kernel/linux.git/include/linux/filelock.h, branch v6.12.80

vfs: dodge smp_mb in break_lease and break_deleg in the common case

2024-08-30T06:22:33+00:00

These inlines show up in the fast path (e.g., in do_dentry_open()) and induce said full barrier regarding i_flctx access when in most cases the pointer is NULL. The pointer can be safely checked before issuing the barrier, dodging it in most cases as a result. It is plausible the consume fence would be sufficient, but I don't want to go audit all callers regarding what they before calling here. Signed-off-by: Mateusz Guzik Link: https://lore.kernel.org/r/20240806172846.886570-1-mjguzik@gmail.com Reviewed-by: Jeff Layton Signed-off-by: Christian Brauner

filelock: always define for_each_file_lock()

2024-02-12T13:08:18+00:00

...and eliminate the stub version when CONFIG_FILE_LOCKING is disabled. This silences the following warning that crept in recently: fs/ceph/locks.c: In function 'ceph_count_locks': fs/ceph/locks.c:380:27: error: unused variable 'lock' [-Werror=unused-variable] 380 | struct file_lock *lock; Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202402062210.3YyBVGF1-lkp@intel.com/ Fixes: 75cabec0111b ("filelock: add some new helper functions") Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20240212-flsplit3-v1-1-019f0ad6bf69@kernel.org Signed-off-by: Christian Brauner

filelock: don't do security checks on nfsd setlease calls

2024-02-05T12:53:03+00:00

Zdenek reported seeing some AVC denials due to nfsd trying to set delegations: type=AVC msg=audit(09.11.2023 09:03:46.411:496) : avc: denied { lease } for pid=5127 comm=rpc.nfsd capability=lease scontext=system_u:system_r:nfsd_t:s0 tcontext=system_u:system_r:nfsd_t:s0 tclass=capability permissive=0 When setting delegations on behalf of nfsd, we don't want to do all of the normal capabilty and LSM checks. nfsd is a kernel thread and runs with CAP_LEASE set, so the uid checks end up being a no-op in most cases anyway. Some nfsd functions can end up running in normal process context when tearing down the server. At that point, the CAP_LEASE check can fail and cause the client to not tear down delegations when expected. Also, the way the per-fs ->setlease handlers work today is a little convoluted. The non-trivial ones are wrappers around generic_setlease, so when they fail due to permission problems they usually they end up doing a little extra work only to determine that they can't set the lease anyway. It would be more efficient to do those checks earlier. Transplant the permission checking from generic_setlease to vfs_setlease, which will make the permission checking happen earlier on filesystems that have a ->setlease operation. Add a new kernel_setlease function that bypasses these checks, and switch nfsd to use that instead of vfs_setlease. There is one behavioral change here: prior this patch the setlease_notifier would fire even if the lease attempt was going to fail the security checks later. With this change, it doesn't fire until the caller has passed them. I think this is a desirable change overall. nfsd is the only user of the setlease_notifier and it doesn't benefit from being notified about failed attempts. Cc: Ondrej Mosnáček Reported-by: Zdenek Pytela Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2248830 Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20240205-bz2248830-v1-1-d0ec0daecba1@kernel.org Acked-by: Tom Talpey Reviewed-by: NeilBrown Signed-off-by: Christian Brauner

filelock: split leases out of struct file_lock

2024-02-05T12:11:44+00:00

Add a new struct file_lease and move the lease-specific fields from struct file_lock to it. Convert the appropriate API calls to take struct file_lease instead, and convert the callers to use them. There is zero overlap between the lock manager operations for file locks and the ones for file leases, so split the lease-related operations off into a new lease_manager_operations struct. Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20240131-flsplit-v3-47-c6129007ee8d@kernel.org Reviewed-by: NeilBrown Signed-off-by: Christian Brauner

filelock: remove temporary compatibility macros

2024-02-05T12:11:44+00:00

Everything has been converted to access fl_core fields directly, so we can now drop these. Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20240131-flsplit-v3-46-c6129007ee8d@kernel.org Reviewed-by: NeilBrown Signed-off-by: Christian Brauner

filelock: convert fl_blocker to file_lock_core

2024-02-05T12:11:40+00:00

Both locks and leases deal with fl_blocker. Switch the fl_blocker pointer in struct file_lock_core to point to the file_lock_core of the blocker instead of a file_lock structure. Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20240131-flsplit-v3-26-c6129007ee8d@kernel.org Reviewed-by: NeilBrown Signed-off-by: Christian Brauner

filelock: split common fields into struct file_lock_core

2024-02-05T12:11:38+00:00

In a future patch, we're going to split file leases into their own structure. Since a lot of the underlying machinery uses the same fields move those into a new file_lock_core, and embed that inside struct file_lock. For now, add some macros to ensure that we can continue to build while the conversion is in progress. Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20240131-flsplit-v3-17-c6129007ee8d@kernel.org Reviewed-by: NeilBrown Signed-off-by: Christian Brauner

filelock: add some new helper functions

2024-02-05T12:11:35+00:00

In later patches we're going to embed some common fields into a new structure inside struct file_lock. Smooth the transition by adding some new helper functions, and converting the core file locking code to use them. Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20240131-flsplit-v3-4-c6129007ee8d@kernel.org Reviewed-by: NeilBrown Signed-off-by: Christian Brauner

filelock: fl_pid field should be signed int

2024-02-02T11:09:04+00:00

This field has been unsigned for a very long time, but most users of the struct file_lock and the file locking internals themselves treat it as a signed value. Change it to be pid_t (which is a signed int). Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20240131-flsplit-v3-1-c6129007ee8d@kernel.org Reviewed-by: NeilBrown Signed-off-by: Christian Brauner

fs: Pass argument to fcntl_setlease as int

2023-07-10T12:36:11+00:00

The interface for fcntl expects the argument passed for the command F_SETLEASE to be of type int. The current code wrongly treats it as a long. In order to avoid access to undefined bits, we should explicitly cast the argument to int. Cc: Alexander Viro Cc: Christian Brauner Cc: Jeff Layton Cc: Chuck Lever Cc: Trond Myklebust Cc: Anna Schumaker Cc: Kevin Brodsky Cc: Vincenzo Frascino Cc: Szabolcs Nagy Cc: "Theodore Ts'o" Cc: David Laight Cc: Mark Rutland Cc: linux-fsdevel@vger.kernel.org Cc: linux-cifs@vger.kernel.org Cc: linux-nfs@vger.kernel.org Cc: linux-morello@op-lists.linaro.org Signed-off-by: Luca Vizzarro Message-Id: <20230414152459.816046-3-Luca.Vizzarro@arm.com> Signed-off-by: Christian Brauner