kernel/linux.git/fs/overlayfs/util.c, branch v6.19.11

ovl: fix wrong detection of 32bit inode numbers

2026-04-02T11:25:44+00:00

commit 53a7c171e9dd833f0a96b545adcb89bd57387239 upstream. The implicit FILEID_INO32_GEN encoder was changed to be explicit, so we need to fix the detection. When mounting overlayfs with upperdir and lowerdir on different ext4 filesystems, the expected kmsg log is: overlayfs: "xino" feature enabled using 32 upper inode bits. But instead, since the regressing commit, the kmsg log was: overlayfs: "xino" feature enabled using 2 upper inode bits. Fixes: e21fc2038c1b9 ("exportfs: make ->encode_fh() a mandatory method for NFS export") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Amir Goldstein Signed-off-by: Greg Kroah-Hartman

Merge tag 'vfs-6.19-rc1.ovl' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-02T00:31:21+00:00

Pull overlayfs cred guard conversion from Christian Brauner: "This converts all of overlayfs to use credential guards, eliminating manual credential management throughout the filesystem. Credential guard conversion: - Convert all of overlayfs to use credential guards, replacing the manual ovl_override_creds()/ovl_revert_creds() pattern with scoped guards. This makes credential handling visually explicit and eliminates a class of potential bugs from mismatched override/revert calls. (1) Basic credential guard (with_ovl_creds) (2) Creator credential guard (ovl_override_creator_creds): Introduced a specialized guard for file creation operations that handles the two-phase credential override (mounter credentials, then fs{g,u}id override). The new pattern is much clearer: with_ovl_creds(dentry->d_sb) { scoped_class(prepare_creds_ovl, cred, dentry, inode, mode) { if (IS_ERR(cred)) return PTR_ERR(cred); /* creation operations */ } } (3) Copy-up credential guard (ovl_cu_creds): Introduced a specialized guard for copy-up operations, simplifying the previous struct ovl_cu_creds helper and associated functions. Ported ovl_copy_up_workdir() and ovl_copy_up_tmpfile() to this pattern. Cleanups: - Remove ovl_revert_creds() after all callers converted to guards - Remove struct ovl_cu_creds and associated functions - Drop ovl_setup_cred_for_create() after conversion - Refactor ovl_fill_super(), ovl_lookup(), ovl_iterate(), ovl_rename() for cleaner credential guard scope - Introduce struct ovl_renamedata to simplify rename handling - Don't override credentials for ovl_check_whiteouts() (unnecessary) - Remove unneeded semicolon" * tag 'vfs-6.19-rc1.ovl' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (54 commits) ovl: remove unneeded semicolon ovl: remove struct ovl_cu_creds and associated functions ovl: port ovl_copy_up_tmpfile() to cred guard ovl: mark *_cu_creds() as unused temporarily ovl: port ovl_copy_up_workdir() to cred guard ovl: add copy up credential guard ovl: drop ovl_setup_cred_for_create() ovl: port ovl_create_or_link() to new ovl_override_creator_creds cleanup guard ovl: mark ovl_setup_cred_for_create() as unused temporarily ovl: reflow ovl_create_or_link() ovl: port ovl_create_tmpfile() to new ovl_override_creator_creds cleanup guard ovl: add ovl_override_creator_creds cred guard ovl: remove ovl_revert_creds() ovl: port ovl_fill_super() to cred guard ovl: refactor ovl_fill_super() ovl: port ovl_lower_positive() to cred guard ovl: port ovl_lookup() to cred guard ovl: refactor ovl_lookup() ovl: port ovl_copyfile() to cred guard ovl: port ovl_rename() to cred guard ...

Merge tag 'vfs-6.19-rc1.directory.locking' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-02T00:13:46+00:00

Pull directory locking updates from Christian Brauner: "This contains the work to add centralized APIs for directory locking operations. This series is part of a larger effort to change directory operation locking to allow multiple concurrent operations in a directory. The ultimate goal is to lock the target dentry(s) rather than the whole parent directory. To help with changing the locking protocol, this series centralizes locking and lookup in new helper functions. The helpers establish a pattern where it is the dentry that is being locked and unlocked (currently the lock is held on dentry->d_parent->d_inode, but that can change in the future). This also changes vfs_mkdir() to unlock the parent on failure, as well as dput()ing the dentry. This allows end_creating() to only require the target dentry (which may be IS_ERR() after vfs_mkdir()), not the parent" * tag 'vfs-6.19-rc1.directory.locking' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: nfsd: fix end_creating() conversion VFS: introduce end_creating_keep() VFS: change vfs_mkdir() to unlock on failure. ecryptfs: use new start_creating/start_removing APIs Add start_renaming_two_dentries() VFS/ovl/smb: introduce start_renaming_dentry() VFS/nfsd/ovl: introduce start_renaming() and end_renaming() VFS: add start_creating_killable() and start_removing_killable() VFS: introduce start_removing_dentry() smb/server: use end_removing_noperm for for target of smb2_create_link() VFS: introduce start_creating_noperm() and start_removing_noperm() VFS/nfsd/cachefiles/ovl: introduce start_removing() and end_removing() VFS/nfsd/cachefiles/ovl: add start_creating() and end_creating() VFS: tidy up do_unlinkat() VFS: introduce start_dirop() and end_dirop() debugfs: rename end_creating() to debugfs_end_creating()

Merge tag 'vfs-6.19-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-01T17:02:34+00:00

Pull vfs inode updates from Christian Brauner: "Features: - Hide inode->i_state behind accessors. Open-coded accesses prevent asserting they are done correctly. One obvious aspect is locking, but significantly more can be checked. For example it can be detected when the code is clearing flags which are already missing, or is setting flags when it is illegal (e.g., I_FREEING when ->i_count > 0) - Provide accessors for ->i_state, converts all filesystems using coccinelle and manual conversions (btrfs, ceph, smb, f2fs, gfs2, overlayfs, nilfs2, xfs), and makes plain ->i_state access fail to compile - Rework I_NEW handling to operate without fences, simplifying the code after the accessor infrastructure is in place Cleanups: - Move wait_on_inode() from writeback.h to fs.h - Spell out fenced ->i_state accesses with explicit smp_wmb/smp_rmb for clarity - Cosmetic fixes to LRU handling - Push list presence check into inode_io_list_del() - Touch up predicts in __d_lookup_rcu() - ocfs2: retire ocfs2_drop_inode() and I_WILL_FREE usage - Assert on ->i_count in iput_final() - Assert ->i_lock held in __iget() Fixes: - Add missing fences to I_NEW handling" * tag 'vfs-6.19-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (22 commits) dcache: touch up predicts in __d_lookup_rcu() fs: push list presence check into inode_io_list_del() fs: cosmetic fixes to lru handling fs: rework I_NEW handling to operate without fences fs: make plain ->i_state access fail to compile xfs: use the new ->i_state accessors nilfs2: use the new ->i_state accessors overlayfs: use the new ->i_state accessors gfs2: use the new ->i_state accessors f2fs: use the new ->i_state accessors smb: use the new ->i_state accessors ceph: use the new ->i_state accessors btrfs: use the new ->i_state accessors Manual conversion to use ->i_state accessors of all places not covered by coccinelle Coccinelle-based conversion to use ->i_state accessors fs: provide accessors for ->i_state fs: spell out fenced ->i_state accesses with explicit smp_wmb/smp_rmb fs: move wait_on_inode() from writeback.h to fs.h fs: add missing fences to I_NEW handling ocfs2: retire ocfs2_drop_inode() and I_WILL_FREE usage ...

ovl: fail ovl_lock_rename_workdir() if either target is unhashed

2025-11-28T09:42:32+00:00

As well as checking that the parent hasn't changed after getting the lock we need to check that the dentry hasn't been unhashed. Otherwise we might try to rename something that has been removed. Reported-by: syzbot+bfc9a0ccf0de47d04e8c@syzkaller.appspotmail.com Fixes: d2c995581c7c ("ovl: Call ovl_create_temp() without lock held.") Signed-off-by: NeilBrown Link: https://patch.msgid.link/176429295510.634289.1552337113663461690@noble.neil.brown.name Tested-by: syzbot+bfc9a0ccf0de47d04e8c@syzkaller.appspotmail.com Reviewed-by: Amir Goldstein Signed-off-by: Christian Brauner

ovl: remove ovl_revert_creds()

2025-11-19T20:58:25+00:00

The wrapper isn't needed anymore. Overlayfs completely relies on its cleanup guard. Link: https://patch.msgid.link/20251117-work-ovl-cred-guard-v4-42-b31603935724@kernel.org Reviewed-by: Amir Goldstein Signed-off-by: Christian Brauner

ovl: port ovl_nlink_end() to cred guard

2025-11-19T20:58:23+00:00

Use the scoped ovl cred guard. Link: https://patch.msgid.link/20251117-work-ovl-cred-guard-v4-29-b31603935724@kernel.org Reviewed-by: Amir Goldstein Signed-off-by: Christian Brauner

ovl: port ovl_nlink_start() to cred guard

2025-11-19T20:58:23+00:00

Use the scoped ovl cred guard. Link: https://patch.msgid.link/20251117-work-ovl-cred-guard-v4-28-b31603935724@kernel.org Reviewed-by: Amir Goldstein Signed-off-by: Christian Brauner

VFS/ovl/smb: introduce start_renaming_dentry()

2025-11-14T12:15:57+00:00

Several callers perform a rename on a dentry they already have, and only require lookup for the target name. This includes smb/server and a few different places in overlayfs. start_renaming_dentry() performs the required lookup and takes the required lock using lock_rename_child() It is used in three places in overlayfs and in ksmbd_vfs_rename(). In the ksmbd case, the parent of the source is not important - the source must be renamed from wherever it is. So start_renaming_dentry() allows rd->old_parent to be NULL and only checks it if it is non-NULL. On success rd->old_parent will be the parent of old_dentry with an extra reference taken. Other start_renaming function also now take the extra reference and end_renaming() now drops this reference as well. ovl_lookup_temp(), ovl_parent_lock(), and ovl_parent_unlock() are all removed as they are no longer needed. OVL_TEMPNAME_SIZE and ovl_tempname() are now declared in overlayfs.h so that ovl_check_rename_whiteout() can access them. ovl_copy_up_workdir() now always cleans up on error. Reviewed-by: Namjae Jeon Reviewed-by: Amir Goldstein Reviewed-by: Jeff Layton Signed-off-by: NeilBrown Link: https://patch.msgid.link/20251113002050.676694-12-neilb@ownmail.net Tested-by: syzbot@syzkaller.appspotmail.com Signed-off-by: Christian Brauner

overlayfs: use the new ->i_state accessors

2025-10-20T18:22:27+00:00

Change generated with coccinelle and fixed up by hand as appropriate. Signed-off-by: Mateusz Guzik Signed-off-by: Christian Brauner