kernel/linux.git/fs/nfsd, branch v7.0.10

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

2026-05-23T11:09:41+00:00

commit 4183cf383b6faec17a0882b84cd2d901dba62b16 upstream. 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 Signed-off-by: Greg Kroah-Hartman

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

2026-05-23T11:09:40+00:00

commit 2863bac7f49c4acd80a048ce52506a2b9c8db015 upstream. 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 Signed-off-by: Greg Kroah-Hartman

nfsd: fix file change detection in CB_GETATTR

2026-05-23T11:09:40+00:00

commit 304d81a2fbf2b454def4debcb38ea173911b72cd upstream. 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 Signed-off-by: Greg Kroah-Hartman

nfsd: fix GET_DIR_DELEGATION when VFS leases are disabled

2026-05-23T11:09:40+00:00

commit b0bf14546bcefa4ea49f5efcd7db2a99f0cabde9 upstream. 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 Signed-off-by: Greg Kroah-Hartman

nfsd: use dynamic allocation for oversized NFSv4.0 replay cache

2026-05-23T11:09:11+00:00

[ Upstream commit 116b6b7acdd82605ed530232cd7509d1b5282f5c ] Commit 1e8e9913672a ("nfsd: fix heap overflow in NFSv4.0 LOCK replay cache") capped the replay cache copy at NFSD4_REPLAY_ISIZE to prevent a heap overflow, but set rp_buflen to zero when the encoded response exceeded the inline buffer. A retransmitted LOCK reaching the replay path then produced only a status code with no operation body, resulting in a malformed XDR response. When the encoded response exceeds the 112-byte inline rp_ibuf, a buffer is kmalloc'd to hold it. If the allocation fails, rp_buflen remains zero, preserving the behavior from the capped-copy fix. The buffer is freed when the stateowner is released or when a subsequent operation's response fits in the inline buffer. Fixes: 1e8e9913672a ("nfsd: fix heap overflow in NFSv4.0 LOCK replay cache") Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

NFSD: fix nfs4_file access extra count in nfsd4_add_rdaccess_to_wrdeleg

2026-05-23T11:09:11+00:00

[ Upstream commit b48f44f36e6607b2f818560f19deb86b4a9c717b ] In nfsd4_add_rdaccess_to_wrdeleg, if fp->fi_fds[O_RDONLY] is already set by another thread, __nfs4_file_get_access should not be called to increment the nfs4_file access count since that was already done by the thread that added READ access to the file. The extra fi_access count in nfs4_file can prevent the corresponding nfsd_file from being freed. When stopping nfs-server service, these extra access counts trigger a BUG in kmem_cache_destroy() that shows nfsd_file object remaining on __kmem_cache_shutdown. This problem can be reproduced by running the Git project's test suite over NFS. Fixes: 8072e34e1387 ("nfsd: fix nfsd_file reference leak in nfsd4_add_rdaccess_to_wrdeleg()") Signed-off-by: Dai Ngo Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

sunrpc: Kill RPC_IFDEBUG()

2026-05-23T11:09:11+00:00

[ Upstream commit adcc59114ccd402259c089b0fea24da5e4974563 ] RPC_IFDEBUG() is used in only two places. In one the user of the definition is guarded by ifdeffery, in the second one it's implied due to dprintk() usage. Kill the macro and move the ifdeffery to the regular condition with the variable defined inside, while in the second case add the same conditional and move the respective code there. Reviewed-by: Jeff Layton Signed-off-by: Andy Shevchenko Signed-off-by: Chuck Lever Stable-dep-of: 6f57293abb8d ("sunrpc: Fix compilation error (`make W=1`) when dprintk() is no-op") Signed-off-by: Sasha Levin

Merge tag 'nfsd-7.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2026-03-18T21:27:11+00:00

Pull nfsd fixes from Chuck Lever: - Fix cache_request leak in cache_release() - Fix heap overflow in the NFSv4.0 LOCK replay cache - Hold net reference for the lifetime of /proc/fs/nfs/exports fd - Defer sub-object cleanup in export "put" callbacks * tag 'nfsd-7.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: nfsd: fix heap overflow in NFSv4.0 LOCK replay cache sunrpc: fix cache_request leak in cache_release NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd NFSD: Defer sub-object cleanup in export put callbacks

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

2026-03-16T20:58:01+00:00

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

NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd

2026-03-14T15:34:25+00:00

The /proc/fs/nfs/exports proc entry is created at module init and persists for the module's lifetime. exports_proc_open() captures the caller's current network namespace and stores its svc_export_cache in seq->private, but takes no reference on the namespace. If the namespace is subsequently torn down (e.g. container destruction after the opener does setns() to a different namespace), nfsd_net_exit() calls nfsd_export_shutdown() which frees the cache. Subsequent reads on the still-open fd dereference the freed cache_detail, walking a freed hash table. Hold a reference on the struct net for the lifetime of the open file descriptor. This prevents nfsd_net_exit() from running -- and thus prevents nfsd_export_shutdown() from freeing the cache -- while any exports fd is open. cache_detail already stores its net pointer (cd->net, set by cache_create_net()), so exports_release() can retrieve it without additional per-file storage. Reported-by: Misbah Anjum N Closes: https://lore.kernel.org/linux-nfs/dcd371d3a95815a84ba7de52cef447b8@linux.ibm.com/ Fixes: 96d851c4d28d ("nfsd: use proper net while reading "exports" file") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton Reviewed-by: NeilBrown Tested-by: Olga Kornievskaia Signed-off-by: Chuck Lever