The struct nfs_server gets put on the cl_superblocks list before
the server->super field has been initialised, in which case the
call to nfs_sb_active() will Oops. Add a check to ensure that
we skip such a list entry.

Fixes: 3c9e502b ("NFS: Add a helper nfs_client_for_each_server()")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

When using NFSv4.2, the security label for the root inode should be set
via a call to nfs_setsecurity() during the mount process, otherwise the
inode will appear as unlabeled for up to acdirmin seconds.  Currently
the label for the root inode is allocated, retrieved, and freed entirely
witin nfs4_proc_get_root().

Add a field for the label to the nfs_fattr struct, and allocate & free
the label in nfs_get_root(), where we also add a call to
nfs_setsecurity().  Note that for the call to nfs_setsecurity() to
succeed, it's necessary to also move the logic calling
security_sb_{set,clone}_security() from nfs_get_tree_common() down into
nfs_get_root()... otherwise the SBLABEL_MNT flag will not be set in the
super_block's security flags and nfs_setsecurity() will silently fail.
Reported-by: NRichard Haines <richard_c_haines@btinternet.com>
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Acked-by: NStephen Smalley <sds@tycho.nsa.gov>
Tested-by: NStephen Smalley <sds@tycho.nsa.gov>
[PM: fixed 80-char line width problems]
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Add a helper nfs_client_for_each_server() to iterate through all the
filesystems that are attached to a struct nfs_client, and apply
a function to all the active ones.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Add a mount option 'softreval' that allows attribute revalidation 'getattr'
calls to time out, and causes them to fall back to using the cached
attributes.
The use case for this option is for ensuring that we can still (slowly)
traverse paths and use cached information even when the server is down.
Once the server comes back up again, the getattr calls start succeeding,
and the caches will revalidate as usual.

The 'softreval' mount option is automatically enabled if you have
specified 'softerr'.  It can be turned off using the options
'nosoftreval', or 'hard'.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Split out from commit "NFS: Add fs_context support."

Add wrappers nfs_errorf(), nfs_invalf(), and nfs_warnf() which log error
information to the fs_context.  Convert some printk's to use these new
wrappers instead.
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Split out from commit "NFS: Add fs_context support."

This patch adds additional refactoring for the conversion of NFS to use
fs_context, namely:

 (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context.
     nfs_clone_mount has had several fields removed, and nfs_mount_info
     has been removed altogether.
 (*) Various functions now take an fs_context as an argument instead
     of nfs_mount_info, nfs_fs_context, etc.
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Add filesystem context support to NFS, parsing the options in advance and
attaching the information to struct nfs_fs_context.  The highlights are:

 (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context.  This
     structure represents NFS's superblock config.

 (*) Make use of the VFS's parsing support to split comma-separated lists

 (*) Pin the NFS protocol module in the nfs_fs_context.

 (*) Attach supplementary error information to fs_context.  This has the
     downside that these strings must be static and can't be formatted.

 (*) Remove the auxiliary file_system_type structs since the information
     necessary can be conveyed in the nfs_fs_context struct instead.

 (*) Root mounts are made by duplicating the config for the requested mount
     so as to have the same parameters.  Submounts pick up their parameters
     from the parent superblock.

[AV -- retrans is u32, not string]
[SM -- Renamed cfg to ctx in a few functions in an earlier patch]
[SM -- Moved fs_context mount option parsing to an earlier patch]
[SM -- Moved fs_context error logging to a later patch]
[SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()]
[SM -- Added is_remount_fc() helper]
[SM -- Deferred some refactoring to a later patch]
[SM -- Fixed referral mounts, which were broken in the original patch]
[SM -- Fixed leak of nfs_fattr when fs_context is freed]
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Split out from commit "NFS: Add fs_context support."

Rename cfg to ctx in nfs_init_server(), nfs_verify_authflavors(),
and nfs_request_mount().  No functional changes.
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Do some tidying of the parsing code, including:

 (*) Returning 0/error rather than true/false.

 (*) Putting the nfs_fs_context pointer first in some arg lists.

 (*) Unwrap some lines that will now fit on one line.

 (*) Provide unioned sockaddr/sockaddr_storage fields to avoid casts.

 (*) nfs_parse_devname() can paste its return values directly into the
     nfs_fs_context struct as that's where the caller puts them.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Rename struct nfs_parsed_mount_data to struct nfs_fs_context and rename
pointers to it to "ctx".  At some point this will be pointed to by an
fs_context struct's fs_private pointer.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Split various bits relating to mount parameterisation out from
fs/nfs/super.c into their own file to form the basis of filesystem context
handling for NFS.

No other changes are made to the code beyond removing 'static' qualifiers.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

it's always either nfs_set_sb_security() or nfs_clone_sb_security(),
the choice being controlled by mount_info->cloned != NULL.  No need
to add methods, especially when both instances live right next to
the caller and are never accessed anywhere else.
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

We used to check ->i_op for being nfs_dir_inode_operations.  With
separate inode_operations for v3 and v4 that became bogus, but
rather than going for protocol-dependent comparison we could've
just checked ->i_fop instead; _that_ is the same for all protocol
versions.
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

The only possible values are nfs_fill_super and nfs_clone_super.  The
latter is used only when crossing into a submount and it is almost
identical to the former; the only differences are
	* ->s_time_gran unconditionally set to 1 (even for v2 mounts).
Regression dating back to 2012, actually.
	* ->s_blocksize/->s_blocksize_bits set to that of parent.

Rather than messing with the method, stash ->s_blocksize_bits in
mount_info in submount case and after the (now unconditional)
call of nfs_fill_super() override ->s_blocksize/->s_blocksize_bits
if that has been set.
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

pick it from mount_info
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Make it static, even.  And remove a stale extern of (long-gone)
nfs_xdev_mount_common() from internal.h, while we are at it.
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

they are identical now...
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

That will allow to get rid of passing those references around in
quite a few places.  Moreover, that will allow to merge xdev and
remote file_system_type.
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Do it in nfs_do_submount() instead.  As a side benefit, nfs_clone_data
doesn't need ->fh and ->fattr anymore.
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Allow it to take ERR_PTR() for server and return ERR_CAST() of it in
such case.  All callers used to open-code that...
Reviewed-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

remove unneeded semicolon.
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

In the years since the max readahead size was fixed in NFS, a number of
things have happened:
- Users can now set the value directly using /sys/class/bdi
- NFS max supported block sizes have increased by several orders of
  magnitude from 64K to 1MB.
- Disk access latencies are orders of magnitude faster due to SSD + NVME.

In particular note that if the server is advertising 1MB as the optimal
read size, as that will set the readahead size to 15MB.
Let's therefore adjust down, and try to default to VM_READAHEAD_PAGES.
However let's inform the VM about our preferred block size so that it
can choose to round up in cases where that makes sense.
Reported-by: NAlkis Georgopoulos <alkisg@gmail.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Fill in the appropriate limits to avoid inconsistencies
in the vfs cached inode times when timestamps are
outside the permitted range.

The time formats for various verious is detailed in the
RFCs as below:

https://tools.ietf.org/html/rfc7862(time metadata)
https://tools.ietf.org/html/rfc7530:

nfstime4

   struct nfstime4 {
           int64_t         seconds;
           uint32_t        nseconds;
   };

https://tools.ietf.org/html/rfc1094

          struct timeval {
              unsigned int seconds;
              unsigned int useconds;
          };

https://tools.ietf.org/html/rfc1813

struct nfstime3 {
         uint32   seconds;
         uint32   nseconds;
      };

Use the limits as per the RFC.
Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com>
Acked-by: NJeff Layton <jlayton@kernel.org>
Cc: trond.myklebust@hammerspace.com
Cc: anna.schumaker@netapp.com
Cc: linux-nfs@vger.kernel.org

People are reporing seeing fscache errors being reported concerning
duplicate cookies even in cases where they are not setting up fscache
at all. The rule needs to be that if fscache is not enabled, then it
should have no side effects at all.

To ensure this is the case, we disable fscache completely on all superblocks
for which the 'fsc' mount option was not set. In order to avoid issues
with '-oremount', we also disable the ability to turn fscache on via
remount.

Fixes: f1fe29b4 ("NFS: Use i_writecount to control whether...")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200145Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Cc: Steve Dickson <steved@redhat.com>
Cc: David Howells <dhowells@redhat.com>

Some strings should be put into a sequence.
Thus use the corresponding function “seq_puts”.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

A single character (line break) should be put into a sequence.
Thus use the corresponding function “seq_putc”.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

On the NFS client there is no low-impact way to determine the nfs4
lease time or whether the lease is expired, so add these to mountstats
with times displayed in seconds.

If the lease is not expired, display lease_expired=0. Otherwise,
display lease_expired=seconds_since_expired, similar to 'age:' line
in mountstats.
Signed-off-by: NDave Wysochanski <dwysocha@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Allow the user to specify that the client should use multiple connections
to the server. For the moment, this functionality will be limited to
TCP and to NFSv4.x (x>0).
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

If two different containers that share the same network namespace attempt
to mount the same filesystem, we should not allow them to share the same
super block if they do not share the same user namespace, since the
user mappings on the wire will need to differ.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Add a mount option that exposes the ETIMEDOUT errors that occur during
soft timeouts to the application. This allows aware applications to
distinguish between server disk IO errors and client timeout errors.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

syzbot is reporting uninitialized value at rpc_sockaddr2uaddr() [1]. This
is because syzbot is setting AF_INET6 to "struct sockaddr_in"->sin_family
(which is embedded into user-visible "struct nfs_mount_data" structure)
despite nfs23_validate_mount_data() cannot pass sizeof(struct sockaddr_in6)
bytes of AF_INET6 address to rpc_sockaddr2uaddr().

Since "struct nfs_mount_data" structure is user-visible, we can't change
"struct nfs_mount_data" to use "struct sockaddr_storage". Therefore,
assuming that everybody is using AF_INET family when passing address via
"struct nfs_mount_data"->addr, reject if its sin_family is not AF_INET.

[1] https://syzkaller.appspot.com/bug?id=599993614e7cbbf66bc2656a919ab2a95fb5d75cReported-by: Nsyzbot <syzbot+047a11c361b872896a4f@syzkaller.appspotmail.com>
Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

In the rare and unsupported case of a hostname list nfs_parse_devname
will modify dev_name.  There is no need to modify dev_name as the all
that is being computed is the length of the hostname, so the computed
length can just be shorted.

Fixes: dc045898 ("NFS: Use common device name parsing logic for NFSv4 and NFSv2/v3")
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

There is a NULL pointer dereference of dev_name in nfs_parse_devname()

The oops looks something like:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
  ...
  RIP: 0010:nfs_fs_mount+0x3b6/0xc20 [nfs]
  ...
  Call Trace:
   ? ida_alloc_range+0x34b/0x3d0
   ? nfs_clone_super+0x80/0x80 [nfs]
   ? nfs_free_parsed_mount_data+0x60/0x60 [nfs]
   mount_fs+0x52/0x170
   ? __init_waitqueue_head+0x3b/0x50
   vfs_kern_mount+0x6b/0x170
   do_mount+0x216/0xdc0
   ksys_mount+0x83/0xd0
   __x64_sys_mount+0x25/0x30
   do_syscall_64+0x65/0x220
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fix this by adding a NULL check on dev_name
Signed-off-by: NYao Liu <yotta.liu@ucloud.cn>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Having to specify "proto=rdma,port=20049" is cumbersome.

RFC 8267 Section 6.3 requires NFSv4 clients to use "the alternative
well-known port number", which is 20049. Make the use of the well-
known port number automatic, just as it is for NFS/TCP and port
2049.

For NFSv2/3, Section 4.2 allows clients to simply choose 20049 as
the default or use rpcbind. I don't know of an NFS/RDMA server
implementation that registers it's NFS/RDMA service with rpcbind,
so automatically choosing 20049 seems like the better choice. The
other widely-deployed NFS/RDMA client, Solaris, also uses 20049
as the default port.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>