Pull NFS client updates from Anna Schumaker:
"New features:
- XPRTRDMA: Decouple req recycling from RPC completion
- NFS: Expose FMODE_NOWAIT for read-only files
Bugfixes:
- SUNRPC:
- Fix sunrpc sysfs error handling
- Fix uninitialized xprt_create_args structure
- XPRTRDMA:
- Harden connect and reply handling
- NFS:
- Fix EOF updates after fallocate/zero-range
- Keep PG_UPTODATE clear after read errors in page groups
- Use nfsi->rwsem to protect traversal of the file lock list
- Prevent resource leak in nfs_alloc_server()
- NFSv4:
- Clear exception state on successful mkdir retry
- Don't skip revalidate when holding a dir delegation and attrs are stale
- pNFS:
- Fix use-after-free in pnfs_update_layout()
- Defer return_range callbacks until after inode unlock
- Fix LAYOUTCOMMIT retry loop on OLD_STATEID
- Reject zero-length r_addr in nfs4_decode_mp_ds_addr
- NFS/flexfiles:
- Reject zero-length filehandle version arrays
- Fix checking if a layout is striped
- Fixes for honoring FF_FLAGS_NO_IO_THRU_MDS
Other cleanups and improvements:
- Remove the fileid field from struct nfs_inode
- Move long-delayed xprtrdma work onto the system_dfl_long_wq
- Convert xprtrdma send buffer free list to an llist
- Show "<redacted>" for cert_serial and privkey_serial mount options"
* tag 'nfs-for-7.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (42 commits)
NFS: Use common error handling code in nfs_alloc_server()
NFS: Prevent resource leak in nfs_alloc_server()
NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr
nfs: don't skip revalidate on directory delegation when attrs flagged stale
xprtrdma: Return sendctx slot after Send preparation failure
xprtrdma: Repost Receive buffers for malformed replies
xprtrdma: Sanitize the reply credit grant after parsing
xprtrdma: Fix bcall rep leak and unbounded peek
xprtrdma: Resize reply buffers before reposting receives
xprtrdma: Check frwr_wp_create() during connect
xprtrdma: Initialize re_id before removal registration
xprtrdma: Fix ep kref imbalance on ADDR_CHANGE
xprtrdma: Convert send buffer free list to llist
NFS: correct CONFIG_NFS_V4 macro name in #endif comment
nfs: use nfsi->rwsem to protect traversal of the file lock list
NFSv4.1/pNFS: fix LAYOUTCOMMIT retry loop on OLD_STATEID
nfs: expose FMODE_NOWAIT for read-only files
nfs: add nowait version of nfs_start_io_direct
NFSv4/flexfiles: honor FF_FLAGS_NO_IO_THRU_MDS in pg_get_mirror_count_write
NFSv4/flexfiles: honor FF_FLAGS_NO_IO_THRU_MDS on fatal DS connect errors
...
Pull nfsd updates from Chuck Lever:
"Jeff Layton wired up netlink upcalls for the auth.unix.ip and
auth.unix.gid caches in SunRPC and the svc_export and nfsd.fh caches
in NFSD. The new kernel-user API is more extensible and lays the
groundwork for retiring the old pipe interface.
The default NFS r/w block size rises to 4MB on hosts with at least
16GB of RAM, reducing per-RPC overhead on fast networks. Smaller
machines keep their previously computed default, and the value remains
tunable through /proc/fs/nfsd/max_block_size.
Chuck Lever converted the server's RPCSEC GSS Kerberos code to the
kernel's shared crypto/krb5 library. The conversion retires and
removes SunRPC's bespoke implementation of Kerberos v5, but keeps
RPCSEC GSS-API.
Continuing the xdrgen migration that converted the NLMv4 server XDR
layer in v7.1, Chuck Lever converted the NLM version 3 server-side XDR
layer from hand-written C to xdrgen-generated code. As with the NLMv4
conversion in v7.1, the goals are improved memory safety, lower
maintenance burden, and groundwork for generation of Rust code for
this layer instead of C.
Chuck Lever fixed an issue where lingering NFSv4 state pins a mounted
file system after it is unexported. A new netlink-based mechanism can
now release NLM locks and NFSv4 state by client address, by
filesystem, and by export. Now an administrator can quiesce an export
cleanly before unmounting it.
The remaining patches are bug fixes, clean-ups, and minor
optimizations, including a batch of memory-leak and use-after-free
fixes in the ACL, lockd, and TLS handshake paths, many of them
reported by Chris Mason. Sincere thanks to all contributors,
reviewers, testers, and bug reporters who participated in the v7.2
NFSD development cycle"
* tag 'nfsd-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (106 commits)
svcrdma: wake sq waiters when the transport closes
nfsd: reset write verifier on deferred writeback errors
nfsd: avoid leaking pre-allocated openowner on unconfirmed retry race
sunrpc: wait for in-flight TLS handshake callback when cancel loses race
sunrpc: pin svc_xprt across the asynchronous TLS handshake callback
nfsd: fix posix_acl leak on SETACL decode failure
nfsd: fix posix_acl leak and ignored error in nfsd4_create_file
nfsd: check get_user() return when reading princhashlen
nfsd: fix inverted cp_ttl check in async copy reaper
nfsd: fix dead ACL conflict guard in nfsd4_create
NFSD: Fix SECINFO_NO_NAME decode error cleanup
sunrpc: harden rq_procinfo lifecycle to prevent double-free
SUNRPC: Return an error from xdr_buf_to_bvec() on overflow
SUNRPC: Bound-check xdr_buf_to_bvec() stores before writing
nfsd: release layout stid on setlease failure
lockd: Avoid hashing uninitialized bytes in nlm4svc_lookup_file()
lockd: Plug nlm_file refcount leak on cached nlm_do_fopen() failure
lockd: Plug nlm_file leak when nlm_do_fopen() fails
Revert "NFSD: Defer sub-object cleanup in export put callbacks"
Revert "svcrdma: Use contiguous pages for RDMA Read sink buffers"
...
Use an additional label so that a bit of exception handling can be better
reused at the end of this function implementation.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Pull lsm update from Paul Moore:
"A single LSM update the security_inode_listsecurity() hook to be able
to leverage the xattr_list_one() helper function.
We wanted to do this for a while, but we needed to fixup the callers
in the NFS code first. With the NFS code changes shipping in Linux
v7.0 and no one complaining, it seemed a good time to complete the
shift"
* tag 'lsm-pr-20260615' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
security,fs,nfs,net: update security_inode_listsecurity() interface
nfs4_decode_mp_ds_addr() decodes the r_netid and r_addr opaques of a
netaddr4 from a GETDEVICEINFO multipath-DS body, then immediately
calls strrchr(buf, '.') to locate the port separator. Both decodes
use xdr_stream_decode_string_dup(), and the current code checks only
"nlen < 0" / "rlen < 0" before dereferencing the returned string.
When the on-wire opaque has length zero, xdr_stream_decode_opaque_inline()
returns 0 and xdr_stream_decode_string_dup() falls through to its
"*str = NULL; return ret" tail, leaving buf NULL with a return value
of 0. The "< 0" check does not catch this, and the next line is
strrchr(NULL, '.'), a kernel NULL pointer dereference reachable from
any pNFS-flexfile client mounted against a malicious or compromised
metadata server.
Reject the zero-length cases explicitly so the decoder fails with
-EBADMSG (treated as a malformed GETDEVICEINFO body) instead of
panicking the client.
Cc: stable@vger.kernel.org
Fixes: 6b7f3cf963 ("nfs41: pull decode_ds_addr from file layout to generic pnfs")
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
On a local directory mutation (rename/create/unlink) the client marks
CHANGE / MTIME / CTIME as invalid in NFS_I(dir)->cache_validity. When
a subsequent stat(2) enters __nfs_revalidate_inode() and finds a
directory delegation held, the function currently early-exits and
returns the cached (now stale) mtime to userspace without sending a
GETATTR RPC.
Keep the early-exit for the fast path, but take the RPC when CHANGE,
MTIME, or CTIME are already marked invalid. The delegation alone is
not a guarantee of cached-attr freshness once the code itself has
flagged the cache as stale.
Assisted-by: Claude:claude-opus-4-7 [bpftrace] [tshark]
Signed-off-by: Tom Haynes <loghyr@gmail.com>
[Anna: Use NFS_INO_INVALID_ATTR insteado of individual NFS_INO_INVALID_* flags]
Signed-off-by: Anna Schumaker <anna@kernel.org>
Pull dcache updates from Al Viro:
- d_alloc_parallel() API change (Neil's with my changes)
- NORCU fixes
- Reorganization and simplification of dentry eviction logic
- Simplifying rcu_read_lock() scopes in fs/dcache.c
- Secondary roots work - getting rid of NFS fake root dentries and
dealing with remaining shrink_dcache_for_umount() and
shrink_dentry_list() races
- making cursors NORCU (surprisingly easy)
* tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (22 commits)
make cursors NORCU
nfs: get rid of fake root dentries
wind ->s_roots via ->d_sib instead of ->d_hash
shrink_dentry_tree(): unify the calls of shrink_dentry_list()
shrinking rcu_read_lock() scope in d_alloc_parallel()
d_walk(): shrink rcu_read_lock() scope
document dentry_kill()
adjust calling conventions of lock_for_kill(), fold __dentry_kill() into dentry_kill()
Document rcu_read_lock() use in select_collect2()
Shift rcu_read_{,un}lock() inside fast_dput()
simplify safety for lock_for_kill() slowpath
fold lock_for_kill() and __dentry_kill() into common helper
fold lock_for_kill() into shrink_kill()
shrink_dentry_list(): start with removing from shrink list
d_prune_aliases(): make sure to skip NORCU aliases
kill d_dispose_if_unused()
make to_shrink_list() return whether it has moved dentry to list
select_collect(): ignore dentries on shrink lists if they have positive refcounts
find_acceptable_alias(): skip NORCU aliases with zero refcount
fix a race between d_find_any_alias() and final dput() of NORCU dentries
...
Pull misc vfs updates from Christian Brauner:
"Features:
- Reduce pipe->mutex contention by pre-allocating pages outside the
lock in anon_pipe_write().
anon_pipe_write() called alloc_page() once per page while holding
pipe->mutex. The allocation can sleep doing direct reclaim and runs
memcg charging, which extends the critical section and stalls any
concurrent reader on the same mutex. Now up to 8 pages are
pre-allocated before the mutex is taken, leftovers are recycled
into the per-pipe tmp_page[] cache before unlock, and any remainder
is released after unlock, keeping the allocator out of the critical
section on both sides. On a writers x readers sweep with 64KB
writes against a 1 MB pipe throughput improves 6-28% and average
write latency drops 5-22%; under memory pressure - when the cost of
holding the mutex across reclaim is highest - throughput improves
21-48% and latency drops 17-33%. The microbenchmark is added to
selftests.
- uaccess/sockptr: fix the ignored_trailing logic in
copy_struct_to_user() to behave as documented and the usize check
in copy_struct_from_sockptr() for user pointers, and add
copy_struct_{from,to}_bounce_buffer() and copy_struct_to_sockptr()
helpers for upcoming users (IPPROTO_SMBDIRECT, IPPROTO_QUIC).
- bpf: add a sleepable bpf_real_inode() kfunc that resolves the real
inode backing a dentry via d_real_inode(). On overlayfs the inode
attached to the dentry doesn't carry the underlying device
information; this is used by the filesystem restriction BPF program
that was merged into systemd.
- docs: add guidelines for submitting new filesystems, motivated by
the maintenance burden abandoned and untestable filesystems impose
on VFS developers, blocking infrastructure work like folio
conversions and iomap migration.
Fixes:
- libfs: set SB_I_NOEXEC and SB_I_NODEV by default in init_pseudo()
and drop the now-redundant assignments in callers. This began as a
one-line dma-buf fix for a path_noexec() warning; a pseudo
filesystem has no reason not to set SB_I_NOEXEC. All init_pseudo()
callers were audited: the only visible effect is on dma-buf where
SB_I_NOEXEC silences the warning.
- Handle set_blocksize() failures in legacy filesystems (bfs, hpfs,
qnx4, jfs, befs, affs, isofs, minix, ntfs3, omfs). Mounting a
device with a sector size > PAGE_SIZE crashed roughly half of them;
the rest had the same missing error handling pattern. Plus a
follow-up releasing the superblock buffer_head when setting the
minix v3 block size fails.
- mount: honour SB_NOUSER in the new mount API.
- fs/fcntl: fix a SOFTIRQ-unsafe lock order in fasync signaling by
switching the process-group paths of send_sigio() and send_sigurg()
from read_lock(&tasklist_lock) to RCU, matching the single-PID
path.
- vfs: add an FS_USERNS_DELEGATABLE flag and set it for NFS, fixing
delegated NFS mounts (fsopen() in a container with the mount
performed by a privileged daemon) that broke when non-init
s_user_ns was tied to FS_USERNS_MOUNT.
- selftests/namespaces: fix a hang in nsid_test where an unreaped
grandchild kept the TAP pipe write-end open, a waitpid(-1) race in
listns_efault_test, and a false FAIL on kernels without listns()
where the tests should SKIP.
- filelock: fix the break_lease() stub signature for
CONFIG_FILE_LOCKING=n.
- init/initramfs_test: wait for the async initramfs unpacking before
running; the test and do_populate_rootfs() share the parser state.
- fs/coredump: reduce redundant log noise in
validate_coredump_safety().
- iomap: pass the correct length to fserror_report_io() in
__iomap_write_begin().
- backing-file: fix the backing_file_open() kerneldoc.
Cleanups:
- initramfs: refactor the cpio hex header parsing to use hex2bin()
instead of the hand-rolled simple_strntoul() which is reverted, and
extend the initramfs KUnit tests to cover header fields with 0x
prefixes.
- Replace __get_free_pages() and friends with kmalloc()/kzalloc()
across quota, proc, ocfs2/dlm, nilfs2, nfs, nfsd, libfs, jfs, jbd2,
isofs, fuse, select, namespace, configfs, binfmt_misc, bfs, and the
do_mounts init code - part of the larger work of replacing page
allocator calls with kmalloc().
- Use clear_and_wake_up_bit() in unlock_buffer() and
journal_end_buffer_io_sync() instead of open-coding the sequence.
- Drop unused VFS exports: unexport drop_super_exclusive(), remove
start_removing_user_path_at(), and fold __start_removing_path()
into start_removing_path().
- fs/read_write: narrow the __kernel_write() export with
EXPORT_SYMBOL_FOR_MODULES().
- vfs: uapi: retire octal and hex constants in favor of (1 << n) for
the O_ flags. Finding a free bit for a new flag across the
architectures was needlessly hard with the mixed bases.
- dcache: add extra sanity checks of dead dentries in dentry_free()
via a new DENTRY_WARN_ONCE() that also prints d_flags.
- iov_iter: use kmemdup_array() in dup_iter() to harden the
allocation against multiplication overflow.
- fs/pipe: write to ->poll_usage only once.
- vfs: remove an always-taken if-branch in find_next_fd().
- dcache: use kmalloc_flex() for struct external_name in __d_alloc().
- namei: use QSTR() instead of QSTR_INIT() in path_pts().
- sync_file_range: delete dead S_ISLNK code.
- Comment fixes: retire a stale comment in fget_task_next() and fix
assorted spelling mistakes"
* tag 'vfs-7.2-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (73 commits)
backing-file: fix backing_file_open() kerneldoc parameter
iomap: pass the correct len to fserror_report_io in __iomap_write_begin
vfs: add FS_USERNS_DELEGATABLE flag and set it for NFS
filelock: fix break_lease() stub signature for CONFIG_FILE_LOCKING=n
vfs: uapi: retire octal and hex numbers in favor of (1 << n) for O_ flags
bpf: add bpf_real_inode() kfunc
fs/read_write: Do not export __kernel_write() to the entire world
libfs: drop redundant SB_I_NOEXEC/SB_I_NODEV in init_pseudo() callers
libfs: set SB_I_NOEXEC and SB_I_NODEV by default in init_pseudo()
mount: honour SB_NOUSER in the new mount API
fs/fcntl: fix SOFTIRQ-unsafe lock order in fasync signaling
selftests/pipe: add pipe_bench microbenchmark
fs/pipe: pre-allocate pages outside pipe->mutex in anon_pipe_write
fs: retire stale comment in fget_task_next()
fs: fix spelling mistakes in comment
bfs: replace get_zeroed_page() with kzalloc()
binfmt_misc: replace __get_free_page() with kmalloc()
configfs: replace __get_free_pages() with kzalloc()
fs/namespace: use __getname() to allocate mntpath buffer
fs/select: replace __get_free_page() with kmalloc()
...
Pull openat2 updates from Christian Brauner:
"Features:
- Add O_EMPTYPATH to openat(2)/openat2(2). To get an operable file
descriptor from an O_PATH file descriptor it is possible to use
openat(fd, ".", O_DIRECTORY) for directories, but other file types
require going through open("/proc/<pid>/fd/<nr>") and thus depend
on a functioning procfs.
With O_EMPTYPATH an empty path string is accepted and LOOKUP_EMPTY
is set at path resolution time, allowing to reopen the file behind
the file descriptor directly. Selftests are included.
- Add an OPENAT2_REGULAR flag for openat2(2) which refuses to open
anything but regular files with the new EFTYPE error code.
This implements the "ability to only open regular files" feature
requested by userspace via uapi-group.org and protects services
from being redirected to fifos, device nodes, and friends.
All atomic_open implementations were audited for OPENAT2_REGULAR
handling. Explicit checks were added to ceph, gfs2, nfs (v4), and
cifs/smb - these are the filesystems whose atomic_open can
encounter an existing non-regular file and would otherwise call
finish_open() on it or return a misleading error code.
The remaining implementations (9p, fuse, vboxsf, nfs v2/v3) only
call finish_open() on freshly created files and use
finish_no_open() for lookup hits, letting the VFS catch non-regular
files via the do_open() safety net.
Cleanups:
- Migrate the openat2 selftests to the kselftest harness and move
them under selftests/filesystems/. The tests were written in the
early days of selftests' TAP support and the modern kselftest
harness is much easier to follow and maintain. The contents of the
tests are unchanged and the new emptypath tests are ported on top.
- Make the LAST_XXX last-type constants private to fs/namei.c. The
only user outside of fs/namei.c was ksmbd which only needs to know
whether the last component is a regular one, so
vfs_path_parent_lookup() now performs the LAST_NORM check
internally. The ints are replaced with a dedicated enum last_type"
* tag 'vfs-7.2-rc1.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
vfs: replace ints with enum last_type for LAST_XXX
vfs: make LAST_XXX private to fs/namei.c
selftests: openat2: port emptypath_test to kselftest harness
kselftest/openat2: test for OPENAT2_REGULAR flag
openat2: new OPENAT2_REGULAR flag support
openat2: introduce EFTYPE error code
selftest: add tests for O_EMPTYPATH
vfs: add O_EMPTYPATH to openat(2)/openat2(2)
selftests: openat2: migrate to kselftest harness
selftests: openat2: switch from custom ARRAY_LEN to ARRAY_SIZE
selftests: openat2: move helpers to header
selftests: move openat2 tests to selftests/filesystems/
Pull vfs casefolding updates from Christian Brauner:
"This exposes the case folding behavior of local filesystems so that
file servers - nfsd, ksmbd, and user space file servers - can report
the actual behavior to clients instead of guessing.
Filesystems report case-insensitive and case-nonpreserving behavior
via new file_kattr flags in their fileattr_get implementations. fat,
exfat, ntfs3, hfs, hfsplus, xfs, cifs, nfs, vboxsf, and isofs are
wired up. Local filesystems that are not explicitly handled default to
the usual POSIX behavior of case-sensitive and case-preserving.
nfsd uses this to report case folding via NFSv3 PATHCONF and to
implement the NFSv4 FATTR4_CASE_INSENSITIVE and FATTR4_CASE_PRESERVING
attributes - both have been part of the NFS protocols for decades to
support clients on non-POSIX systems - and ksmbd reports it via
FS_ATTRIBUTE_INFORMATION. Exposing the information through the
fileattr uapi covers user space file servers.
The immediate motivation is interoperability: Windows NFS clients
hard-require servers to report case-insensitivity for Win32
applications to work correctly, and a client that knows the server is
case-insensitive can avoid issuing multiple LOOKUP/READDIR requests
searching for case variants.
The Linux NFS client already grew support for case-insensitive shares
years ago in support of the Hammerspace NFS server - negative dentry
caching must be disabled (a lookup for "FILE.TXT" failing must not
cache a negative entry when "file.txt" exists) and directory change
invalidation must drop cached case-folded name variants. Such servers
often operate in multi-protocol environments where a single file
service instance caters to both NFS and SMB clients, and nfsd needs to
report case folding properly to participate as a first-class citizen
there.
A follow-up series brings fixes for the initial work: the nfsd
case-info probe now uses kernel credentials, maps -ESTALE to
NFS3ERR_STALE, and has its cost capped across READDIR entries; the nfs
client avoids transiently zeroed case capability bits during the probe
and skips the pathconf probe when neither field is consumed; the
FS_CASEFOLD_FL semantics are clarified in the UAPI header; and the
tools UAPI headers are synced"
* tag 'vfs-7.2-rc1.casefold' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (22 commits)
nfsd: Cap case-folding probe cost across READDIR entries
nfsd: Map -ESTALE from case probe to NFS3ERR_STALE
nfsd: Use kernel credentials for case-info probe
fs: Clarify FS_CASEFOLD_FL semantics in UAPI header
nfs: Skip pathconf probe when neither field is consumed
nfs: Avoid transient zeroed case capability bits during probe
tools headers UAPI: Sync case-sensitivity flags from linux/fs.h
ksmbd: Report filesystem case sensitivity via FS_ATTRIBUTE_INFORMATION
nfsd: Implement NFSv4 FATTR4_CASE_INSENSITIVE and FATTR4_CASE_PRESERVING
nfsd: Report export case-folding via NFSv3 PATHCONF
isofs: Implement fileattr_get for case sensitivity
vboxsf: Implement fileattr_get for case sensitivity
nfs: Implement fileattr_get for case sensitivity
cifs: Implement fileattr_get for case sensitivity
xfs: Report case sensitivity in fileattr_get
hfsplus: Report case sensitivity in fileattr_get
hfs: Implement fileattr_get for case sensitivity
ntfs3: Implement fileattr_get for case sensitivity
exfat: Implement fileattr_get for case sensitivity
fat: Implement fileattr_get for case sensitivity
...
Pull vfs inode updates from Christian Brauner:
"This extends the lockless ->i_count handling.
iput() could already decrement any value greater than one locklessly
but acquiring a reference always required taking inode->i_lock. Now
acquiring a reference is lockless as long as the count was already at
least 1, i.e., only the 0->1 and 1->0 transitions take the lock.
This avoids the lock for the common cases of nfs calling into the
inode hash and btrfs using igrab(). Cleanup-wise icount_read_once() is
added to line up with inode_state_read_once() and the open-coded
->i_count loads across the tree are converted, and ihold() is
relocated and tidied up.
On top of that some stale lock ordering annotations are retired from
the inode hash code: iunique() no longer takes the hash lock since the
inode hash became RCU-searchable and s_inode_list_lock is no longer
taken under the hash lock either"
* tag 'vfs-7.2-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fs: retire stale lock ordering annotations from inode hash
fs: allow lockless ->i_count bumps as long as it does not transition 0->1
fs: relocate and tidy up ihold()
fs: add icount_read_once() and stop open-coding ->i_count loads
A comment in fs/nfs/dir.c incorrectly refers to CONFIG_NFSV4 instead of
CONFIG_NFS_V4. Correct it.
Discovered while searching for CONFIG_* symbols referenced in code but
not defined in any Kconfig file.
Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Commit e1c5ae59c0 ("fs: don't allow non-init s_user_ns for filesystems
without FS_USERNS_MOUNT") prevents the mount of any filesystem inside a
container that doesn't have FS_USERNS_MOUNT set.
This broke NFS mounts in our containerized environment. We have a daemon
somewhat like systemd-mountfsd running in the init_ns. A process does a
fsopen() inside the container and passes it to the daemon via unix
socket.
The daemon then vets that the request is for an allowed NFS server and
performs the mount. This now fails because the fc->user_ns is set to the
value in the container and NFS doesn't set FS_USERNS_MOUNT. We don't
want to add FS_USERNS_MOUNT to NFS since that would allow the container
to mount any NFS server (even malicious ones).
Add a new FS_USERNS_DELEGATABLE flag, and enable it on NFS.
Fixes: e1c5ae59c0 ("fs: don't allow non-init s_user_ns for filesystems without FS_USERNS_MOUNT")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260129-twmount-v1-1-4874ed2a15c4@kernel.org
Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
Reviewed-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@futurfusion.io>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Lingfeng identified a bug and suggested two solutions, but both appear
to have issues.
Generally, we cannot release flc_lock while iterating over the file lock
list to avoid use-after-free (UAF) problems with file locks. However,
functions like nfs_delegation_claim_locks and nfs4_reclaim_locks cannot
adhere to this rule because recover_lock or nfs4_lock_delegation_recall
may take a long time. To resolve this, NFS switches to using nfsi->rwsem
for the same protection, and nfs_reclaim_locks follows this approach.
Although nfs_delegation_claim_locks uses so_delegreturn_mutex instead,
this is inadequate since a single inode can have multiple nfs4_state
instances. Therefore, the fix is to also use nfsi->rwsem in this case.
Furthermore, after commit c69899a17c ("NFSv4: Update of VFS byte range
lock must be atomic with the stateid update"), the functions
nfs4_locku_done and nfs4_lock_done also break this rule because they
call locks_lock_inode_wait without holding nfsi->rwsem. Simply adding
this protection could cause many deadlocks, so instead, the call to
locks_lock_inode_wait is moved into _nfs4_proc_setlk. Regarding the bug
fixed by commit c69899a17c ("NFSv4: Update of VFS byte range
lock must be atomic with the stateid update"), it has been resolved
after commit 0460253913 ("NFSv4: nfs4_do_open() is incorrectly triggering
state recovery") because all slots are drained before calling
nfs4_do_reclaim, which prevents concurrent stateid changes along this path.
Also, nfs_delegation_claim_locks does not cause this concurrency either
since when _nfs4_proc_setlk is called with NFS_DELEGATED_STATE, no RPC is
sent, so nfs4_lock_done is not called. Therefore,
nfs4_lock_delegation_recall from nfs_delegation_claim_locks is the first
time the stateid is set.
Reported-by: Li Lingfeng <lilingfeng3@huawei.com>
Closes: https://lore.kernel.org/all/20250419085709.1452492-1-lilingfeng3@huawei.com/
Closes: https://lore.kernel.org/all/20250715030559.2906634-1-lilingfeng3@huawei.com/
Fixes: c69899a17c ("NFSv4: Update of VFS byte range lock must be atomic with the stateid update")
Signed-off-by: Yang Erkun <yangerkun@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Handle -NFS4ERR_OLD_STATEID in nfs4_layoutcommit_done().
This issue was reproduced on NFSv4.2.
Without refreshing data->args.stateid, LAYOUTCOMMIT can keep retrying
with the same stale stateid after OLD_STATEID, resulting in an
unbounded retry loop.
Refresh the layout stateid with nfs4_layout_refresh_old_stateid()
and restart the RPC only after a successful refresh.
Changes since v1: update refreshed stateid in inode layout header.
Signed-off-by: Lei Yin <yinlei2@lenovo.com>
[Anna: Fix up dprintk() format specifier]
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
NFS O_DIRECT reads already (mostly) handle async requests, with the
exception of locking the inode for direct.
Handle async requests properly by using nfs_start_io_direct_nowait,
and then expose FMODE_NOWAIT since it's now supported for direct reads.
Signed-off-by: Dylan Yudaken <dyudaken@gmail.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
nfs_start_io_direct might block on existing operations to the same
inode. In order to support NOWAIT O_DIRECT reads, add a non-blocking
version of this nfs_start_io_direct that just returns -EAGAIN if locks
could not be taken.
Signed-off-by: Dylan Yudaken <dyudaken@gmail.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
The FF_FLAGS_NO_IO_THRU_MDS flag lives on each lseg, so any fallback
decision made when there is no current lseg (e.g. between LAYOUTRETURN
and the next LAYOUTGET) cannot run the per-lseg check.
Introduce a sticky hdr-level ditto for FF_FLAGS_NO_IO_THRU_MDS in
struct nfs4_flexfile_layout::flags (NFS4_FF_HDR_NO_IO_THRU_MDS bit),
set whenever ff_layout_alloc_lseg() parses an lseg with the flag. The
bit is never cleared for the lifetime of the layout hdr; the server is
assumed to be consistent in its no-fallback policy per file.
kzalloc() in ff_layout_alloc_layout_hdr() zero-initializes the field.
Use the new ff_layout_hdr_no_fallback_to_mds() helper to gate
ff_layout_pg_get_mirror_count_write(): when pnfs_update_layout() returns
NULL (e.g. NFS_LAYOUT_BULK_RECALL, pnfs_layout_io_test_failed,
pnfs_layoutgets_blocked) the existing code unconditionally calls
nfs_pageio_reset_write_mds(). This is a source of unwanted WRITE to
MDS. Fix it by checking NFS4_FF_HDR_NO_IO_THRU_MDS bit, and if set
surface -EAGAIN instead; the writepage-side caller (nfs_do_writepage()
for buffered, nfs_direct_write_reschedule() for O_DIRECT) then
redirties the request so writeback retries via pNFS.
Fixes: 260074cd84 ("pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS")
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Commit f06bedfa62 ("pNFS/flexfiles: don't attempt pnfs on fatal DS
errors") teaches ff_layout_{read,write}_pagelist() to return
PNFS_NOT_ATTEMPTED when nfs4_ff_layout_prepare_ds() fails with a
nfs_error_is_fatal() errno (e.g. -ETIMEDOUT from a SOFTCONN connect
deadline, -ENOMEM, -ERESTARTSYS), so that the client gives up instead
of spinning. pnfs_do_{read,write}() then dispatches the I/O through
pnfs_{read,write}_through_mds() → nfs_pageio_reset_{read,write}_mds().
That fallback is unconditional and silently violates FF_FLAGS_NO_IO_THRU_MDS:
when the layout segment carries the flag (typically single-mirror
appliance layouts where MDS I/O is explicitly forbidden), the
out_failed: path's \`&& !ds_fatal_error\` clause overrides the flag's
short-circuit through ff_layout_avoid_mds_available_ds() and routes
the I/O to the MDS file handle anyway.
This is reachable in practice during a data-server restart: SOFTCONN
exhaustion produces -ETIMEDOUT, which is fatal per nfs_error_is_fatal(),
which triggers PNFS_NOT_ATTEMPTED, which silently goes to MDS.
Preserve the upstream "don't spin on fatal errors" intent for layouts
that permit MDS fallback. For layouts with FF_FLAGS_NO_IO_THRU_MDS
set, mark the layout for return and request PNFS_TRY_AGAIN instead;
if the server cannot supply a usable layout the failure now surfaces
cleanly via pnfs_update_layout(), rather than via silent MDS I/O that
contradicts the flag.
Fixes: f06bedfa62 ("pNFS/flexfiles: don't attempt pnfs on fatal DS errors")
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
When a read request is split into multiple subrequests, earlier
completions may advance PG_UPTODATE state for the page group once
their bytes fall within hdr->good_bytes. If a later subrequest in
the same group then completes with NFS_IOHDR_ERROR, the read path
needs to clear any accumulated PG_UPTODATE state and keep later
completions from rebuilding it.
Otherwise, a subsequent successful subrequest can re-enter
nfs_page_group_set_uptodate(), restore the page-group sync state,
and leave stale PG_UPTODATE behind for nfs_page_group_destroy()
to trip over in nfs_free_request().
Add a sticky page-group read-failed flag. Once any subrequest in
the group is known to be bad, mark the group failed, clear any
accumulated PG_UPTODATE state, and refuse further PG_UPTODATE
synchronization for the rest of the completion walk.
Fixes: 67d0338edd ("nfs: page group syncing in read path")
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Sometimes unmounting an NFS filesystem mounted with pNFS SCSI
layouts triggers the following warning:
BUG: scheduling while atomic: umount.nfs4/...
__schedule_bug+0xbd/0x100
schedule_debug.constprop.0+0x19f/0x220
__schedule+0x10d/0x10a0
schedule+0x74/0x190
schedule_timeout+0xf5/0x220
io_schedule_timeout+0xd5/0x160
__wait_for_common+0x186/0x4b0
blk_execute_rq+0x2ef/0x3a0
scsi_execute_cmd+0x1ff/0x700
sd_pr_out_command.isra.0+0x242/0x380 [sd_mod]
bl_unregister_scsi.constprop.0+0x109/0x3c0 [blocklayoutdriver]
bl_unregister_dev+0x175/0x1c0 [blocklayoutdriver]
bl_free_device+0x1f/0x1b0 [blocklayoutdriver]
bl_free_deviceid_node+0x12/0x30 [blocklayoutdriver]
nfs4_put_deviceid_node+0x171/0x360 [nfsv4]
ext_tree_remove+0x11c/0x1d0 [blocklayoutdriver]
_pnfs_return_layout+0x416/0x900 [nfsv4]
nfs4_evict_inode+0x108/0x130 [nfsv4]
evict+0x316/0x750
dispose_list+0xf1/0x1a0
evict_inodes+0x33f/0x440
generic_shutdown_super+0xc9/0x4e0
kill_anon_super+0x3a/0x90
nfs_kill_super+0x44/0x60 [nfs]
deactivate_locked_super+0xb8/0x1b0
cleanup_mnt+0x25a/0x380
task_work_run+0x13e/0x210
exit_to_user_mode_loop+0x169/0x400
do_syscall_64+0x467/0x1550
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The warning occurs because the block layout driver unregisters the SCSI
device while the inode lock is still held. Device unregistration issues
a SCSI PR command, which may sleep, resulting in a "scheduling while
atomic" warning.
During layout return, ext_tree_remove() invokes the layout driver's
return_range callback while holding the inode lock. For block layouts,
this callback eventually calls bl_unregister_scsi(), which may block in
scsi_execute_cmd() while issuing PR commands to the device.
Fix this by deferring the return_range callbacks until after the inode
lock has been released. The layout header reference count is incremented
before invoking return_range(), ensuring that the layout header remains
valid while the layout driver removes extents from the extent tree.
Fixes: c88953d87f ("pnfs: add return_range method")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
When hitting the NFS_LAYOUT_RETURN branch in pnfs_update_layout(),
the code calls pnfs_prepare_to_retry_layoutget(lo). If it succeeds,
pnfs_put_layout_hdr(lo) is called before trace_pnfs_update_layout(),
which still references 'lo'. This results in a use-after-free when the
tracepoint accesses lo's fields.
Fix this by moving the tracepoint call before pnfs_put_layout_hdr(lo).
Fixes: 2c8d5fc37f ("pNFS: Stricter ordering of layoutget and layoutreturn")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Generic/075 reliably exposes a regression when the client holds an
NFSv4 write delegation: ZERO_RANGE/ALLOCATE extends the file on the
server, but the local inode keeps the old i_size. The test then fails
with 'Size error' because the post-op attribute refresh refuses to
touch i_size while a delegation is outstanding, and the cached EOF
was never marked stale.
Update _nfs42_proc_fallocate() so that on success it:
- bumps i_size when the operation extends the file, and
- marks NFS_INO_INVALID_BLOCKS since the block count can also change
Tested with xfstests generic/075 over NFSv4.2.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
mount output should not reveal the contents of the serials, but indicate
they were provided.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
A layout can still be striped with num_fh = 1 as it is perfectly possible
that both MDS and DSs can handle the same filehandle. Hence check according
to stripe_count > 1, which is the correct check to begin with.
We should not be called with flseg->dsaddr = NULL, but if for some reason
we do, return our best guess with is flseg->num_fh > 1.
Fixes: a6b9d2fa00 ("pNFS/filelayout: Fix coalescing test for single DS")
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
After a server returns NFS4ERR_DELAY for an NFSv4 CREATE issued by
mkdir(2), the client correctly waits and retries. When the retry
succeeds, however, mkdir(2) can still surface -EEXIST to userspace
even though the directory was just created on the server.
Reproducer (random 16-hex names so collisions are not the cause)
against an in-kernel Linux nfsd; reproduces under both NFSv4.0 and
NFSv4.2:
N=2000000; base=/var/gdc/export
for ((i=1; i<=N; i++)); do
d=$base/$(openssl rand -hex 8)
mkdir "$d" 2>/dev/null || echo "$(date +%T) failed loop=$i $d"
rmdir "$d" 2>/dev/null
done
Failures cluster at the cadence at which the server-side auth/export
cache refresh path causes nfsd to return NFS4ERR_DELAY for CREATE.
A wire trace of one failure (the three CREATE RPCs all come from a
single mkdir(2), generated by the do-while in nfs4_proc_mkdir()):
client -> server CREATE name=... -> NFS4ERR_DELAY
~100 ms later
client -> server CREATE name=... -> NFS4_OK (dir created)
~80 us later
client -> server CREATE name=... -> NFS4ERR_EXIST (correct)
Since commit dd862da61e ("nfs: fix incorrect handling of large-number
NFS errors in nfs4_do_mkdir()"), nfs4_handle_exception() is called only
when _nfs4_proc_mkdir() returned an error. That gate breaks retry-state
hygiene: nfs4_do_handle_exception() resets exception.{delay,recovering,
retry} to 0 on entry, so calling it on success is what previously
cleared the retry flag set by the preceding NFS4ERR_DELAY iteration.
With the gate in place, exception.retry stays at 1 after the successful
retry, the loop runs once more, and the resulting CREATE for an
already-created name yields NFS4ERR_EXIST -> -EEXIST to userspace.
Drop the conditional and call nfs4_handle_exception() unconditionally,
matching every other do-while in fs/nfs/nfs4proc.c (nfs4_proc_symlink(),
nfs4_proc_link(), etc.). The dentry/status separation introduced by
that commit is preserved.
Fixes: dd862da61e ("nfs: fix incorrect handling of large-number NFS errors in nfs4_do_mkdir()")
Reported-and-tested-by: Jan Čípa <jan.cipa@gooddata.com>
Closes: https://lore.kernel.org/linux-nfs/CA+9S74hSp_tJu2Ffe2BPNC2T25gfkhgjjDkdgSsF5c2rnJq_wA@mail.gmail.com/
Reviewed-by: NeilBrown <neil@brown.name>
Cc: stable@vger.kernel.org
Signed-off-by: Igor Raits <igor.raits@gmail.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
ff_layout_alloc_lseg() decodes the filehandle-version array count
from the flexfiles layout body. The value is used as the count for
kzalloc_objs(), and the current code only rejects NULL.
A zero count yields ZERO_SIZE_PTR, which can be stored in
dss_info->fh_versions even though later flexfiles paths assume that at
least one filehandle version exists.
Reject fh_count == 0 before the allocation, matching the existing zero
version_count validation in the flexfiles GETDEVICEINFO parser.
A QEMU/KASAN run with a malformed flexfiles layout hit:
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
RIP: 0010:ff_layout_encode_ff_layoutupdate.isra.0+0x15f/0x750
ff_layout_encode_layoutreturn+0x683/0x970
nfs4_xdr_enc_layoutreturn+0x278/0x3a0
Kernel panic - not syncing: Fatal exception
The patched kernel rejects the malformed layout without KASAN/oops/panic,
and a valid fh_count=1 regression still opens, reads, and unmounts cleanly.
Cc: stable@vger.kernel.org
Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Now that inode->i_ino stores the full 64-bit NFS fileid, replace all
uses of NFS_FILEID(), set_nfs_fileid(), and direct nfsi->fileid
accesses with inode->i_ino throughout the NFS client.
Remove the NFS_FILEID() and set_nfs_fileid() helper functions from
include/linux/nfs_fs.h since they are no longer needed.
Also fix two pre-existing truncation bugs in nfs4trace.h where fileid
trace fields were declared as u32 instead of u64.
Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Now that inode->i_ino stores the full 64-bit NFS fileid, the
nfs_compat_user_ino64() function is no longer needed.
generic_fillattr() already copies inode->i_ino into stat->ino, so the
explicit override in nfs_getattr() is also redundant.
Also remove the now-unused nfs_fileid_to_ino_t() and
nfs_fattr_to_ino_t() helper functions that were used to XOR-fold
64-bit fileids into the old unsigned long i_ino.
Keep the enable_ino64 module parameter as a deprecated stub that
accepts but ignores the value, logging a notice when set. This avoids
breaking existing configurations that pass nfs.enable_ino64 on the
kernel command line or in modprobe.d.
Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Now that inode->i_ino is a 64-bit value, store the full NFS fileid in
it directly instead of an XOR-folded hash. This makes NFS_FILEID() and
set_nfs_fileid() operate on inode->i_ino rather than the separate
nfsi->fileid field.
Since iget5_locked() and ilookup5() now accept a u64 hashval, pass the
full fileid as the hash parameter directly.
Convert direct nfsi->fileid accesses in nfs_check_inode_attributes(),
nfs_update_inode(), and nfs_same_file() to use inode->i_ino.
Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
... just grab the reference to the (real) root we are about to return
for the first mount of this superblock and be done with that.
Once upon a time dentry tree eviction at fs shutdown used to break
if ->s_root had been spliced on top of something; that hadn't been
the case for years now, and these fake root dentries violate a bunch
of invariants. Let's get rid of them...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Parallel lookup starts with a call of d_alloc_parallel(). That primitive
either returns a matching hashed dentry or allocates a new one in the
in-lookup state and returns it to the caller. Once the caller is done
with lookup, it indicates so either by call of d_{splice_alias,add}()
or by call of d_done_lookup(); at that point dentry leaves the in-lookup
state.
If d_alloc_parallel() finds a matching in-lookup dentry, it must wait for
that dentry to leave the in-lookup state, one way or another. Currently
by supplying wait_queue_head to d_alloc_parallel(). If d_alloc_parallel()
creates a new in-lookup dentry, the address of that wait_queue_head is stored
in ->d_wait of new dentry and stays there while it's in the in-lookup;
subsequent d_alloc_parallel() will wait on the queue found in the matching
in-lookup dentry. Transition out of in-lookup state wakes waiters on that
queue (if any).
That works, but the calling conventions are inconvenient - the caller must
supply wait_queue_head and make sure that it survives at least until the new
in-lookup dentry leaves the in-lookup state. That amounts to boilerplate
in the d_alloc_parallel() callers that are followed by a call of d_lookup_done()
in the same function; in cases like nfs asynchronous unlink it gets worse than
that.
This patch changes d_alloc_parallel() to use wake_up_var_locked() to
wake up waiters, and wait_var_event_spinlock() to wait. dentry->d_lock
is used for synchronisation as it is already held and the relevant
times.
That eliminates the need of caller-supplied wait_queue_head, simplifying
the calling conventions. Better yet, we only need one bit of information
stored in dentry itself: whether there are any waiters to be woken up,
and that can be easily stored in ->d_flags; ->d_wait goes away.
The reason we need that bit (DCACHE_LOOKUP_WAITERS) is that with wait_var
machinery the queues are shared with all kinds of stuff and there's
no way tell if any of the waiters have anything to do with our dentry;
most of the time none of them will be relevant, so we need to avoid the
pointless wakeups.
Another benefit of the new scheme comes from the fact that wakeups
have to be done outside of write-side critical areas of ->i_dir_seq;
with the old scheme we need to carry the value picked from ->d_wait from
__d_lookup_unhash() to the place where we actually wake the waiters up.
Now we can just leave DCACHE_LOOKUP_WAITERS in ->d_flags until we get
to doing wakeups - that's done within the same ->d_lock scope, so we
are fine; new bit is accessed only under ->d_lock and it's seen only
on dentries with DCACHE_PAR_LOOKUP in ->d_flags.
__d_lookup_unhash() no longer needs to re-init ->d_lru. That was
previously shared (in a union) with ->d_wait but ->d_wait is now gone
so it no longer corrupts ->d_lru.
Co-developed-by: Al Viro <viro@zeniv.linux.org.uk> # saner handling of flags
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
5d3869a41f ("NFS: fix writeback in presence of errors") introduced
a dereference of hdr->req->wb_lock_context in nfs_write_completion's
per-request loop. hdr->req is set once at nfs_pgheader_init() time
and is not refcount-protected for the lifetime of the loop; when hdr
aggregates requests from multiple page groups (common under heavy
NFSv3 writeback), a parallel COMMIT on hdr->req's group can drop the
last reference and free it while the outer loop is still iterating
requests from other groups. KASAN catches this as an 8-byte read at
offset +24 of a freed nfs_page slab object (wb_lock_context).
All requests in a given pgio share the same open_context, so reading
the loop-local req's wb_lock_context yields the same value and is
safe -- req is still on hdr->pages and holds its writeback kref
through the commit branch.
Caught with kasan:
BUG: KASAN: slab-use-after-free in nfs_write_completion+0x8f8/0xa50 [nfs]
Read of size 8 at addr ffff888118af2058 by task kworker/u16:16/122062
CPU: 2 UID: 0 PID: 122062 Comm: kworker/u16:16 Kdump: loaded Not tainted 7.1.0-rc4+ #ge05a759574b2 PREEMPT
Workqueue: nfsiod rpc_async_release
Call Trace:
<TASK>
dump_stack_lvl+0xaf/0x100
? nfs_write_completion+0x8f8/0xa50 [nfs]
print_report+0x157/0x4a1
? __virt_addr_valid+0x1fb/0x400
? nfs_write_completion+0x8f8/0xa50 [nfs]
kasan_report+0xc2/0x190
? nfs_write_completion+0x8f8/0xa50 [nfs]
nfs_write_completion+0x8f8/0xa50 [nfs]
? nfs_commit_release_pages+0xbd0/0xbd0 [nfs]
? lock_acquire+0x182/0x2e0
? process_one_work+0x937/0x1890
? nfs_pgio_header_alloc+0xd0/0xd0 [nfs]
rpc_free_task+0xee/0x160
rpc_async_release+0x5d/0xb0
process_one_work+0x9b0/0x1890
? pwq_dec_nr_in_flight+0xed0/0xed0
? rpc_final_put_task+0x140/0x140
worker_thread+0x75a/0x10a0
? process_one_work+0x1890/0x1890
? kthread+0x1af/0x4d0
? process_one_work+0x1890/0x1890
kthread+0x3d3/0x4d0
? kthread_affine_node+0x2c0/0x2c0
ret_from_fork+0x669/0xa50
? native_tss_update_io_bitmap+0x660/0x660
? __switch_to+0x9dd/0x1310
? kthread_affine_node+0x2c0/0x2c0
ret_from_fork_asm+0x11/0x20
</TASK>
Allocated by task 121997 on cpu 3 at 31643.290294s:
kasan_save_stack+0x1e/0x40
kasan_save_track+0x13/0x60
__kasan_slab_alloc+0x62/0x70
kmem_cache_alloc_noprof+0x1ab/0x4e0
nfs_page_create+0x152/0x460 [nfs]
nfs_page_create_from_folio+0x7e/0x210 [nfs]
nfs_update_folio+0x7a9/0x32a0 [nfs]
nfs_write_end+0x290/0xc60 [nfs]
generic_perform_write+0x4ce/0x990
nfs_file_write+0x6b3/0xce0 [nfs]
vfs_write+0x63c/0xfa0
ksys_write+0x122/0x240
do_syscall_64+0xc3/0x13f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Freed by task 122046 on cpu 0 at 31647.037964s:
kasan_save_stack+0x1e/0x40
kasan_save_track+0x13/0x60
kasan_save_free_info+0x37/0x60
__kasan_slab_free+0x3b/0x60
kmem_cache_free+0x11b/0x5a0
nfs_page_group_destroy+0x13a/0x210 [nfs]
nfs_unlock_and_release_request+0x64/0x90 [nfs]
nfs_commit_release_pages+0x339/0xbd0 [nfs]
nfs_commit_release+0x51/0xb0 [nfs]
rpc_free_task+0xee/0x160
rpc_async_release+0x5d/0xb0
process_one_work+0x9b0/0x1890
worker_thread+0x75a/0x10a0
kthread+0x3d3/0x4d0
ret_from_fork+0x669/0xa50
ret_from_fork_asm+0x11/0x20
The buggy address belongs to the object at ffff888118af2040\x0a which belongs to the cache nfs_page of size 96
The buggy address is located 24 bytes inside of\x0a freed 96-byte region [ffff888118af2040, ffff888118af20a0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x118af2
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x4000000000000040(head|zone=2)
page_type: f5(slab)
raw: 4000000000000040 ffff88818cf2c4c0 ffffea000e61b990 ffffea0004e7d110
raw: 0000000000000000 0000000800190019 00000000f5000000 0000000000000000
head: 4000000000000040 ffff88818cf2c4c0 ffffea000e61b990 ffffea0004e7d110
head: 0000000000000000 0000000800190019 00000000f5000000 0000000000000000
head: 4000000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 121997, tgid 121997 (rsync), ts 31643290274577, free_ts 31642154777182
post_alloc_hook+0xd1/0x100
get_page_from_freelist+0xbad/0x2910
__alloc_frozen_pages_noprof+0x1c6/0x4a0
allocate_slab+0x330/0x620
___slab_alloc+0xe9/0x930
kmem_cache_alloc_noprof+0x35b/0x4e0
nfs_page_create+0x152/0x460 [nfs]
nfs_page_create_from_folio+0x7e/0x210 [nfs]
nfs_update_folio+0x7a9/0x32a0 [nfs]
nfs_write_end+0x290/0xc60 [nfs]
generic_perform_write+0x4ce/0x990
nfs_file_write+0x6b3/0xce0 [nfs]
vfs_write+0x63c/0xfa0
ksys_write+0x122/0x240
do_syscall_64+0xc3/0x13f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
page last free pid 122202 tgid 122202 stack trace:
__free_frozen_pages+0x6da/0xf30
qlist_free_all+0x53/0x130
kasan_quarantine_reduce+0x198/0x1f0
__kasan_slab_alloc+0x46/0x70
kmem_cache_alloc_noprof+0x1ab/0x4e0
__alloc_object+0x2f/0x230
__create_object+0x22/0x80
kmem_cache_alloc_node_noprof+0x416/0x4d0
__alloc_skb+0x146/0x6e0
tcp_stream_alloc_skb+0x35/0x660
tcp_sendmsg_locked+0x1746/0x4260
tcp_sendmsg+0x2f/0x40
inet_sendmsg+0x9e/0xe0
__sock_sendmsg+0xd9/0x180
sock_sendmsg+0x122/0x200
xprt_sock_sendmsg+0x4ff/0x9a0
Memory state around the buggy address:
ffff888118af1f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc
ffff888118af1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888118af2000: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
^
ffff888118af2080: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
ffff888118af2100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Reviewed-by Jeff Layton <jlayton@kernel.org>
Fixes: 5d3869a41f ("NFS: fix writeback in presence of errors")
Cc: Olga Kornievskaia <okorniev@redhat.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: linux-nfs@vger.kernel.org
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This function doesn't have anything to do with a timeout. The only
difference is that it warns if there are no listeners. Rename it to
sunrpc_cache_upcall_warn().
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Temporary buffers page and page2 allocated by nfs4_replace_transport() and
passed to nfs4_try_replacing_one_location() are never used.
Remove them and the code that allocates and frees memory for these buffers.
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Link: https://patch.msgid.link/20260523-b4-fs-v1-6-275e36a83f0e@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
nfs_show_devname() allocates a tmemporary buffer __get_free_page().
kmalloc() is a better API for such use and it also provides better
scalability and more debugging possibilities.
Replace use of __get_free_page() with kmalloc().
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Link: https://patch.msgid.link/20260523-b4-fs-v1-5-275e36a83f0e@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
This flag indicates the path should be opened if it's a regular file.
This is useful to write secure programs that want to avoid being
tricked into opening device nodes with special semantics while thinking
they operate on regular files. This is a requested feature from the
uapi-group[1].
The previously introduced EFTYPE error code is returned when the path
doesn't refer to a regular file. For example, if openat2 is called on
path /dev/null with OPENAT2_REGULAR in the flag param, it will return
-EFTYPE.
When used in combination with O_CREAT, either the regular file is
created, or if the path already exists, it is opened if it's a regular
file. Otherwise, -EFTYPE is returned.
When OPENAT2_REGULAR is combined with O_DIRECTORY, -EINVAL is returned
as it doesn't make sense to open a path that is both a directory and a
regular file.
The UAPI bit lives in the upper 32 bits of open_how::flags
(((__u64)1 << 32)) so that open(2) and openat(2) -- whose @flags
argument is a C int -- cannot physically express it. This is a
structural guarantee, not a runtime mask: the bit is unrepresentable in
32 bits.
Because the rest of the VFS open path narrows to 32 bits in several
places (op->open_flag, f->f_flags, the unsigned open_flag argument of
i_op->atomic_open()), build_open_flags() translates OPENAT2_REGULAR
into a kernel-internal lower-32-bit carrier __O_REGULAR (bit 4, unused
as an O_* on every architecture) before the assignment to op->open_flag.
__O_REGULAR then rides through the existing channels exactly like
__FMODE_EXEC. do_dentry_open() strips it so it cannot leak back to
userspace via fcntl(F_GETFL).
Four BUILD_BUG_ON_MSG() invariants in build_open_flags() prevent any
future bit collision or accidental low-32 redefinition:
- VALID_OPEN_FLAGS fits in 32 bits.
- OPENAT2_REGULAR lives in the upper 32 bits.
- OPENAT2_REGULAR does not alias any open()/openat() flag.
- __O_REGULAR does not alias any user-visible flag.
[1]: https://uapi-group.org/kernel-features/#ability-to-only-open-regular-files
Christian Brauner <brauner@kernel.org> says:
Move OPENAT2_REGULAR to the upper 32 bits of open_how::flags with a
kernel-internal __O_REGULAR carrier so that open(2)/openat(2) cannot
encode the flag; add BUILD_BUG_ON_MSG() invariants and register
__O_REGULAR in the fcntl_init() allocation-uniqueness BUILD_BUG_ON()
(bit count 21 -> 22).
Signed-off-by: Dorjoy Chowdhury <dorjoychy111@gmail.com>
Link: https://patch.msgid.link/20260328172314.45807-2-dorjoychy111@gmail.com
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Aleksa Sarai <aleksa@amutable.com>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
The PATHCONF RPC issued from nfs_probe_fsinfo() supplies two pieces of
information: max_namelen, used only when server->namelen has not been
pinned by mount options, and the case_insensitive / case_preserving
fields, used only by the NFSv2/NFSv3 path. NFSv4 receives its case
sensitivity caps from the FATTR4_CASE_* attributes during the
set_capabilities probe, and a non-zero server->namelen short-circuits
the only other field of interest.
When both conditions hold (NFSv4 with namelen pinned), the pathconf
reply is discarded in full but the round-trip is still on the mount
critical path. Gate the call on version < 4 || namelen == 0 so that
mounts which cannot benefit from the reply do not pay for it.
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260507-case-sensitivity-v14-0-e62cc8200435@oracle.com?part=10
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://patch.msgid.link/20260515153515.362266-4-cel@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
nfs_probe_fsinfo() clears NFS_CAP_CASE_INSENSITIVE and
NFS_CAP_CASE_NONPRESERVING ahead of the synchronous pathconf RPC and
sets them again only after the reply arrives. The code path is gated
by clp->rpc_ops->version < 4 and is therefore reached on NFSv2/v3
remount via nfs_reconfigure(), which calls nfs_probe_server() against
a live mount. Concurrent readers walking server->caps can observe the
cleared state for the duration of the round-trip and report the wrong
case-sensitivity attributes.
Compute the post-probe capability mask on the stack and assign it to
server->caps in a single store so readers see either the stale value
or the freshly computed one, never an intermediate zero. Preserve the
original behaviour of dropping the bits when the pathconf RPC itself
fails.
The analogous transient zero on the NFSv4 path lives in
nfs4_server_capabilities() and is left for a separate fix.
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260507-case-sensitivity-v14-0-e62cc8200435@oracle.com?part=10
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://patch.msgid.link/20260515153515.362266-3-cel@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
An NFS server re-exporting an NFS mount point needs to report
the case sensitivity behavior of the underlying filesystem to
its clients. NFSD's attribute encoder obtains that information
by calling vfs_fileattr_get() on the lower filesystem, so the
NFS client must implement fileattr_get to surface what it
learned from its own server.
The NFS client already retrieves case sensitivity information
from servers during mount via PATHCONF (NFSv3) or the
FATTR4_CASE_INSENSITIVE/FATTR4_CASE_PRESERVING attributes
(NFSv4). Expose this information through fileattr_get by
reporting the FS_XFLAG_CASEFOLD and FS_XFLAG_CASENONPRESERVING
flags. NFSv2 lacks PATHCONF support, so mounts using that protocol
version default to standard POSIX behavior: case-sensitive and
case-preserving.
PATHCONF is now invoked unconditionally for NFSv2 and NFSv3 mounts
so the case-sensitivity capabilities are established even when the
user pins server->namelen with the namlen= mount option. That option
is orthogonal to case handling, and skipping PATHCONF because
namelen was already known would leave the caps unset.
The two capability bits carry opposite polarity because their POSIX
defaults differ. Most servers are case-sensitive and case-
preserving, matching "neither xflag set." NFS_CAP_CASE_INSENSITIVE
is set only when the server affirms case insensitivity, so "server
said no" and "server did not answer" both collapse to the case-
sensitive default. NFS_CAP_CASE_NONPRESERVING follows the same
pattern in the opposite direction: set only when the server affirms
that it does not preserve case, so that silence or a missing
attribute lands on the case-preserving default. The NFSv4 probe
checks res.attr_bitmask[0] to distinguish "server said false" from
"server omitted the attribute" before setting the bit.
Both capability bits are cleared before each probe so a remount,
an NFSv4 transparent state migration to a server with different
case semantics, or a probe whose reply does not arrive does not
retain stale capabilities from the prior probe.
Reviewed-by: Roland Mainz <roland.mainz@nrubsig.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://patch.msgid.link/20260507-case-sensitivity-v14-10-e62cc8200435@oracle.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pull NFS client updates from Trond Myklebust:
"Bugfixes:
- Fix handling of ENOSPC so that if we have to resend writes, they
are written synchronously
- SUNRPC RDMA transport fixes from Chuck
- Several fixes for delegated timestamps in NFSv4.2
- Failure to obtain a directory delegation should not cause stat() to
fail with NFSv4
- Rename was failing to update timestamps when a directory delegation
is held on NFSv4
- Ensure we check rsize/wsize after crossing a NFSv4 filesystem
boundary
- NFSv4/pnfs:
- If the server is down, retry the layout returns on reboot
- Fallback to MDS could result in a short write being incorrectly
logged
Cleanups:
- Use memcpy_and_pad in decode_fh"
* tag 'nfs-for-7.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (21 commits)
NFS: Fix RCU dereference of cl_xprt in nfs_compare_super_address
NFS: remove redundant __private attribute from nfs_page_class
NFSv4.2: fix CLONE/COPY attrs in presence of delegated attributes
NFS: fix writeback in presence of errors
nfs: use memcpy_and_pad in decode_fh
NFSv4.1: Apply session size limits on clone path
NFSv4: retry GETATTR if GET_DIR_DELEGATION failed
NFS: fix RENAME attr in presence of directory delegations
pnfs/flexfiles: validate ds_versions_cnt is non-zero
NFS/blocklayout: print each device used for SCSI layouts
xprtrdma: Post receive buffers after RPC completion
xprtrdma: Scale receive batch size with credit window
xprtrdma: Replace rpcrdma_mr_seg with xdr_buf cursor
xprtrdma: Decouple frwr_wp_create from frwr_map
xprtrdma: Close lost-wakeup race in xprt_rdma_alloc_slot
xprtrdma: Avoid 250 ms delay on backlog wakeup
xprtrdma: Close sendctx get/put race that can block a transport
nfs: update inode ctime after removexattr operation
nfs: fix utimensat() for atime with delegated timestamps
NFS: improve "Server wrote zero bytes" error
...
The cl_xprt pointer in struct rpc_clnt is marked as __rcu. Accessing
it directly in nfs_compare_super_address() is unsafe and triggers
Sparse warnings.
Fix this by using rcu_dereference() within an RCU read-side critical
section to retrieve the transport pointer. This addresses the sparse
warning and ensures atomic access to the pointer, as the transport
can be updated via transport switching even while the superblock
remains active under sb_lock.
Fixes: 7e3fcf61ab ("nfs: don't share mounts between network namespaces")
Signed-off-by: Sean Chang <seanwascoding@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The nfs_page_class tracepoint uses a pointer for the 'req' field marked
with the __private attribute. This causes Sparse to complain about
dereferencing a private pointer within the trace ring buffer context,
specifically during the TP_fast_assign() operation.
This fixes a Sparse warning introduced in commit b6ef079fd9 ("nfs:
more in-depth tracing of writepage events") by removing the redundant
__private attribute from the 'req' field.
Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com>
Signed-off-by: Sean Chang <seanwascoding@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
xfstest generic/407 is failing in 2 ways. It detects that after
doing a clone the client does not update it's mtime and it's ctime.
CLONE always sends a GETATTR operation and then calls
nfs_post_op_update_inode() based on the returned attributes.
Because of the delegated attributes the client ignores updating
the mtime. Then also, when delegated attributes are present, for
the change_attr the server replies with the same values as what
the client cached before and thus the generic/407 would flag that.
Instead, make sure we invalidate the blocks attr.
By adding updating delegated attributes in nfs42_copy_dest_done()
both COPY and CLONE would update mtime appropriately.
Fixes: e12912d941 ("NFSv4: Add support for delegated atime and mtime attributes")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
After running xfstest generic/751, in certain conditions, can have
a writeback IO stuck while experiencing one of the two patterns.
Pattern#1: writeback IO experiences ENOSPC on an offset smaller
than the filesize. Example,
write offset=0 len=4096 how=unstable OK
write offset=8192 len=4096 how=unstable OK
write offset=12288 len=4096 how=unstable ENOSPC
write offset=4096 len=4096 how=unstable ENOSPC
client sends a commit and receives a verifier which is different
from the last successful write. It marks pages dirty and writeback
retries. But it again send writes unstable and gets into the same
pattern, running into the ENOSPC error and sending a commit because
writes were sent at unstable.
Pattern#2: an unstable write followed by a short write and ENOSPC.
write offset=0 len=4096 how=unstable OK
write offset=4096 len=4096 how=unstable returns OK but count=100
write offset=4197 len=3996 how=stable returns ENOSPC
client send a commit and receives a verifier different from
the last unstable write. The same behaviour is retried in a loop.
Instead, this patch proposes to identify those conditions and mark
requests to be done synchronously instead. Previous solution tried
to mark it in the nfs_page, however that's not persistent thus
instead mark it in the nfs_open_context.
Furthermore, the same problem occurs during localio code path so
recognize that IO needs to be done sync in that case as well.
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Pull dcache busy loop updates from Al Viro:
"Fix livelocks in shrink_dcache_tree()
If shrink_dcache_tree() finds a dentry in the middle of being killed
by another thread, it has to wait until the victim finishes dying,
gets detached from the tree and ceases to pin its parent.
The way we used to deal with that amounted to busy-wait;
unfortunately, it's not just inefficient but can lead to reliably
reproducible hard livelocks.
Solved by having shrink_dentry_tree() attach a completion to such
dentry, with dentry_unlist() calling complete() on all objects
attached to it. With a bit of care it can be done without growing
struct dentry or adding overhead in normal case"
* tag 'pull-dcache-busy-wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
get rid of busy-waiting in shrink_dcache_tree()
dcache.c: more idiomatic "positives are not allowed" sanity checks
struct dentry: make ->d_u anonymous
for_each_alias(): helper macro for iterating through dentries of given inode
Linus Torvalds
Markus Elfring
Michael Bommarito
Tom Haynes
Ethan Nelson-Moore
Jeff Layton
Yang Erkun
Lei Yin
Dylan Yudaken
Mike Snitzer
Clark Wang
Dai Ngo
Wentao Liang
Sagi Grimberg
Igor Raits
Al Viro
NeilBrown
Dave Jones
Mike Rapoport (Microsoft)
Dorjoy Chowdhury
Chuck Lever
Mateusz Guzik
Stephen Smalley
Sean Chang
Olga Kornievskaia
Thorsten Blum