kernel/linux.git/fs/nfsd, branch v6.6.148

NFSD: pass nfsd_file to nfsd_iter_read()

2026-08-03T09:15:37+00:00

[ Upstream commit 803bc849f0039291f546ba0e2237faebeb5c073e ] Prepare for nfsd_iter_read() to use the DIO alignment stored in nfsd_file by passing the nfsd_file to nfsd_iter_read() rather than just the file which is associaed with the nfsd_file. This means nfsd4_encode_readv() now also needs the nfsd_file rather than the file. Instead of changing the file arg to be the nfsd_file, we discard the file arg as the nfsd_file (and indeed the file) is already available via the "read" argument. Signed-off-by: Mike Snitzer Reviewed-by: Jeff Layton Reviewed-by: NeilBrown Reviewed-by: Christoph Hellwig Signed-off-by: Chuck Lever Stable-dep-of: 18c1cc698861 ("SUNRPC: Return an error from xdr_buf_to_bvec() on overflow") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

nfsd: change nfs4_client_to_reclaim() to allocate data

2026-07-24T14:02:37+00:00

[ Upstream commit 4552f4e3f2c96597914f07b060d5c5db84420ddd ] The calling convention for nfs4_client_to_reclaim() is clumsy in that the caller needs to free memory if the function fails. It is much cleaner if the function frees its own memory. This patch changes nfs4_client_to_reclaim() to re-allocate the .data fields to be stored in the newly allocated struct nfs4_client_reclaim, and to free everything on failure. __cld_pipe_inprogress_downcall() needs to allocate the data anyway to copy it from user-space, so now that data is allocated twice. I think that is a small price to pay for a cleaner interface. Signed-off-by: NeilBrown Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

nfsd: move name lookup out of nfsd4_list_rec_dir()

2026-07-24T14:02:37+00:00

[ Upstream commit 89bd77cf436bf25e448817a662ebf76515f22863 ] nfsd4_list_rec_dir() is called with two different callbacks. One of the callbacks uses vfs_rmdir() to remove the directory. The other doesn't use the dentry at all, just the name. As only one callback needs the dentry, this patch moves the lookup into that callback. This prepares of changes to how directory operations are locked. Signed-off-by: NeilBrown Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Stable-dep-of: 4552f4e3f2c9 ("nfsd: change nfs4_client_to_reclaim() to allocate data") Signed-off-by: Sasha Levin

nfsd: Don't reset the write verifier on a commit EAGAIN

2026-07-24T14:02:37+00:00

[ Upstream commit 1b2021bdeeca12364ad0fa7aac9ddba5cae964f3 ] If fsync() is returning EAGAIN, then we can assume that the filesystem being exported is something like NFS with the 'softerr' mount option enabled, and that it is just asking us to replay the fsync() operation at a later date. If we see an ESTALE, then ditto: the file is gone, so there is no danger of losing the error. For those cases, do not reset the write verifier. A write verifier change has a global effect, causing retransmission by all clients of all uncommitted unstable writes for all files, so it is worth mitigating where possible. Link: https://lore.kernel.org/linux-nfs/20230911184357.11739-1-trond.myklebust@hammerspace.com/ Signed-off-by: Trond Myklebust Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Stable-dep-of: 2090b05803fa ("nfsd: reset write verifier on deferred writeback errors") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

nfsd: reset write verifier on deferred writeback errors

2026-07-24T14:02:35+00:00

commit 2090b05803faab8a9fa62fbff871007862cac1b7 upstream. nfsd_vfs_write() and nfsd_commit() both call filemap_check_wb_err() to detect deferred writeback errors, but neither rotates the server's write verifier (nn->writeverf) when this check fails. Every other durable-storage-failure path in these functions calls commit_reset_write_verifier() before returning an error. The missing rotation means clients holding UNSTABLE write data under the current verifier will COMMIT, receive the unchanged verifier back, and conclude their data is durable — silently dropping data that failed writeback. This violates the UNSTABLE+COMMIT durability contract (RFC 1813 §3.3.7, RFC 8881 §18.32). Add commit_reset_write_verifier() calls at both filemap_check_wb_err() error sites, matching the pattern used by adjacent error paths in the same functions. The helper already filters -EAGAIN and -ESTALE internally, so the calls are unconditionally safe. Reported-by: Chris Mason Fixes: 555dbf1a9aac ("nfsd: Replace use of rwsem with errseq_t") Cc: stable@vger.kernel.org Assisted-by: kres:claude-opus-4-6 Signed-off-by: Jeff Layton Signed-off-by: Chuck Lever [ cel: 6.6.y predates the commit_reset_write_verifier() helper (v6.7); open-coded nfsd_reset_write_verifier() and the reset tracepoint at both sites, matching the other reset paths in these functions ] Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

nfsd: release layout stid on setlease failure

2026-07-24T14:02:35+00:00

commit 30d55c8aabb261bc3f427d6b9aae7ef6206063f9 upstream. nfs4_alloc_stid() publishes the new stid into cl->cl_stateids via idr_alloc_cyclic() under cl_lock before returning to nfsd4_alloc_layout_stateid(). When nfsd4_layout_setlease() then fails, the error path frees the layout stateid directly with kmem_cache_free() without ever calling idr_remove(), leaving the IDR slot pointing at freed slab memory. Any subsequent IDR walker (states_show, client teardown) dereferences the dangling pointer. The correct teardown for an IDR-published stid is nfs4_put_stid(), which removes the IDR slot under cl_lock, dispatches sc_free (nfsd4_free_layout_stateid) to release ls->ls_file via nfsd4_close_layout(), and drops the nfs4_file reference in its tail. A second issue blocks that switch: nfsd4_free_layout_stateid() unconditionally inspects ls->ls_fence_work via delayed_work_pending() under ls_lock, but INIT_DELAYED_WORK(&ls->ls_fence_work, ...) currently runs only after the setlease call. On the setlease-failure path the destructor would touch an uninitialized delayed_work. nfsd4_alloc_layout_stateid() nfs4_alloc_stid() /* idr_alloc_cyclic under cl_lock */ nfsd4_layout_setlease() /* fails */ nfs4_put_stid() nfsd4_free_layout_stateid() delayed_work_pending(&ls->ls_fence_work) /* needs INIT */ nfsd4_close_layout() /* nfsd_file_put(ls->ls_file) */ put_nfs4_file() Fix by hoisting the ls_fenced / ls_fence_delay / INIT_DELAYED_WORK initialization above the nfsd4_layout_setlease() call, and replace the manual nfsd_file_put + put_nfs4_file + kmem_cache_free cleanup with a single nfs4_put_stid(stp). Fixes: c5c707f96fc9 ("nfsd: implement pNFS layout recalls") Cc: stable@vger.kernel.org Assisted-by: kres (claude-opus-4-7) Signed-off-by: Chris Mason Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever [ cel: no ls_fence_work in 6.6.y; dropped INIT_DELAYED_WORK hunk ] Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

nfsd: check get_user() return when reading princhashlen

2026-07-04T11:42:27+00:00

commit e186fa1c057f5eccb22afb1e83e34c0627085868 upstream. In __cld_pipe_inprogress_downcall(), the get_user() that reads princhashlen from the userspace cld_msg_v2 buffer does not check its return value. A failing copy leaves princhashlen with uninitialised stack contents, which are then used to drive memdup_user() and stored as princhash.len on the resulting reclaim record. The other get_user() calls in this function all check the return; only this one is missed, which is most likely a copy-paste oversight from when v2 upcalls were introduced. Mirror the existing pattern used a few lines above for namelen. namecopy is declared with __free(kfree) so the early return cleans up the already-allocated buffer automatically. Fixes: 6ee95d1c8991 ("nfsd: add support for upcall version 2") Cc: stable@vger.kernel.org Signed-off-by: Dominik Woźniak Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman

nfsd: fix posix_acl leak on SETACL decode failure

2026-07-04T11:42:27+00:00

commit 0853ac544c590880d797b04daa33fcb72b6be0e1 upstream. nfsaclsvc_decode_setaclargs() and nfs3svc_decode_setaclargs() each call nfs_stream_decode_acl() twice, first for NFS_ACL and then for NFS_DFACL. Each successful call transfers ownership of a freshly allocated posix_acl into argp->acl_access or argp->acl_default. If the first call succeeds but the second fails, the decoder returns false and argp->acl_access is left dangling. ACLPROC2_SETACL.pc_release was wired to nfssvc_release_attrstat and ACLPROC3_SETACL.pc_release was wired to nfs3svc_release_fhandle. Both only call fh_put() and have no knowledge of the ACL fields on argp. The posix_acl_release() pairs sat at the out: labels inside nfsacld_proc_setacl() and nfsd3_proc_setacl(), but svc_process() skips pc_func when pc_decode returns false, so that cleanup is unreachable on decode failure: svc_process_common() pc_decode() /* decode_setaclargs: false */ /* pc_func skipped */ pc_release() /* fh_put only -- ACLs leaked */ The orphaned posix_acl is leaked for the lifetime of the server. Fix by adding nfsaclsvc_release_setacl() and nfs3svc_release_setacl(), which release both argp->acl_access and argp->acl_default in addition to fh_put(), and wiring them as pc_release for their respective SETACL procedures. pc_release runs on every path svc_process() takes after decode, including decode failure, so the posix_acl_release() pairs are removed from the proc functions' out: labels to keep ownership in one place. This matches the existing release_getacl() pattern used by the sibling GETACL procedures. Fixes: a257cdd0e217 ("[PATCH] NFSD: Add server support for NFSv3 ACLs.") Cc: stable@vger.kernel.org Assisted-by: kres:claude-opus-4-7 Signed-off-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman

NFSD: Fix SECINFO_NO_NAME decode error cleanup

2026-07-04T11:42:27+00:00

commit 9e18e83b8846a5c3fe13fc8a464b4865d33996c6 upstream. nfsd4_decode_secinfo_no_name() currently initializes sin_exp after decoding sin_style. If the XDR stream is truncated, the decoder returns nfserr_bad_xdr before sin_exp is initialized. Since commit 3fdc54646234 ("NFSD: Reduce amount of struct nfsd4_compoundargs that needs clearing"), the inline iops array is not cleared between RPC calls. A failed SECINFO_NO_NAME decode can therefore leave sin_exp holding stale union contents from a previous operation. The error response path still invokes nfsd4_secinfo_no_name_release(), which calls exp_put() on a non-NULL sin_exp. Initialize sin_exp before the first failable decode step, matching nfsd4_decode_secinfo(). Fixes: 3fdc54646234 ("NFSD: Reduce amount of struct nfsd4_compoundargs that needs clearing") Cc: stable@vger.kernel.org Signed-off-by: Guannan Wang Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman

nfsd: fix heap overflow in NFSv4.0 LOCK replay cache

2026-03-25T10:06:03+00:00

[ Upstream commit 5133b61aaf437e5f25b1b396b14242a6bb0508e2 ] The NFSv4.0 replay cache uses a fixed 112-byte inline buffer (rp_ibuf[NFSD4_REPLAY_ISIZE]) to store encoded operation responses. This size was calculated based on OPEN responses and does not account for LOCK denied responses, which include the conflicting lock owner as a variable-length field up to 1024 bytes (NFS4_OPAQUE_LIMIT). When a LOCK operation is denied due to a conflict with an existing lock that has a large owner, nfsd4_encode_operation() copies the full encoded response into the undersized replay buffer via read_bytes_from_xdr_buf() with no bounds check. This results in a slab-out-of-bounds write of up to 944 bytes past the end of the buffer, corrupting adjacent heap memory. This can be triggered remotely by an unauthenticated attacker with two cooperating NFSv4.0 clients: one sets a lock with a large owner string, then the other requests a conflicting lock to provoke the denial. We could fix this by increasing NFSD4_REPLAY_ISIZE to allow for a full opaque, but that would increase the size of every stateowner, when most lockowners are not that large. Instead, fix this by checking the encoded response length against NFSD4_REPLAY_ISIZE before copying into the replay buffer. If the response is too large, set rp_buflen to 0 to skip caching the replay payload. The status is still cached, and the client already received the correct response on the original request. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@kernel.org Reported-by: Nicholas Carlini Tested-by: Nicholas Carlini Signed-off-by: Jeff Layton Signed-off-by: Chuck Lever [ replaced `op_status_offset + XDR_UNIT` with existing `post_err_offset` variable ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman