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3 daystreewide: refresh kmalloc_obj() conversionsKees Cook
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-08-10nfsd: export NFSv4 callback op stats via netlinkJeff Layton
Add a proc4cb-ops nested attribute to the server-stats netlink dump, reusing the existing server-proc-entry (op/count) layout. The dump gains a callback section that emits one entry per callback opcode (OP_CB_GETATTR..OP_CB_OFFLOAD) from the per-netns callback counters, paged across messages like the other per-operation sections. This lets nfsstat report NFSv4 backchannel operation counts over netlink, including CB_GETATTR which corresponds to the procfs wdeleg_getattr line. Assisted-by: LLM Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260717-exportd-netlink-v7-6-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: count NFSv4 callback operations per netnsJeff Layton
The NFS server tracks per-operation call counts for the forward channel (proc4ops) but keeps no statistics for the NFSv4 backchannel (callback) operations it sends to clients. Add a per-netns array of percpu counters for callback operations, indexed by RFC 8881 callback opcode (OP_CB_GETATTR..OP_CB_OFFLOAD), and bump the relevant counter in nfsd4_run_cb(), which is hit exactly once per callback that is actually queued. CB_GETATTR is sent when a GETATTR conflicts with an outstanding write delegation, which is roughly what the dedicated wdeleg_getattr counter tracked. The two are not identical: the old counter incremented on every such conflict, whereas the CB_GETATTR counter only counts callbacks that are actually queued, so concurrent conflicts that coalesce onto an already in-flight CB_GETATTR are now counted once rather than once per conflict. Report the procfs "wdeleg_getattr" line from the CB_GETATTR counter and drop the now-redundant NFSD_STATS_WDELEG_GETATTR counter, its helper, and its increment site. Assisted-by: LLM Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260717-exportd-netlink-v7-5-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: remove unused svc_version vs_count fieldJeff Layton
Now that svc_seq_show() and the nfsd netlink stats handler both use the per-netns svc_stat vs_count arrays, the global per-version vs_count percpu counters are no longer read by anything. Remove the vs_count field from struct svc_version and all the associated DEFINE_PER_CPU_ALIGNED arrays and initializers across nfsd, lockd, and the NFS client callback service. Assisted-by: LLM Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260717-exportd-netlink-v7-4-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: implement server-stats-get netlink handlerJeff Layton
Implement nfsd_nl_server_stats_get_dumpit() which exposes the NFS server statistics currently available via /proc/net/rpc/nfsd through the nfsd generic netlink family. The handler uses a dump operation to stream statistics across one or more netlink messages. The reply is divided into sections that are emitted in order: - scalar stats (reply cache, filehandle, IO, network, RPC), emitted once in the first message, then - per-version procedure counts (proc2/3/4-ops) and the NFSv4 per-operation counts (proc4ops-ops), using the per-netns vs_count arrays. cb->args[0] tracks the current section and cb->args[1] the entry index within it, so a section that does not fit in the current message is closed and resumed in the next one. This matters because the first dump message is allocated at NLMSG_GOODSIZE (a single page on most architectures) regardless of the client's receive buffer; packing every counter into one message would overflow it and fail the dump with -EMSGSIZE. Userspace merges the attributes from every message. This allows nfsstat to retrieve server statistics via netlink with a procfs fallback for older kernels. Assisted-by: LLM Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260717-exportd-netlink-v7-3-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: add per-netns per-procedure call counts to svc_statJeff Layton
The existing per-procedure call counts live in global svc_version->vs_count[] arrays which are not network-namespace-aware. Add per-netns equivalents in struct svc_stat so the upcoming netlink stats interface can return namespace-scoped statistics. Add a vs_count pointer array to struct svc_stat, along with svc_stat_alloc_counts() and svc_stat_free_counts() helpers to manage per-version percpu call count arrays. Increment the per-net counter alongside the global one in svc_generic_init_request(). Call the alloc/free helpers from nfsd_net_init() and nfsd_net_exit(). Assisted-by: LLM Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260717-exportd-netlink-v7-1-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Eliminate percpu counter contention in IO byte accountingChuck Lever
nfsd_stats_io_write_add() and nfsd_stats_io_read_add() accumulate byte counts in per-net-namespace and per-export percpu_counters using percpu_counter_add(), which applies the default batch threshold of max(32, 2*nr_cpus). For a 4 KB NFS WRITE, the amount (4096) always exceeds this threshold, so percpu_counter_add_batch() acquires the counter's global spinlock on every update. Each WRITE RPC updates two counters (per-net and per-export), producing two global lock acquisitions per operation. Profiling on a 10-CPU RDMA NFS server shows 0.44% of total CPU cycles spent contending on these locks during a small random write workload. Switch to percpu_counter_add_local(), which batches with INT_MAX so that updates always remain on the per-CPU fast path regardless of the amount. All readers of these counters already use percpu_counter_sum_positive(), which sums the per-CPU deltas under the global lock, so read accuracy is unaffected. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260717001232.438792-5-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Eliminate percpu counter contention in reply cache statisticsChuck Lever
Each RPC passes through nfsd_cache_lookup(), which increments one of nfsd_stats_rc_hits_inc(), nfsd_stats_rc_misses_inc(), or nfsd_stats_rc_nocache_inc(). These helpers update per-net-namespace percpu_counters with percpu_counter_inc(), which applies the default batch threshold of max(32, 2*nr_cpus). Once a CPU's local delta reaches that threshold, the update folds into the shared counter under its global spinlock. On a busy multi-CPU server this produces lock traffic on a counter cacheline shared across all CPUs, growing with the request rate. Switch to percpu_counter_add_local(fbc, 1), which batches with INT_MAX so that increments always remain on the per-CPU fast path. This matches the treatment already applied to the IO byte and DRC memory counters. All readers of these counters use percpu_counter_sum_positive(), which sums the per-CPU deltas under the global lock, so read accuracy is unaffected. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260717001232.438792-4-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Eliminate percpu counter contention in DRC memory accountingChuck Lever
The DRC memory usage counter (NFSD_STATS_DRC_MEM_USAGE) tracks bytes, but percpu_counter_add() uses the global percpu_counter_batch threshold of max(32, 2*nr_cpus). Each DRC entry add or removal updates the counter by sizeof(struct nfsd_cacherep) (~144 bytes), which always exceeds the batch threshold. percpu_counter_add() then acquires the counter's global spinlock on every update, serializing all nfsd threads. On a 10-CPU NFS server handling a high rate of non-idempotent NFSv3 operations, this lock accounts for a measurable fraction of total spin lock overhead because nfsd_cache_lookup() both inserts a new entry and prunes up to three old entries per RPC, producing 4-7 global lock acquisitions per operation. Switch to percpu_counter_add_local() and percpu_counter_sub_local(), which batch with INT_MAX so that updates always remain on the per-CPU fast path regardless of the amount. The only reader of this counter uses percpu_counter_sum_positive(), which sums the per-CPU deltas under the global lock, so read accuracy is unaffected. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260717001232.438792-3-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Fix off-by-one in DRC bucket pruning limitChuck Lever
nfsd_prune_bucket_locked() evicts an entry before checking the freed count against @max. The check uses "++freed > max", which does not break until freed exceeds max, resulting in max + 1 evictions. Use ">=" so the limit stated in the function comment is honored. Fixes: a9507f6af145 ("NFSD: Replace nfsd_prune_bucket()") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260717001232.438792-2-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Relocate NFSv4 "supported attributes" to new headerChuck Lever
These NFSv4 attribute bitmask definitions live in nfsd.h, which nearly every nfsd source file includes, yet only nfs4proc.c and nfs4xdr.c reference them. Move them to a dedicated header so only those two consumers pull them in. While moving the block, correct the stale QUOTA_* annotation: the promised support never materialized, so these attributes are unlikely to be supported any time soon rather than forthcoming. Link: https://patch.msgid.link/20260712204554.125308-10-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Relocate nfsd4_set_netaddr()Chuck Lever
Clean up: Common practice in the Linux kernel is to avoid the use of static inline functions when there is only a single call site. The 30-line helper function is removed from a header pulled into ~25 .c files, removing <linux/sunrpc/addr.h> from that header's transitive include surface, dropping a now-redundant <linux/sunrpc/msg_prot.h> include, and reducing the function's visibility to the one translation unit that uses it. Link: https://patch.msgid.link/20260712204554.125308-9-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Relocate nfsd_user_namespace()Chuck Lever
Refactor: nfsd_user_namespace() currently lives in nfsd.h, so every caller must pull in nfsd.h -- directly or transitively via state.h -- and with it the NFS protocol definitions from uapi/linux/nfs.h and friends, even when the caller uses nothing else from nfsd.h. Since nfsd_user_namespace() is an auth-related function, move it to fs/nfsd/auth.c in preparation for removing '#include "nfsd.h"' from a few places. Link: https://patch.msgid.link/20260712204554.125308-8-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Move struct readdir_cdChuck Lever
struct readdir_cd is part of the VFS readdir API, but it lives in nfsd.h, the subsystem's catch-all header, rather than alongside that API. That forces vfs.h to include nfsd.h solely to declare readdir_cd for its nfsd_readdir() prototype, a layering inversion since vfs.h is the lower-level shim. Relocate readdir_cd to vfs.h, just below the nfsd_filldir_t callback typedef. vfs.h then defines the struct itself and no longer includes nfsd.h. The xdr headers that embed readdir_cd by value include vfs.h to obtain the definition. This prepares the ground for dropping nfsd.h from more files. Link: https://patch.msgid.link/20260712204554.125308-7-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Move the export.h include from nfsd.h to auth.cChuck Lever
Nothing declared in fs/nfsd/nfsd.h references a type, macro, or function that export.h defines. The include is present only so that source files including nfsd.h pick up export.h's definitions transitively. Of the twenty source files that include nfsd.h, only auth.c relies on that side effect: it names struct svc_export and the NFSEXP_* flags yet includes no header that supplies them. Add the export.h include directly to auth.c, then drop it from nfsd.h so the header carries only the dependencies its own declarations require. Link: https://patch.msgid.link/20260712204554.125308-6-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Remove '#include "nfsd.h"' from fs/nfsd/cache.hChuck Lever
Clean up: cache.h does not need the full definition of struct nfsd_net. A forward declaration suffices. Link: https://patch.msgid.link/20260712204554.125308-5-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: include "netns.h"Chuck Lever
Nothing in fs/nfsd/nfsd.h needs the contents of "netns.h"; the prototypes there that take a struct nfsd_net pointer need only a forward declaration of that type. Relocate the existing forward declaration ahead of the first such prototype, drop the "netns.h" include from nfsd.h, and include it directly in the translation units that operate on struct nfsd_net. "netns.h" had also been the path by which <linux/filelock.h> reached nfsxdr.c and state.h. Both now include <linux/filelock.h> themselves. Link: https://patch.msgid.link/20260712204554.125308-4-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Explicitly include "stats.h"Chuck Lever
Nothing in fs/nfsd/nfsd.h needs what is defined in "stats.h", so that header can be moved out to the six translation units that actually need it. Link: https://patch.msgid.link/20260712204554.125308-3-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Make "stats.h" self-containedChuck Lever
The inline helpers in fs/nfsd/stats.h dereference struct nfsd_net and struct svc_export, yet the header includes neither "netns.h" nor "export.h", where those types are defined. Each helper therefore compiles only when its translation unit has already pulled in both headers ahead of "stats.h" -- a hidden ordering requirement that has to be honored at every include site. Include "netns.h" and "export.h" from "stats.h" directly so the header stands on its own, and no consumer has to order its includes to satisfy it. Link: https://patch.msgid.link/20260712204554.125308-2-cel@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10xdrgen: Emit a blank line ahead of enum declarationsChuck Lever
Clean up. The declaration templates for structs, pointers, and typedefs each begin with a blank line, which keeps successive declarations and the include block above them visually separated. The enum declaration template omits that blank line. trim_blocks collapses the template's lone comment line to nothing, so the omission stayed invisible as long as every generated header happened to lead with a non-enum declaration. Fixes: 4329010ad9c3 ("xdrgen: Address some checkpatch whitespace complaints") Link: https://patch.msgid.link/20260712193122.116845-2-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Encode only the status in NFS-ACL v2 GETACL error repliesChuck Lever
The NFSv2 ACL GETACL reply is a union that carries file attributes and ACL data only when the status is NFS_OK. All error cases are void results. However, currently the NFSv2 ACL GETACL result encoder decides whether to append the "OK" body by testing only whether the file handle resolved to a positive dentry, not the actual reply status. A GETACL request that resolves its file handle but then fails for another reason (an unsupported mask value, a getattr failure, or an ACL retrieval error) therefore appends file attributes and ACL data after the error status on the wire. Worse, when the mask is rejected, fh_getattr() hasn't been called at all, so those attributes are serialized from a zero-filled kstat and are junk. The logic before the xdr_stream conversion used the reply status. Revert to that approach (but keep the xdr_stream conversion in place). Fixes: f8cba47344f7 ("NFSD: Update the NFSv2 GETACL result encoder to use struct xdr_stream") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260712150911.48461-1-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: drop dead COPY-vs-COPYNOTIFY type handling from s2s stateid IDRJeff Layton
Now that the COPY offload stateid is a first-class nfs4_stid, nn->s2s_cp_stateids holds COPY_NOTIFY stateids exclusively (its only inserter, nfs4_init_cp_state(), runs only from nfs4_alloc_init_cpntf_state()). The type-distinguishing machinery is dead: - remove the unreferenced NFS4_COPY_STID definition; - drop nfs4_init_cp_state()'s cs_type argument (hardcode NFS4_COPYNOTIFY_STID) and its now-always-true "if (p_stid)" guard; - remove the cs_type == NFS4_COPYNOTIFY_STID gates in manage_cpntf_state() and the laundromat, which can no longer be false. copy_stateid_t.cs_type is retained for the WARN_ON_ONCE() sanity checks on the free paths. No functional change. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-10-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: make the copy offload stateid a first-class nfs4_stidJeff Layton
The async COPY offload stateid was a copy_stateid_t in the per-net nn->s2s_cp_stateids IDR, sharing that table with COPY_NOTIFY stateids even though every reader (laundromat, manage_cpntf_state()) accepts only NFS4_COPYNOTIFY_STID. It was inserted there only to mint a unique so_id; OFFLOAD_CANCEL and OFFLOAD_STATUS find the copy by walking clp->async_copies. Building on the nfsd4_async_copy split, promote it to a first-class nfs4_stid (SC_TYPE_COPY) embedded at the head of nfsd4_async_copy and allocated from the client's cl_stateids via nfs4_alloc_stid(). This: - makes the stateid per-client by construction rather than relying on a guessable cyclic id in a global table; - reuses the common id allocation, refcounting, and teardown (nfs4_put_stid() + sc_free), removing the bespoke nfs4_init_copy_state()/nfs4_free_copy_state(); and - leaves nn->s2s_cp_stateids exclusively for COPY_NOTIFY stateids. The async-copy lifetime model is unchanged; nf4_put_copy() now drops the stid's single reference, which removes it from cl_stateids and frees the slab. Per RFC 7862 Section 4.8 a copy offload stateid is valid only for COPY/OFFLOAD_CANCEL/OFFLOAD_STATUS/CB_OFFLOAD, not FREE_STATEID or TEST_STATEID, so find_stateid_locked() hides SC_TYPE_COPY and those paths keep returning bad_stateid as before. Its seqid MUST NOT be zero, so set si_generation to 1 (nfs4_alloc_stid() leaves it zero). Follow-ups (not done here): NFS4_COPY_STID, the now-always-COPYNOTIFY branch in nfs4_init_cp_state(), and the redundant cs_type checks in the laundromat and manage_cpntf_state() are vestigial. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-9-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: split nfsd4_copy into transient and durable async copy objectsJeff Layton
struct nfsd4_copy served two roles: as &u->copy it is a transient per-COMPOUND argument in the request buffer; as the heap async_copy it is a durable object (worker kthread, reaper linkage, CB_OFFLOAD callback, IDR stateid) that outlives the COMPOUND, with dup_copy_fields() shuttling state between them. That dual identity was the root of the recent lifetime bugs. Introduce struct nfsd4_async_copy for the durable object. It embeds a struct nfsd4_copy (cp_copy) for the operation parameters/result and adds the durable-only fields: async_copies linkage, task_struct, refcount, reaper TTL, copy stateid, and CB_OFFLOAD callback. The durable object therefore never points into the request buffer. cp_clp stays in nfsd4_copy -- it is a request property read by the sync-copy tracepoints on the transient object. Mechanical split, no intended behavioral change; a step toward folding the copy stateids into the common nfs4_stid infrastructure. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-8-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: return NFS4ERR_NOTSUPP for unsupported netloc4 typesJeff Layton
nfsd4_decode_nl4_server() handled only NL4_NETADDR and returned nfserr_bad_xdr for NL4_NAME and NL4_URL. Those forms are well-formed XDR, so BADXDR is misleading -- the request is unsupported, not malformed. Decode and discard the utf8str_cis for NL4_NAME and NL4_URL to keep the stream consistent, and return nfserr_notsupp. nfsd4_proc_compound() honors a decode-time op->status, so the op fails without executing. Fixes: 84e1b21d5ec4 ("NFSD add ca_source_server<> to COPY") Cc: stable@vger.kernel.org Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-7-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: revoke copy-notify stateids before dropping their referenceJeff Layton
Copy-notify stateids live in the s2s_cp_stateids IDR and on their parent stid's sc_cp_list, pinned by a single membership reference. _free_cpntf_state_locked() only unlinks an entry once its refcount reaches zero, so any revoke path that runs while a concurrent find_cpntf_state()/manage_cpntf_state() holder has elevated cs_count drops the reference without unlinking, leaving the entry discoverable with its membership reference already consumed. A second revoke or a laundromat tick then frees it while the reader still holds the pointer -- a KASAN-detectable use-after-free at the reader's nfs4_put_cpntf_state(). This affected all three revoke paths: - The parent-stid drain (nfs4_free_cpntf_statelist()) repeatedly called _free_cpntf_state_locked() on the first list entry; a holder that had bumped cs_count made it return early, so the next iteration re-decremented and burned the holder's reference. - OFFLOAD_CANCEL (manage_cpntf_state()) and laundromat expiry likewise used _free_cpntf_state_locked() and could drop 2->1 without unlinking. Add revoke_cpntf_state_locked(), which unhashes the entry from the IDR and sc_cp_list first (deferring the final free to any holder), and use it from all three revoke paths. The drain now walks with list_for_each_entry_safe() and revokes each entry unconditionally, so it terminates in one pass per entry regardless of cs_count. The unhash is gated on !list_empty(&cps->cp_list); the idr_remove() gate matters because idr_alloc_cyclic() may have recycled the so_id by then. Keep _free_cpntf_state_locked() for the reference-holder put path only, where a concurrent revoke may already have unlinked the entry (its list_del_init() then a no-op). Fixes: 624322f1adc5 ("NFSD add COPY_NOTIFY operation") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-6-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: check client ownership when cancelling a copy-notify stateidJeff Layton
On the OFFLOAD_CANCEL path (clp != NULL), manage_cpntf_state() freed the target cpntf state without checking ownership. The lookup key st->si_opaque.so_id is allocated cyclically (guessable) and the embedded clientid is the fixed per-net nn->s2s_cp_cl_id, so any authenticated NFSv4.2 client could cancel and free another client's copy-notify stateid. Compare the creating clientid recorded in state->cp_p_clid against the requesting client's cl_clientid and return nfserr_bad_stateid on a mismatch instead of freeing the entry. Fixes: ce0887ac96d3 ("NFSD add nfs4 inter ssc to nfsd4_copy") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-5-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: initialize copy-notify stateid before publishing itJeff Layton
nfsd4_copy_notify() finished initializing the cpntf state after nfs4_alloc_init_cpntf_state() had already linked it into the s2s_cp_stateids IDR and the parent's sc_cp_list, with cs_count == 1 (the membership reference) and none held for the caller. A racing OFFLOAD_CANCEL (crafted cl_id == nn->s2s_cp_cl_id plus the guessable so_id) could reach manage_cpntf_state() and free the entry, turning the caller's subsequent cpn_cnr_stateid read and cp_p_stateid/cp_p_clid writes into use-after-free. The owning clientid was also only recorded after publication, so it could not gate an ownership check in that window. Record cp_p_stateid and cp_p_clid inside nfs4_alloc_init_cpntf_state() before nfs4_init_cp_state() publishes the entry, and return it with an extra reference. The caller reads the stateid under that reference and drops it with nfs4_put_cpntf_state(); on a late error the laundromat reaps the entry. Fixes: 624322f1adc5 ("NFSD add COPY_NOTIFY operation") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-4-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: fix stale s2s_cp_stateids IDR entry for async COPYJeff Layton
For an async COPY, nfsd4_copy() called nfs4_init_copy_state() before dup_copy_fields(), so the s2s_cp_stateids IDR was pointed at &u->copy->cp_stateid -- memory in the per-rqstp COMPOUND buffer that is reused by the next request. dup_copy_fields() copies only the value into async_copy, so the IDR slot dangled at the transient buffer for the whole background copy. Any IDR walker then dereferences reused request memory: the laundromat reads cs_type from it and, if the bytes look like an expired NFS4_COPYNOTIFY_STID, follows into refcount_dec()/idr_remove()/kfree() on garbage; manage_cpntf_state() has the same exposure via idr_find(). Duplicate the fields first, then register the stateid on the stable async_copy. result->cb_stateid is unchanged. Fixes: e0639dc5805a ("NFSD introduce async copy feature") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-3-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: fix UAF in async copy cancel and shutdownJeff Layton
An async copy could be freed or used after free while a teardown caller (OFFLOAD_CANCEL, nfsd4_shutdown_copy, nfsd4_cancel_copy_by_sb) raced the copy kthread: - find_async_copy() bumped copy->refcount but left the copy on clp->async_copies, so the reaper's cleanup_async_copy() could run release_copy_files() concurrently with a cancel/shutdown caller. Both put and NULL nf_src/nf_dst without a common lock, double-putting the nfsd_file and freeing it early. - nfsd4_do_async_copy() set NFSD4_COPY_F_STOPPED before its final uses of the copy (nfsd_update_cmtime_attr() on copy->nf_dst, nfsd4_send_cb_offload()). nfsd4_stop_copy() treats a set STOPPED bit as "kthread done, skip kthread_stop()", so a teardown caller ran release_copy_files() -- which puts and NULLs nf_dst -- while the kthread still dereferenced it (NULL/UAF). - copy->copy_task was never pinned. The one-shot kthread self-reaps on return, so kthread_stop()'s get_task_struct() could touch a freed task_struct. - co_cb is embedded in the copy, but nfsd4_send_cb_offload() held a reference only on the client, so a concurrent teardown could free the copy while the CB_OFFLOAD callback was in flight. Fix the teardown lifetime as a whole: - find_async_copy() unlinks the copy (clear cp_clp, list_del_init) under async_lock; the cancel, shutdown, and sb-cancel paths drop the list-membership reference via nfs4_put_copy() after nfsd4_stop_copy(). Drop the now-redundant list_del fixup from cleanup_async_copy(). - Because unlinking hides the copy from the reaper, its cleanup_async_copy() can no longer remove the copy's s2s_cp_stateids entry; the cancel/shutdown/sb-cancel paths now call nfs4_free_copy_state() themselves (while cp_clp is still valid) so the entry does not dangle at freed memory for the laundromat and manage_cpntf_state() to dereference. - Give the kthread its own reference, taken in nfsd4_copy() before wake_up_process() and dropped at the end of nfsd4_do_async_copy(); call wake_up_process() before list_add(). - Pin the task_struct with get_task_struct() in nfsd4_copy(), released in nfs4_put_copy(), so kthread_stop() is safe whenever the kthread exits. Set NFSD4_COPY_F_STOPPED only in nfsd4_stop_copy(), which now always kthread_stop()s before release_copy_files(); completion is still reported via NFSD4_COPY_F_COMPLETED, so nfsd4_has_active_async_copies() is unaffected. Each teardown caller removes the copy from clp->async_copies first, so kthread_stop() runs exactly once. - Take a copy reference in nfsd4_send_cb_offload(), dropped in nfsd4_cb_offload_release(). The kthread still holds its own reference there, so the refcount_inc() cannot race the final free. - Read cp_clp with smp_load_acquire() to pair with the unordered set_bit()/clear_bit() writers (Documentation/atomic_bitops.rst). Fixes: e0639dc5805a ("NFSD introduce async copy feature") Cc: stable@vger.kernel.org Fixes: ac0514f4d198 ("NFSD: Add a laundromat reaper for async copy state") Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-2-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: fix cpntf publish race in nfs4_init_cp_stateChris Mason
nfs4_alloc_init_cpntf_state() published the new cpntf entry into the s2s_cp_stateids IDR (with cs_type set) in one s2s_cp_lock section, then took the lock again to list_add() it onto p_stid->sc_cp_list. In the gap the entry is reachable by so_id but cp_list is still {NULL,NULL} from kzalloc. A racing OFFLOAD_CANCEL (so_id is echoed to the client as cnr_stateid, so any NFSv4.2 client can drive it) reaches manage_cpntf_state() -> _free_cpntf_state_locked() and does list_del() on the zeroed list_head, oopsing the server. Fold the cs_type assignment and the list_add() into the same critical section as idr_alloc_cyclic(), so a concurrent lookup either misses the entry or sees a fully linked cp_list. INIT_LIST_HEAD() the entry after allocation and switch _free_cpntf_state_locked() to list_del_init() so a stale unlink is a no-op. nfs4_init_copy_state() passes NULL p_stid and skips the list_add, preserving NFS4_COPY_STID semantics. Fixes: 624322f1adc5 ("NFSD add COPY_NOTIFY operation") Cc: stable@vger.kernel.org Assisted-by: kres:claude-opus-4-7 Signed-off-by: Chris Mason <clm@meta.com> Link: https://patch.msgid.link/20260710-nfsd-testing-v3-1-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Release the export reference when reaping open stateidsChuck Lever
nfs4_put_stid() releases the svc_export tracked in nfs4_stid.sc_export, but free_ol_stateid_reaplist() frees open and lock stateids by calling ->sc_free() directly, bypassing that path. An open stateid takes an sc_export reference in nfs4_open() and a lock stateid takes its own in init_lock_stateid(); both reach free_ol_stateid_reaplist() through their normal teardown, the open stateid via release_open_stateid() and the lock stateid via nfsd4_release_lockowner(), each through put_ol_stateid_locked(). The reference is therefore never dropped, pinning the export and blocking unmount for the lifetime of the stateid. Release sc_export in free_ol_stateid_reaplist() the way nfs4_put_stid() does. ->sc_free() runs once per stateid, and a stateid reaches free_ol_stateid_reaplist() or nfs4_put_stid() but never both, so the reference is dropped exactly once. Revoked stateids reach this path with sc_export already cleared by drop_stid_export(), so they are skipped rather than double-freed. nfs4_put_stid() itself read sc_export before acquiring cl_lock. drop_stid_export() clears that field and releases the reference under cl_lock, so a concurrent revocation could drop the export in the window between the read and the final put, releasing the same reference twice. Read sc_export while cl_lock is held so the two paths serialize and the reference is released exactly once. Fixes: ba0cde5dc81d ("NFSD: Track svc_export in nfs4_stid") Reported-by: sashiko-bot <sashiko-bot@kernel.org> Closes: https://sashiko.dev/#/patchset/20260707-cel-v3-0-7c0cc16fd54f@kernel.org?part=9 Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-9-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Prevent client use-after-free during close_lru reapingChuck Lever
An nfs4_openowner left on nn->close_lru after its final CLOSE keeps its last closed stateid in oo_last_closed_stid, holding only a raw pointer to its nfs4_client. The laundromat reaps timed-out entries, drops nn->client_lock, and calls nfs4_put_stid(), which dereferences the client through cl_lock. Nothing pins the client across that window, so a concurrent force_expire_client() can free it and nfs4_put_stid() reads freed memory. __destroy_client() hits the same race, walking clp->cl_openowners without cl_lock. Pin the client with cl_rpc_users before dropping client_lock, and skip clients already expiring. __destroy_client() then cleans up its own close_lru entries through release_last_closed_stateid(), so teardown no longer races the laundromat. Fixes: 217526e7ecc9 ("nfsd: protect the close_lru list and oo_last_closed_stid with client_lock") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-8-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Prevent client use-after-free during blocked-lock reapingChuck Lever
A bare lock owner -- its only remaining reference a blocked lock on nn->blocked_locks_lru -- holds a raw pointer to its nfs4_client but no reference keeping the client alive. When the per-net laundromat reaps such a lock, freeing the nbl drops the owner reference held through flc_owner, and the final nfs4_put_stateowner() takes the client's cl_lock. Because the laundromat detaches the nbl first, __destroy_client() no longer finds it, so a concurrent force_expire_client() can free the client before nfs4_put_stateowner() runs, dereferencing cl_lock in freed memory. Pin the client with cl_rpc_users before dropping nn->blocked_locks_lock, and skip clients already expiring, whose blocked locks __destroy_client() frees while holding an owner reference. Take nn->client_lock outside nn->blocked_locks_lock. Every other site holds nn->blocked_locks_lock as a leaf, acquiring no further lock, so placing nn->client_lock outside it cannot form a lock-order cycle. Fixes: 7919d0a27f1e ("nfsd: add a LRU list for blocked locks") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-7-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Consolidate the revocation-path client unpinChuck Lever
The client use-after-free fixes in the state-revocation paths left four open-coded copies of one idiom: drop a cl_rpc_users pin without renewing the client's lease, waking force_expire_client() when the last pin drops on a client it is tearing down. The accompanying "do not renew" rationale was documented at only one of the four sites. put_client_renew_locked() and put_client_renew() already carry the same pin-drop logic, but they renew a non-expired client's lease and so would resurrect the client whose state is being revoked. Factor the common pin-drop into __put_client_locked(), parameterized by whether to renew. The renew helpers pass true; the new put_client_no_renew_locked() and put_client_no_renew() pass false and carry the revocation paths, which must not revive the client they are tearing down. No change in behavior. Reviewed-by: NeilBrown <neil@brown.name> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-6-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Prevent client use-after-free during NFSv4.0 revoked-state cleanupChuck Lever
nfs40_clean_admin_revoked() takes a stateid reference under clp->cl_lock, drops nn->client_lock, and calls nfsd4_drop_revoked_stid(), which dereferences the stateid's client through s->sc_client->cl_lock. The stateid reference does not pin the client, so a teardown racing the dropped lock can free the client while nfsd4_drop_revoked_stid() is still using it. This cleanup runs from the laundromat, so a periodic sweep can race force_expire_client() driven by a write to the clients/<id>/ctl file. Skip a client that is already expiring and otherwise pin it with cl_rpc_users under client_lock before dropping the lock, matching nfsd4_revoke_states(). Fixes: d688d8585e6b ("nfsd: allow admin-revoked NFSv4.0 state to be freed.") Cc: stable@vger.kernel.org Reviewed-by: NeilBrown <neil@brown.name> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-5-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Prevent client use-after-free during export state revocationChuck Lever
nfsd4_revoke_export_states() has the same use-after-free as nfsd4_revoke_states(): it drops nn->client_lock across revoke_one_stid() and the following read of clp->cl_minorversion, but the stateid reference it holds does not pin the client. A teardown racing the dropped lock can free the client while revoke_one_stid() still dereferences it. exportfs -u drives this path through NFSD_CMD_UNLOCK_EXPORT, so an administrator removing an export can race a client expiry. Skip a client that is already expiring and otherwise pin it with cl_rpc_users under client_lock before dropping the lock, matching nfsd4_revoke_states(). Fixes: 2eac189bb059 ("NFSD: Add NFSD_CMD_UNLOCK_EXPORT netlink command") Reviewed-by: NeilBrown <neil@brown.name> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-4-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Prevent client use-after-free during admin state revocationChuck Lever
A stateid holds only a bare pointer to its nfs4_client; a stateid reference does not pin it. The client survives only because __destroy_client() drains its stateids before free_client() runs. nfsd4_revoke_states() drops nn->client_lock across revoke_one_stid(), which dereferences the client to revoke a stateid and read clp->cl_minorversion. A teardown racing the dropped lock can free the client first. Pinning cl_rpc_users under client_lock blocks the DESTROY_CLIENTID and EXCHANGE_ID teardown, which refuses while cl_rpc_users is non-zero. force_expire_client() ignores it: once its wait for cl_rpc_users to reach zero has passed, a later pin goes unnoticed. Under client_lock, skip a client whose cl_time is already zero -- force_expire_client() clears it there before waiting -- otherwise pin cl_rpc_users before dropping the lock. The walk then either sees the expiry and skips, or pins in time for that wait to cover the revoke. Fixes: 1c13bf9f2e3c ("nfsd: allow lock state ids to be revoked and then freed") Cc: stable@vger.kernel.org Reviewed-by: NeilBrown <neil@brown.name> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-3-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Prevent client use-after-free during delegation revokeChuck Lever
A delegation stateid holds only a bare pointer to its owning nfs4_client and does not keep it alive. The client survives its stateids only because __destroy_client() drains cl_delegations and cl_revoked before free_client() runs. nfs4_laundromat() breaks that invariant: it unhashes an expired delegation from cl_delegations, drops deleg_lock, then revoke_delegation() relinks it onto cl_revoked under cl_lock. In that window the delegation is on neither list, so client_has_state() can report no remaining state. Every teardown path first requires cl_rpc_users to be zero, but the laundromat holds no such reference. A client whose recalled delegation has just timed out can therefore reach free_client() while revoke_delegation() is still about to dereference cl_lock, a use-after-free. Pin the client with cl_rpc_users across the revoke so teardown blocks until it completes, then reap the delegation from cl_revoked. A client already expiring reaps its own, so skip it and leave the delegation on del_recall_lru. Fixes: 3bd64a5ba171 ("nfsd4: implement SEQ4_STATUS_RECALLABLE_STATE_REVOKED") Cc: stable@vger.kernel.org Reviewed-by: NeilBrown <neil@brown.name> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-2-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Prevent lock owner use-after-free during client teardownChuck Lever
__destroy_client() releases a client's open owners, but a lock owner whose only reference is a blocked lock (nbl) stays on cl_ownerstr_hashtbl. client_has_state() does not count a bare owner, so DESTROY_CLIENTID can reach __destroy_client() with such owners present. __destroy_client() then walks the table, calling remove_blocked_locks() on each owner without a reference. Freeing a blocked lock drops the owner reference held via flc_owner. The per-net laundromat reaps blocked locks from nn->blocked_locks_lru independently of client state. The two paths share blocked_locks_lock only for the list splice, not the owner's lifetime. The laundromat therefore frees the owner as __destroy_client() dereferences it, a NULL dereference in remove_blocked_locks(). nfsd4_release_lockowner() holds a reference across the same call; __destroy_client() does not. Hold cl_lock across the walk, taking a reference and unhashing each owner, then drop it before remove_blocked_locks() and nfs4_put_stateowner(), which take blocked_locks_lock and cl_lock. Reported-by: Wolfgang Walter <linux@stwm.de> Closes: https://lore.kernel.org/linux-nfs/6eccafaaaa60651ef091257c3439c46b@stwm.de/ Fixes: 68ef3bc31664 ("nfsd: remove blocked locks on client teardown") Cc: stable@vger.kernel.org Reviewed-by: NeilBrown <neil@brown.name> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260709-cel-v4-1-1d519d9be0cb@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: derive the pool count instead of caching it in sv_nrpoolsJeff Layton
Now that the pool mode is always pernode, svc_serv.sv_nrpools is redundant with sv_is_pooled: an unpooled service always has a single pool, and a pooled service has svc_pool_map.npools pools (which is one on a single-node host). sv_nrpools cannot distinguish an unpooled service from a pooled service that happens to have one pool, so it is sv_nrpools, not sv_is_pooled, that carries no unique information. Replace the cached field with a svc_serv_nrpools() helper that derives the count from sv_is_pooled and the pool map, and convert all readers to it. svc_pool_map is file-local to svc.c, so export the helper for the svc_xprt.c and nfsd callers. Reading svc_pool_map.npools without svc_pool_map_mutex is safe: the mutex protects only svc_pool_map.count, and npools is already read locklessly in svc_pool_for_cpu(). A pooled service holds a map reference for its whole lifetime, so npools is stable while any reader could observe it. The hot path (svc_pool_for_cpu()) already dereferences svc_pool_map for to_pool, and npools shares that cacheline, so there is no new locking or coherence cost. __svc_create() keeps using its local npools argument for the sv_pools[] allocation, since sv_is_pooled is not set until svc_create_pooled() has returned from it. Doing this also removes a modulus operation from svc_pool_for_cpu(), which should make for more efficient RPC queueing. Assisted-by: Claude:claude-opus-4-8 Suggested-by: NeilBrown <neilb@ownmail.net> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260706-sunrpc-pool-mode-v5-5-6c4ee7cd89aa@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10lockd: Regenerate NLMv4 XDR codeChuck Lever
The checked-in NLMv4 xdrgen output predates the addition of enum value validation to generated decoders. As a result the decoders for fsh4_mode, fsh4_access, and nlm4_stats still accept any 32-bit value, while the current generator rejects values outside the enumeration. Resync the generated files with the in-tree xdrgen by regenerating from the unchanged nlm4.x specification. This is a plain regeneration with no specification change; it also refreshes the recorded specification modification time to show that all existing enum decoders have picked up the xdrgen tool fix. Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260630155638.874492-1-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Replace isdotent() macroChuck Lever
The VFS provides name_is_dot_dotdot() as the canonical helper for recognizing the "." and ".." directory entries, and fs/ already uses it widely. nfsd has instead carried its own open-coded isdotent() macro that computes the same predicate for non-empty names, a needless duplicate of shared functionality. The macro reads the first name byte without first confirming the name is non-empty; name_is_dot_dotdot() tests the length first, so it never touches a zero-length buffer. Convert every isdotent() call site to the generic helper and remove the macro. Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260621213535.539450-1-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10NFSD: Guard admin state-revocation walks with NFSD_NET_UPChuck Lever
Writing to /proc/fs/nfsd/unlock_filesystem, or sending the NFSD_CMD_UNLOCK_FILESYSTEM or NFSD_CMD_UNLOCK_EXPORT netlink command, walks the NFSv4 client hash tables to revoke open state and cancel async COPY operations. All three handlers gate that walk on nn->nfsd_serv, but a listener added via portlist or netlink listener_set sets nn->nfsd_serv before any nfsd thread starts. nfsd_startup_net() has not yet allocated nn->conf_id_hashtbl, so the walkers dereference a NULL table. A local administrator with CAP_SYS_ADMIN can crash the kernel this way without ever starting the server. nn->nfsd_serv is set when the service is created, which precedes table allocation. NFSD_NET_UP instead brackets the window where the tables are live: set at the end of nfsd_startup_net() and cleared in nfsd_shutdown_net() after they are freed, both under nfsd_mutex. Gating the three unlock paths on NFSD_NET_UP fixes the startup-time NULL dereference while preserving the earlier post-shutdown use-after-free fix. Reported-by: XIAO WU <xiaowu.417@qq.com> Fixes: 1ac3629bf012 ("nfsd: prepare for supporting admin-revocation of state") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260621162551.2469460-1-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: add support to CB_NOTIFY for dir attribute changesJeff Layton
If the client requested dir attribute change notifications, send those alongside any set of add/remove/rename events. Note that the server will still recall the delegation on a SETATTR, so these are only sent for changes to child dirents. Signed-off-by: Jeff Layton <jlayton@kernel.org> [ cel: folded "nfsd: fix CB_NOTIFY workqueue loop when queue overflows" ] [ cel: folded "nfsd: recall deleg if a requested dir attr change can't be encoded" ] Link: https://patch.msgid.link/20260616-dir-deleg-v7-20-6cbc7eac0ade@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: track requested dir attributesJeff Layton
Track the union of requested and supported dir attributes in the delegation. In a later patch this will be used to ensure that we only encode the attributes in that union when sending add/remove/rename updates. Since the requested dir attributes can now include word1 attributes, gddr_dir_attributes[1] may be non-zero and nfsd4_encode_bitmap4() can emit a two-word bitmap. Bump the dir-attribute bitmap budget in nfsd4_get_dir_delegation_rsize() from one word to two accordingly, so the reply-size check before this non-idempotent op accounts for the larger encoding. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260616-dir-deleg-v7-19-6cbc7eac0ade@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: properly track requested child attributesJeff Layton
Track the union of requested and supported child attributes in the delegation, and only encode the attributes in that union when sending add/remove/rename updates. Since the requested child attributes can now include word1 attributes, gddr_child_attributes[1] may be non-zero and nfsd4_encode_bitmap4() can emit a two-word bitmap. Bump the child-attribute bitmap budget in nfsd4_get_dir_delegation_rsize() from one word to two accordingly, so the reply-size check before this non-idempotent op accounts for the larger encoding. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260616-dir-deleg-v7-18-6cbc7eac0ade@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: fix reply size estimate for GET_DIR_DELEGATIONJeff Layton
nfsd4_get_dir_delegation_rsize() returns its estimate in XDR words, but the COMPOUND reply-size machinery works in bytes: every other op's _rsize helper multiplies its word count by sizeof(__be32). Since GET_DIR_DELEGATION is OP_MODIFIES_SOMETHING, this estimate is consulted before the op executes to ensure the reply will fit. The ~4x too-small estimate lets a compound near the session/reply limit pass the check, grant a directory delegation, and then fail to encode the reply with NFS4ERR_RESOURCE/REP_TOO_BIG, leaving the client without the returned stateid. Multiply the estimate by sizeof(__be32) like the other _rsize helpers. Fixes: 33a1e6ea73e5 ("nfsd: trivial GET_DIR_DELEGATION support") Cc: stable@vger.kernel.org Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260616-dir-deleg-v7-17-6cbc7eac0ade@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: add the filehandle to returned attributes in CB_NOTIFYJeff Layton
nfsd's usual fh_compose routine requires a svc_export and fills out a svc_fh, which is more machinery than a CB_NOTIFY callback needs. Add a new routine that composes a filehandle from just the parent filehandle in the nfs4_file and the child dentry, and use it to fill out the fhandle field in the nfsd4_fattr_args. Signed-off-by: Jeff Layton <jlayton@kernel.org> [ cel: fold "nfsd: fix NULL deref / UAF of sc_export in setup_notify_fhandle" ] Link: https://patch.msgid.link/20260616-dir-deleg-v7-16-6cbc7eac0ade@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10nfsd: allow encoding a filehandle into fattr4 without a svc_fhJeff Layton
The current fattr4 encoder requires a svc_fh in order to encode the filehandle. This is not available in a CB_NOTIFY callback. Add a new "fhandle" field to struct nfsd4_fattr_args and copy the filehandle into there from the svc_fh. CB_NOTIFY will populate it via other means. A filehandle composed this way may still need a MAC appended on signed exports, so generalize fh_append_mac() to operate on a bare knfsd_fh (plus its maximum size and net) rather than a svc_fh. The FSID attribute shares the same attrmask gate as the filehandle, so do the same for it: add fsid_source_fh() which takes a bare knfsd_fh and its svc_export, and have the FSID encoder use args->fhandle and args->exp. fsid_source() becomes a wrapper for the v2/v3 callers. The now-unused svc_fh pointer is dropped from struct nfsd4_fattr_args. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260616-dir-deleg-v7-15-6cbc7eac0ade@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>