kernel/linux.git/fs/nfsd, branch v7.1.2

Revert "NFSD: Defer sub-object cleanup in export put callbacks"

2026-06-27T10:08:17+00:00

commit 516403d4d85607fdef3ca41d4a56b54e5566fa9a upstream. This reverts commit 48db892356d6cb80f6942885545de4a6dd8d2a29. Commit 48db892356d6 ("NFSD: Defer sub-object cleanup in export put callbacks") moved path_put() and auth_domain_put() out of svc_export_put() and expkey_put() and behind queue_rcu_work() to close a claimed use-after-free in e_show() and c_show() against ex_path and ex_client->name. Discussion in [1] shows neither the diagnosis nor the remedy survives review. The downstream teardown of both sub-objects is already RCU-deferred. auth_domain_put() reaches svcauth_unix_domain_release(), which frees the unix_domain and its ->name through call_rcu(). path_put() reaches dentry_free(), which frees the dentry through call_rcu(), and prepend_path() is already structured to tolerate concurrent dentry teardown. A reader in cache_seq_start_rcu() therefore observes both sub-objects through the next grace period regardless of whether svc_export_put() runs synchronously, so the synchronous form was never unsafe. The crash signature in the report cited by commit 48db892356d6 ("NFSD: Defer sub-object cleanup in export put callbacks") has a different root cause: a /proc/net/rpc cache file held open across network-namespace exit lets cache_destroy_net() free cd->hash_table while a reader is still walking it. The correct fix pins cd->net for the open fd's lifetime and does not require any deferral inside svc_export_put(). Meanwhile, deferring path_put() out of svc_export_put() reintroduces the regression that commit 69d803c40ede ("nfsd: Revert "nfsd: release svc_expkey/svc_export with rcu_work"") repaired: after "exportfs -r" drops the last cache reference, the mount reference held through ex_path lingers in the workqueue, so a subsequent umount fails with EBUSY. Restore the synchronous path_put() and auth_domain_put() in svc_export_put() and expkey_put() and the call_rcu()/kfree_rcu() free of the containing structures. The unrelated fix for ex_uuid/ex_stats from commit 2530766492ec ("nfsd: fix UAF when access ex_uuid or ex_stats") is preserved. Link: https://lore.kernel.org/all/10019b42-4589-4f9f-8d5b-d8197db1ce3c@huawei.com/ [1] Fixes: 48db892356d6 ("NFSD: Defer sub-object cleanup in export put callbacks") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton Tested-by: Alexandr Alexandrov Signed-off-by: Yang Erkun Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman

Merge tag 'nfsd-7.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2026-05-26T20:49:13+00:00

Pull nfsd fixes from Chuck Lever: "Regressions: - Tighten bounds checking for sunrpc cache hash tables - Don't report key material in the ftrace log Stable fix: - Fix lockd's implementation of the NLM TEST procedure" * tag 'nfsd-7.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: lockd: fix TEST handling when not all permissions are available. NFSD: Report whether fh_key was actually updated sunrpc: prevent out-of-bounds read in __cache_seq_start()

NFSD: Report whether fh_key was actually updated

2026-05-21T21:08:47+00:00

The nfsd_ctl_fh_key_set tracepoint was introduced to capture operator activity on the filehandle signing key. Earlier revisions logged the key bytes verbatim; the version that landed hashes the 16 key bytes through crc32_le and stores the result. CRC32 is a linear projection of its input rather than a one-way function, and truncating any hash of fixed-size secret material leaves the key recoverable under offline brute force when the threat model includes an attacker with access to the trace ring. The operational question the fingerprint was meant to answer is whether a NFSD_CMD_THREADS_SET call that carries an NFSD_A_SERVER_FH_KEY attribute actually replaced the active key or re-installed the value already in place. Answer that question directly: compare the incoming key bytes against the current nn->fh_key inside nfsd_nl_fh_key_set() and surface a single bit to the tracepoint. The event now prints "updated" when the stored key changed and "unmodified" otherwise. A first set that fails kmalloc reports "unmodified" because no key was installed. Reported-by: jaeyeong Fixes: 62346217fd72 ("NFSD: Add a key for signing filehandles") Cc: Benjamin Coddington Reviewed-by: Benjamin Coddington Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever

Merge tag 'nfsd-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2026-05-15T20:11:41+00:00

Pull nfsd fixes from Chuck Lever: "Fixes for this release: - Correctness fix for the new sunrpc cache netlink protocol Marked for stable: - Correctness fixes for delegated attributes - Prevent an infinite loop when revoking layouts" * tag 'nfsd-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: NFSD: Fix infinite loop in layout state revocation sunrpc: start cache request seqno at 1 to fix netlink GET_REQS nfsd: update mtime/ctime on COPY in presence of delegated attributes nfsd: update mtime/ctime on CLONE in presense of delegated attributes nfsd: fix file change detection in CB_GETATTR nfsd: fix GET_DIR_DELEGATION when VFS leases are disabled

NFSD: Fix infinite loop in layout state revocation

2026-05-10T16:41:08+00:00

find_one_sb_stid() skips stids whose sc_status is non-zero, but the SC_TYPE_LAYOUT case in nfsd4_revoke_states() never sets sc_status before calling nfsd4_close_layout(). The retry loop therefore finds the same layout stid on every iteration, hanging the revoker indefinitely. Fixes: 1e33e1414bec ("nfsd: allow layout state to be admin-revoked.") Reported-by: Dai Ngo Reviewed-by: Jeff Layton Tested-by: Dai Ngo Signed-off-by: Chuck Lever

nfsd: update mtime/ctime on COPY in presence of delegated attributes

2026-05-10T16:41:03+00:00

When delegated attributes are given on open, the file is opened with NOCMTIME and modifying operations do not update mtime/ctime as to not get out-of-sync with the client's delegated view. However, for COPY operation, the server should update its view of mtime/ctime and reflect that in any GETATTR queries. Fixes: e5e9b24ab8fa ("nfsd: freeze c/mtime updates with outstanding WRITE_ATTRS delegation") Cc: stable@vger.kernel.org Signed-off-by: Olga Kornievskaia Signed-off-by: Chuck Lever

nfsd: update mtime/ctime on CLONE in presense of delegated attributes

2026-05-10T16:39:48+00:00

When delegated attributes are given on open, the file is opened with NOCMTIME and modifying operations do not update mtime/ctime as to not get out-of-sync with the client's delegated view. However, for CLONE operation, the server should update its view of mtime/ctime and reflect that in any GETATTR queries. Fixes: e5e9b24ab8fa ("nfsd: freeze c/mtime updates with outstanding WRITE_ATTRS delegation") Cc: stable@vger.kernel.org Signed-off-by: Olga Kornievskaia Signed-off-by: Chuck Lever

nfsd: fix file change detection in CB_GETATTR

2026-05-10T16:32:26+00:00

RFC 8881, section 10.4.3 doesn't say anything about caching the file size in the delegation record, nor does it say anything about comparing a cached file size with the size reported by the client in the CB_GETATTR reply for the purpose of determining if the client holds modified data for the file. What section 10.4.3 of RFC 8881 does say is that the server should compare the *current* file size with the size reported by the client holding the delegation in the CB_GETATTR reply, and if they differ to treat it as a modification regardless of the change attribute retrieved via the CB_GETATTR. Doing otherwise would cause the server to believe the client holding the delegation has a modified version of the file, even if the client flushed the modifications to the server prior to the CB_GETATTR. This would have the added side effect of subsequent CB_GETATTRs causing updates to the mtime, ctime, and change attribute even if the client holding the delegation makes no further updates to the file. Modify nfsd4_deleg_getattr_conflict() to obtain the current file size via i_size_read(). Retain the ncf_cur_fsize field, since it's a convenient way to return the file size back to nfsd4_encode_fattr4(), but don't use it for the purpose of detecting file changes. Remove the unnecessary initialization of ncf_cur_fsize in nfs4_open_delegation(). Also, if we recall the delegation (because the client didn't respond to the CB_GETATTR), then skip the logic that checks the nfs4_cb_fattr fields. Fixes: c5967721e106 ("NFSD: handle GETATTR conflict with write delegation") Cc: stable@vger.kernel.org Signed-off-by: Scott Mayhew Signed-off-by: Chuck Lever

nfsd: fix GET_DIR_DELEGATION when VFS leases are disabled

2026-04-27T01:05:49+00:00

When leases are disabled on the server, running xfstest generic/309 leads to an error because GET_DIR_DELEGATION returns EINVAL. nfsd_get_dir_deleg() can fail in several ways: like memory allocation and unable to get a lease because either leases are disable or it's already held. Currently only the condition "already held" is translated to returning directory-delegation-is-unavailable error. However, other failure conditions are likely temporary and thus should result in the same kind of error. Fixes: 8b99f6a8c116 ("nfsd: wire up GET_DIR_DELEGATION handling") Cc: stable@vger.kernel.org Signed-off-by: Olga Kornievskaia Signed-off-by: Chuck Lever

Merge tag 'nfsd-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2026-04-20T17:44:02+00:00

Pull nfsd updates from Chuck Lever: - filehandle signing to defend against filehandle-guessing attacks (Benjamin Coddington) The server now appends a SipHash-2-4 MAC to each filehandle when the new "sign_fh" export option is enabled. NFSD then verifies filehandles received from clients against the expected MAC; mismatches return NFS error STALE - convert the entire NLMv4 server-side XDR layer from hand-written C to xdrgen-generated code, spanning roughly thirty patches (Chuck Lever) XDR functions are generally boilerplate code and are easy to get wrong. The goals of this conversion are improved memory safety, lower maintenance burden, and groundwork for eventual Rust code generation for these functions. - improve pNFS block/SCSI layout robustness with two related changes (Dai Ngo) SCSI persistent reservation fencing is now tracked per client and per device via an xarray, to avoid both redundant preempt operations on devices already fenced and a potential NFSD deadlock when all nfsd threads are waiting for a layout return. - scalability and infrastructure improvements Sincere thanks to all contributors, reviewers, testers, and bug reporters who participated in the v7.1 NFSD development cycle. * tag 'nfsd-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (83 commits) NFSD: Docs: clean up pnfs server timeout docs nfsd: fix comment typo in nfsxdr nfsd: fix comment typo in nfs3xdr NFSD: convert callback RPC program to per-net namespace NFSD: use per-operation statidx for callback procedures svcrdma: Use contiguous pages for RDMA Read sink buffers SUNRPC: Add svc_rqst_page_release() helper SUNRPC: xdr.h: fix all kernel-doc warnings svcrdma: Factor out WR chain linking into helper svcrdma: Add Write chunk WRs to the RPC's Send WR chain svcrdma: Clean up use of rdma->sc_pd->device svcrdma: Clean up use of rdma->sc_pd->device in Receive paths svcrdma: Add fair queuing for Send Queue access SUNRPC: Optimize rq_respages allocation in svc_alloc_arg SUNRPC: Track consumed rq_pages entries svcrdma: preserve rq_next_page in svc_rdma_save_io_pages SUNRPC: Handle NULL entries in svc_rqst_release_pages SUNRPC: Allocate a separate Reply page array SUNRPC: Tighten bounds checking in svc_rqst_replace_page NFSD: Sign filehandles ...