The marquee feature for this release is that the limit on the
maximum rsize and wsize has been raised to 4MB. The default remains
at 1MB, but risk-seeking administrators now have the ability to try
larger I/O sizes with NFS clients that support them. Eventually the
default setting will be increased when we have confidence that this
change will not have negative impact.
With v6.16, NFSD now has its own debugfs file system where we can
add experimental features and make them available outside of our
development community without impacting production deployments. The
first experimental setting added is one that makes all NFS READ
operations use vfs_iter_read() instead of the NFSD splice actor. The
plan is to eventually retire the splice actor, as that will enable a
number of new capabilities such as the use of struct bio_vec from the
top to the bottom of the NFSD stack.
Jeff Layton contributed a number of observability improvements. The
use of dprintk() in a number of high-traffic code paths has been
replaced with static trace points.
This release sees the continuation of efforts to harden the NFSv4.2
COPY operation. Soon, the restriction on async COPY operations can
be lifted.
Many thanks to the contributors, reviewers, testers, and bug
reporters who participated during the v6.16 development cycle.
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Merge tag 'nfsd-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull nfsd updates from Chuck Lever:
"The marquee feature for this release is that the limit on the maximum
rsize and wsize has been raised to 4MB. The default remains at 1MB,
but risk-seeking administrators now have the ability to try larger I/O
sizes with NFS clients that support them. Eventually the default
setting will be increased when we have confidence that this change
will not have negative impact.
With v6.16, NFSD now has its own debugfs file system where we can add
experimental features and make them available outside of our
development community without impacting production deployments. The
first experimental setting added is one that makes all NFS READ
operations use vfs_iter_read() instead of the NFSD splice actor. The
plan is to eventually retire the splice actor, as that will enable a
number of new capabilities such as the use of struct bio_vec from the
top to the bottom of the NFSD stack.
Jeff Layton contributed a number of observability improvements. The
use of dprintk() in a number of high-traffic code paths has been
replaced with static trace points.
This release sees the continuation of efforts to harden the NFSv4.2
COPY operation. Soon, the restriction on async COPY operations can be
lifted.
Many thanks to the contributors, reviewers, testers, and bug reporters
who participated during the v6.16 development cycle"
* tag 'nfsd-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (60 commits)
xdrgen: Fix code generated for counted arrays
SUNRPC: Bump the maximum payload size for the server
NFSD: Add a "default" block size
NFSD: Remove NFSSVC_MAXBLKSIZE_V2 macro
NFSD: Remove NFSD_BUFSIZE
sunrpc: Remove the RPCSVC_MAXPAGES macro
svcrdma: Adjust the number of entries in svc_rdma_send_ctxt::sc_pages
svcrdma: Adjust the number of entries in svc_rdma_recv_ctxt::rc_pages
sunrpc: Adjust size of socket's receive page array dynamically
SUNRPC: Remove svc_rqst :: rq_vec
SUNRPC: Remove svc_fill_write_vector()
NFSD: Use rqstp->rq_bvec in nfsd_iter_write()
SUNRPC: Export xdr_buf_to_bvec()
NFSD: De-duplicate the svc_fill_write_vector() call sites
NFSD: Use rqstp->rq_bvec in nfsd_iter_read()
sunrpc: Replace the rq_bvec array with dynamically-allocated memory
sunrpc: Replace the rq_pages array with dynamically-allocated memory
sunrpc: Remove backchannel check in svc_init_buffer()
sunrpc: Add a helper to derive maxpages from sv_max_mesg
svcrdma: Reduce the number of rdma_rw contexts per-QP
...
If we can get rid of all uses of rq_vec, then it can be removed.
Replace one use of rqstp::rq_vec with rqstp::rq_bvec.
The feeling of layering violation grows stronger now that
<linux/sunrpc/xdr.h> is included in fs/nfsd/vfs.c.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
All three call sites do the same thing.
I'm struggling with this a bit, however. struct xdr_buf is an XDR
layer object and unmarshaling a WRITE payload is clearly a task
intended to be done by the proc and xdr functions, not by VFS. This
feels vaguely like a layering violation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
If we can get rid of all uses of rq_vec, then it can be removed.
Replace one use of rqstp::rq_vec with rqstp::rq_bvec.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
There isn't a common helper for getattrs, so add these into the
protocol-specific helpers.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Observe the start of RENAME operations for all NFS versions.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Observe the start of UNLINK, REMOVE, and RMDIR operations for all
NFS versions.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Observe the start of SYMLINK operations for all NFS versions.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Observe the start of file and directory creation for all NFS
versions.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Replace the dprintk in nfsd_lookup_dentry() with a trace point.
nfsd_lookup_dentry() is called frequently enough that enabling this
dprintk call site would result in log floods and performance issues.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Turn Sargun's internal kprobe based implementation of this into a normal
static tracepoint. Also, remove the dprintk's that got added recently
with the fix for zero-length ACLs.
Cc: Sargun Dillon <sargun@sargun.me>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Very useful for gauging how long the vfs_fsync_range() takes.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
NFSD currently has two separate code paths for handling read
requests. One uses page splicing; the other is a traditional read
based on an iov iterator.
Because most Linux file systems support splice read, the latter
does not get nearly the same test experience as splice reads.
To force the use of vectored reads for testing and benchmarking,
introduce the ability to disable splice reads for all NFS READ
operations.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nfsd uses some VFS interfaces (such as vfs_mkdir) which take an explicit
mnt_idmap, and it passes &nop_mnt_idmap as nfsd doesn't yet support
idmapped mounts.
It also uses the lookup_one_len() family of functions which implicitly
use &nop_mnt_idmap. This mixture of implicit and explicit could be
confusing. When we eventually update nfsd to support idmap mounts it
would be best if all places which need an idmap determined from the
mount point were similar and easily found.
So this patch changes nfsd to use lookup_one(), lookup_one_unlocked(),
and lookup_one_positive_unlocked(), passing &nop_mnt_idmap.
This has the benefit of removing some uses of the lookup_one_len
functions where permission checking is actually needed. Many callers
don't care about permission checking and using these function only where
permission checking is needed is a valuable simplification.
This change requires passing the name in a qstr. Currently this is a
little clumsy, but if nfsd is changed to use qstr more broadly it will
result in a net improvement.
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://lore.kernel.org/r/20250319031545.2999807-3-neil@brown.name
Signed-off-by: Christian Brauner <brauner@kernel.org>
Neil Brown contributed more scalability improvements to NFSD's
open file cache, and Jeff Layton contributed a menagerie of
repairs to NFSD's NFSv4 callback / backchannel implementation.
Mike Snitzer contributed a change to NFS re-export support that
disables support for file locking on a re-exported NFSv4 mount.
This is because NFSv4 state recovery is currently difficult if
not impossible for re-exported NFS mounts. The change aims to
prevent data integrity exposures after the re-export server
crashes.
Work continues on the evolving NFSD netlink administrative API.
Many thanks to the contributors, reviewers, testers, and bug
reporters who participated during the v6.15 development cycle.
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Merge tag 'nfsd-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull nfsd updates from Chuck Lever:
"Neil Brown contributed more scalability improvements to NFSD's open
file cache, and Jeff Layton contributed a menagerie of repairs to
NFSD's NFSv4 callback / backchannel implementation.
Mike Snitzer contributed a change to NFS re-export support that
disables support for file locking on a re-exported NFSv4 mount. This
is because NFSv4 state recovery is currently difficult if not
impossible for re-exported NFS mounts. The change aims to prevent data
integrity exposures after the re-export server crashes.
Work continues on the evolving NFSD netlink administrative API.
Many thanks to the contributors, reviewers, testers, and bug reporters
who participated during the v6.15 development cycle"
* tag 'nfsd-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (45 commits)
NFSD: Add a Kconfig setting to enable delegated timestamps
sysctl: Fixes nsm_local_state bounds
nfsd: use a long for the count in nfsd4_state_shrinker_count()
nfsd: remove obsolete comment from nfs4_alloc_stid
nfsd: remove unneeded forward declaration of nfsd4_mark_cb_fault()
nfsd: reorganize struct nfs4_delegation for better packing
nfsd: handle errors from rpc_call_async()
nfsd: move cb_need_restart flag into cb_flags
nfsd: replace CB_GETATTR_BUSY with NFSD4_CALLBACK_RUNNING
nfsd: eliminate cl_ra_cblist and NFSD4_CLIENT_CB_RECALL_ANY
nfsd: prevent callback tasks running concurrently
nfsd: disallow file locking and delegations for NFSv4 reexport
nfsd: filecache: drop the list_lru lock during lock gc scans
nfsd: filecache: don't repeatedly add/remove files on the lru list
nfsd: filecache: introduce NFSD_FILE_RECENT
nfsd: filecache: use list_lru_walk_node() in nfsd_file_gc()
nfsd: filecache: use nfsd_file_dispose_list() in nfsd_file_close_inode_sync()
NFSD: Re-organize nfsd_file_gc_worker()
nfsd: filecache: remove race handling.
fs: nfs: acl: Avoid -Wflex-array-member-not-at-end warning
...
RFC 8881 Section 18.9.4 paragraphs 1 - 2 tell us that RENAME should
return NFS4ERR_FILE_OPEN only when the target object is a file that
is currently open. If the target is a directory, some other status
must be returned.
The VFS is unlikely to return -EBUSY, but NFSD has to ensure that
errno does not leak to clients as a status code that is not
permitted by spec.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
RFC 8881 Section 18.26.4 paragraphs 1 - 3 tell us that RENAME should
return NFS4ERR_FILE_OPEN only when the target object is a file that
is currently open. If the target is a directory, some other status
must be returned.
Generally I expect that a delegation recall will be triggered in
some of these circumstances. In other cases, the VFS might return
-EBUSY for other reasons, and NFSD has to ensure that errno does
not leak to clients as a status code that is not permitted by spec.
There are some error flows where the target dentry hasn't been
found yet. The default value for @type therefore is S_IFDIR to return
an alternate status code in those cases.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
RFC 8881 Section 18.25.4 paragraph 5 tells us that the server
should return NFS4ERR_FILE_OPEN only if the target object is an
opened file. This suggests that returning this status when removing
a directory will confuse NFS clients.
This is a version-specific issue; nfsd_proc_remove/rmdir() and
nfsd3_proc_remove/rmdir() already return nfserr_access as
appropriate.
Unfortunately there is no quick way for nfsd4_remove() to determine
whether the target object is a file or not, so the check is done in
in nfsd_unlink() for now.
Reported-by: Trond Myklebust <trondmy@hammerspace.com>
Fixes: 466e16f092 ("nfsd: check for EBUSY from vfs_rmdir/vfs_unink.")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
If fh_fill_pre_attrs() returns a non-zero status, the error flow
takes it through out_unlock, which then overwrites the returned
status code with
err = nfserrno(host_err);
Fixes: a332018a91 ("nfsd: handle failure to collect pre/post-op attrs more sanely")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
There two mappings of nfserr_mlink in nfs_errtbl.
Remove one of them.
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
vfs_mkdir() does not guarantee to leave the child dentry hashed or make
it positive on success, and in many such cases the filesystem had to use
a different dentry which it can now return.
This patch changes vfs_mkdir() to return the dentry provided by the
filesystems which is hashed and positive when provided. This reduces
the number of cases where the resulting dentry is not positive to a
handful which don't deserve extra efforts.
The only callers of vfs_mkdir() which are interested in the resulting
inode are in-kernel filesystem clients: cachefiles, nfsd, smb/server.
The only filesystems that don't reliably provide the inode are:
- kernfs, tracefs which these clients are unlikely to be interested in
- cifs in some configurations would need to do a lookup to find the
created inode, but doesn't. cifs cannot be exported via NFS, is
unlikely to be used by cachefiles, and smb/server only has a soft
requirement for the inode, so this is unlikely to be a problem in
practice.
- hostfs, nfs, cifs may need to do a lookup (rarely for NFS) and it is
possible for a race to make that lookup fail. Actual failure
is unlikely and providing callers handle negative dentries graceful
they will fail-safe.
So this patch removes the lookup code in nfsd and smb/server and adjusts
them to fail safe if a negative dentry is provided:
- cache-files already fails safe by restarting the task from the
top - it still does with this change, though it no longer calls
cachefiles_put_directory() as that will crash if the dentry is
negative.
- nfsd reports "Server-fault" which it what it used to do if the lookup
failed. This will never happen on any file-systems that it can actually
export, so this is of no consequence. I removed the fh_update()
call as that is not needed and out-of-place. A subsequent
nfsd_create_setattr() call will call fh_update() when needed.
- smb/server only wants the inode to call ksmbd_smb_inherit_owner()
which updates ->i_uid (without calling notify_change() or similar)
which can be safely skipping on cifs (I hope).
If a different dentry is returned, the first one is put. If necessary
the fact that it is new can be determined by comparing pointers. A new
dentry will certainly have a new pointer (as the old is put after the
new is obtained).
Similarly if an error is returned (via ERR_PTR()) the original dentry is
put.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20250227013949.536172-7-neilb@suse.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
nfsd_create_locked() doesn't need to explicitly call fh_update().
On success (which is the only time that fh_update() matters at all),
nfsd_create_setattr() will be called and it will call fh_update().
This extra call is not harmful, but is not necessary.
Signed-off-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20250226062135.2043651-3-neilb@suse.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
added back in 2015 for the sake of vfs_clone_file_range(),
which is in linux/fs.h these days
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
NFSD_MAY_LOCK means a few different things.
- it means that GSS is not required.
- it means that with NFSEXP_NOAUTHNLM, authentication is not required
- it means that OWNER_OVERRIDE is allowed.
None of these are specific to locking, they are specific to the NLM
protocol.
So:
- rename to NFSD_MAY_NLM
- set NFSD_MAY_OWNER_OVERRIDE and NFSD_MAY_BYPASS_GSS in nlm_fopen()
so that NFSD_MAY_NLM doesn't need to imply these.
- move the test on NFSEXP_NOAUTHNLM out of nfsd_permission() and
into fh_verify where other special-case tests on the MAY flags
happen. nfsd_permission() can be called from other places than
fh_verify(), but none of these will have NFSD_MAY_NLM.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Currently NFSD_MAY_BYPASS_GSS and NFSD_MAY_BYPASS_GSS_ON_ROOT do not bypass
only GSS, but bypass any method. This is a problem specially for NFS3
AUTH_NULL-only exports.
The purpose of NFSD_MAY_BYPASS_GSS_ON_ROOT is described in RFC 2623,
section 2.3.2, to allow mounting NFS2/3 GSS-only export without
authentication. So few procedures which do not expose security risk used
during mount time can be called also with AUTH_NONE or AUTH_SYS, to allow
client mount operation to finish successfully.
The problem with current implementation is that for AUTH_NULL-only exports,
the NFSD_MAY_BYPASS_GSS_ON_ROOT is active also for NFS3 AUTH_UNIX mount
attempts which confuse NFS3 clients, and make them think that AUTH_UNIX is
enabled and is working. Linux NFS3 client never switches from AUTH_UNIX to
AUTH_NONE on active mount, which makes the mount inaccessible.
Fix the NFSD_MAY_BYPASS_GSS and NFSD_MAY_BYPASS_GSS_ON_ROOT implementation
and really allow to bypass only exports which have enabled some real
authentication (GSS, TLS, or any other).
The result would be: For AUTH_NULL-only export if client attempts to do
mount with AUTH_UNIX flavor then it will receive access errors, which
instruct client that AUTH_UNIX flavor is not usable and will either try
other auth flavor (AUTH_NULL if enabled) or fails mount procedure.
Similarly if client attempt to do mount with AUTH_NULL flavor and only
AUTH_UNIX flavor is enabled then the client will receive access error.
This should fix problems with AUTH_NULL-only or AUTH_UNIX-only exports if
client attempts to mount it with other auth flavor (e.g. with AUTH_NULL for
AUTH_UNIX-only export, or with AUTH_UNIX for AUTH_NULL-only export).
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clean up: Commit 65294c1f2c ("nfsd: add a new struct file caching
facility to nfsd") moved the fh_verify() call site out of
nfsd_open(). That was the only user of nfsd_open's @rqstp parameter,
so that parameter can be removed.
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
I noticed that recently, simple operations like "make" started
failing on NFSv3 mounts of ext4 exports. Network capture shows that
READDIRPLUS operated correctly but READDIR failed with
NFS3ERR_INVAL. The vfs_llseek() call returned EINVAL when it is
passed a non-zero starting directory cookie.
I bisected to commit c689bdd3bf ("nfsd: further centralize
protocol version checks.").
Turns out that nfsd3_proc_readdir() does not call fh_verify() before
it calls nfsd_readdir(), so the new fhp->fh_64bit_cookies boolean is
not set properly. This leaves the NFSD_MAY_64BIT_COOKIE unset when
the directory is opened.
For ext4, this causes the wrong "max file size" value to be used
when sanity checking the incoming directory cookie (which is a seek
offset value).
The fhp->fh_64bit_cookies boolean is /always/ properly initialized
after nfsd_open() returns. There doesn't seem to be a reason for the
generic NFSD open helper to handle the f_mode fix-up for
directories, so just move that to the one caller that tries to open
an S_IFDIR with NFSD_MAY_64BIT_COOKIE.
Suggested-by: NeilBrown <neilb@suse.de>
Fixes: c689bdd3bf ("nfsd: further centralize protocol version checks.")
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
There is code scattered around nfsd which chooses an error status based
on the particular version of nfs being used. It is cleaner to have the
version specific choices in version specific code.
With this patch common code returns the most specific error code
possible and the version specific code maps that if necessary.
Both v2 (nfsproc.c) and v3 (nfs3proc.c) now have a "map_status()"
function which is called to map the resp->status before each non-trivial
nfsd_proc_* or nfsd3_proc_* function returns.
NFS4ERR_SYMLINK and NFS4ERR_WRONG_TYPE introduce extra complications and
are left for a later patch.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
With this patch the only places that test ->rq_vers against a specific
version are nfsd_v4client() and nfsd_set_fh_dentry().
The latter sets some flags in the svc_fh, which now includes:
fh_64bit_cookies
fh_use_wgather
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nfsd_permission(), exp_rdonly(), nfsd_setuser(), and nfsexp_flags()
only ever need the cred out of rqstp, so pass it explicitly instead of
the whole rqstp.
This makes the interfaces cleaner.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
When security labeling is enabled, the client can pass a file security
label as part of a create operation for the new file, similar to mode
and other attributes. At present, the security label is received by nfsd
and passed down to nfsd_create_setattr(), but nfsd_setattr() is never
called and therefore the label is never set on the new file. This bug
may have been introduced on or around commit d6a97d3f58 ("NFSD:
add security label to struct nfsd_attrs"). Looking at nfsd_setattr()
I am uncertain as to whether the same issue presents for
file ACLs and therefore requires a similar fix for those.
An alternative approach would be to introduce a new LSM hook to set the
"create SID" of the current task prior to the actual file creation, which
would atomically label the new inode at creation time. This would be better
for SELinux and a similar approach has been used previously
(see security_dentry_create_files_as) but perhaps not usable by other LSMs.
Reproducer:
1. Install a Linux distro with SELinux - Fedora is easiest
2. git clone https://github.com/SELinuxProject/selinux-testsuite
3. Install the requisite dependencies per selinux-testsuite/README.md
4. Run something like the following script:
MOUNT=$HOME/selinux-testsuite
sudo systemctl start nfs-server
sudo exportfs -o rw,no_root_squash,security_label localhost:$MOUNT
sudo mkdir -p /mnt/selinux-testsuite
sudo mount -t nfs -o vers=4.2 localhost:$MOUNT /mnt/selinux-testsuite
pushd /mnt/selinux-testsuite/
sudo make -C policy load
pushd tests/filesystem
sudo runcon -t test_filesystem_t ./create_file -f trans_test_file \
-e test_filesystem_filetranscon_t -v
sudo rm -f trans_test_file
popd
sudo make -C policy unload
popd
sudo umount /mnt/selinux-testsuite
sudo exportfs -u localhost:$MOUNT
sudo rmdir /mnt/selinux-testsuite
sudo systemctl stop nfs-server
Expected output:
<eliding noise from commands run prior to or after the test itself>
Process context:
unconfined_u:unconfined_r:test_filesystem_t:s0-s0:c0.c1023
Created file: trans_test_file
File context: unconfined_u:object_r:test_filesystem_filetranscon_t:s0
File context is correct
Actual output:
<eliding noise from commands run prior to or after the test itself>
Process context:
unconfined_u:unconfined_r:test_filesystem_t:s0-s0:c0.c1023
Created file: trans_test_file
File context: system_u:object_r:test_file_t:s0
File context error, expected:
test_filesystem_filetranscon_t
got:
test_file_t
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Commit a8b0026847 ("rename(): avoid a deadlock in the case of parents
having no common ancestor") added an error bail out path. However this
path does not drop the remount protection that has been acquired. Fix
the cleanup path to properly drop the remount protection.
Fixes: a8b0026847 ("rename(): avoid a deadlock in the case of parents having no common ancestor")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
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Merge tag 'lsm-pr-20240312' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm
Pull lsm updates from Paul Moore:
- Promote IMA/EVM to a proper LSM
This is the bulk of the diffstat, and the source of all the changes
in the VFS code. Prior to the start of the LSM stacking work it was
important that IMA/EVM were separate from the rest of the LSMs,
complete with their own hooks, infrastructure, etc. as it was the
only way to enable IMA/EVM at the same time as a LSM.
However, now that the bulk of the LSM infrastructure supports
multiple simultaneous LSMs, we can simplify things greatly by
bringing IMA/EVM into the LSM infrastructure as proper LSMs. This is
something I've wanted to see happen for quite some time and Roberto
was kind enough to put in the work to make it happen.
- Use the LSM hook default values to simplify the call_int_hook() macro
Previously the call_int_hook() macro required callers to supply a
default return value, despite a default value being specified when
the LSM hook was defined.
This simplifies the macro by using the defined default return value
which makes life easier for callers and should also reduce the number
of return value bugs in the future (we've had a few pop up recently,
hence this work).
- Use the KMEM_CACHE() macro instead of kmem_cache_create()
The guidance appears to be to use the KMEM_CACHE() macro when
possible and there is no reason why we can't use the macro, so let's
use it.
- Fix a number of comment typos in the LSM hook comment blocks
Not much to say here, we fixed some questionable grammar decisions in
the LSM hook comment blocks.
* tag 'lsm-pr-20240312' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (28 commits)
cred: Use KMEM_CACHE() instead of kmem_cache_create()
lsm: use default hook return value in call_int_hook()
lsm: fix typos in security/security.c comment headers
integrity: Remove LSM
ima: Make it independent from 'integrity' LSM
evm: Make it independent from 'integrity' LSM
evm: Move to LSM infrastructure
ima: Move IMA-Appraisal to LSM infrastructure
ima: Move to LSM infrastructure
integrity: Move integrity_kernel_module_request() to IMA
security: Introduce key_post_create_or_update hook
security: Introduce inode_post_remove_acl hook
security: Introduce inode_post_set_acl hook
security: Introduce inode_post_create_tmpfile hook
security: Introduce path_post_mknod hook
security: Introduce file_release hook
security: Introduce file_post_open hook
security: Introduce inode_post_removexattr hook
security: Introduce inode_post_setattr hook
security: Align inode_setattr hook definition with EVM
...
Add an explanation to prevent the future removal of the fill-
attribute call sites in nfsd_setattr(). Some NFSv3 client
implementations don't behave correctly if wcc data is not present in
an NFSv3 SETATTR reply.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The main point of the guarded SETATTR is to prevent races with other
WRITE and SETATTR calls. That requires that the check of the guard time
against the inode ctime be done after taking the inode lock.
Furthermore, we need to take into account the 32-bit nature of
timestamps in NFSv3, and the possibility that files may change at a
faster rate than once a second.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Commit bb4d53d66e ("NFSD: use (un)lock_inode instead of
fh_(un)lock for file operations") broke the NFSv3 pre/post op
attributes behaviour when doing a SETATTR rpc call by stripping out
the calls to fh_fill_pre_attrs() and fh_fill_post_attrs().
Fixes: bb4d53d66e ("NFSD: use (un)lock_inode instead of fh_(un)lock for file operations")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Message-ID: <20240216012451.22725-1-trondmy@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
We have a global set of counters that we modify for all of the nfsd
operations, but now that we're exposing these stats across all network
namespaces we need to make the stats also be per-network namespace. We
already have some caching stats that are per-network namespace, so move
these definitions into the same counter and then adjust all the helpers
and users of these stats to provide the appropriate nfsd_net struct so
that the stats are maintained for the per-network namespace objects.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Calling fput() directly or though filp_close() from a kernel thread like
nfsd causes the final __fput() (if necessary) to be called from a
workqueue. This means that nfsd is not forced to wait for any work to
complete. If the ->release or ->destroy_inode function is slow for any
reason, this can result in nfsd closing files more quickly than the
workqueue can complete the close and the queue of pending closes can
grow without bounces (30 million has been seen at one customer site,
though this was in part due to a slowness in xfs which has since been
fixed).
nfsd does not need this. It is quite appropriate and safe for nfsd to
do its own close work. There is no reason that close should ever wait
for nfsd, so no deadlock can occur.
It should be safe and sensible to change all fput() calls to
__fput_sync(). However in the interests of caution this patch only
changes two - the two that can be most directly affected by client
behaviour and could occur at high frequency.
- the fput() implicitly in flip_close() is changed to __fput_sync()
by calling get_file() first to ensure filp_close() doesn't do
the final fput() itself. If is where files opened for IO are closed.
- the fput() in nfsd_read() is also changed. This is where directories
opened for readdir are closed.
This ensure that minimal fput work is queued to the workqueue.
This removes the need for the flush_delayed_fput() call in
nfsd_file_close_inode_sync()
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Move hardcoded IMA function calls (not appraisal-specific functions) from
various places in the kernel to the LSM infrastructure, by introducing a
new LSM named 'ima' (at the end of the LSM list and always enabled like
'integrity').
Having IMA before EVM in the Makefile is sufficient to preserve the
relative order of the new 'ima' LSM in respect to the upcoming 'evm' LSM,
and thus the order of IMA and EVM function calls as when they were
hardcoded.
Make moved functions as static (except ima_post_key_create_or_update(),
which is not in ima_main.c), and register them as implementation of the
respective hooks in the new function init_ima_lsm().
Select CONFIG_SECURITY_PATH, to ensure that the path-based LSM hook
path_post_mknod is always available and ima_post_path_mknod() is always
executed to mark files as new, as before the move.
A slight difference is that IMA and EVM functions registered for the
inode_post_setattr, inode_post_removexattr, path_post_mknod,
inode_post_create_tmpfile, inode_post_set_acl and inode_post_remove_acl
won't be executed for private inodes. Since those inodes are supposed to be
fs-internal, they should not be of interest to IMA or EVM. The S_PRIVATE
flag is used for anonymous inodes, hugetlbfs, reiserfs xattrs, XFS scrub
and kernel-internal tmpfs files.
Conditionally register ima_post_key_create_or_update() if
CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is enabled. Also, conditionally register
ima_kernel_module_request() if CONFIG_INTEGRITY_ASYMMETRIC_KEYS is enabled.
Finally, add the LSM_ID_IMA case in lsm_list_modules_test.c.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
In preparation to move IMA and EVM to the LSM infrastructure, introduce the
file_post_open hook. Also, export security_file_post_open() for NFS.
Based on policy, IMA calculates the digest of the file content and
extends the TPM with the digest, verifies the file's integrity based on
the digest, and/or includes the file digest in the audit log.
LSMs could similarly take action depending on the file content and the
access mask requested with open().
The new hook returns a value and can cause the open to be aborted.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
broken in 6.5; we really can't lock two unrelated directories
without holding ->s_vfs_rename_mutex first and in case of
same-parent rename of a subdirectory 6.5 ends up doing just
that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull rename updates from Al Viro:
"Fix directory locking scheme on rename
This was broken in 6.5; we really can't lock two unrelated directories
without holding ->s_vfs_rename_mutex first and in case of same-parent
rename of a subdirectory 6.5 ends up doing just that"
* tag 'pull-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
rename(): avoid a deadlock in the case of parents having no common ancestor
kill lock_two_inodes()
rename(): fix the locking of subdirectories
f2fs: Avoid reading renamed directory if parent does not change
ext4: don't access the source subdirectory content on same-directory rename
ext2: Avoid reading renamed directory if parent does not change
udf_rename(): only access the child content on cross-directory rename
ocfs2: Avoid touching renamed directory if parent does not change
reiserfs: Avoid touching renamed directory if parent does not change
The bulk of the patches for this release are clean-ups and minor bug
fixes.
There is one significant revert to mention: support for RDMA Read
operations in the server's RPC-over-RDMA transport implementation
has been fixed so it waits for Read completion in a way that avoids
tying up an nfsd thread. This prevents a possible DoS vector if an
RPC-over-RDMA client should become unresponsive during RDMA Read
operations.
As always I am grateful to NFSD contributors, reviewers, and
testers.
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Merge tag 'nfsd-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull nfsd updates from Chuck Lever:
"The bulk of the patches for this release are clean-ups and minor bug
fixes.
There is one significant revert to mention: support for RDMA Read
operations in the server's RPC-over-RDMA transport implementation has
been fixed so it waits for Read completion in a way that avoids tying
up an nfsd thread. This prevents a possible DoS vector if an
RPC-over-RDMA client should become unresponsive during RDMA Read
operations.
As always I am grateful to NFSD contributors, reviewers, and testers"
* tag 'nfsd-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (56 commits)
nfsd: rename nfsd_last_thread() to nfsd_destroy_serv()
SUNRPC: discard sv_refcnt, and svc_get/svc_put
svc: don't hold reference for poolstats, only mutex.
SUNRPC: remove printk when back channel request not found
svcrdma: Implement multi-stage Read completion again
svcrdma: Copy construction of svc_rqst::rq_arg to rdma_read_complete()
svcrdma: Add back svcxprt_rdma::sc_read_complete_q
svcrdma: Add back svc_rdma_recv_ctxt::rc_pages
svcrdma: Clean up comment in svc_rdma_accept()
svcrdma: Remove queue-shortening warnings
svcrdma: Remove pointer addresses shown in dprintk()
svcrdma: Optimize svc_rdma_cc_init()
svcrdma: De-duplicate completion ID initialization helpers
svcrdma: Move the svc_rdma_cc_init() call
svcrdma: Remove struct svc_rdma_read_info
svcrdma: Update the synopsis of svc_rdma_read_special()
svcrdma: Update the synopsis of svc_rdma_read_call_chunk()
svcrdma: Update synopsis of svc_rdma_read_multiple_chunks()
svcrdma: Update synopsis of svc_rdma_copy_inline_range()
svcrdma: Update the synopsis of svc_rdma_read_data_item()
...
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Merge tag 'vfs-6.8.rw' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs rw updates from Christian Brauner:
"This contains updates from Amir for read-write backing file helpers
for stacking filesystems such as overlayfs:
- Fanotify is currently in the process of introducing pre content
events. Roughly, a new permission event will be added indicating
that it is safe to write to the file being accessed. These events
are used by hierarchical storage managers to e.g., fill the content
of files on first access.
During that work we noticed that our current permission checking is
inconsistent in rw_verify_area() and remap_verify_area().
Especially in the splice code permission checking is done multiple
times. For example, one time for the whole range and then again for
partial ranges inside the iterator.
In addition, we mostly do permission checking before we call
file_start_write() except for a few places where we call it after.
For pre-content events we need such permission checking to be done
before file_start_write(). So this is a nice reason to clean this
all up.
After this series, all permission checking is done before
file_start_write().
As part of this cleanup we also massaged the splice code a bit. We
got rid of a few helpers because we are alredy drowning in special
read-write helpers. We also cleaned up the return types for splice
helpers.
- Introduce generic read-write helpers for backing files. This lifts
some overlayfs code to common code so it can be used by the FUSE
passthrough work coming in over the next cycles. Make Amir and
Miklos the maintainers for this new subsystem of the vfs"
* tag 'vfs-6.8.rw' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (30 commits)
fs: fix __sb_write_started() kerneldoc formatting
fs: factor out backing_file_mmap() helper
fs: factor out backing_file_splice_{read,write}() helpers
fs: factor out backing_file_{read,write}_iter() helpers
fs: prepare for stackable filesystems backing file helpers
fsnotify: optionally pass access range in file permission hooks
fsnotify: assert that file_start_write() is not held in permission hooks
fsnotify: split fsnotify_perm() into two hooks
fs: use splice_copy_file_range() inline helper
splice: return type ssize_t from all helpers
fs: use do_splice_direct() for nfsd/ksmbd server-side-copy
fs: move file_start_write() into direct_splice_actor()
fs: fork splice_file_range() from do_splice_direct()
fs: create {sb,file}_write_not_started() helpers
fs: create file_write_started() helper
fs: create __sb_write_started() helper
fs: move kiocb_start_write() into vfs_iocb_iter_write()
fs: move permission hook out of do_iter_read()
fs: move permission hook out of do_iter_write()
fs: move file_start_write() into vfs_iter_write()
...
RQ_SPLICE_OK is a bit of a layering violation. Also, a subsequent
patch is going to provide a mechanism for always disabling splice
reads.
Splicing is an issue only for NFS READs, so refactor nfsd_read() to
check the auth type directly instead of relying on an rq_flag
setting.
The new helper will be added into the NFSv4 read path in a
subsequent patch.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Al Viro notes that normal system calls hold f_pos_lock when calling
->iterate_shared and ->llseek; however nfsd_readdir() does not take
that mutex when calling these methods.
It should be safe however because the struct file acquired by
nfsd_readdir() is not visible to other threads.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This code is rarely (never?) enabled by distros, and it hasn't caught
anything in decades. Let's kill off this legacy debug code.
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
... and fix the directory locking documentation and proof of correctness.
Holding ->s_vfs_rename_mutex *almost* prevents ->d_parent changes; the
case where we really don't want it is splicing the root of disconnected
tree to somewhere.
In other words, ->s_vfs_rename_mutex is sufficient to stabilize "X is an
ancestor of Y" only if X and Y are already in the same tree. Otherwise
it can go from false to true, and one can construct a deadlock on that.
Make lock_two_directories() report an error in such case and update the
callers of lock_rename()/lock_rename_child() to handle such errors.
And yes, such conditions are not impossible to create ;-/
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
