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11 daysNFSv4: include MAY_WRITE in open permission mask for O_TRUNCBenjamin Coddington
POSIX requires write permission to truncate a file, so an open() that specifies O_TRUNC must be authorized for write access regardless of the O_ACCMODE access mode. nfs_open_permission_mask() builds the access mask passed to nfs_may_open(), which is the local authorization gate for OPENs the client serves itself from a cached write delegation via the can_open_delegated() path in nfs4_try_open_cached(). The mask is derived from O_ACCMODE alone, so an open(O_RDONLY | O_TRUNC) against a file the caller cannot write requests only MAY_READ and passes the local check. The OPEN is then satisfied locally and the truncation is issued to the server as a SETATTR(size=0) over the delegation stateid, which the server accepts under standard write-delegation semantics. POSIX requires that this open fail with EACCES. Include MAY_WRITE in the mask whenever O_TRUNC is set so the local check matches the access the server would have enforced. Suggested-by: Trond Myklebust <trondmy@kernel.org> Fixes: af22f94ae02a ("NFSv4: Simplify _nfs4_do_access()") Cc: stable@vger.kernel.org Signed-off-by: Benjamin Coddington <bcodding@hammerspace.com> Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>
2026-06-23Merge tag 'nfs-for-7.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds
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 ...
2026-06-15Merge tag 'pull-dcache' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 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 ...
2026-06-09NFS: correct CONFIG_NFS_V4 macro name in #endif commentEthan Nelson-Moore
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>
2026-06-08nfs: remove nfs_compat_user_ino64() and deprecate enable_ino64Jeff Layton
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>
2026-06-08nfs: store the full NFS fileid in inode->i_inoJeff Layton
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>
2026-06-05VFS: use wait_var_event for waiting in d_alloc_parallel()NeilBrown
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>
2026-05-21openat2: new OPENAT2_REGULAR flag supportDorjoy Chowdhury
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>
2026-04-21Merge tag 'pull-dcache-busy-wait' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 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
2026-04-15Merge tag 'mm-stable-2026-04-13-21-45' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "maple_tree: Replace big node with maple copy" (Liam Howlett) Mainly prepararatory work for ongoing development but it does reduce stack usage and is an improvement. - "mm, swap: swap table phase III: remove swap_map" (Kairui Song) Offers memory savings by removing the static swap_map. It also yields some CPU savings and implements several cleanups. - "mm: memfd_luo: preserve file seals" (Pratyush Yadav) File seal preservation to LUO's memfd code - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan Chen) Additional userspace stats reportng to zswap - "arch, mm: consolidate empty_zero_page" (Mike Rapoport) Some cleanups for our handling of ZERO_PAGE() and zero_pfn - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu Han) A robustness improvement and some cleanups in the kmemleak code - "Improve khugepaged scan logic" (Vernon Yang) Improve khugepaged scan logic and reduce CPU consumption by prioritizing scanning tasks that access memory frequently - "Make KHO Stateless" (Jason Miu) Simplify Kexec Handover by transitioning KHO from an xarray-based metadata tracking system with serialization to a radix tree data structure that can be passed directly to the next kernel - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas Ballasi and Steven Rostedt) Enhance vmscan's tracepointing - "mm: arch/shstk: Common shadow stack mapping helper and VM_NOHUGEPAGE" (Catalin Marinas) Cleanup for the shadow stack code: remove per-arch code in favour of a generic implementation - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin) Fix a WARN() which can be emitted the KHO restores a vmalloc area - "mm: Remove stray references to pagevec" (Tal Zussman) Several cleanups, mainly udpating references to "struct pagevec", which became folio_batch three years ago - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl Shutsemau) Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail pages encode their relationship to the head page - "mm/damon/core: improve DAMOS quota efficiency for core layer filters" (SeongJae Park) Improve two problematic behaviors of DAMOS that makes it less efficient when core layer filters are used - "mm/damon: strictly respect min_nr_regions" (SeongJae Park) Improve DAMON usability by extending the treatment of the min_nr_regions user-settable parameter - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka) The proper fix for a previously hotfixed SMP=n issue. Code simplifications and cleanups ensued - "mm: cleanups around unmapping / zapping" (David Hildenbrand) A bunch of cleanups around unmapping and zapping. Mostly simplifications, code movements, documentation and renaming of zapping functions - "support batched checking of the young flag for MGLRU" (Baolin Wang) Batched checking of the young flag for MGLRU. It's part cleanups; one benchmark shows large performance benefits for arm64 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner) memcg cleanup and robustness improvements - "Allow order zero pages in page reporting" (Yuvraj Sakshith) Enhance free page reporting - it is presently and undesirably order-0 pages when reporting free memory. - "mm: vma flag tweaks" (Lorenzo Stoakes) Cleanup work following from the recent conversion of the VMA flags to a bitmap - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae Park) Add some more developer-facing debug checks into DAMON core - "mm/damon: test and document power-of-2 min_region_sz requirement" (SeongJae Park) An additional DAMON kunit test and makes some adjustments to the addr_unit parameter handling - "mm/damon/core: make passed_sample_intervals comparisons overflow-safe" (SeongJae Park) Fix a hard-to-hit time overflow issue in DAMON core - "mm/damon: improve/fixup/update ratio calculation, test and documentation" (SeongJae Park) A batch of misc/minor improvements and fixups for DAMON - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David Hildenbrand) Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code movement was required. - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky) A somewhat random mix of fixups, recompression cleanups and improvements in the zram code - "mm/damon: support multiple goal-based quota tuning algorithms" (SeongJae Park) Extend DAMOS quotas goal auto-tuning to support multiple tuning algorithms that users can select - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao) Fix the khugpaged sysfs handling so we no longer spam the logs with reams of junk when starting/stopping khugepaged - "mm: improve map count checks" (Lorenzo Stoakes) Provide some cleanups and slight fixes in the mremap, mmap and vma code - "mm/damon: support addr_unit on default monitoring targets for modules" (SeongJae Park) Extend the use of DAMON core's addr_unit tunable - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache) Cleanups to khugepaged and is a base for Nico's planned khugepaged mTHP support - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand) Code movement and cleanups in the memhotplug and sparsemem code - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup CONFIG_MIGRATION" (David Hildenbrand) Rationalize some memhotplug Kconfig support - "change young flag check functions to return bool" (Baolin Wang) Cleanups to change all young flag check functions to return bool - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh Law and SeongJae Park) Fix a few potential DAMON bugs - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo Stoakes) Convert a lot of the existing use of the legacy vm_flags_t data type to the new vma_flags_t type which replaces it. Mainly in the vma code. - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes) Expand the mmap_prepare functionality, which is intended to replace the deprecated f_op->mmap hook which has been the source of bugs and security issues for some time. Cleanups, documentation, extension of mmap_prepare into filesystem drivers - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes) Simplify and clean up zap_huge_pmd(). Additional cleanups around vm_normal_folio_pmd() and the softleaf functionality are performed. * tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm: fix deferred split queue races during migration mm/khugepaged: fix issue with tracking lock mm/huge_memory: add and use has_deposited_pgtable() mm/huge_memory: add and use normal_or_softleaf_folio_pmd() mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio() mm/huge_memory: separate out the folio part of zap_huge_pmd() mm/huge_memory: use mm instead of tlb->mm mm/huge_memory: remove unnecessary sanity checks mm/huge_memory: deduplicate zap deposited table call mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE() mm/huge_memory: add a common exit path to zap_huge_pmd() mm/huge_memory: handle buggy PMD entry in zap_huge_pmd() mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc mm/huge: avoid big else branch in zap_huge_pmd() mm/huge_memory: simplify vma_is_specal_huge() mm: on remap assert that input range within the proposed VMA mm: add mmap_action_map_kernel_pages[_full]() uio: replace deprecated mmap hook with mmap_prepare in uio_info drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare mm: allow handling of stacked mmap_prepare hooks in more drivers ...
2026-04-05fs: remove unncessary pagevec.h includesTal Zussman
Remove unused pagevec.h includes from .c files. These were found with the following command: grep -rl '#include.*pagevec\.h' --include='*.c' | while read f; do grep -qE 'PAGEVEC_SIZE|folio_batch' "$f" || echo "$f" done There are probably more removal candidates in .h files, but those are more complex to analyze. Link: https://lkml.kernel.org/r/20260225-pagevec_cleanup-v2-2-716868cc2d11@columbia.edu Signed-off-by: Tal Zussman <tz2294@columbia.edu> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: Chris Li <chrisl@kernel.org> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Christian Brauner <brauner@kernel.org> Cc: David Hildenbrand (Arm) <david@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-02struct dentry: make ->d_u anonymousAl Viro
Making ->d_rcu and (then) ->d_child overlapping dates back to 2006; anon unions support had been added to gcc only in 4.6 (2011) and the minimal gcc version hadn't been bumped to that until 4.19 (2018). These days there's no reason not to keep that union named. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2026-04-02for_each_alias(): helper macro for iterating through dentries of given inodeAl Viro
Most of the places using d_alias are loops iterating through all aliases for given inode; introduce a helper macro (for_each_alias(dentry, inode)) and convert open-coded instances of such loop to it. They are easier to read that way and it reduces the noise on the next steps. You _must_ hold inode->i_lock over that thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2026-03-06treewide: change inode->i_ino from unsigned long to u64Jeff Layton
On 32-bit architectures, unsigned long is only 32 bits wide, which causes 64-bit inode numbers to be silently truncated. Several filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that exceed 32 bits, and this truncation can lead to inode number collisions and other subtle bugs on 32-bit systems. Change the type of inode->i_ino from unsigned long to u64 to ensure that inode numbers are always represented as 64-bit values regardless of architecture. Update all format specifiers treewide from %lu/%lx to %llu/%llx to match the new type, along with corresponding local variable types. This is the bulk treewide conversion. Earlier patches in this series handled trace events separately to allow trace field reordering for better struct packing on 32-bit. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-09fs/nfs: Fix readdir slow-start regressionSagi Grimberg
Commit 580f236737d1 ("NFS: Adjust the amount of readahead performed by NFS readdir") reduces the amount of readahead names caching done by the client. The downside of this approach is READDIR now may suffer from a slow-start issue, where initially it will fetch names that fit in a single page, then in 2, 4, 8 until the maximum supported transfer size (usually 1M). This patch tries to take a balanced approach between mitigating the slow-start issue still maintaining some efficiency gains. Fixes: 580f236737d1 ("NFS: Adjust the amount of readahead performed by NFS readdir") Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2026-01-04NFSv4: Fix nfs_clear_verifier_delegated() for delegated directoriesTrond Myklebust
If the client returns a directory delegation, then look up all the child dentries, and clear their 'verifier delegated' bit, unless subject to a file delegation. Similarly, if a file delegation is being returned, check if there is a directory delegation before clearing a 'verifier delegated' bit. Reported-by: Christoph Hellwig <hch@lst.de> Fixes: 156b09482933 ("NFS: Request a directory delegation on ACCESS, CREATE, and UNLINK") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2026-01-04NFS: Fix directory delegation verifier checksAnna Schumaker
Doing this check in nfs_check_verifier() resulted in many, many more lookups on the wire when running Christoph's delegation benchmarking script. After some experimentation, I found that we can treat directory delegations exactly the same as having a delegated verifier when we reach nfs4_lookup_revalidate() for the best performance. Reported-by: Christoph Hellwig <hch@lst.de> Fixes: 156b09482933 ("NFS: Request a directory delegation on ACCESS, CREATE, and UNLINK") Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2025-11-23NFS: Shortcut lookup revalidations if we have a directory delegationAnna Schumaker
Holding a directory delegation means we know that nobody else has modified the directory on the server, so we can take a few revalidation shortcuts. Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2025-11-19NFS: Initialise verifiers for visible dentries in nfs_atomic_open()Trond Myklebust
Ensure that the verifiers are initialised before calling d_splice_alias() in nfs_atomic_open(). Reported-by: Michael Stoler <michael.stoler@vastdata.com> Fixes: 809fd143de88 ("NFSv4: Ensure nfs_atomic_open set the dentry verifier on ENOENT") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2025-11-19NFS: Initialise verifiers for visible dentries in readdir and lookupTrond Myklebust
Ensure that the verifiers are initialised before calling d_splice_alias() in both nfs_prime_dcache() and nfs_lookup(). Reported-by: Michael Stoler <michael.stoler@vastdata.com> Fixes: a1147b8281bd ("NFS: Fix up directory verifier races") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2025-11-17NFS: Avoid changing nlink when file removes and attribute updates raceTrond Myklebust
If a file removal races with another operation that updates its attributes, then skip the change to nlink, and just mark the attributes as being stale. Reported-by: Aiden Lambert <alambert48@gatech.edu> Fixes: 59a707b0d42e ("NFS: Ensure we revalidate the inode correctly after remove or rename") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2025-11-10NFSv2/v3: Fix error handling in nfs_atomic_open_v23()Trond Myklebust
When nfs_do_create() returns an EEXIST error, it means that a regular file could not be created. That could mean that a symlink needs to be resolved. If that's the case, a lookup needs to be kicked off. Reported-by: Stephen Abbene <sabbene87@gmail.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=220710 Fixes: 7c6c5249f061 ("NFS: add atomic_open for NFSv3 to handle O_TRUNC correctly.") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Reviewed-by: NeilBrown <neil@brown.name> Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2025-10-03Merge tag 'nfs-for-6.18-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds
Pull NFS client updates from Anna Schumaker: "New Features: - Add a Kconfig option to redirect dfprintk() to the trace buffer - Enable use of the RWF_DONTCACHE flag on the NFS client - Add striped layout handling to pNFS flexfiles - Add proper localio handling for READ and WRITE O_DIRECT Bugfixes: - Handle NFS4ERR_GRACE errors during delegation recall - Fix NFSv4.1 backchannel max_resp_sz verification check - Fix mount hang after CREATE_SESSION failure - Fix d_parent->d_inode locking in nfs4_setup_readdir() Other Cleanups and Improvements: - Improvements to write handling tracepoints - Fix a few trivial spelling mistakes - Cleanups to the rpcbind cleanup call sites - Convert the SUNRPC xdr_buf to use a scratch folio instead of scratch page - Remove unused NFS_WBACK_BUSY() macro - Remove __GFP_NOWARN flags - Unexport rpc_malloc() and rpc_free()" * tag 'nfs-for-6.18-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (46 commits) NFS: add basic STATX_DIOALIGN and STATX_DIO_READ_ALIGN support nfs/localio: add tracepoints for misaligned DIO READ and WRITE support nfs/localio: add proper O_DIRECT support for READ and WRITE nfs/localio: refactor iocb initialization nfs/localio: refactor iocb and iov_iter_bvec initialization nfs/localio: avoid issuing misaligned IO using O_DIRECT nfs/localio: make trace_nfs_local_open_fh more useful NFSD: filecache: add STATX_DIOALIGN and STATX_DIO_READ_ALIGN support sunrpc: unexport rpc_malloc() and rpc_free() NFSv4/flexfiles: Add support for striped layouts NFSv4/flexfiles: Update layout stats & error paths for striped layouts NFSv4/flexfiles: Write path updates for striped layouts NFSv4/flexfiles: Commit path updates for striped layouts NFSv4/flexfiles: Read path updates for striped layouts NFSv4/flexfiles: Update low level helper functions to be DS stripe aware. NFSv4/flexfiles: Add data structure support for striped layouts NFSv4/flexfiles: Use ds_commit_idx when marking a write commit NFSv4/flexfiles: Remove cred local variable dependency nfs4_setup_readdir(): insufficient locking for ->d_parent->d_inode dereferencing NFS: Enable use of the RWF_DONTCACHE flag on the NFS client ...
2025-09-23NFS: Update readdir to use a scratch folioAnna Schumaker
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2025-09-16slightly simplify nfs_atomic_open()Al Viro
Reviewed-by: NeilBrown <neil@brown.name> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-09-16simplify nfs_atomic_open_v23()Al Viro
1) finish_no_open() takes ERR_PTR() as dentry now. 2) caller of ->atomic_open() will call d_lookup_done() itself, no need to do it here. Reviewed-by: NeilBrown <neil@brown.name> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-07-22NFS: Fix wakeup of __nfs_lookup_revalidate() in unblock_revalidate()Trond Myklebust
Use store_release_wake_up() to add the appropriate memory barrier before calling wake_up_var(&dentry->d_fsdata). Reported-by: Lukáš Hejtmánek<xhejtman@ics.muni.cz> Suggested-by: Santosh Pradhan <santosh.pradhan@gmail.com> Link: https://lore.kernel.org/all/18945D18-3EDB-4771-B019-0335CE671077@ics.muni.cz/ Fixes: 99bc9f2eb3f7 ("NFS: add barriers when testing for NFS_FSDATA_BLOCKED") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2025-05-16NFS: Avoid flushing data while holding directory locks in nfs_rename()Trond Myklebust
The Linux client assumes that all filehandles are non-volatile for renames within the same directory (otherwise sillyrename cannot work). However, the existence of the Linux 'subtree_check' export option has meant that nfs_rename() has always assumed it needs to flush writes before attempting to rename. Since NFSv4 does allow the client to query whether or not the server exhibits this behaviour, and since knfsd does actually set the appropriate flag when 'subtree_check' is enabled on an export, it should be OK to optimise away the write flushing behaviour in the cases where it is clearly not needed. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2025-04-02Merge tag 'nfs-for-6.15-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client updates from Trond Myklebust: "Bugfixes: - Three fixes for looping in the NFSv4 state manager delegation code - Fix for the NFSv4 state XDR code (Neil Brown) - Fix a leaked reference in nfs_lock_and_join_requests() - Fix a use-after-free in the delegation return code Features: - Implement the NFSv4.2 copy offload OFFLOAD_STATUS operation to allow monitoring of an in-progress copy - Add a mount option to force NFSv3/NFSv4 to use READDIRPLUS in a getdents() call - SUNRPC now allows some basic management of an existing RPC client's connections using sysfs - Improvements to the automated teardown of a NFS client when the container it was initiated from gets killed - Improvements to prevent tasks from getting stuck in a killable wait state after calling exit_signals()" * tag 'nfs-for-6.15-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (29 commits) nfs: Add missing release on error in nfs_lock_and_join_requests() NFSv4: Check for delegation validity in nfs_start_delegation_return_locked() NFS: Don't allow waiting for exiting tasks SUNRPC: Don't allow waiting for exiting tasks NFSv4: Treat ENETUNREACH errors as fatal for state recovery NFSv4: clp->cl_cons_state < 0 signifies an invalid nfs_client NFSv4: Further cleanups to shutdown loops NFS: Shut down the nfs_client only after all the superblocks SUNRPC: rpc_clnt_set_transport() must not change the autobind setting SUNRPC: rpcbind should never reset the port to the value '0' pNFS/flexfiles: Report ENETDOWN as a connection error pNFS/flexfiles: Treat ENETUNREACH errors as fatal in containers NFS: Treat ENETUNREACH errors as fatal in containers NFS: Add a mount option to make ENETUNREACH errors fatal sunrpc: Add a sysfs file for one-step xprt deletion sunrpc: Add a sysfs file for adding a new xprt sunrpc: Add a sysfs files for rpc_clnt information sunrpc: Add a sysfs attr for xprtsec NFS: Add implid to sysfs NFS: Extend rdirplus mount option with "force|none" ...
2025-03-21NFS: Extend rdirplus mount option with "force|none"Benjamin Coddington
There are certain users that wish to force the NFS client to choose READDIRPLUS over READDIR for a particular mount. Update the "rdirplus" mount option to optionally accept values. For "rdirplus=force", the NFS client will always attempt to use READDDIRPLUS. The setting of "rdirplus=none" is aliased to the existing "nordirplus". Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Link: https://lore.kernel.org/r/c4cf0de4c8be0930b91bc74bee310d289781cd3b.1741885071.git.bcodding@redhat.com Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2025-03-05nfs: change mkdir inode_operation to return alternate dentry if needed.NeilBrown
mkdir now allows a different dentry to be returned which is sometimes relevant for nfs. This patch changes the nfs_rpc_ops mkdir op to return a dentry, and passes that back to the caller. The mkdir nfs_rpc_op will return NULL if the original dentry should be used. This matches the mkdir inode_operation. nfs4_do_create() is duplicated to nfs4_do_mkdir() which is changed to handle the specifics of directories. Consequently the current special handling for directories is removed from nfs4_do_create() Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de> Link: https://lore.kernel.org/r/20250227013949.536172-6-neilb@suse.de Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-27Change inode_operations.mkdir to return struct dentry *NeilBrown
Some filesystems, such as NFS, cifs, ceph, and fuse, do not have complete control of sequencing on the actual filesystem (e.g. on a different server) and may find that the inode created for a mkdir request already exists in the icache and dcache by the time the mkdir request returns. For example, if the filesystem is mounted twice the directory could be visible on the other mount before it is on the original mount, and a pair of name_to_handle_at(), open_by_handle_at() calls could instantiate the directory inode with an IS_ROOT() dentry before the first mkdir returns. This means that the dentry passed to ->mkdir() may not be the one that is associated with the inode after the ->mkdir() completes. Some callers need to interact with the inode after the ->mkdir completes and they currently need to perform a lookup in the (rare) case that the dentry is no longer hashed. This lookup-after-mkdir requires that the directory remains locked to avoid races. Planned future patches to lock the dentry rather than the directory will mean that this lookup cannot be performed atomically with the mkdir. To remove this barrier, this patch changes ->mkdir to return the resulting dentry if it is different from the one passed in. Possible returns are: NULL - the directory was created and no other dentry was used ERR_PTR() - an error occurred non-NULL - this other dentry was spliced in This patch only changes file-systems to return "ERR_PTR(err)" instead of "err" or equivalent transformations. Subsequent patches will make further changes to some file-systems to return a correct dentry. Not all filesystems reliably result in a positive hashed dentry: - NFS, cifs, hostfs will sometimes need to perform a lookup of the name to get inode information. Races could result in this returning something different. Note that this lookup is non-atomic which is what we are trying to avoid. Placing the lookup in filesystem code means it only happens when the filesystem has no other option. - kernfs and tracefs leave the dentry negative and the ->revalidate operation ensures that lookup will be called to correctly populate the dentry. This could be fixed but I don't think it is important to any of the users of vfs_mkdir() which look at the dentry. The recommendation to use d_drop();d_splice_alias() is ugly but fits with current practice. A planned future patch will change this. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: NeilBrown <neilb@suse.de> Link: https://lore.kernel.org/r/20250227013949.536172-2-neilb@suse.de Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-19VFS: add common error checks to lookup_one_qstr_excl()NeilBrown
Callers of lookup_one_qstr_excl() often check if the result is negative or positive. These changes can easily be moved into lookup_one_qstr_excl() by checking the lookup flags: LOOKUP_CREATE means it is NOT an error if the name doesn't exist. LOOKUP_EXCL means it IS an error if the name DOES exist. This patch adds these checks, then removes error checks from callers, and ensures that appropriate flags are passed. This subtly changes the meaning of LOOKUP_EXCL. Previously it could only accompany LOOKUP_CREATE. Now it can accompany LOOKUP_RENAME_TARGET as well. A couple of small changes are needed to accommodate this. The NFS change is functionally a no-op but ensures nfs_is_exclusive_create() does exactly what the name says. Signed-off-by: NeilBrown <neilb@suse.de> Link: https://lore.kernel.org/r/20250217003020.3170652-3-neilb@suse.de Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-01-27nfs: fix ->d_revalidate() UAF on ->d_name accessesAl Viro
Pass the stable name all the way down to ->rpc_ops->lookup() instances. Note that passing &dentry->d_name is safe in e.g. nfs_lookup() - it *is* stable there, as it is in ->create() et.al. dget_parent() in nfs_instantiate() should be redundant - it'd better be stable there; if it's not, we have more trouble, since ->d_name would also be unsafe in such case. nfs_submount() and nfs4_submount() may or may not require fixes - if they ever get moved on server with fhandle preserved, we are in trouble there... UAF window is fairly narrow here and exfiltration requires the ability to watch the traffic. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27nfs{,4}_lookup_validate(): use stable parent inode passed by callerAl Viro
we can't kill __nfs_lookup_revalidate() completely, but ->d_parent boilerplate in it is gone Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27Pass parent directory inode and expected name to ->d_revalidate()Al Viro
->d_revalidate() often needs to access dentry parent and name; that has to be done carefully, since the locking environment varies from caller to caller. We are not guaranteed that dentry in question will not be moved right under us - not unless the filesystem is such that nothing on it ever gets renamed. It can be dealt with, but that results in boilerplate code that isn't even needed - the callers normally have just found the dentry via dcache lookup and want to verify that it's in the right place; they already have the values of ->d_parent and ->d_name stable. There is a couple of exceptions (overlayfs and, to less extent, ecryptfs), but for the majority of calls that song and dance is not needed at all. It's easier to make ecryptfs and overlayfs find and pass those values if there's a ->d_revalidate() instance to be called, rather than doing that in the instances. This commit only changes the calling conventions; making use of supplied values is left to followups. NOTE: some instances need more than just the parent - things like CIFS may need to build an entire path from filesystem root, so they need more precautions than the usual boilerplate. This series doesn't do anything to that need - these filesystems have to keep their locking mechanisms (rename_lock loops, use of dentry_path_raw(), private rwsem a-la v9fs). One thing to keep in mind when using name is that name->name will normally point into the pathname being resolved; the filename in question occupies name->len bytes starting at name->name, and there is NUL somewhere after it, but it the next byte might very well be '/' rather than '\0'. Do not ignore name->len. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Gabriel Krisman Bertazi <gabriel@krisman.be> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-09-23nfs: Annotate struct nfs_cache_array with __counted_by()Thorsten Blum
Add the __counted_by compiler attribute to the flexible array member array to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE. Increment size before adding a new struct to the array. Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com> Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-07-08NFSv4: Add a flags argument to the 'have_delegation' callbackTrond Myklebust
This argument will be used to allow the caller to specify whether or not they need to know that this is an attribute delegation. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2024-05-30NFS: add barriers when testing for NFS_FSDATA_BLOCKEDNeilBrown
dentry->d_fsdata is set to NFS_FSDATA_BLOCKED while unlinking or renaming-over a file to ensure that no open succeeds while the NFS operation progressed on the server. Setting dentry->d_fsdata to NFS_FSDATA_BLOCKED is done under ->d_lock after checking the refcount is not elevated. Any attempt to open the file (through that name) will go through lookp_open() which will take ->d_lock while incrementing the refcount, we can be sure that once the new value is set, __nfs_lookup_revalidate() *will* see the new value and will block. We don't have any locking guarantee that when we set ->d_fsdata to NULL, the wait_var_event() in __nfs_lookup_revalidate() will notice. wait/wake primitives do NOT provide barriers to guarantee order. We must use smp_load_acquire() in wait_var_event() to ensure we look at an up-to-date value, and must use smp_store_release() before wake_up_var(). This patch adds those barrier functions and factors out block_revalidate() and unblock_revalidate() far clarity. There is also a hypothetical bug in that if memory allocation fails (which never happens in practice) we might leave ->d_fsdata locked. This patch adds the missing call to unblock_revalidate(). Reported-and-tested-by: Richard Kojedzinszky <richard+debian+bugreport@kojedz.in> Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1071501 Fixes: 3c59366c207e ("NFS: don't unhash dentry during unlink/rename") Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2024-05-30NFS: abort nfs_atomic_open_v23 if name is too long.NeilBrown
An attempt to open a file with a name longer than NFS3_MAXNAMLEN will trigger a WARN_ON_ONCE in encode_filename3() because nfs_atomic_open_v23() doesn't have the test on ->d_name.len that nfs_atomic_open() has. So add that test. Reported-by: James Clark <james.clark@arm.com> Closes: https://lore.kernel.org/all/20240528105249.69200-1-james.clark@arm.com/ Fixes: 7c6c5249f061 ("NFS: add atomic_open for NFSv3 to handle O_TRUNC correctly.") Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2024-05-24nfs: don't invalidate dentries on transient errorsScott Mayhew
This is a slight variation on a patch previously proposed by Neil Brown that never got merged. Prior to commit 5ceb9d7fdaaf ("NFS: Refactor nfs_lookup_revalidate()"), any error from nfs_lookup_verify_inode() other than -ESTALE would result in nfs_lookup_revalidate() returning that error (-ESTALE is mapped to zero). Since that commit, all errors result in nfs_lookup_revalidate() returning zero, resulting in dentries being invalidated where they previously were not (particularly in the case of -ERESTARTSYS). Fix it by passing the actual error code to nfs_lookup_revalidate_done(), and leaving the decision on whether to map the error code to zero or one to nfs_lookup_revalidate_done(). A simple reproducer is to run the following python code in a subdirectory of an NFS mount (not in the root of the NFS mount): ---8<--- import os import multiprocessing import time if __name__=="__main__": multiprocessing.set_start_method("spawn") count = 0 while True: try: os.getcwd() pool = multiprocessing.Pool(10) pool.close() pool.terminate() count += 1 except Exception as e: print(f"Failed after {count} iterations") print(e) break ---8<--- Prior to commit 5ceb9d7fdaaf, the above code would run indefinitely. After commit 5ceb9d7fdaaf, it fails almost immediately with -ENOENT. Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2024-05-20NFS: add atomic_open for NFSv3 to handle O_TRUNC correctly.NeilBrown
With two clients, each with NFSv3 mounts of the same directory, the sequence: client1 client2 ls -l afile echo hello there > afile echo HELLO > afile cat afile will show HELLO there because the O_TRUNC requested in the final 'echo' doesn't take effect. This is because the "Negative dentry, just create a file" section in lookup_open() assumes that the file *does* get created since the dentry was negative, so it sets FMODE_CREATED, and this causes do_open() to clear O_TRUNC and so the file doesn't get truncated. Even mounting with -o lookupcache=none does not help as nfs_neg_need_reval() always returns false if LOOKUP_CREATE is set. This patch fixes the problem by providing an atomic_open inode operation for NFSv3 (and v2). The code is largely the code from the branch in lookup_open() when atomic_open is not provided. The significant change is that the O_TRUNC flag is passed a new nfs_do_create() which add 'trunc' handling to nfs_create(). With this change we also optimise away an unnecessary LOOKUP before the file is created. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2024-02-25nfs: make nfs_set_verifier() safe for use in RCU pathwalkAl Viro
nfs_set_verifier() relies upon dentry being pinned; if that's the case, grabbing ->d_lock stabilizes ->d_parent and guarantees that ->d_parent points to a positive dentry. For something we'd run into in RCU mode that is *not* true - dentry might've been through dentry_kill() just as we grabbed ->d_lock, with its parent going through the same just as we get to into nfs_set_verifier_locked(). It might get to detaching inode (and zeroing ->d_inode) before nfs_set_verifier_locked() gets to fetching that; we get an oops as the result. That can happen in nfs{,4} ->d_revalidate(); the call chain in question is nfs_set_verifier_locked() <- nfs_set_verifier() <- nfs_lookup_revalidate_delegated() <- nfs{,4}_do_lookup_revalidate(). We have checked that the parent had been positive, but that's done before we get to nfs_set_verifier() and it's possible for memory pressure to pick our dentry as eviction candidate by that time. If that happens, back-to-back attempts to kill dentry and its parent are quite normal. Sure, in case of eviction we'll fail the ->d_seq check in the caller, but we need to survive until we return there... Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-01-04nfs: add new tracepoint at nfs4 revalidate entry pointJeff Layton
Add a call to the v4 d_revalidate entrypoint, just like the v3 one. Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2024-01-04NFS: Use parent's objective cred in nfs_access_login_time()Scott Mayhew
The subjective cred (task->cred) can potentially be overridden and subsquently freed in non-RCU context, which could lead to a panic if we try to use it in cred_fscmp(). Use __task_cred(), which returns the objective cred (task->real_cred) instead. Fixes: 0eb43812c027 ("NFS: Clear the file access cache upon login") Fixes: 5e9a7b9c2ea1 ("NFS: Fix up a sparse warning") Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-11-01nfs: Convert nfs_symlink() to use a folioMatthew Wilcox (Oracle)
Use the folio APIs, saving about four calls to compound_head(). Convert back to a page in each of the individual protocol implementations. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2023-08-24nfs: fix redundant readdir request after get eofKinglong Mee
When a directory contains 17 files (except . and ..), nfs client sends a redundant readdir request after get eof. A simple reproduce, At NFS server, create a directory with 17 files under exported directory. # mkdir test # cd test # for i in {0..16} ; do touch $i; done At NFS client, no matter mounting through nfsv3 or nfsv4, does ls (or ll) at the created test directory. A tshark output likes following (for nfsv4), # tshark -i eth0 tcp port 2049 -Tfields -e ip.src -e ip.dst -e nfs -e nfs.cookie4 srcip dstip SEQUENCE, PUTFH, READDIR 0 dstip srcip SEQUENCE PUTFH READDIR 909539109313539306,2108391201987888856,2305312124304486544,2566335452463141496,2978225129081509984,4263037479923412583,4304697173036510679,4666703455469210097,4759208201298769007,4776701232145978803,5338408478512081262,5949498658935544804,5971526429894832903,6294060338267709855,6528840566229532529,8600463293536422524,9223372036854775807 srcip dstip srcip dstip SEQUENCE, PUTFH, READDIR 9223372036854775807 dstip srcip SEQUENCE PUTFH READDIR The READDIR with cookie 9223372036854775807(0x7FFFFFFFFFFFFFFF) is redundant. Reviewed-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-05-19NFS: Convert kmap_atomic() to kmap_local_folio()Fabio M. De Francesco
kmap_atomic() is deprecated in favor of kmap_local_{folio,page}(). Therefore, replace kmap_atomic() with kmap_local_folio() in nfs_readdir_folio_array_append(). kmap_atomic() disables page-faults and preemption (the latter only for !PREEMPT_RT kernels), However, the code within the mapping/un-mapping in nfs_readdir_folio_array_append() does not depend on the above-mentioned side effects. Therefore, a mere replacement of the old API with the new one is all that is required (i.e., there is no need to explicitly add any calls to pagefault_disable() and/or preempt_disable()). Tested with (x)fstests in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with HIGHMEM64GB enabled. Cc: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Fixes: ec108d3cc766 ("NFS: Convert readdir page array functions to use a folio") Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>