kernel/linux.git/fs/nfs/export.c, branch v6.19.11

NFS: Fix filehandle bounds checking in nfs_fh_to_dentry()

2025-07-22T13:50:56+00:00

The function needs to check the minimal filehandle length before it can access the embedded filehandle. Reported-by: zhangjian Fixes: 20fa19027286 ("nfs: add export operations") Signed-off-by: Trond Myklebust

nfsd: disallow file locking and delegations for NFSv4 reexport

2025-03-10T13:11:08+00:00

We do not and cannot support file locking with NFS reexport over NFSv4.x for the same reason we don't do it for NFSv3: NFS reexport server reboot cannot allow clients to recover locks because the source NFS server has not rebooted, and so it is not in grace. Since the source NFS server is not in grace, it cannot offer any guarantees that the file won't have been changed between the locks getting lost and any attempt to recover/reclaim them. The same applies to delegations and any associated locks, so disallow them too. Clients are no longer allowed to get file locks or delegations from a reexport server, any attempts will fail with operation not supported. Update the "Reboot recovery" section accordingly in Documentation/filesystems/nfs/reexport.rst Signed-off-by: Mike Snitzer Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever

nfsd: allow reaping files still under writeback

2023-04-26T13:04:59+00:00

On most filesystems, there is no reason to delay reaping an nfsd_file just because its underlying inode is still under writeback. nfsd just relies on client activity or the local flusher threads to do writeback. The main exception is NFS, which flushes all of its dirty data on last close. Add a new EXPORT_OP_FLUSH_ON_CLOSE flag to allow filesystems to signal that they do this, and only skip closing files under writeback on such filesystems. Also, remove a redundant NULL file pointer check in nfsd_file_check_writeback, and clean up nfs's export op flag definitions. Signed-off-by: Jeff Layton Acked-by: Anna Schumaker Signed-off-by: Chuck Lever

Merge tag 'nfsd-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2023-02-22T22:21:40+00:00

Pull nfsd updates from Chuck Lever: "Two significant security enhancements are part of this release: - NFSD's RPC header encoding and decoding, including RPCSEC GSS and gssproxy header parsing, has been overhauled to make it more memory-safe. - Support for Kerberos AES-SHA2-based encryption types has been added for both the NFS client and server. This provides a clean path for deprecating and removing insecure encryption types based on DES and SHA-1. AES-SHA2 is also FIPS-140 compliant, so that NFS with Kerberos may now be used on systems with fips enabled. In addition to these, NFSD is now able to handle crossing into an auto-mounted mount point on an exported NFS mount. A number of fixes have been made to NFSD's server-side copy implementation. RPC metrics have been converted to per-CPU variables. This helps reduce unnecessary cross-CPU and cross-node memory bus traffic, and significantly reduces noise when KCSAN is enabled" * tag 'nfsd-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (121 commits) NFSD: Clean up nfsd_symlink() NFSD: copy the whole verifier in nfsd_copy_write_verifier nfsd: don't fsync nfsd_files on last close SUNRPC: Fix occasional warning when destroying gss_krb5_enctypes nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_open NFSD: fix problems with cleanup on errors in nfsd4_copy nfsd: fix race to check ls_layouts nfsd: don't hand out delegation on setuid files being opened for write SUNRPC: Remove ->xpo_secure_port() SUNRPC: Clean up the svc_xprt_flags() macro nfsd: remove fs/nfsd/fault_inject.c NFSD: fix leaked reference count of nfsd4_ssc_umount_item nfsd: clean up potential nfsd_file refcount leaks in COPY codepath nfsd: zero out pointers after putting nfsd_files on COPY setup error SUNRPC: Fix whitespace damage in svcauth_unix.c nfsd: eliminate __nfs4_get_fd nfsd: add some kerneldoc comments for stateid preprocessing functions nfsd: eliminate find_deleg_file_locked nfsd: don't take nfsd4_copy ref for OP_OFFLOAD_STATUS SUNRPC: Add encryption self-tests ...

NFS: nfs_encode_fh: Remove S_AUTOMOUNT check

2023-02-20T14:20:09+00:00

Now with NFSD being able to cross into auto mounts, the check can be removed. Signed-off-by: Richard Weinberger Reviewed-by: Ian Kent Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Acked-by: Anna Schumaker

nfsd: remove fetch_iversion export operation

2023-01-26T12:00:06+00:00

Now that the i_version counter is reported in struct kstat, there is no need for this export operation. Acked-by: Chuck Lever Reviewed-by: NeilBrown Signed-off-by: Jeff Layton

nfs: block notification on fs with its own ->lock

2022-01-08T19:42:01+00:00

NFSv4.1 supports an optional lock notification feature which notifies the client when a lock comes available. (Normally NFSv4 clients just poll for locks if necessary.) To make that work, we need to request a blocking lock from the filesystem. We turned that off for NFS in commit f657f8eef3ff ("nfs: don't atempt blocking locks on nfs reexports") [sic] because it actually blocks the nfsd thread while waiting for the lock. Thanks to Vasily Averin for pointing out that NFS isn't the only filesystem with that problem. Any filesystem that leaves ->lock NULL will use posix_lock_file(), which does the right thing. Simplest is just to assume that any filesystem that defines its own ->lock is not safe to request a blocking lock from. So, this patch mostly reverts commit f657f8eef3ff ("nfs: don't atempt blocking locks on nfs reexports") [sic] and commit b840be2f00c0 ("lockd: don't attempt blocking locks on nfs reexports"), and instead uses a check of ->lock (Vasily's suggestion) to decide whether to support blocking lock notifications on a given filesystem. Also add a little documentation. Perhaps someday we could add back an export flag later to allow filesystems with "good" ->lock methods to support blocking lock notifications. Reported-by: Vasily Averin Signed-off-by: J. Bruce Fields [ cel: Description rewritten to address checkpatch nits ] [ cel: Fixed warning when SUNRPC debugging is disabled ] [ cel: Fixed NULL check ] Signed-off-by: Chuck Lever Reviewed-by: Vasily Averin

NFS: Remove the nfs4_label argument from nfs_fhget()

2021-11-05T18:54:40+00:00

Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust

NFS: Remove the nfs4_label from the nfs4_getattr_res

2021-11-05T18:54:39+00:00

Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust

NFS: Remove the nfs4_label from the nfs4_lookupp_res struct

2021-11-05T18:54:39+00:00

Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust