPC bind by explicitly specifying
"port=<value>".

NFSv4, by contrast, assumes the NFS server port is 2049 and skips the RPC
bind, unless the user specifies "port=".  Users can force an RPC bind for
NFSv4 by explicitly specifying "port=0".

I added a couple of extra comments to clarify this behavior.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      f22d6d79
  17. 29 2月, 2008 1 次提交
  19. 30 1月, 2008 19 次提交
  21. 12 12月, 2007 1 次提交
    • T
      NFSv2/v3: Fix a memory leak when using -onolock · 5cef338b
      由 Trond Myklebust 提交于 
      Neil Brown said:
> Hi Trond,
> 
> We found that a machine which made moderately heavy use of
> 'automount' was leaking some nfs data structures - particularly the
> 4K allocated by rpc_alloc_iostats.
> It turns out that this only happens with filesystems with -onolock
> set.

> The problem is that if NFS_MOUNT_NONLM is set, nfs_start_lockd doesn't
> set server->destroy, so when the filesystem is unmounted, the
> ->client_acl is not shutdown, and so several resources are still
> held.  Multiple mount/umount cycles will slowly eat away memory
> several pages at a time.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NNeilBrown <neilb@suse.de>
      5cef338b
  23. 07 12月, 2007 1 次提交
  25. 17 10月, 2007 1 次提交
  27. 10 10月, 2007 4 次提交
  29. 29 9月, 2007 1 次提交