Clang compiler is not happy about set but unused variable
(when dprintk() is no-op):
.../blocklayout/blocklayout.c:384:9: error: variable 'count' set but not used [-Werror,-Wunused-but-set-variable]
Remove a leftover from the previous cleanup.
Fixes: 3a6fd1f004 ("pnfs/blocklayout: remove read-modify-write handling in bl_write_pagelist")
Acked-by: Anna Schumaker <anna.schumkaer@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Public RPC server interfaces become cluttered when internal
XDR implementation details leak into them. The procedure count,
maximum XDR buffer size, and per-CPU call counters serve no
purpose outside the code that encodes and decodes NLM protocol
messages. Exposing these values through global headers creates
unnecessary coupling between the RPC dispatch logic and the
XDR layer.
Relocating the svc_version structure definitions confines this
implementation information to the files where XDR encoding and
decoding occur. In svc.c, the buffer size computation now reads
vs_xdrsize from the version structures rather than relying on a
preprocessor constant. This calculation occurs at service
initialization, after the linker has resolved the version
structure definitions. The dispatch function becomes non-static
because both the version structures and the dispatcher reside in
different translation units.
The NLMSVC_XDRSIZE macro is removed from xdr.h because buffer
size is now computed from the union of XDR argument and result
structures, matching the pattern used in other RPC services.
Version 1 and 3 share the same procedure table but maintain
separate counter arrays. Version 4 remains separate due to its
distinct procedure definitions.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Both client-side and server-side NLMv4 code convert lock byte ranges
from the wire format (start, length) to the kernel's file_lock format
(start, end). The current nlm4svc_set_file_lock_range() performs this
conversion, but the "svc" prefix incorrectly suggests server-only use,
and client code must include server-internal headers to access it.
Rename to lockd_set_file_lock_range4() and relocate to the shared
lockd.h header, making it accessible to both client and server code.
This eliminates the need for client code to include xdr4.h, reducing
coupling between the XDR implementation files.
While relocating the function, add input validation: clamp the
starting offset to OFFSET_MAX before use. Without this, a malformed
lock request with off > OFFSET_MAX results in fl_start > fl_end,
violating file_lock invariants and potentially causing incorrect
lock conflict detection.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The NLM protocol constants and status codes in nlm.h are needed
only by lockd's internal implementation. NFS client code and
NFSD interact with lockd through the stable API in bind.h and
have no direct use for protocol-level definitions.
Exposing these definitions globally via bind.h creates unnecessary
coupling between lockd internals and its consumers. Moving nlm.h
from include/linux/lockd/ to fs/lockd/ clarifies the API boundary:
bind.h provides the lockd service interface, while nlm.h remains
available only to code within fs/lockd/ that implements the
protocol.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The lockd subsystem unnecessarily exposes internal NLM XDR type
definitions through the global include path. These definitions
are not used by any code outside fs/lockd/, making them
inappropriate for include/linux/lockd/.
Moving xdr.h to fs/lockd/ narrows the API surface and clarifies
that these types are internal implementation details. The
comment in linux/lockd/bind.h stating xdr.h was needed for
"xdr-encoded error codes" is stale: no lockd API consumers use
those codes.
Forward declarations for struct nfs_fh and struct file_lock are
added to bind.h because their definitions were previously pulled
in transitively through xdr.h. Additionally, nfs3proc.c and
proc.c need explicit includes of filelock.h for FL_CLOSE and
for accessing struct file_lock members, respectively.
Built and tested with lockd client/server operations. No
functional change.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The lockd include structure has unnecessary indirection. The header
include/linux/lockd/debug.h is consumed only by fs/lockd/lockd.h,
creating an extra compilation dependency and making the code harder
to navigate.
Fold the debug.h definitions directly into lockd.h and remove the
now-redundant header. This reduces the include tree depth and makes
the debug-related definitions easier to find when working on lockd
internals.
Build-tested with lockd built as module and built-in.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Headers placed in include/linux/ form part of the kernel's
internal API and signal to subsystem maintainers that other
parts of the kernel may depend on them. By moving lockd.h
into fs/lockd/, lockd becomes a more self-contained module
whose internal interfaces are clearly distinguished from its
public contract with the rest of the kernel. This relocation
addresses a long-standing XXX comment in the header itself
that acknowledged the file's misplacement. Future changes to
lockd internals can now proceed with confidence that external
consumers are not inadvertently coupled to implementation
details.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The share.h header defines struct nlm_share and declares the DOS
share management functions used by the NLM server to implement
NLM_SHARE and NLM_UNSHARE operations. These interfaces are used
exclusively within the lockd subsystem. A git grep search confirms
no external code references them.
Relocating this header from include/linux/lockd/ to fs/lockd/
narrows the public API surface of the lockd module. Out-of-tree
code cannot depend on these internal interfaces after this change.
Future refactoring of the share management implementation thus
requires no consideration of external consumers.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The xdr4.h header declares NLMv4-specific XDR encoder/decoder
functions and error codes that are used exclusively within the
lockd subsystem. Moving it from include/linux/lockd/ to fs/lockd/
clarifies the intended scope of these declarations and prevents
external code from depending on lockd-internal interfaces.
This change reduces the public API surface of the lockd module
and makes it easier to refactor NLMv4 internals without risk of
breaking out-of-tree consumers. The header's contents are
implementation details of the NLMv4 wire protocol handling, not
a contract with other kernel subsystems.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
A race condition exists in shutdown_store() when writing to the sysfs
"shutdown" file concurrently with nlm_shutdown_hosts_net(). Without
synchronization, the following sequence can occur:
1. shutdown_store() reads server->nlm_host (non-NULL)
2. nlm_shutdown_hosts_net() acquires nlm_host_mutex, calls
rpc_shutdown_client(), sets h_rpcclnt to NULL, and potentially
frees the host via nlm_gc_hosts()
3. shutdown_store() dereferences the now-stale or freed host
Introduce nlmclnt_shutdown_rpc_clnt(), which acquires nlm_host_mutex
before accessing h_rpcclnt. This synchronizes with
nlm_shutdown_hosts_net() and ensures the rpc_clnt pointer remains
valid during the shutdown operation.
This change also improves API layering: NFS client code no longer
needs to include the internal lockd header to access nlm_host fields.
The new helper resides in bind.h alongside other public lockd
interfaces.
Reported-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The nlmsvc_unlock_all_by_sb() and nlmsvc_unlock_all_by_ip()
functions are part of lockd's external API, consumed by other
kernel subsystems. Their declarations currently reside in
linux/lockd/lockd.h alongside internal implementation details,
which blurs the boundary between lockd's public interface and
its private internals.
Moving these declarations to linux/lockd/bind.h groups them
with other external API functions and makes the separation
explicit. This clarifies which functions are intended for
external use and reduces the risk of internal implementation
details leaking into the public API surface.
Build-tested with allyesconfig; no functional changes.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The nlm_fopen() function is part of the API between nfsd and lockd.
Currently its return value is an on-the-wire NLM status code. But
that forces NFSD to include NLM wire protocol definitions despite
having no other dependency on the NLM wire protocol.
In addition, a CONFIG_LOCKD_V4 Kconfig symbol appears in the middle
of NFSD source code.
Refactor: Let's not use on-the-wire values as part of a high-level
API between two Linux kernel modules. That's what we have errno for,
right?
And, instead of simply moving the CONFIG_LOCKD_V4 check, we can get
rid of it entirely and let the decision of what actual NLM status
code goes on the wire to be left up to NLM version-specific code.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The use of CONFIG_LOCKD_V4 in combination with a later cast_status()
in the NLMv3 code is difficult to reason about. Instead, replace the
use of nlm_deadlock with an implementation-defined status value that
version-specific code translates appropriately.
The new approach establishes a translation boundary: generic lockd
code returns nlm__int__deadlock when posix_lock_file() yields
-EDEADLK. Version-specific handlers (svc4proc.c for NLMv4,
svcproc.c for NLMv3) translate this internal status to the
appropriate wire protocol value. NLMv4 maps to nlm4_deadlock;
NLMv3 maps to nlm_lck_denied (since NLMv3 lacks a deadlock-specific
status code).
Later this modification will also remove the need to include NLMv4
headers in NLMv3 and generic code.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The nlm_drop_reply status code is internal to the kernel's lockd
implementation and must never appear on the wire. Its previous
location in xdr.h grouped it with legitimate NLM protocol status
codes, obscuring this critical distinction.
Relocate the definition to lockd.h with a comment block for internal
status codes, and rename to nlm__int__drop_reply to make its
internal-only nature explicit. This prepares for adding additional
internal status codes in subsequent patches.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clean up: The svcproc.c file handles only NLM v1 and v3 requests.
NLMv4 requests are routed to a separate procedure table in
svc4proc.c, so rqstp->rq_vers can never be 4 in this context.
Remove the unused vers parameter and the dead "vers != 4" check from
cast_to_nlm(). This eliminates the need for the macro wrapper.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Now that there is a runtime debugfs switch, eliminate the compile-time
switch and always build in support for delegated timestamps.
Administrators who previously disabled this feature at compile time can
disable it at runtime via:
echo 0 > /sys/kernel/debug/nfsd/delegated_timestamps
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The delegated timestamp code seems to be working well enough now that we
want to make it always be built in. In the event that there are problems
though, we still want to be able to disable them for debugging purposes.
Add a switch to debugfs to enable them at runtime.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Replace KUnit tests for memcmp() with KUNIT_EXPECT_MEMEQ_MSG() to improve
debugging that prints the hex dump of the buffers when the assertion fails,
whereas memcmp() only returns an integer difference.
Signed-off-by: Ryota Sakamoto <sakamo.ryota@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
When a client holding pNFS SCSI layouts becomes unresponsive, the
server revokes access by preempting the client's SCSI persistent
reservation key. A layout recall is issued for each layout the
client holds; if the client fails to respond, each recall triggers
a fence operation. The first preempt for a given device succeeds
and removes the client's key registration. Subsequent preempts for
the same device fail because the key is no longer registered.
Update the NFS server to handle SCSI persistent registration
fencing on a per-client and per-device basis by utilizing an
xarray associated with the nfs4_client structure.
Each xarray entry is indexed by the dev_t of a block device
registered by the client. The entry maintains a flag indicating
whether this device has already been fenced for the corresponding
client.
When the server issues a persistent registration key to a client,
it creates a new xarray entry at the dev_t index with the fenced
flag initialized to 0.
Before performing a fence via nfsd4_scsi_fence_client, the server
checks the corresponding entry using the device's dev_t. If the
fenced flag is already set, the fence operation is skipped;
otherwise, the flag is set to 1 and fencing proceeds.
The xarray is destroyed when the nfs4_client is released in
__destroy_client.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
1/ consistently use hlist_add_head_rcu() when adding to
the cachelist to reflect the fact that it can be concurrently
walked using RCU. In fact hlist_add_head() has all the needed
barriers so this is no safety issue, primarily a clarity issue.
2/ call cache_get() *before* adding the list with hlist_add_head_rcu().
It is generally safest to inc the refcount before publishing a
reference. In this case it doesn't have any behavioural effect
as code which does an RCU walk does not depend on precision of
the refcount, and it will always be at least one. But it looks
more correct to use this order.
3/ avoid possible races between NULL tests and hlist_entry_safe()
calls. It is possible that a test will find that .next or .head
is not NULL, but hlist_entry_safe() will find that it is NULL.
This can lead to incorrect behaviour with the list-walk terminating
early.
It is safest to always call hlist_entry_safe() and test the result.
Also simplify the *ppos calculation by simply assigning the hash
shifted 32, rather than masking out low bits and incrementing high
bits.
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The svc_rqst->rq_cachetype field is only accessed by nfsd. Move it
into the nfsd_thread_local_info instead.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
rq_lease_breaker has always been a NFSv4 specific layering violation in
svc_rqst. The reason it's there though is that we need a place that is
thread-local, and accessible from the svc_rqst pointer.
Add a new rq_private pointer to struct svc_rqst. This is intended for
use by the threads that are handling the service. sunrpc code doesn't
touch it.
In nfsd, define a new struct nfsd_thread_local_info. nfsd declares one
of these on the stack and puts a pointer to it in rq_private.
Add a new ntli_lease_breaker field to the new struct and convert all of
the places that access rq_lease_breaker to use the new field instead.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Pull vfs fixes from Christian Brauner:
- Fix netfs_limit_iter() hitting BUG() when an ITER_KVEC iterator
reaches it via core dump writes to 9P filesystems. Add ITER_KVEC
handling following the same pattern as the existing ITER_BVEC code.
- Fix a NULL pointer dereference in the netfs unbuffered write retry
path when the filesystem (e.g., 9P) doesn't set the prepare_write
operation.
- Clear I_DIRTY_TIME in sync_lazytime for filesystems implementing
->sync_lazytime. Without this the flag stays set and may cause
additional unnecessary calls during inode deactivation.
- Increase tmpfs size in mount_setattr selftests. A recent commit
bumped the ext4 image size to 2 GB but didn't adjust the tmpfs
backing store, so mkfs.ext4 fails with ENOSPC writing metadata.
- Fix an invalid folio access in iomap when i_blkbits matches the folio
size but differs from the I/O granularity. The cur_folio pointer
would not get invalidated and iomap_read_end() would still be called
on it despite the IO helper owning it.
- Fix hash_name() docstring.
- Fix read abandonment during netfs retry where the subreq variable
used for abandonment could be uninitialized on the first pass or
point to a deleted subrequest on later passes.
- Don't block sync for filesystems with no data integrity guarantees.
Add a SB_I_NO_DATA_INTEGRITY superblock flag replacing the per-inode
AS_NO_DATA_INTEGRITY mapping flag so sync kicks off writeback but
doesn't wait for flusher threads. This fixes a suspend-to-RAM hang on
fuse-overlayfs where the flusher thread blocks when the fuse daemon
is frozen.
- Fix a lockdep splat in iomap when reads fail. iomap_read_end_io()
invokes fserror_report() which calls igrab() taking i_lock in hardirq
context while i_lock is normally held with interrupts enabled. Kick
failed read handling to a workqueue.
- Remove the redundant netfs_io_stream::front member and use
stream->subrequests.next instead, fixing a potential issue in the
direct write code path.
* tag 'vfs-7.0-rc6.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
netfs: Fix the handling of stream->front by removing it
iomap: fix lockdep complaint when reads fail
writeback: don't block sync for filesystems with no data integrity guarantees
netfs: Fix read abandonment during retry
vfs: fix docstring of hash_name()
iomap: fix invalid folio access when i_blkbits differs from I/O granularity
selftests/mount_setattr: increase tmpfs size for idmapped mount tests
fs: clear I_DIRTY_TIME in sync_lazytime
netfs: Fix NULL pointer dereference in netfs_unbuffered_write() on retry
netfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators
Pull phy fixes from Vinod Koul:
- Qualcomm PCS table fix for ufs phy
- TI device node reference fix
- Common prop kconfig fix
- lynx CDR lock workaround for lanes disabled
- usb disconnect function fix of k1 driver
* tag 'phy-fixes-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy:
phy: qcom: qmp-ufs: Fix SM8650 PCS table for Gear 4
phy: ti: j721e-wiz: Fix device node reference leak in wiz_get_lane_phy_types()
phy: k1-usb: add disconnect function support
phy: lynx-28g: skip CDR lock workaround for lanes disabled in the device tree
phy: make PHY_COMMON_PROPS Kconfig symbol conditionally user-selectable
Pull dmaengine fixes from Vinod Koul:
"A bunch of driver fixes with idxd ones being the biggest:
- Xilinx regmap init error handling, dma_device directions, residue
calculation, and reset related timeout fixes
- Renesas CHCTRL updates and driver list fixes
- DW HDMA cycle bits and MSI data programming fix
- IDXD pile of fixes for memeory leak and FLR fixes"
* tag 'dmaengine-fix-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (21 commits)
dmaengine: xilinx_dma: Fix reset related timeout with two-channel AXIDMA
dmaengine: xilinx: xilinx_dma: Fix unmasked residue subtraction
dmaengine: xilinx: xilinx_dma: Fix residue calculation for cyclic DMA
dmaengine: xilinx: xilinx_dma: Fix dma_device directions
dmaengine: sh: rz-dmac: Move CHCTRL updates under spinlock
dmaengine: sh: rz-dmac: Protect the driver specific lists
dmaengine: idxd: fix possible wrong descriptor completion in llist_abort_desc()
dmaengine: xilinx: xdma: Fix regmap init error handling
dmaengine: dw-edma: Fix multiple times setting of the CYCLE_STATE and CYCLE_BIT bits for HDMA.
dmaengine: idxd: Fix leaking event log memory
dmaengine: idxd: Fix freeing the allocated ida too late
dmaengine: idxd: Fix memory leak when a wq is reset
dmaengine: idxd: Fix not releasing workqueue on .release()
dmaengine: idxd: Wait for submitted operations on .device_synchronize()
dmaengine: idxd: Flush all pending descriptors
dmaengine: idxd: Flush kernel workqueues on Function Level Reset
dmaengine: idxd: Fix possible invalid memory access after FLR
dmaengine: idxd: Fix crash when the event log is disabled
dmaengine: idxd: Fix lockdep warnings when calling idxd_device_config()
dmaengine: dw-edma: fix MSI data programming for multi-IRQ case
...
Pull i2c fixes from Wolfram Sang:
- designware: fix resume-probe race causing NULL-deref in amdisp
- imx: fix timeout on repeated reads and extra clock at end
- MAINTAINERS: drop outdated I2C website
* tag 'i2c-for-7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
MAINTAINERS: drop outdated I2C website
i2c: designware: amdisp: Fix resume-probe race condition issue
i2c: imx: ensure no clock is generated after last read
i2c: imx: fix i2c issue when reading multiple messages
Pull kvm fixes from Paolo Bonzini:
"s390:
- Lots of small and not-so-small fixes for the newly rewritten gmap,
mostly affecting the handling of nested guests.
x86:
- Fix an issue with shadow paging, which causes KVM to install an
MMIO PTE in the shadow page tables without first zapping a non-MMIO
SPTE if KVM didn't see the write that modified the shadowed guest
PTE.
While commit a54aa15c6b ("KVM: x86/mmu: Handle MMIO SPTEs
directly in mmu_set_spte()") was right about it being impossible to
miss such a write if it was coming from the guest, it failed to
account for writes to guest memory that are outside the scope of
KVM: if userspace modifies the guest PTE, and then the guest hits a
relevant page fault, KVM will get confused"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE
KVM: x86/mmu: Drop/zap existing present SPTE even when creating an MMIO SPTE
KVM: s390: Fix KVM_S390_VCPU_FAULT ioctl
KVM: s390: vsie: Fix guest page tables protection
KVM: s390: vsie: Fix unshadowing while shadowing
KVM: s390: vsie: Fix refcount overflow for shadow gmaps
KVM: s390: vsie: Fix nested guest memory shadowing
KVM: s390: Correctly handle guest mappings without struct page
KVM: s390: Fix gmap_link()
KVM: s390: vsie: Fix check for pre-existing shadow mapping
KVM: s390: Remove non-atomic dat_crstep_xchg()
KVM: s390: vsie: Fix dat_split_ste()
Pull xen fix from Juergen Gross:
"A single fix for a very rare bug introduced in rc5"
* tag 'for-linus-7.0a-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/privcmd: unregister xenstore notifier on module exit
Pull x86 fixes from Ingo Molnar:
- Fix an early boot crash in AMD SEV-SNP guests, caused by incorrect
FSGSBASE init ordering (Nikunj A Dadhania)
- Remove X86_CR4_FRED from the CR4 pinned bits mask, to fix a race
window during the bootup of SEV-{ES,SNP} or TDX guests, which can
crash them if they trigger exceptions in that window (Borislav
Petkov)
- Fix early boot failures on SEV-ES/SNP guests, due to incorrect early
GHCB access (Nikunj A Dadhania)
- Add clarifying comment to the CRn pinning logic, to avoid future
confusion & bugs (Peter Zijlstra)
* tag 'x86-urgent-2026-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Add comment clarifying CRn pinning
x86/fred: Fix early boot failures on SEV-ES/SNP guests
x86/cpu: Remove X86_CR4_FRED from the CR4 pinned bits mask
x86/cpu: Enable FSGSBASE early in cpu_init_exception_handling()
Pull timer fix from Ingo Molnar:
"Fix an argument order bug in the alarm timer forwarding logic, which
may cause missed expirations or incorrect overrun accounting"
* tag 'timers-urgent-2026-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
alarmtimer: Fix argument order in alarm_timer_forward()
Pull futex fixes from Ingo Molnar:
- Tighten up the sys_futex_requeue() ABI a bit, to disallow dissimilar
futex flags and potential UaF access (Peter Zijlstra)
- Fix UaF between futex_key_to_node_opt() and vma_replace_policy()
(Hao-Yu Yang)
- Clear stale exiting pointer in futex_lock_pi() retry path, which
triggered a warning (and potential misbehavior) in stress-testing
(Davidlohr Bueso)
* tag 'locking-urgent-2026-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Clear stale exiting pointer in futex_lock_pi() retry path
futex: Fix UaF between futex_key_to_node_opt() and vma_replace_policy()
futex: Require sys_futex_requeue() to have identical flags
Pull overlayfs fixes from Amir Goldstein:
- Fix regression in 'xino' feature detection
I clumsily introduced this regression myself when working on another
subsystem (fsnotify). Both the regression and the fix have almost no
visible impact on users except for some kmsg prints.
- Fix to performance regression in v6.12.
This regression was reported by Google COS developers.
It is not uncommon these days for the year-old mature LTS to get
adopted by distros and get exposed to many new workloads. We made a
sub-smart move of making a behavior change in v6.12 which could
impact performance, without making it opt-in. Fixing this mistake
retroactively, to be picked by LTS.
* tag 'ovl-fixes-7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs:
ovl: make fsync after metadata copy-up opt-in mount option
ovl: fix wrong detection of 32bit inode numbers
Pull ext4 fixes from Ted Ts'o:
- Update the MAINTAINERS file to add reviewers for the ext4 file system
- Add a test issue an ext4 warning (not a WARN_ON) if there are still
dirty pages attached to an evicted inode.
- Fix a number of Syzkaller issues
- Fix memory leaks on error paths
- Replace some BUG and WARN with EFSCORRUPTED reporting
- Fix a potential crash when disabling discard via remount followed by
an immediate unmount. (Found by Sashiko)
- Fix a corner case which could lead to allocating blocks for an
indirect-mapped inode block numbers > 2**32
- Fix a race when reallocating a freed inode that could result in a
deadlock
- Fix a user-after-free in update_super_work when racing with umount
- Fix build issues when trying to build ext4's kunit tests as a module
- Fix a bug where ext4_split_extent_zeroout() could fail to pass back
an error from ext4_ext_dirty()
- Avoid allocating blocks from a corrupted block group in
ext4_mb_find_by_goal()
- Fix a percpu_counters list corruption BUG triggered by an ext4
extents kunit
- Fix a potetial crash caused by the fast commit flush path potentially
accessing the jinode structure before it is fully initialized
- Fix fsync(2) in no-journal mode to make sure the dirtied inode is
write to storage
- Fix a bug when in no-journal mode, when ext4 tries to avoid using
recently deleted inodes, if lazy itable initialization is enabled,
can lead to an unitialized inode getting skipped and triggering an
e2fsck complaint
- Fix journal credit calculation when setting an xattr when both the
encryption and ea_inode feeatures are enabled
- Fix corner cases which could result in stale xarray tags after
writeback
- Fix generic/475 failures caused by ENOSPC errors while creating a
symlink when the system crashes resulting to a file system
inconsistency when replaying the fast commit journal
* tag 'ext4_for_linus-7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (27 commits)
ext4: always drain queued discard work in ext4_mb_release()
ext4: handle wraparound when searching for blocks for indirect mapped blocks
ext4: skip split extent recovery on corruption
ext4: fix iloc.bh leak in ext4_fc_replay_inode() error paths
ext4: fix deadlock on inode reallocation
ext4: fix use-after-free in update_super_work when racing with umount
ext4: fix the might_sleep() warnings in kvfree()
ext4: reject mount if bigalloc with s_first_data_block != 0
ext4: fix extents-test.c is not compiled when EXT4_KUNIT_TESTS=M
ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M
ext4: introduce EXPORT_SYMBOL_FOR_EXT4_TEST() helper
jbd2: gracefully abort on checkpointing state corruptions
ext4: avoid infinite loops caused by residual data
ext4: validate p_idx bounds in ext4_ext_correct_indexes
ext4: test if inode's all dirty pages are submitted to disk
ext4: minor fix for ext4_split_extent_zeroout()
ext4: avoid allocate block from corrupted group in ext4_mb_find_by_goal()
ext4: kunit: extents-test: lix percpu_counters list corruption
ext4: publish jinode after initialization
ext4: replace BUG_ON with proper error handling in ext4_read_inline_folio
...
Pull btrfs fixes from David Sterba:
"A few more fixes. There's one that stands out in size as it fixes an
edge case in fsync.
- fix issue on fsync where file with zero size appears as a non-zero
after log replay
- in zlib compression, handle a crash when data alignment causes
folio reference issues
- fix possible crash with enabled tracepoints on a overlayfs mount
- handle device stats update error
- on zoned filesystems, fix kobject leak on sub-block groups
- fix super block offset in an error message in validation"
* tag 'for-7.0-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix lost error when running device stats on multiple devices fs
btrfs: tracepoints: get correct superblock from dentry in event btrfs_sync_file()
btrfs: zlib: handle page aligned compressed size correctly
btrfs: fix leak of kobject name for sub-group space_info
btrfs: fix zero size inode with non-zero size after log replay
btrfs: fix super block offset in error message in btrfs_validate_super()
Pull misc fixes from Andrew Morton:
"10 hotfixes. 8 are cc:stable. 9 are for MM.
There's a 3-patch series of DAMON fixes from Josh Law and SeongJae
Park. The rest are singletons - please see the changelogs for details"
* tag 'mm-hotfixes-stable-2026-03-28-10-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/mseal: update VMA end correctly on merge
bug: avoid format attribute warning for clang as well
mm/pagewalk: fix race between concurrent split and refault
mm/memory: fix PMD/PUD checks in follow_pfnmap_start()
mm/damon/sysfs: check contexts->nr in repeat_call_fn
mm/damon/sysfs: check contexts->nr before accessing contexts_arr[0]
mm/damon/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx() failure
mm/swap: fix swap cache memcg accounting
MAINTAINERS, mailmap: update email address for Harry Yoo
mm/huge_memory: fix folio isn't locked in softleaf_to_folio()
As stated on the website: "This wiki has been archived and the content
is no longer updated." No need to reference it.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Pull tracing fixes from Steven Rostedt:
- Fix potential deadlock in osnoise and hotplug
The interface_lock can be called by a osnoise thread and the CPU
shutdown logic of osnoise can wait for this thread to finish. But
cpus_read_lock() can also be taken while holding the interface_lock.
This produces a circular lock dependency and can cause a deadlock.
Swap the ordering of cpus_read_lock() and the interface_lock to have
interface_lock taken within the cpus_read_lock() context to prevent
this circular dependency.
- Fix freeing of event triggers in early boot up
If the same trigger is added on the kernel command line, the second
one will fail to be applied and the trigger created will be freed.
This calls into the deferred logic and creates a kernel thread to do
the freeing. But the command line logic is called before kernel
threads can be created and this leads to a NULL pointer dereference.
Delay freeing event triggers until late init.
* tag 'trace-v7.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Drain deferred trigger frees if kthread creation fails
tracing: Fix potential deadlock in cpu hotplug with osnoise
Pull s390 fixes from Vasily Gorbik:
- Add array_index_nospec() to syscall dispatch table lookup to prevent
limited speculative out-of-bounds access with user-controlled syscall
number
- Mark array_index_mask_nospec() __always_inline since GCC may emit an
out-of-line call instead of the inline data dependency sequence the
mitigation relies on
- Clear r12 on kernel entry to prevent potential speculative use of
user value in system_call, ext/io/mcck interrupt handlers
* tag 's390-7.0-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/entry: Scrub r12 register on kernel entry
s390/syscalls: Add spectre boundary for syscall dispatch table
s390/barrier: Make array_index_mask_nospec() __always_inline
Fuzzying/stressing futexes triggered:
WARNING: kernel/futex/core.c:825 at wait_for_owner_exiting+0x7a/0x80, CPU#11: futex_lock_pi_s/524
When futex_lock_pi_atomic() sees the owner is exiting, it returns -EBUSY
and stores a refcounted task pointer in 'exiting'.
After wait_for_owner_exiting() consumes that reference, the local pointer
is never reset to nil. Upon a retry, if futex_lock_pi_atomic() returns a
different error, the bogus pointer is passed to wait_for_owner_exiting().
CPU0 CPU1 CPU2
futex_lock_pi(uaddr)
// acquires the PI futex
exit()
futex_cleanup_begin()
futex_state = EXITING;
futex_lock_pi(uaddr)
futex_lock_pi_atomic()
attach_to_pi_owner()
// observes EXITING
*exiting = owner; // takes ref
return -EBUSY
wait_for_owner_exiting(-EBUSY, owner)
put_task_struct(); // drops ref
// exiting still points to owner
goto retry;
futex_lock_pi_atomic()
lock_pi_update_atomic()
cmpxchg(uaddr)
*uaddr ^= WAITERS // whatever
// value changed
return -EAGAIN;
wait_for_owner_exiting(-EAGAIN, exiting) // stale
WARN_ON_ONCE(exiting)
Fix this by resetting upon retry, essentially aligning it with requeue_pi.
Fixes: 3ef240eaff ("futex: Prevent exit livelock")
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260326001759.4129680-1-dave@stgolabs.net
Boot-time trigger registration can fail before the trigger-data cleanup
kthread exists. Deferring those frees until late init is fine, but the
post-boot fallback must still drain the deferred list if kthread
creation never succeeds.
Otherwise, boot-deferred nodes can accumulate on
trigger_data_free_list, later frees fall back to synchronously freeing
only the current object, and the older queued entries are leaked
forever.
To trigger this, add the following to the kernel command line:
trace_event=sched_switch trace_trigger=sched_switch.traceon,sched_switch.traceon
The second traceon trigger will fail and be freed. This triggers a NULL
pointer dereference and crashes the kernel.
Keep the deferred boot-time behavior, but when kthread creation fails,
drain the whole queued list synchronously. Do the same in the late-init
drain path so queued entries are not stranded there either.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260324221326.1395799-3-atwellwea@gmail.com
Fixes: 61d445af0a ("tracing: Add bulk garbage collection of freeing event_trigger_data")
Signed-off-by: Wesley Atwell <atwellwea@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
follow_pfnmap_start() suffers from two problems:
(1) We are not re-fetching the pmd/pud after taking the PTL
Therefore, we are not properly stabilizing what the lock actually
protects. If there is concurrent zapping, we would indicate to the
caller that we found an entry, however, that entry might already have
been invalidated, or contain a different PFN after taking the lock.
Properly use pmdp_get() / pudp_get() after taking the lock.
(2) pmd_leaf() / pud_leaf() are not well defined on non-present entries
pmd_leaf()/pud_leaf() could wrongly trigger on non-present entries.
There is no real guarantee that pmd_leaf()/pud_leaf() returns something
reasonable on non-present entries. Most architectures indeed either
perform a present check or make it work by smart use of flags.
However, for example loongarch checks the _PAGE_HUGE flag in pmd_leaf(),
and always sets the _PAGE_HUGE flag in __swp_entry_to_pmd(). Whereby
pmd_trans_huge() explicitly checks pmd_present(), pmd_leaf() does not do
that.
Let's check pmd_present()/pud_present() before assuming "the is a present
PMD leaf" when spotting pmd_leaf()/pud_leaf(), like other page table
handling code that traverses user page tables does.
Given that non-present PMD entries are likely rare in VM_IO|VM_PFNMAP, (1)
is likely more relevant than (2). It is questionable how often (1) would
actually trigger, but let's CC stable to be sure.
This was found by code inspection.
Link: https://lkml.kernel.org/r/20260323-follow_pfnmap_fix-v1-1-5b0ec10872b3@kernel.org
Fixes: 6da8e9634b ("mm: new follow_pfnmap API")
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Multiple sysfs command paths dereference contexts_arr[0] without first
verifying that kdamond->contexts->nr == 1. A user can set nr_contexts to
0 via sysfs while DAMON is running, causing NULL pointer dereferences.
In more detail, the issue can be triggered by privileged users like
below.
First, start DAMON and make contexts directory empty
(kdamond->contexts->nr == 0).
# damo start
# cd /sys/kernel/mm/damon/admin/kdamonds/0
# echo 0 > contexts/nr_contexts
Then, each of below commands will cause the NULL pointer dereference.
# echo update_schemes_stats > state
# echo update_schemes_tried_regions > state
# echo update_schemes_tried_bytes > state
# echo update_schemes_effective_quotas > state
# echo update_tuned_intervals > state
Guard all commands (except OFF) at the entry point of
damon_sysfs_handle_cmd().
Link: https://lkml.kernel.org/r/20260321175427.86000-3-sj@kernel.org
Fixes: 0ac32b8aff ("mm/damon/sysfs: support DAMOS stats")
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [5.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
