commit 22e111ed6c83dcde3037fc81176012721bc34c0b upstream. We should never lock two subdirectories without having taken ->s_vfs_rename_mutex; inode pointer order or not, the "order" proposed in 28eceeda130f "fs: Lock moved directories" is not transitive, with the usual consequences. The rationale for locking renamed subdirectory in all cases was the possibility of race between rename modifying .. in a subdirectory to reflect the new parent and another thread modifying the same subdirectory. For a lot of filesystems that's not a problem, but for some it can lead to trouble (e.g. the case when short directory contents is kept in the inode, but creating a file in it might push it across the size limit and copy its contents into separate data block(s)). However, we need that only in case when the parent does change - otherwise ->rename() doesn't need to do anything with .. entry in the first place. Some instances are lazy and do a tautological update anyway, but it's really not hard to avoid. Amended locking rules for rename(): find the parent(s) of source and target if source and target have the same parent lock the common parent else lock ->s_vfs_rename_mutex lock both parents, in ancestor-first order; if neither is an ancestor of another, lock the parent of source first. find the source and target. if source and target have the same parent if operation is an overwriting rename of a subdirectory lock the target subdirectory else if source is a subdirectory lock the source if target is a subdirectory lock the target lock non-directories involved, in inode pointer order if both source and target are such. That way we are guaranteed that parents are locked (for obvious reasons), that any renamed non-directory is locked (nfsd relies upon that), that any victim is locked (emptiness check needs that, among other things) and subdirectory that changes parent is locked (needed to protect the update of .. entries). We are also guaranteed that any operation locking more than one directory either takes ->s_vfs_rename_mutex or locks a parent followed by its child. Cc: stable@vger.kernel.org Fixes: 28eceeda130f "fs: Lock moved directories" Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 28eceeda130f5058074dd007d9c59d2e8bc5af2e upstream. When a directory is moved to a different directory, some filesystems (udf, ext4, ocfs2, f2fs, and likely gfs2, reiserfs, and others) need to update their pointer to the parent and this must not race with other operations on the directory. Lock the directories when they are moved. Although not all filesystems need this locking, we perform it in vfs_rename() because getting the lock ordering right is really difficult and we don't want to expose these locking details to filesystems. CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Message-Id: <20230601105830.13168-5-jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e910c8e3aa02dc456e2f4c32cb479523c326b534 upstream.
Commit df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") introduced a warning
for the autofs_dev_ioctl structure:
In function 'check_name',
inlined from 'validate_dev_ioctl' at fs/autofs/dev-ioctl.c:131:9,
inlined from '_autofs_dev_ioctl' at fs/autofs/dev-ioctl.c:624:8:
fs/autofs/dev-ioctl.c:33:14: error: 'strchr' reading 1 or more bytes from a region of size 0 [-Werror=stringop-overread]
33 | if (!strchr(name, '/'))
| ^~~~~~~~~~~~~~~~~
In file included from include/linux/auto_dev-ioctl.h:10,
from fs/autofs/autofs_i.h:10,
from fs/autofs/dev-ioctl.c:14:
include/uapi/linux/auto_dev-ioctl.h: In function '_autofs_dev_ioctl':
include/uapi/linux/auto_dev-ioctl.h:112:14: note: source object 'path' of size 0
112 | char path[0];
| ^~~~
This is easily fixed by changing the gnu 0-length array into a c99
flexible array. Since this is a uapi structure, we have to be careful
about possible regressions but this one should be fine as they are
equivalent here. While it would break building with ancient gcc versions
that predate c99, it helps building with --std=c99 and -Wpedantic builds
in user space, as well as non-gnu compilers. This means we probably
also want it fixed in stable kernels.
Cc: stable@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230523081944.581710-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 74596085796fae0cfce3e42ee46bf4f8acbdac55 ]
The details for struct dentry_operations member d_weak_revalidate is
missing a "d_" prefix.
Fixes: af96c1e304f7 ("docs: filesystems: vfs: Convert vfs.txt to RST")
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20230227184042.2375235-1-development@efficientek.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e3ea75ee651daf5e434afbfdb7dbf75e200ea1f6 upstream.
Before the commit 461c3af045d3 ("ext4: Change handle_mount_opt() to use
fs_parameter") ext4 mount option journal_path did follow links in the
provided path.
Bring this behavior back by allowing to pass pathwalk flags to
fs_lookup_param().
Fixes: 461c3af045d3 ("ext4: Change handle_mount_opt() to use fs_parameter")
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20221004135803.32283-1-lczerner@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull documentation fixes from Jonathan Corbet: "A handful of relatively simple documentation fixes, plus a set of patches catching the Chinese translation up with the front-page rework" * tag 'docs-6.1-2' of git://git.lwn.net/linux: Documentation: rtla: Correct command line example docs/zh_CN: add a man-pages link to zh_CN/index.rst docs/zh_CN: Rewrite the Chinese translation front page docs/zh_CN: add zh_CN/arch.rst docs/zh_CN: promote the title of zh_CN/process/index.rst docs/zh_CN: Update the translation of page_owner to 6.0-rc7 docs/zh_CN: Update the translation of ksm to 6.0-rc7 docs/howto: Replace abundoned URL of gmane.org Documentation: ubifs: Fix compression idiom Documentation/mm/page_owner.rst: delete frequently changing experimental data docs/zh_CN: Fix build warning docs: ftrace: Correct access mode
Pull ceph updates from Ilya Dryomov: "A quiet round this time: several assorted filesystem fixes, the most noteworthy one being some additional wakeups in cap handling code, and a messenger cleanup" * tag 'ceph-for-6.1-rc1' of https://github.com/ceph/ceph-client: ceph: remove Sage's git tree from documentation ceph: fix incorrectly showing the .snap size for stat ceph: fail the open_by_handle_at() if the dentry is being unlinked ceph: increment i_version when doing a setattr with caps ceph: Use kcalloc for allocating multiple elements ceph: no need to wait for transition RDCACHE|RD -> RD ceph: fail the request if the peer MDS doesn't support getvxattr op ceph: wake up the waiters if any new caps comes libceph: drop last_piece flag from ceph_msg_data_cursor
Pull vfs tmpfile updates from Al Viro: "Miklos' ->tmpfile() signature change; pass an unopened struct file to it, let it open the damn thing. Allows to add tmpfile support to FUSE" * tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fuse: implement ->tmpfile() vfs: open inside ->tmpfile() vfs: move open right after ->tmpfile() vfs: make vfs_tmpfile() static ovl: use vfs_tmpfile_open() helper cachefiles: use vfs_tmpfile_open() helper cachefiles: only pass inode to *mark_inode_inuse() helpers cachefiles: tmpfile error handling cleanup hugetlbfs: cleanup mknod and tmpfile vfs: add vfs_tmpfile_open() helper
Clearly the author meant 'on the fly'. Signed-off-by: Joel Stanley <joel@jms.id.au> Link: https://lore.kernel.org/r/20221005030904.65604-1-joel@jms.id.au Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Pull kvm updates from Paolo Bonzini:
"The first batch of KVM patches, mostly covering x86.
ARM:
- Account stage2 page table allocations in memory stats
x86:
- Account EPT/NPT arm64 page table allocations in memory stats
- Tracepoint cleanups/fixes for nested VM-Enter and emulated MSR
accesses
- Drop eVMCS controls filtering for KVM on Hyper-V, all known
versions of Hyper-V now support eVMCS fields associated with
features that are enumerated to the guest
- Use KVM's sanitized VMCS config as the basis for the values of
nested VMX capabilities MSRs
- A myriad event/exception fixes and cleanups. Most notably, pending
exceptions morph into VM-Exits earlier, as soon as the exception is
queued, instead of waiting until the next vmentry. This fixed a
longstanding issue where the exceptions would incorrecly become
double-faults instead of triggering a vmexit; the common case of
page-fault vmexits had a special workaround, but now it's fixed for
good
- A handful of fixes for memory leaks in error paths
- Cleanups for VMREAD trampoline and VMX's VM-Exit assembly flow
- Never write to memory from non-sleepable kvm_vcpu_check_block()
- Selftests refinements and cleanups
- Misc typo cleanups
Generic:
- remove KVM_REQ_UNHALT"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (94 commits)
KVM: remove KVM_REQ_UNHALT
KVM: mips, x86: do not rely on KVM_REQ_UNHALT
KVM: x86: never write to memory from kvm_vcpu_check_block()
KVM: x86: Don't snapshot pending INIT/SIPI prior to checking nested events
KVM: nVMX: Make event request on VMXOFF iff INIT/SIPI is pending
KVM: nVMX: Make an event request if INIT or SIPI is pending on VM-Enter
KVM: SVM: Make an event request if INIT or SIPI is pending when GIF is set
KVM: x86: lapic does not have to process INIT if it is blocked
KVM: x86: Rename kvm_apic_has_events() to make it INIT/SIPI specific
KVM: x86: Rename and expose helper to detect if INIT/SIPI are allowed
KVM: nVMX: Make an event request when pending an MTF nested VM-Exit
KVM: x86: make vendor code check for all nested events
mailmap: Update Oliver's email address
KVM: x86: Allow force_emulation_prefix to be written without a reload
KVM: selftests: Add an x86-only test to verify nested exception queueing
KVM: selftests: Use uapi header to get VMX and SVM exit reasons/codes
KVM: x86: Rename inject_pending_events() to kvm_check_and_inject_events()
KVM: VMX: Update MTF and ICEBP comments to document KVM's subtle behavior
KVM: x86: Treat pending TRIPLE_FAULT requests as pending exceptions
KVM: x86: Morph pending exceptions to pending VM-Exits at queue time
...