summaryrefslogtreecommitdiff
path: root/fs/overlayfs
AgeCommit message (Collapse)Author
4 daystreewide: refresh kmalloc_obj() conversionsKees Cook
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-08-17Merge tag 'vfs-7.3-rc1.ovl' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull overlayfs updates from Christian Brauner: "This lets the merged overlayfs mount itself be idmapped through mount_setattr(MOUNT_ATTR_IDMAP), in addition to the already supported idmapped lower and upper layers. The same overlay tree can then be exposed under a different ownership view. Overlayfs already normalizes every underlying id through the relevant layer idmap when ovl_copyattr() copies attributes into the overlay inode. So the overlay inode's i_uid and i_gid are overlay-final ids. The overlay mount idmap composes on top of that and is applied at the overlay-inode boundary only while the underlying layers keep being accessed with the mounter's credentials through their own (possibly idmapped) mounts. So this only changes how the caller sees the overlay inode and never widens the mounter's access to the layers. The second, mounter-credential check in ovl_permission() against the real inode stays on the layer idmap. Most paths need no change because the VFS applies the mount idmap to the overlay inode before overlayfs runs or after it returns at the syscall boundary. Overlayfs only has to change where it bypasses the generic path. This also included is a fix for a double end_creating() on the overlayfs casefold-mismatch path" * tag 'vfs-7.3-rc1.ovl' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: ovl: fix double end_creating() on the casefold-mismatch path ovl: document security.capability idmapping on the xattr forward paths selftests/filesystems/overlayfs: test idmapped overlay mounts selftests/filesystems/overlayfs: fix set_layers_via_fds link error docs: document idmapped overlay mounts ovl: allow idmapping overlay mounts ovl: handle idmapped mounts in ovl_set_acl() ovl: handle idmapped mounts in ovl_getattr() ovl: handle idmapped mounts in ovl_setattr() ovl: handle idmapped mounts in ovl_permission() ovl: handle idmapped mounts in ovl_create_object() and ovl_tmpfile()
2026-08-17Merge tag 'vfs-7.3-rc1.lookup' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs lookup updates from Christian Brauner: "This refactors lookup_open() and adds vfs_lookup_open() for nfsd. mnt_want_write() and parent locking are moved into lookup_open() itself. audit_inode_child() is also now called in lookup_open() on failure. That is the calling convention in vfs_create() and vfs_mkdir(), but lookup_open() made no such call when atomic_open() should have created a file and did not. And neither did the regular ->create() path fwiw. This also contains work to remove the unneeded excl argument from the ->create() inode op" * tag 'vfs-7.3-rc1.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs/namei.c: fix coding style in atomic_open() and lookup_open() fs/namei.c: fix kerneldoc of atomic_open() and vfs_lookup_open() fs/namei.c: update stale comments in lookup_open() Remove excl arg to ->create inode_operation fs/namei.c: update kerneldoc of atomic_open() vfs: call audit_inode_child() in lookup_open() on failure vfs: move create error && negative dentry case in lookup_open() up VFS: add vfs_lookup_open() for nfsd VFS: move delegated_inode retry loop into lookup_open() VFS: move mnt_want_write() and locking into lookup_open()
2026-08-12ovl: fix double end_creating() on the casefold-mismatch pathVivek Parikh
ovl_create_real() releases the new dentry twice when the casefold consistency check fails. The S_IFDIR branch calls end_creating() and sets err, then falls through to the common out: label which calls end_creating() on the same dentry again: case S_IFDIR: newdentry = ovl_do_mkdir(ofs, dir, newdentry, attr->mode); err = PTR_ERR_OR_ZERO(newdentry); if (!err && ofs->casefold != ovl_dentry_casefolded(newdentry)) { pr_warn_ratelimited(...); end_creating(newdentry); /* first */ err = -EINVAL; } break; ... if (err) goto out; ... out: if (err) { end_creating(newdentry); /* second, same dentry */ return ERR_PTR(err); } end_creating() is end_dirop(), which does inode_unlock() on the parent and dput() on the dentry, so the parent directory's i_rwsem is unlocked twice and the dentry is put twice. The second unlock releases a lock that is not held, which is what wedges every later creation under that parent, and the second dput() drops a reference that was never taken. The branch was added by commit dfc7da402ccc ("ovl: Check for casefold consistency when creating new dentries") as a bare dput(), which already released the reference twice; commit fe497f0759e0 ("VFS: change vfs_mkdir() to unlock on failure.") converted both sites to end_creating(), adding the double unlock. This is reachable by an unprivileged user. The casefold consistency of the layers is validated at mount time in ovl_parse_layer(), and again on every lookup in ovl_lookup_single(), but ofs->workdir is the internal "work" subdirectory created inside the user-supplied workdir, and that subdirectory is not re-checked. Marking it casefolded after the mount therefore makes every ovl_create_temp() inherit the wrong state - and that path reaches ovl_create_real() through ovl_start_creating_temp(), which uses start_creating() with a generated name and so never runs the lookup-time check. unshare -Urm mount -t tmpfs -o casefold=utf8-12.1.0 tmpfs mnt mkdir -p mnt/lower/d mnt/upper mnt/work mnt/merged mount -t overlay ovl -o lowerdir=mnt/lower,\ upperdir=mnt/upper,workdir=mnt/work mnt/merged chattr +F mnt/work/work mkdir mnt/merged/d/sub # directory copy-up overlayfs: wrong inherited casefold (work/#5) and the next copy-up blocks forever on the parent's i_rwsem: mkdir D start_creating+0x65/0xb0 ovl_start_creating_temp+0xb0/0xe0 [overlay] ovl_create_temp+0xa3/0x1d0 [overlay] ovl_copy_up_one+0x1f1c/0x21c0 [overlay] ovl_copy_up_flags+0xf5/0x140 [overlay] ovl_create_object+0xb7/0x220 [overlay] ovl_mkdir+0x23/0x40 [overlay] Drop the end_creating() from the branch and let out: own the cleanup, which is what every other error path in this function already does. Fixes: dfc7da402ccc ("ovl: Check for casefold consistency when creating new dentries") Cc: stable@vger.kernel.org Signed-off-by: Vivek Parikh <vivek.parikh@breachx.ai> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-08-10ovl: don't warn when the mount is completed from another user namespaceChristian Brauner
fsopen() records the caller's user namespace in fc->user_ns and hands back an ordinary file descriptor. Nothing ties the task that calls fsconfig(FSCONFIG_CMD_CREATE) to the task that created the context. The fd is inherited across fork() and exec() and it can be passed over a unix socket. Completing a context from another user namespace is allowed on purpose. vfs_cmd_create() authorizes the create with mount_capable(), which for FS_USERNS_MOUNT checks ns_capable(fc->user_ns, CAP_SYS_ADMIN), and that succeeds for a task holding CAP_SYS_ADMIN in an ancestor of fc->user_ns. So an unprivileged task can reach the WARN_ON() in ovl_fill_super(): create a user and a mount namespace in a child, call fsopen("overlay") there, send the fscontext fd to the parent and let the parent issue FSCONFIG_CMD_CREATE. Both namespaces come from a plain unshare(1) and no capability is needed anywhere: WARNING: fs/overlayfs/super.c:1551 at ovl_fill_super+0x7b9/0x1e20 [overlay] CPU: 3 UID: 1000 PID: 3243376 Comm: fswarn Call Trace: get_tree_nodev+0x71/0xa0 ovl_get_tree+0x15/0x20 [overlay] vfs_get_tree+0x2a/0x100 vfs_cmd_create+0x60/0xf0 __do_sys_fsconfig+0x4b2/0x500 The child needs the mount namespace because fsopen() itself gates on may_mount(), which asks for CAP_SYS_ADMIN in the user namespace owning the caller's mount namespace. fsconfig() doesn't repeat that check. It is a WARN_ON() and not a WARN_ON_ONCE(), so the condition can be raised in a loop to taint the kernel and flood the log, and it panics a kernel booted with panic_on_warn. Keep refusing the mount and stop warning about it. ovl_parse_param() already spells a user namespace check this way for Opt_override_creds. Fixes: 1784fbc2ed9c ("ovl: port to new mount api") Cc: stable@vger.kernel.org # v6.5+ Link: https://patch.msgid.link/20260802-work-fill_super-warn-v1-1-4e987911a39a@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-31Remove excl arg to ->create inode_operationNeilBrown
The only time that 'false' is passed as the 'excl' arg to the ->create inode_operation is in lookup_open() when ->atomic_open is not provided by the parent directory. *all* directory inode_operations which do not have ->atomic_open completely ignore the 'excl' arg. Therefore we don't need the 'excl' arg. Those few ->create operations which pay attention to the arg are only ever called with a value of 'true'. We remove that arg and change all ->create operations to behave as those thhe arg were 'true'. Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/178290671516.27465.15984496764174914338@noble.neil.brown.name Reviewed-by: Jori Koolstra <jkoolstra@xs4all.nl> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-22ovl: check access to copy_file_range source with src mounter credsAmir Goldstein
Commit 5dae222a5ff0c ("vfs: allow copy_file_range to copy across devices") allowed filesystems that implement the copy_file_range() f_op to decide if they want to access cross-sb copy from/to the same fs type. The same commit added checks to verify same sb copy for filesystems that implement ->copy_file_range() and do not support cross-sb copy at the time, namely, to ceph, fuse and nfs. The two remaining fs which implement ->copy_file_range(), cifs and overlayfs started to support cross-sb copy from this time. While overlayfs does support cross-sb copy when the two underlying files are on the same base fs, the copy operation on the two real files from two different overalyfs filesystems is performed with the mounter creds of the destination overlayfs and the read permission access hook for the source file was called with the wrong creds. This could cause either deny of access to copy which would otherwise be allowed (e.g. with splice) or allow read access to file which would otherwise be denied. Fix the latter case by explicitly verifying read access to source file with the source overlayfs mounter creds. The former case remains a quirk of cross-sb overlayfs copy, but userspace could fall back to regular copy so no harm done. Fixes: 5dae222a5ff0c ("vfs: allow copy_file_range to copy across devices") Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://patch.msgid.link/20260712122421.203113-1-amir73il@gmail.com Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-22ovl: fix trusted xattr escape prefix matchingYichong Chen
In the trusted.* xattr namespace, ovl_is_escaped_xattr() compares one byte less than the escaped overlay xattr prefix length. This makes it match "trusted.overlay.overlay" without requiring the trailing dot. As a result, an xattr such as "trusted.overlay.overlayfoo" is incorrectly treated as an escaped overlay xattr. This can be reproduced by setting "trusted.overlay.overlayfoo" on a lower file and listing xattrs through an overlay mount. listxattr() then exposes it as "trusted.overlay.oo", and a following getxattr() on that listed name fails with ENODATA. Compare the full escaped prefix, including the trailing dot, so similarly-prefixed private xattrs are not misclassified. Fixes: dad02fad84cbc ("ovl: Support escaped overlay.* xattrs") Signed-off-by: Yichong Chen <chenyichong@uniontech.com> Link: https://patch.msgid.link/20260708082221.633602-1-chenyichong@uniontech.com Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-01ovl: fix comment about locking orderAmir Goldstein
Forgot to update the comment when we changed the locking order. Fixes: 162d06444070c ("ovl: reorder ovl_want_write() after ovl_inode_lock()") Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://patch.msgid.link/20260609184656.1916631-1-amir73il@gmail.com Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-01ovl: use linked upper dentry in copy-up tmpfileSouvik Banerjee
ovl_copy_up_tmpfile() stores the disconnected O_TMPFILE dentry as the overlay's upper dentry reference via ovl_inode_update(). vfs_tmpfile() allocated this dentry via d_alloc(parentpath->dentry, &slash_name), so d_name is "/" and d_parent is c->workdir. Local upper filesystems (ext4, btrfs, xfs, ...) immediately rename it to "#<inum>" via d_mark_tmpfile() inside their ->tmpfile() op; FUSE and virtiofs do not, so both fields stay that way. Neither identifies the destination directory and filename where ovl_do_link() actually linked the file. When the upper filesystem implements ->d_revalidate() (e.g. FUSE or virtiofs), ovl_revalidate_real() calls it with the dentry's parent inode and a snapshot of d_name. The server tries to look up "/" inside c->workdir, fails, and overlayfs reports -ESTALE. This causes persistent ESTALE errors for any file that was copied up via the tmpfile path, breaking dpkg, apt, and other tools that do rename-over-existing on overlayfs with a FUSE/virtiofs upper. Before commit 6b52243f633e ("ovl: fold copy-up helpers into callers"), the tmpfile copy-up path used a dedicated helper ovl_link_tmpfile() that captured the linked destination dentry returned by ovl_do_link(): err = ovl_do_link(temp, udir, upper); ... if (!err) *newdentry = dget(upper); and published it via ovl_inode_update(d_inode(c->dentry), newdentry). The fold inlined ovl_do_link() into ovl_copy_up_tmpfile() but dropped the dget(upper) capture, and rewrote the publish line as ovl_inode_update(d_inode(c->dentry), dget(temp)) — where temp is the disconnected O_TMPFILE dentry. Fix by keeping a reference to the linked destination dentry after ovl_do_link() succeeds, and publishing that dentry at the existing ovl_inode_update() call site. The non-tmpfile/workdir path continues to publish the renamed temporary dentry. Reproducer: - Mount overlayfs with virtiofs (or a FUSE fs whose server advertises FUSE_TMPFILE) as upper - Run: dpkg -i <any .deb> - Observe: "error installing new file '...': Stale file handle" Fixes: 6b52243f633e ("ovl: fold copy-up helpers into callers") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Souvik Banerjee <souvik@amlalabs.com> Link: https://patch.msgid.link/20260501232735.2610824-1-souvik@amlalabs.com Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29ovl: document security.capability idmapping on the xattr forward pathsChristian Brauner
Now that an overlay mount can itself be idmapped, every id exposed at the overlay-inode boundary is mapped through the overlay mount idmap. security.capability is the one id-bearing xattr that overlayfs does not translate in its own boundary code: the embedded rootid of a v3 fscap is instead mapped by the capability LSM inside vfs_getxattr() and vfs_setxattr(). It still composes correctly only because the xattr read and write forwards go through the security-aware vfs_getxattr() / vfs_setxattr() rather than the raw __vfs_*xattr() variants: commoncap maps the rootid through the layer idmap at the overlay-to-real forward, while the overlay mount idmap is applied by the outer vfs_getxattr() at the syscall boundary, mirroring the layer-then-mount composition used by ovl_getattr(). The raw __vfs_*xattr() variants skip the security hooks and would silently drop the rootid mapping. Comment both forwards - the read in ovl_xattr_get() and the write in ovl_do_setxattr() - so they are not converted to them by accident. No functional change. Link: https://patch.msgid.link/20260615-work-idmapped-overlayfs-v1-10-7381632aa402@kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29ovl: allow idmapping overlay mountsChristian Brauner
Now that every overlay inode operation honors the overlay mount idmap, allow the merged overlay mount itself to be idmapped by setting FS_ALLOW_IDMAP on ovl_fs_type. mount_setattr(MOUNT_ATTR_IDMAP) can then apply an idmapping to an overlay mount, exposing the merged tree under a different ownership view. The composition is clean because overlayfs already normalizes every underlying id through the relevant layer idmap when it copies attributes into the overlay inode (ovl_copyattr()); the overlay inode's i_{u,g}id are thus "overlay-final" ids. The overlay mount idmap composes on top of that pivot: it is applied to (getattr) and removed from (setattr, create) those ids at the overlay-inode boundary - permission, getattr, setattr, ACL owner checks and inode_init_owner() - while the underlying layers keep being accessed with the mounter's credentials through their own, possibly idmapped, mounts. The mount idmap therefore only changes how the caller sees the overlay inode and never widens the mounter's access to the layers. This is deliberately the final code patch of the series: only once every operation honors the mount idmap is it safe to make overlay mounts idmappable. Link: https://patch.msgid.link/20260615-work-idmapped-overlayfs-v1-6-7381632aa402@kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29ovl: handle idmapped mounts in ovl_set_acl()Christian Brauner
The two checks ovl_set_acl() performs on the overlay inode itself - inode_owner_or_capable() and the setgid-stripping test - were done with &nop_mnt_idmap. On an idmapped overlay mount this compares the overlay inode's id space directly against the caller's: it denies the rightful owner (as seen through the mount idmap) the right to set an ACL, and evaluates the setgid-drop decision in the wrong id space, which can mis-set the mode on the upper inode. Use the struct mnt_idmap passed in by the VFS for both. Fold the open-coded "caller not in group and not CAP_FSETID privileged" test into in_group_or_capable() with i_gid_into_vfsgid(), the same idmap-aware helpers used by setattr_should_drop_sgid(). The subsequent internal forced setgid-kill via ovl_setattr() stays on &nop_mnt_idmap: it carries only ATTR_KILL_SGID with no uid/gid to translate and is overlayfs' own mode change, not a user-driven operation through the mount. No functional change until FS_ALLOW_IDMAP is set on ovl_fs_type. Link: https://patch.msgid.link/20260615-work-idmapped-overlayfs-v1-5-7381632aa402@kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29ovl: handle idmapped mounts in ovl_getattr()Christian Brauner
ovl_getattr() fetches attributes from the real (upper or lower) path via vfs_getattr(), so the returned stat->uid/stat->gid are already mapped through the real layer idmap but not through the overlay mount idmap. Unlike the generic path, the VFS does not re-apply the accessing mount's idmap after ->getattr returns - generic_fillattr() does it, but overlayfs bypasses it - so overlayfs has to do it itself. Map stat->uid/stat->gid through the overlay mount idmap before returning, mirroring generic_fillattr(). The owner reported through an idmapped overlay mount is thus the overlay-final id translated by the mount idmap. No functional change until FS_ALLOW_IDMAP is set on ovl_fs_type; until then make_vfsuid()/make_vfsgid() are the identity for &nop_mnt_idmap. Link: https://patch.msgid.link/20260615-work-idmapped-overlayfs-v1-4-7381632aa402@kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29ovl: handle idmapped mounts in ovl_setattr()Christian Brauner
Pass the mount's struct mnt_idmap to setattr_prepare() so that the permission checks for a chown/chmod performed through an idmapped overlay mount are evaluated in the mount's id space. The ownership requested in @attr is expressed relative to the overlay mount idmap. Before forwarding the change to the upper layer via ovl_do_notify_change() - whose notify_change() applies the upper layer idmap in turn - rebase ia_vfsuid/ia_vfsgid into the overlay's own id space, i.e. the same space as the overlay inode's i_{u,g}id established by ovl_copyattr(). Without this rebase the upper layer would interpret the caller's mount-relative id as an upper-relative one and store the wrong owner on disk, or reject it with -EOVERFLOW. from_vfsuid() returns INVALID_UID for an id that the overlay mount idmap does not map; that invalid id is carried faithfully into the forwarded iattr and rejected by the upper notify_change() via vfsuid_has_fsmapping(), so no bogus owner can be written. No functional change until FS_ALLOW_IDMAP is set on ovl_fs_type; until then the overlay mount idmap is &nop_mnt_idmap and from_vfsuid() is the identity. Link: https://patch.msgid.link/20260615-work-idmapped-overlayfs-v1-3-7381632aa402@kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29ovl: handle idmapped mounts in ovl_permission()Christian Brauner
When the overlay mount is idmapped, the permission check on the overlay inode must account for the mount's idmapping. Use the struct mnt_idmap passed in by the VFS instead of the hardcoded &nop_mnt_idmap when checking the overlay inode against the caller's credentials. The second check, which verifies that the mounter may access the underlying real inode, continues to use the real layer's idmap mnt_idmap(realpath.mnt) under the mounter's credentials and is deliberately left unchanged. The overlay mount idmap only affects how the caller views the overlay inode, not the mounter's access to the layers, so it cannot widen access to the real files. No functional change until FS_ALLOW_IDMAP is set on ovl_fs_type; until then the overlay mount idmap is always &nop_mnt_idmap. Link: https://patch.msgid.link/20260615-work-idmapped-overlayfs-v1-2-7381632aa402@kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29ovl: handle idmapped mounts in ovl_create_object() and ovl_tmpfile()Christian Brauner
In preparation for allowing the overlay mount itself to be idmapped, thread the mount's struct mnt_idmap into the inode creation path and use it for inode_init_owner() instead of the hardcoded &nop_mnt_idmap. The preallocated overlay inode's i_{u,g}id are copied into the override credentials by ovl_override_creator_creds() to create the real upper inode, so honoring the overlay mount idmap here makes newly created files, directories, special files, symlinks and tmpfiles get the caller's mapped fs{u,g}id once overlay mounts can be idmapped. No functional change: until FS_ALLOW_IDMAP is set on ovl_fs_type the overlay mount idmap is always &nop_mnt_idmap, so inode_init_owner() behaves exactly as before. Link: https://patch.msgid.link/20260615-work-idmapped-overlayfs-v1-1-7381632aa402@kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-05-18ovl: keep err zero after successful ovl_cache_get()Nirmoy Das
ovl_iterate_merged() stores PTR_ERR(cache) in err before checking IS_ERR(cache). On success err holds the truncated cache pointer and can be returned as a bogus non-zero error. The syzbot reproducer reaches this through overlay-on-overlay readdir: getdents64 iterate_dir(outer overlay file) ovl_iterate_merged() ovl_cache_get() ovl_dir_read_merged() ovl_dir_read() iterate_dir(inner overlay file) ovl_iterate_merged() Only compute PTR_ERR(cache) on the error path. Fixes: d25e4b739f83 ("ovl: refactor ovl_iterate() and port to cred guard") Reported-by: syzbot+a16fb0cce329a320661c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=a16fb0cce329a320661c Cc: stable@vger.kernel.org Signed-off-by: Nirmoy Das <nirmoyd@nvidia.com> Link: https://patch.msgid.link/20260514144258.3068715-1-nirmoyd@nvidia.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-05-06ovl: fix verity lazy-load guard broken by fsverity_active() semantic changeColin Walters
Commit f77f281b6118 ("fsverity: use a hashtable to find the fsverity_info") made fsverity_active() check whether the inode has the verity flag, rather than whether the inode's fsverity_info is loaded. This broke ovl_ensure_verity_loaded(), which wants to load the fsverity_info for any verity inodes that haven't had it loaded yet. Therefore, to check that the fsverity_info hasn't yet been loaded, use fsverity_get_info(inode) == NULL instead of !fsverity_active(inode). Also, since fsverity_get_info() now involves a hash table lookup, put the more lightweight IS_VERITY() flag check first. Fixes: f77f281b6118 ("fsverity: use a hashtable to find the fsverity_info") Cc: stable@vger.kernel.org Link: https://github.com/bootc-dev/bootc/issues/2174 Signed-off-by: Colin Walters <walters@verbum.org> Acked-by: Amir Goldstein <amir73il@gmail.com> Link: https://patch.msgid.link/20260505224257.23213-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@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
2026-04-13Merge tag 'lsm-pr-20260410' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm Pull LSM updates from Paul Moore: "We only have five patches in the LSM tree, but three of the five are for an important bugfix relating to overlayfs and the mmap() and mprotect() access controls for LSMs. Highlights below: - Fix problems with the mmap() and mprotect() LSM hooks on overlayfs As we are dealing with problems both in mmap() and mprotect() there are essentially two components to this fix, spread across three patches with all marked for stable. The simplest portion of the fix is the creation of a new LSM hook, security_mmap_backing_file(), that is used to enforce LSM mmap() access controls on backing files in the stacked/overlayfs case. The existing security_mmap_file() does not have visibility past the user file. You can see from the associated SELinux hook callback the code is fairly straightforward. The mprotect() fix is a bit more complicated as there is no way in the mprotect() code path to inspect both the user and backing files, and bolting on a second file reference to vm_area_struct wasn't really an option. The solution taken here adds a LSM security blob and associated hooks to the backing_file struct that LSMs can use to capture and store relevant information from the user file. While the necessary SELinux information is relatively small, a single u32, I expect other LSMs to require more than that, and a dedicated backing_file LSM blob provides a storage mechanism without negatively impacting other filesystems. I want to note that other LSMs beyond SELinux have been involved in the discussion of the fixes presented here and they are working on their own related changes using these new hooks, but due to other issues those patches will be coming at a later date. - Use kstrdup_const()/kfree_const() for securityfs symlink targets - Resolve a handful of kernel-doc warnings in cred.h" * tag 'lsm-pr-20260410' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: selinux: fix overlayfs mmap() and mprotect() access checks lsm: add backing_file LSM hooks fs: prepare for adding LSM blob to backing_file securityfs: use kstrdup_const() to manage symlink targets cred: fix kernel-doc warnings in cred.h
2026-04-13Merge tag 'vfs-7.1-rc1.kino' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs i_ino updates from Christian Brauner: "For historical reasons, the inode->i_ino field is an unsigned long, which means that it's 32 bits on 32 bit architectures. This has caused a number of filesystems to implement hacks to hash a 64-bit identifier into a 32-bit field, and deprives us of a universal identifier field for an inode. This changes the inode->i_ino field from an unsigned long to a u64. This shouldn't make any material difference on 64-bit hosts, but 32-bit hosts will see struct inode grow by at least 4 bytes. This could have effects on slabcache sizes and field alignment. The bulk of the changes are to format strings and tracepoints, since the kernel itself doesn't care that much about the i_ino field. The first patch changes some vfs function arguments, so check that one out carefully. With this change, we may be able to shrink some inode structures. For instance, struct nfs_inode has a fileid field that holds the 64-bit inode number. With this set of changes, that field could be eliminated. I'd rather leave that sort of cleanups for later just to keep this simple" * tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group() EVM: add comment describing why ino field is still unsigned long vfs: remove externs from fs.h on functions modified by i_ino widening treewide: fix missed i_ino format specifier conversions ext4: fix signed format specifier in ext4_load_inode trace event treewide: change inode->i_ino from unsigned long to u64 nilfs2: widen trace event i_ino fields to u64 f2fs: widen trace event i_ino fields to u64 ext4: widen trace event i_ino fields to u64 zonefs: widen trace event i_ino fields to u64 hugetlbfs: widen trace event i_ino fields to u64 ext2: widen trace event i_ino fields to u64 cachefiles: widen trace event i_ino fields to u64 vfs: widen trace event i_ino fields to u64 net: change sock.sk_ino and sock_i_ino() to u64 audit: widen ino fields to u64 vfs: widen inode hash/lookup functions to u64
2026-04-13Merge tag 'vfs-7.1-rc1.directory' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs directory updates from Christian Brauner: "Recently 'start_creating', 'start_removing', 'start_renaming' and related interfaces were added which combine the locking and the lookup. At that time many callers were changed to use the new interfaces. However there are still an assortment of places out side of the core vfs where the directory is locked explictly, whether with inode_lock() or lock_rename() or similar. These were missed in the first pass for an assortment of uninteresting reasons. This addresses the remaining places where explicit locking is used, and changes them to use the new interfaces, or otherwise removes the explicit locking. The biggest changes are in overlayfs. The other changes are quite simple, though maybe the cachefiles changes is the least simple of those" * tag 'vfs-7.1-rc1.directory' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: VFS: unexport lock_rename(), lock_rename_child(), unlock_rename() ovl: remove ovl_lock_rename_workdir() ovl: use is_subdir() for testing if one thing is a subdir of another ovl: change ovl_create_real() to get a new lock when re-opening created file. ovl: pass name buffer to ovl_start_creating_temp() cachefiles: change cachefiles_bury_object to use start_renaming_dentry() ovl: Simplify ovl_lookup_real_one() VFS: make lookup_one_qstr_excl() static. nfsd: switch purge_old() to use start_removing_noperm() selinux: Use simple_start_creating() / simple_done_creating() Apparmor: Use simple_start_creating() / simple_done_creating() libfs: change simple_done_creating() to use end_creating() VFS: move the start_dirop() kerndoc comment to before start_dirop() fs/proc: Don't lock root inode when creating "self" and "thread-self" VFS: note error returns in documentation for various lookup functions
2026-04-03lsm: add backing_file LSM hooksPaul Moore
Stacked filesystems such as overlayfs do not currently provide the necessary mechanisms for LSMs to properly enforce access controls on the mmap() and mprotect() operations. In order to resolve this gap, a LSM security blob is being added to the backing_file struct and the following new LSM hooks are being created: security_backing_file_alloc() security_backing_file_free() security_mmap_backing_file() The first two hooks are to manage the lifecycle of the LSM security blob in the backing_file struct, while the third provides a new mmap() access control point for the underlying backing file. It is also expected that LSMs will likely want to update their security_file_mprotect() callback to address issues with their mprotect() controls, but that does not require a change to the security_file_mprotect() LSM hook. There are a three other small changes to support these new LSM hooks: * Pass the user file associated with a backing file down to alloc_empty_backing_file() so it can be included in the security_backing_file_alloc() hook. * Add getter and setter functions for the backing_file struct LSM blob as the backing_file struct remains private to fs/file_table.c. * Constify the file struct field in the LSM common_audit_data struct to better support LSMs that need to pass a const file struct pointer into the common LSM audit code. Thanks to Arnd Bergmann for identifying the missing EXPORT_SYMBOL_GPL() and supplying a fixup. Cc: stable@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: linux-unionfs@vger.kernel.org Cc: linux-erofs@lists.ozlabs.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
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>
2026-03-27ovl: make fsync after metadata copy-up opt-in mount optionFei Lv
Commit 7d6899fb69d25 ("ovl: fsync after metadata copy-up") was done to fix durability of overlayfs copy up on an upper filesystem which does not enforce ordering on storing of metadata changes (e.g. ubifs). In an earlier revision of the regressing commit by Lei Lv, the metadata fsync behavior was opt-in via a new "fsync=strict" mount option. We were hoping that the opt-in mount option could be avoided, so the change was only made to depend on metacopy=off, in the hope of not hurting performance of metadata heavy workloads, which are more likely to be using metacopy=on. This hope was proven wrong by a performance regression report from Google COS workload after upgrade to kernel 6.12. This is an adaptation of Lei's original "fsync=strict" mount option to the existing upstream code. The new mount option is mutually exclusive with the "volatile" mount option, so the latter is now an alias to the "fsync=volatile" mount option. Reported-by: Chenglong Tang <chenglongtang@google.com> Closes: https://lore.kernel.org/linux-unionfs/CAOdxtTadAFH01Vui1FvWfcmQ8jH1O45owTzUcpYbNvBxnLeM7Q@mail.gmail.com/ Link: https://lore.kernel.org/linux-unionfs/CAOQ4uxgKC1SgjMWre=fUb00v8rxtd6sQi-S+dxR8oDzAuiGu8g@mail.gmail.com/ Fixes: 7d6899fb69d25 ("ovl: fsync after metadata copy-up") Depends: 50e638beb67e0 ("ovl: Use str_on_off() helper in ovl_show_options()") Cc: stable@vger.kernel.org # v6.12+ Signed-off-by: Fei Lv <feilv@asrmicro.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2026-03-24ovl: fix wrong detection of 32bit inode numbersAmir Goldstein
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 <amir73il@gmail.com>
2026-03-09ovl: remove ovl_lock_rename_workdir()NeilBrown
This function is unused since Commit 833d2b3a072f ("Add start_renaming_two_dentries()") Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260224222542.3458677-15-neilb@ownmail.net Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-09ovl: use is_subdir() for testing if one thing is a subdir of anotherNeilBrown
Rather than using lock_rename(), use the more obvious is_subdir() for ensuring that neither upper nor workdir contain the other. Also be explicit in the comment that the two directories cannot be the same. As this is a point-it-time sanity check and does not provide any on-going guarantees, the removal of locking does not introduce any interesting races. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260224222542.3458677-14-neilb@ownmail.net Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-09ovl: change ovl_create_real() to get a new lock when re-opening created file.NeilBrown
When ovl_create_real() is used to create a file on the upper filesystem it needs to return the resulting dentry - positive and hashed. It is usually the case the that dentry passed to the create function (e.g. vfs_create()) will be suitable but this is not guaranteed. The filesystem may unhash that dentry forcing a repeat lookup next time the name is wanted. So ovl_create_real() must be (and is) aware of this and prepared to perform that lookup to get a hash positive dentry. This is currently done under that same directory lock that provided exclusion for the create. Proposed changes to locking will make this not possible - as the name, rather than the directory, will be locked. The new APIs provided for lookup and locking do not and cannot support this pattern. The lock isn't needed. ovl_create_real() can drop the lock and then get a new lock for the lookup - then check that the lookup returned the correct inode. In a well-behaved configuration where the upper filesystem is not being modified by a third party, this will always work reliably, and if there are separate modification it will fail cleanly. So change ovl_create_real() to drop the lock and call ovl_start_creating_upper() to find the correct dentry. Note that start_creating doesn't fail if the name already exists. The lookup previously used the name from newdentry which was guaranteed to be stable because the parent directory was locked. As we now drop the lock we lose that guarantee. As newdentry is unhashed it is unlikely for the name to change, but safest not to depend on that. So the expected name is now passed in to ovl_create_real() and that is used. This removes the only remaining use of ovl_lookup_upper, so it is removed. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260224222542.3458677-13-neilb@ownmail.net Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-09ovl: pass name buffer to ovl_start_creating_temp()NeilBrown
Now ovl_start_creating_temp() is passed a buffer in which to store the temp name. This will be useful in a future patch were ovl_create_real() will need access to that name. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260224222542.3458677-12-neilb@ownmail.net Signed-off-by: Christian Brauner <brauner@kernel.org>
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>
2026-03-06ovl: Simplify ovl_lookup_real_one()NeilBrown
The primary purpose of this patch is to remove the locking from ovl_lookup_real_one() as part of centralising all locking of directories for name operations. The locking here isn't needed. By performing consistency tests after the lookup we can be sure that the result of the lookup was valid at least for a moment, which is all the original code promised. lookup_noperm_unlocked() is used for the lookup and it will take the lock if needed only where it is needed. Also: - don't take a reference to real->d_parent. The parent is only use for a pointer comparison, and no reference is needed for that. - Several "if" statements have a "goto" followed by "else" - the else isn't needed: the following statement can directly follow the "if" as a new statement - Use a consistent pattern of setting "err" before performing a test and possibly going to "fail". - remove the "out" label (now that we don't need to dput(parent) or unlock) and simply return from fail:. Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260224222542.3458677-10-neilb@ownmail.net Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-21Convert 'alloc_flex' family to use the new default GFP_KERNEL argumentLinus Torvalds
This is the exact same thing as the 'alloc_obj()' version, only much smaller because there are a lot fewer users of the *alloc_flex() interface. As with alloc_obj() version, this was done entirely with mindless brute force, using the same script, except using 'flex' in the pattern rather than 'objs*'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.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>
2026-02-17Merge tag 'ovl-update-7.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs Pull overlayfs update from Amir Goldstein: "Relax the semantics of uuid=off to cater to a use case of overlayfs lower layers on btrfs clones, whose UUID are ephemeral and an upper layer on a different filesystem" * tag 'ovl-update-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs: ovl: relax requirement for uuid=off,index=on
2026-02-16Merge tag 'vfs-7.0-rc1.misc.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull more misc vfs updates from Christian Brauner: "Features: - Optimize close_range() from O(range size) to O(active FDs) by using find_next_bit() on the open_fds bitmap instead of linearly scanning the entire requested range. This is a significant improvement for large-range close operations on sparse file descriptor tables. - Add FS_XFLAG_VERITY file attribute for fs-verity files, retrievable via FS_IOC_FSGETXATTR and file_getattr(). The flag is read-only. Add tracepoints for fs-verity enable and verify operations, replacing the previously removed debug printk's. - Prevent nfsd from exporting special kernel filesystems like pidfs and nsfs. These filesystems have custom ->open() and ->permission() export methods that are designed for open_by_handle_at(2) only and are incompatible with nfsd. Update the exportfs documentation accordingly. Fixes: - Fix KMSAN uninit-value in ovl_fill_real() where strcmp() was used on a non-null-terminated decrypted directory entry name from fscrypt. This triggered on encrypted lower layers when the decrypted name buffer contained uninitialized tail data. The fix also adds VFS-level name_is_dot(), name_is_dotdot(), and name_is_dot_dotdot() helpers, replacing various open-coded "." and ".." checks across the tree. - Fix read-only fsflags not being reset together with xflags in vfs_fileattr_set(). Currently harmless since no read-only xflags overlap with flags, but this would cause inconsistencies for any future shared read-only flag - Return -EREMOTE instead of -ESRCH from PIDFD_GET_INFO when the target process is in a different pid namespace. This lets userspace distinguish "process exited" from "process in another namespace", matching glibc's pidfd_getpid() behavior Cleanups: - Use C-string literals in the Rust seq_file bindings, replacing the kernel::c_str!() macro (available since Rust 1.77) - Fix typo in d_walk_ret enum comment, add porting notes for the readlink_copy() calling convention change" * tag 'vfs-7.0-rc1.misc.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: add porting notes about readlink_copy() pidfs: return -EREMOTE when PIDFD_GET_INFO is called on another ns nfsd: do not allow exporting of special kernel filesystems exportfs: clarify the documentation of open()/permission() expotrfs ops fsverity: add tracepoints fs: add FS_XFLAG_VERITY for fs-verity files rust: seq_file: replace `kernel::c_str!` with C-Strings fs: dcache: fix typo in enum d_walk_ret comment ovl: use name_is_dot* helpers in readdir code fs: add helpers name_is_dot{,dot,_dotdot} ovl: Fix uninit-value in ovl_fill_real fs: reset read-only fsflags together with xflags fs/file: optimize close_range() complexity from O(N) to O(Sparse)
2026-02-12Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves disk space by teaching ocfs2 to reclaim suballocator block group space (Heming Zhao) - "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the ARRAY_END() macro and uses it in various places (Alejandro Colomar) - "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the page size (Pnina Feder) - "kallsyms: Prevent invalid access when showing module buildid" cleans up kallsyms code related to module buildid and fixes an invalid access crash when printing backtraces (Petr Mladek) - "Address page fault in ima_restore_measurement_list()" fixes a kexec-related crash that can occur when booting the second-stage kernel on x86 (Harshit Mogalapalli) - "kho: ABI headers and Documentation updates" updates the kexec handover ABI documentation (Mike Rapoport) - "Align atomic storage" adds the __aligned attribute to atomic_t and atomic64_t definitions to get natural alignment of both types on csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain) - "kho: clean up page initialization logic" simplifies the page initialization logic in kho_restore_page() (Pratyush Yadav) - "Unload linux/kernel.h" moves several things out of kernel.h and into more appropriate places (Yury Norov) - "don't abuse task_struct.group_leader" removes the usage of ->group_leader when it is "obviously unnecessary" (Oleg Nesterov) - "list private v2 & luo flb" adds some infrastructure improvements to the live update orchestrator (Pasha Tatashin) * tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits) watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency procfs: fix missing RCU protection when reading real_parent in do_task_stat() watchdog/softlockup: fix sample ring index wrap in need_counting_irqs() kcsan, compiler_types: avoid duplicate type issues in BPF Type Format kho: fix doc for kho_restore_pages() tests/liveupdate: add in-kernel liveupdate test liveupdate: luo_flb: introduce File-Lifecycle-Bound global state liveupdate: luo_file: Use private list list: add kunit test for private list primitives list: add primitives for private list manipulations delayacct: fix uapi timespec64 definition panic: add panic_force_cpu= parameter to redirect panic to a specific CPU netclassid: use thread_group_leader(p) in update_classid_task() RDMA/umem: don't abuse current->group_leader drm/pan*: don't abuse current->group_leader drm/amd: kill the outdated "Only the pthreads threading model is supported" checks drm/amdgpu: don't abuse current->group_leader android/binder: use same_thread_group(proc->tsk, current) in binder_mmap() android/binder: don't abuse current->group_leader kho: skip memoryless NUMA nodes when reserving scratch areas ...
2026-02-09Merge tag 'vfs-7.0-rc1.leases' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs lease updates from Christian Brauner: "This contains updates for lease support to require filesystems to explicitly opt-in to lease support Currently kernel_setlease() falls through to generic_setlease() when a a filesystem does not define ->setlease(), silently granting lease support to every filesystem regardless of whether it is prepared for it. This is a poor default: most filesystems never intended to support leases, and the silent fallthrough makes it impossible to distinguish "supports leases" from "never thought about it". This inverts the default. It adds explicit .setlease = generic_setlease; assignments to every in-tree filesystem that should retain lease support, then changes kernel_setlease() to return -EINVAL when ->setlease is NULL. With the new default in place, simple_nosetlease() is redundant and is removed along with all references to it" * tag 'vfs-7.0-rc1.leases' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (25 commits) fuse: add setlease file operation fs: remove simple_nosetlease() filelock: default to returning -EINVAL when ->setlease operation is NULL xfs: add setlease file operation ufs: add setlease file operation udf: add setlease file operation tmpfs: add setlease file operation squashfs: add setlease file operation overlayfs: add setlease file operation orangefs: add setlease file operation ocfs2: add setlease file operation ntfs3: add setlease file operation nilfs2: add setlease file operation jfs: add setlease file operation jffs2: add setlease file operation gfs2: add a setlease file operation fat: add setlease file operation f2fs: add setlease file operation exfat: add setlease file operation ext4: add setlease file operation ...
2026-02-06ovl: relax requirement for uuid=off,index=onAmir Goldstein
uuid=off,index=on required that all upper/lower directories are on the same filesystem. Relax the requirement so that only all the lower directories need to be on the same filesystem. Reported-by: André Almeida <andrealmeid@igalia.com> Link: https://lore.kernel.org/r/20260114-tonyk-get_disk_uuid-v1-3-e6a319e25d57@igalia.com/ Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2026-01-29ovl: use name_is_dot* helpers in readdir codeAmir Goldstein
Use the helpers in place of all the different open coded variants. This makes the code more readable and robust. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://patch.msgid.link/20260128132406.23768-4-amir73il@gmail.com Reviewed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-29fs: add helpers name_is_dot{,dot,_dotdot}Amir Goldstein
Rename the helper is_dot_dotdot() into the name_ namespace and add complementary helpers to check for dot and dotdot names individually. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://patch.msgid.link/20260128132406.23768-3-amir73il@gmail.com Reviewed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-29ovl: Fix uninit-value in ovl_fill_realQing Wang
Syzbot reported a KMSAN uninit-value issue in ovl_fill_real. This iusse's call chain is: __do_sys_getdents64() -> iterate_dir() ... -> ext4_readdir() -> fscrypt_fname_alloc_buffer() // alloc -> fscrypt_fname_disk_to_usr // write without tail '\0' -> dir_emit() -> ovl_fill_real() // read by strcmp() The string is used to store the decrypted directory entry name for an encrypted inode. As shown in the call chain, fscrypt_fname_disk_to_usr() write it without null-terminate. However, ovl_fill_real() uses strcmp() to compare the name against "..", which assumes a null-terminated string and may trigger a KMSAN uninit-value warning when the buffer tail contains uninit data. Reported-by: syzbot+d130f98b2c265fae5297@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d130f98b2c265fae5297 Fixes: 4edb83bb1041 ("ovl: constant d_ino for non-merge dirs") Signed-off-by: Qing Wang <wangqing7171@gmail.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://patch.msgid.link/20260128132406.23768-2-amir73il@gmail.com Acked-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-20kernel.h: drop hex.h and update all hex.h usersRandy Dunlap
Remove <linux/hex.h> from <linux/kernel.h> and update all users/callers of hex.h interfaces to directly #include <linux/hex.h> as part of the process of putting kernel.h on a diet. Removing hex.h from kernel.h means that 36K C source files don't have to pay the price of parsing hex.h for the roughly 120 C source files that need it. This change has been build-tested with allmodconfig on most ARCHes. Also, all users/callers of <linux/hex.h> in the entire source tree have been updated if needed (if not already #included). Link: https://lkml.kernel.org/r/20251215005206.2362276-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Yury Norov (NVIDIA) <yury.norov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-12fs: add support for non-blocking timestamp updatesChristoph Hellwig
Currently file_update_time_flags unconditionally returns -EAGAIN if any timestamp needs to be updated and IOCB_NOWAIT is passed. This makes non-blocking direct writes impossible on file systems with granular enough timestamps. Pass IOCB_NOWAIT to ->update_time and return -EAGAIN if it could block. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260108141934.2052404-9-hch@lst.de Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-12fs: refactor ->update_time handlingChristoph Hellwig
Pass the type of update (atime vs c/mtime plus version) as an enum instead of a set of flags that caused all kinds of confusion. Because inode_update_timestamps now can't return a modified version of those flags, return the I_DIRTY_* flags needed to persist the update, which is what the main caller in generic_update_time wants anyway, and which is suitable for the other callers that only want to know if an update happened. The whole update_time path keeps the flags argument, which will be used to support non-blocking updates soon even if it is unused, and (the slightly renamed) inode_update_time also gains the possibility to return a negative errno to support this. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260108141934.2052404-6-hch@lst.de Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-12overlayfs: add setlease file operationJeff Layton
Add the setlease file_operation to ovl_file_operations and ovl_dir_operations, pointing to generic_setlease. A future patch will change the default behavior to reject lease attempts with -EINVAL when there is no setlease file operation defined. Add generic_setlease to retain the ability to set leases on this filesystem. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260108-setlease-6-20-v1-17-ea4dec9b67fa@kernel.org Acked-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-12-05ovl: pass original credentials, not mounter credentials during createChristian Brauner
When creating new files the security layer expects the original credentials to be passed. When cleaning up the code this was accidently changed to pass the mounter's credentials by relying on current->cred which is already overriden at this point. Pass the original credentials directly. Reported-by: Ondrej Mosnacek <omosnace@redhat.com> Reported-by: Paul Moore <paul@paul-moore.com> Fixes: e566bff96322 ("ovl: port ovl_create_or_link() to new ovl_override_creator_creds") Link: https://lore.kernel.org/CAFqZXNvL1ciLXMhHrnoyBmQu1PAApH41LkSWEhrcvzAAbFij8Q@mail.gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org> Tested-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-12-05Merge tag 'fuse-update-6.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Add mechanism for cleaning out unused, stale dentries; controlled via a module option (Luis Henriques) - Fix various bugs - Cleanups * tag 'fuse-update-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: Uninitialized variable in fuse_epoch_work() fuse: fix io-uring list corruption for terminated non-committed requests fuse: signal that a fuse inode should exhibit local fs behaviors fuse: Always flush the page cache before FOPEN_DIRECT_IO write fuse: Invalidate the page cache after FOPEN_DIRECT_IO write fuse: rename 'namelen' to 'namesize' fuse: use strscpy instead of strcpy fuse: refactor fuse_conn_put() to remove negative logic. fuse: new work queue to invalidate dentries from old epochs fuse: new work queue to periodically invalidate expired dentries dcache: export shrink_dentry_list() and add new helper d_dispose_if_unused() fuse: add WARN_ON and comment for RCU revalidate fuse: Fix whitespace for fuse_uring_args_to_ring() comment fuse: missing copy_finish in fuse-over-io-uring argument copies fuse: fix readahead reclaim deadlock