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-rw-r--r--fs/overlayfs/util.c1416
1 files changed, 1416 insertions, 0 deletions
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
new file mode 100644
index 000000000..89e0d60d3
--- /dev/null
+++ b/fs/overlayfs/util.c
@@ -0,0 +1,1416 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011 Novell Inc.
+ * Copyright (C) 2016 Red Hat, Inc.
+ */
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/slab.h>
+#include <linux/cred.h>
+#include <linux/xattr.h>
+#include <linux/exportfs.h>
+#include <linux/file.h>
+#include <linux/fileattr.h>
+#include <linux/uuid.h>
+#include <linux/namei.h>
+#include <linux/ratelimit.h>
+#include "overlayfs.h"
+
+int ovl_want_write(struct dentry *dentry)
+{
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
+ return mnt_want_write(ovl_upper_mnt(ofs));
+}
+
+void ovl_drop_write(struct dentry *dentry)
+{
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
+ mnt_drop_write(ovl_upper_mnt(ofs));
+}
+
+struct dentry *ovl_workdir(struct dentry *dentry)
+{
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
+ return ofs->workdir;
+}
+
+const struct cred *ovl_override_creds(struct super_block *sb)
+{
+ struct ovl_fs *ofs = OVL_FS(sb);
+
+ return override_creds(ofs->creator_cred);
+}
+
+/*
+ * Check if underlying fs supports file handles and try to determine encoding
+ * type, in order to deduce maximum inode number used by fs.
+ *
+ * Return 0 if file handles are not supported.
+ * Return 1 (FILEID_INO32_GEN) if fs uses the default 32bit inode encoding.
+ * Return -1 if fs uses a non default encoding with unknown inode size.
+ */
+int ovl_can_decode_fh(struct super_block *sb)
+{
+ if (!capable(CAP_DAC_READ_SEARCH))
+ return 0;
+
+ if (!sb->s_export_op || !sb->s_export_op->fh_to_dentry)
+ return 0;
+
+ return sb->s_export_op->encode_fh ? -1 : FILEID_INO32_GEN;
+}
+
+struct dentry *ovl_indexdir(struct super_block *sb)
+{
+ struct ovl_fs *ofs = OVL_FS(sb);
+
+ return ofs->indexdir;
+}
+
+/* Index all files on copy up. For now only enabled for NFS export */
+bool ovl_index_all(struct super_block *sb)
+{
+ struct ovl_fs *ofs = OVL_FS(sb);
+
+ return ofs->config.nfs_export && ofs->config.index;
+}
+
+/* Verify lower origin on lookup. For now only enabled for NFS export */
+bool ovl_verify_lower(struct super_block *sb)
+{
+ struct ovl_fs *ofs = OVL_FS(sb);
+
+ return ofs->config.nfs_export && ofs->config.index;
+}
+
+struct ovl_path *ovl_stack_alloc(unsigned int n)
+{
+ return kcalloc(n, sizeof(struct ovl_path), GFP_KERNEL);
+}
+
+void ovl_stack_cpy(struct ovl_path *dst, struct ovl_path *src, unsigned int n)
+{
+ unsigned int i;
+
+ memcpy(dst, src, sizeof(struct ovl_path) * n);
+ for (i = 0; i < n; i++)
+ dget(src[i].dentry);
+}
+
+void ovl_stack_put(struct ovl_path *stack, unsigned int n)
+{
+ unsigned int i;
+
+ for (i = 0; stack && i < n; i++)
+ dput(stack[i].dentry);
+}
+
+void ovl_stack_free(struct ovl_path *stack, unsigned int n)
+{
+ ovl_stack_put(stack, n);
+ kfree(stack);
+}
+
+struct ovl_entry *ovl_alloc_entry(unsigned int numlower)
+{
+ size_t size = offsetof(struct ovl_entry, __lowerstack[numlower]);
+ struct ovl_entry *oe = kzalloc(size, GFP_KERNEL);
+
+ if (oe)
+ oe->__numlower = numlower;
+
+ return oe;
+}
+
+void ovl_free_entry(struct ovl_entry *oe)
+{
+ ovl_stack_put(ovl_lowerstack(oe), ovl_numlower(oe));
+ kfree(oe);
+}
+
+#define OVL_D_REVALIDATE (DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE)
+
+bool ovl_dentry_remote(struct dentry *dentry)
+{
+ return dentry->d_flags & OVL_D_REVALIDATE;
+}
+
+void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *realdentry)
+{
+ if (!ovl_dentry_remote(realdentry))
+ return;
+
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags |= realdentry->d_flags & OVL_D_REVALIDATE;
+ spin_unlock(&dentry->d_lock);
+}
+
+void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry,
+ struct ovl_entry *oe)
+{
+ return ovl_dentry_init_flags(dentry, upperdentry, oe, OVL_D_REVALIDATE);
+}
+
+void ovl_dentry_init_flags(struct dentry *dentry, struct dentry *upperdentry,
+ struct ovl_entry *oe, unsigned int mask)
+{
+ struct ovl_path *lowerstack = ovl_lowerstack(oe);
+ unsigned int i, flags = 0;
+
+ if (upperdentry)
+ flags |= upperdentry->d_flags;
+ for (i = 0; i < ovl_numlower(oe) && lowerstack[i].dentry; i++)
+ flags |= lowerstack[i].dentry->d_flags;
+
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags &= ~mask;
+ dentry->d_flags |= flags & mask;
+ spin_unlock(&dentry->d_lock);
+}
+
+bool ovl_dentry_weird(struct dentry *dentry)
+{
+ return dentry->d_flags & (DCACHE_NEED_AUTOMOUNT |
+ DCACHE_MANAGE_TRANSIT |
+ DCACHE_OP_HASH |
+ DCACHE_OP_COMPARE);
+}
+
+enum ovl_path_type ovl_path_type(struct dentry *dentry)
+{
+ struct ovl_entry *oe = OVL_E(dentry);
+ enum ovl_path_type type = 0;
+
+ if (ovl_dentry_upper(dentry)) {
+ type = __OVL_PATH_UPPER;
+
+ /*
+ * Non-dir dentry can hold lower dentry of its copy up origin.
+ */
+ if (ovl_numlower(oe)) {
+ if (ovl_test_flag(OVL_CONST_INO, d_inode(dentry)))
+ type |= __OVL_PATH_ORIGIN;
+ if (d_is_dir(dentry) ||
+ !ovl_has_upperdata(d_inode(dentry)))
+ type |= __OVL_PATH_MERGE;
+ }
+ } else {
+ if (ovl_numlower(oe) > 1)
+ type |= __OVL_PATH_MERGE;
+ }
+ return type;
+}
+
+void ovl_path_upper(struct dentry *dentry, struct path *path)
+{
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
+
+ path->mnt = ovl_upper_mnt(ofs);
+ path->dentry = ovl_dentry_upper(dentry);
+}
+
+void ovl_path_lower(struct dentry *dentry, struct path *path)
+{
+ struct ovl_entry *oe = OVL_E(dentry);
+ struct ovl_path *lowerpath = ovl_lowerstack(oe);
+
+ if (ovl_numlower(oe)) {
+ path->mnt = lowerpath->layer->mnt;
+ path->dentry = lowerpath->dentry;
+ } else {
+ *path = (struct path) { };
+ }
+}
+
+void ovl_path_lowerdata(struct dentry *dentry, struct path *path)
+{
+ struct ovl_entry *oe = OVL_E(dentry);
+ struct ovl_path *lowerdata = ovl_lowerdata(oe);
+ struct dentry *lowerdata_dentry = ovl_lowerdata_dentry(oe);
+
+ if (lowerdata_dentry) {
+ path->dentry = lowerdata_dentry;
+ /*
+ * Pairs with smp_wmb() in ovl_dentry_set_lowerdata().
+ * Make sure that if lowerdata->dentry is visible, then
+ * datapath->layer is visible as well.
+ */
+ smp_rmb();
+ path->mnt = READ_ONCE(lowerdata->layer)->mnt;
+ } else {
+ *path = (struct path) { };
+ }
+}
+
+enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path)
+{
+ enum ovl_path_type type = ovl_path_type(dentry);
+
+ if (!OVL_TYPE_UPPER(type))
+ ovl_path_lower(dentry, path);
+ else
+ ovl_path_upper(dentry, path);
+
+ return type;
+}
+
+enum ovl_path_type ovl_path_realdata(struct dentry *dentry, struct path *path)
+{
+ enum ovl_path_type type = ovl_path_type(dentry);
+
+ WARN_ON_ONCE(d_is_dir(dentry));
+
+ if (!OVL_TYPE_UPPER(type) || OVL_TYPE_MERGE(type))
+ ovl_path_lowerdata(dentry, path);
+ else
+ ovl_path_upper(dentry, path);
+
+ return type;
+}
+
+struct dentry *ovl_dentry_upper(struct dentry *dentry)
+{
+ return ovl_upperdentry_dereference(OVL_I(d_inode(dentry)));
+}
+
+struct dentry *ovl_dentry_lower(struct dentry *dentry)
+{
+ struct ovl_entry *oe = OVL_E(dentry);
+
+ return ovl_numlower(oe) ? ovl_lowerstack(oe)->dentry : NULL;
+}
+
+const struct ovl_layer *ovl_layer_lower(struct dentry *dentry)
+{
+ struct ovl_entry *oe = OVL_E(dentry);
+
+ return ovl_numlower(oe) ? ovl_lowerstack(oe)->layer : NULL;
+}
+
+/*
+ * ovl_dentry_lower() could return either a data dentry or metacopy dentry
+ * depending on what is stored in lowerstack[0]. At times we need to find
+ * lower dentry which has data (and not metacopy dentry). This helper
+ * returns the lower data dentry.
+ */
+struct dentry *ovl_dentry_lowerdata(struct dentry *dentry)
+{
+ return ovl_lowerdata_dentry(OVL_E(dentry));
+}
+
+int ovl_dentry_set_lowerdata(struct dentry *dentry, struct ovl_path *datapath)
+{
+ struct ovl_entry *oe = OVL_E(dentry);
+ struct ovl_path *lowerdata = ovl_lowerdata(oe);
+ struct dentry *datadentry = datapath->dentry;
+
+ if (WARN_ON_ONCE(ovl_numlower(oe) <= 1))
+ return -EIO;
+
+ WRITE_ONCE(lowerdata->layer, datapath->layer);
+ /*
+ * Pairs with smp_rmb() in ovl_path_lowerdata().
+ * Make sure that if lowerdata->dentry is visible, then
+ * lowerdata->layer is visible as well.
+ */
+ smp_wmb();
+ WRITE_ONCE(lowerdata->dentry, dget(datadentry));
+
+ ovl_dentry_update_reval(dentry, datadentry);
+
+ return 0;
+}
+
+struct dentry *ovl_dentry_real(struct dentry *dentry)
+{
+ return ovl_dentry_upper(dentry) ?: ovl_dentry_lower(dentry);
+}
+
+struct dentry *ovl_i_dentry_upper(struct inode *inode)
+{
+ return ovl_upperdentry_dereference(OVL_I(inode));
+}
+
+struct inode *ovl_i_path_real(struct inode *inode, struct path *path)
+{
+ struct ovl_path *lowerpath = ovl_lowerpath(OVL_I_E(inode));
+
+ path->dentry = ovl_i_dentry_upper(inode);
+ if (!path->dentry) {
+ path->dentry = lowerpath->dentry;
+ path->mnt = lowerpath->layer->mnt;
+ } else {
+ path->mnt = ovl_upper_mnt(OVL_FS(inode->i_sb));
+ }
+
+ return path->dentry ? d_inode_rcu(path->dentry) : NULL;
+}
+
+struct inode *ovl_inode_upper(struct inode *inode)
+{
+ struct dentry *upperdentry = ovl_i_dentry_upper(inode);
+
+ return upperdentry ? d_inode(upperdentry) : NULL;
+}
+
+struct inode *ovl_inode_lower(struct inode *inode)
+{
+ struct ovl_path *lowerpath = ovl_lowerpath(OVL_I_E(inode));
+
+ return lowerpath ? d_inode(lowerpath->dentry) : NULL;
+}
+
+struct inode *ovl_inode_real(struct inode *inode)
+{
+ return ovl_inode_upper(inode) ?: ovl_inode_lower(inode);
+}
+
+/* Return inode which contains lower data. Do not return metacopy */
+struct inode *ovl_inode_lowerdata(struct inode *inode)
+{
+ struct dentry *lowerdata = ovl_lowerdata_dentry(OVL_I_E(inode));
+
+ if (WARN_ON(!S_ISREG(inode->i_mode)))
+ return NULL;
+
+ return lowerdata ? d_inode(lowerdata) : NULL;
+}
+
+/* Return real inode which contains data. Does not return metacopy inode */
+struct inode *ovl_inode_realdata(struct inode *inode)
+{
+ struct inode *upperinode;
+
+ upperinode = ovl_inode_upper(inode);
+ if (upperinode && ovl_has_upperdata(inode))
+ return upperinode;
+
+ return ovl_inode_lowerdata(inode);
+}
+
+const char *ovl_lowerdata_redirect(struct inode *inode)
+{
+ return inode && S_ISREG(inode->i_mode) ?
+ OVL_I(inode)->lowerdata_redirect : NULL;
+}
+
+struct ovl_dir_cache *ovl_dir_cache(struct inode *inode)
+{
+ return inode && S_ISDIR(inode->i_mode) ? OVL_I(inode)->cache : NULL;
+}
+
+void ovl_set_dir_cache(struct inode *inode, struct ovl_dir_cache *cache)
+{
+ OVL_I(inode)->cache = cache;
+}
+
+void ovl_dentry_set_flag(unsigned long flag, struct dentry *dentry)
+{
+ set_bit(flag, OVL_E_FLAGS(dentry));
+}
+
+void ovl_dentry_clear_flag(unsigned long flag, struct dentry *dentry)
+{
+ clear_bit(flag, OVL_E_FLAGS(dentry));
+}
+
+bool ovl_dentry_test_flag(unsigned long flag, struct dentry *dentry)
+{
+ return test_bit(flag, OVL_E_FLAGS(dentry));
+}
+
+bool ovl_dentry_is_opaque(struct dentry *dentry)
+{
+ return ovl_dentry_test_flag(OVL_E_OPAQUE, dentry);
+}
+
+bool ovl_dentry_is_whiteout(struct dentry *dentry)
+{
+ return !dentry->d_inode && ovl_dentry_is_opaque(dentry);
+}
+
+void ovl_dentry_set_opaque(struct dentry *dentry)
+{
+ ovl_dentry_set_flag(OVL_E_OPAQUE, dentry);
+}
+
+/*
+ * For hard links and decoded file handles, it's possible for ovl_dentry_upper()
+ * to return positive, while there's no actual upper alias for the inode.
+ * Copy up code needs to know about the existence of the upper alias, so it
+ * can't use ovl_dentry_upper().
+ */
+bool ovl_dentry_has_upper_alias(struct dentry *dentry)
+{
+ return ovl_dentry_test_flag(OVL_E_UPPER_ALIAS, dentry);
+}
+
+void ovl_dentry_set_upper_alias(struct dentry *dentry)
+{
+ ovl_dentry_set_flag(OVL_E_UPPER_ALIAS, dentry);
+}
+
+static bool ovl_should_check_upperdata(struct inode *inode)
+{
+ if (!S_ISREG(inode->i_mode))
+ return false;
+
+ if (!ovl_inode_lower(inode))
+ return false;
+
+ return true;
+}
+
+bool ovl_has_upperdata(struct inode *inode)
+{
+ if (!ovl_should_check_upperdata(inode))
+ return true;
+
+ if (!ovl_test_flag(OVL_UPPERDATA, inode))
+ return false;
+ /*
+ * Pairs with smp_wmb() in ovl_set_upperdata(). Main user of
+ * ovl_has_upperdata() is ovl_copy_up_meta_inode_data(). Make sure
+ * if setting of OVL_UPPERDATA is visible, then effects of writes
+ * before that are visible too.
+ */
+ smp_rmb();
+ return true;
+}
+
+void ovl_set_upperdata(struct inode *inode)
+{
+ /*
+ * Pairs with smp_rmb() in ovl_has_upperdata(). Make sure
+ * if OVL_UPPERDATA flag is visible, then effects of write operations
+ * before it are visible as well.
+ */
+ smp_wmb();
+ ovl_set_flag(OVL_UPPERDATA, inode);
+}
+
+/* Caller should hold ovl_inode->lock */
+bool ovl_dentry_needs_data_copy_up_locked(struct dentry *dentry, int flags)
+{
+ if (!ovl_open_flags_need_copy_up(flags))
+ return false;
+
+ return !ovl_test_flag(OVL_UPPERDATA, d_inode(dentry));
+}
+
+bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags)
+{
+ if (!ovl_open_flags_need_copy_up(flags))
+ return false;
+
+ return !ovl_has_upperdata(d_inode(dentry));
+}
+
+const char *ovl_dentry_get_redirect(struct dentry *dentry)
+{
+ return OVL_I(d_inode(dentry))->redirect;
+}
+
+void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect)
+{
+ struct ovl_inode *oi = OVL_I(d_inode(dentry));
+
+ kfree(oi->redirect);
+ oi->redirect = redirect;
+}
+
+void ovl_inode_update(struct inode *inode, struct dentry *upperdentry)
+{
+ struct inode *upperinode = d_inode(upperdentry);
+
+ WARN_ON(OVL_I(inode)->__upperdentry);
+
+ /*
+ * Make sure upperdentry is consistent before making it visible
+ */
+ smp_wmb();
+ OVL_I(inode)->__upperdentry = upperdentry;
+ if (inode_unhashed(inode)) {
+ inode->i_private = upperinode;
+ __insert_inode_hash(inode, (unsigned long) upperinode);
+ }
+}
+
+static void ovl_dir_version_inc(struct dentry *dentry, bool impurity)
+{
+ struct inode *inode = d_inode(dentry);
+
+ WARN_ON(!inode_is_locked(inode));
+ WARN_ON(!d_is_dir(dentry));
+ /*
+ * Version is used by readdir code to keep cache consistent.
+ * For merge dirs (or dirs with origin) all changes need to be noted.
+ * For non-merge dirs, cache contains only impure entries (i.e. ones
+ * which have been copied up and have origins), so only need to note
+ * changes to impure entries.
+ */
+ if (!ovl_dir_is_real(inode) || impurity)
+ OVL_I(inode)->version++;
+}
+
+void ovl_dir_modified(struct dentry *dentry, bool impurity)
+{
+ /* Copy mtime/ctime */
+ ovl_copyattr(d_inode(dentry));
+
+ ovl_dir_version_inc(dentry, impurity);
+}
+
+u64 ovl_inode_version_get(struct inode *inode)
+{
+ WARN_ON(!inode_is_locked(inode));
+ return OVL_I(inode)->version;
+}
+
+bool ovl_is_whiteout(struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+
+ return inode && IS_WHITEOUT(inode);
+}
+
+struct file *ovl_path_open(const struct path *path, int flags)
+{
+ struct inode *inode = d_inode(path->dentry);
+ struct mnt_idmap *real_idmap = mnt_idmap(path->mnt);
+ int err, acc_mode;
+
+ if (flags & ~(O_ACCMODE | O_LARGEFILE))
+ BUG();
+
+ switch (flags & O_ACCMODE) {
+ case O_RDONLY:
+ acc_mode = MAY_READ;
+ break;
+ case O_WRONLY:
+ acc_mode = MAY_WRITE;
+ break;
+ default:
+ BUG();
+ }
+
+ err = inode_permission(real_idmap, inode, acc_mode | MAY_OPEN);
+ if (err)
+ return ERR_PTR(err);
+
+ /* O_NOATIME is an optimization, don't fail if not permitted */
+ if (inode_owner_or_capable(real_idmap, inode))
+ flags |= O_NOATIME;
+
+ return dentry_open(path, flags, current_cred());
+}
+
+/* Caller should hold ovl_inode->lock */
+static bool ovl_already_copied_up_locked(struct dentry *dentry, int flags)
+{
+ bool disconnected = dentry->d_flags & DCACHE_DISCONNECTED;
+
+ if (ovl_dentry_upper(dentry) &&
+ (ovl_dentry_has_upper_alias(dentry) || disconnected) &&
+ !ovl_dentry_needs_data_copy_up_locked(dentry, flags))
+ return true;
+
+ return false;
+}
+
+bool ovl_already_copied_up(struct dentry *dentry, int flags)
+{
+ bool disconnected = dentry->d_flags & DCACHE_DISCONNECTED;
+
+ /*
+ * Check if copy-up has happened as well as for upper alias (in
+ * case of hard links) is there.
+ *
+ * Both checks are lockless:
+ * - false negatives: will recheck under oi->lock
+ * - false positives:
+ * + ovl_dentry_upper() uses memory barriers to ensure the
+ * upper dentry is up-to-date
+ * + ovl_dentry_has_upper_alias() relies on locking of
+ * upper parent i_rwsem to prevent reordering copy-up
+ * with rename.
+ */
+ if (ovl_dentry_upper(dentry) &&
+ (ovl_dentry_has_upper_alias(dentry) || disconnected) &&
+ !ovl_dentry_needs_data_copy_up(dentry, flags))
+ return true;
+
+ return false;
+}
+
+int ovl_copy_up_start(struct dentry *dentry, int flags)
+{
+ struct inode *inode = d_inode(dentry);
+ int err;
+
+ err = ovl_inode_lock_interruptible(inode);
+ if (!err && ovl_already_copied_up_locked(dentry, flags)) {
+ err = 1; /* Already copied up */
+ ovl_inode_unlock(inode);
+ }
+
+ return err;
+}
+
+void ovl_copy_up_end(struct dentry *dentry)
+{
+ ovl_inode_unlock(d_inode(dentry));
+}
+
+bool ovl_path_check_origin_xattr(struct ovl_fs *ofs, const struct path *path)
+{
+ int res;
+
+ res = ovl_path_getxattr(ofs, path, OVL_XATTR_ORIGIN, NULL, 0);
+
+ /* Zero size value means "copied up but origin unknown" */
+ if (res >= 0)
+ return true;
+
+ return false;
+}
+
+/*
+ * Load persistent uuid from xattr into s_uuid if found, or store a new
+ * random generated value in s_uuid and in xattr.
+ */
+bool ovl_init_uuid_xattr(struct super_block *sb, struct ovl_fs *ofs,
+ const struct path *upperpath)
+{
+ bool set = false;
+ int res;
+
+ /* Try to load existing persistent uuid */
+ res = ovl_path_getxattr(ofs, upperpath, OVL_XATTR_UUID, sb->s_uuid.b,
+ UUID_SIZE);
+ if (res == UUID_SIZE)
+ return true;
+
+ if (res != -ENODATA)
+ goto fail;
+
+ /*
+ * With uuid=auto, if uuid xattr is found, it will be used.
+ * If uuid xattrs is not found, generate a persistent uuid only on mount
+ * of new overlays where upper root dir is not yet marked as impure.
+ * An upper dir is marked as impure on copy up or lookup of its subdirs.
+ */
+ if (ofs->config.uuid == OVL_UUID_AUTO) {
+ res = ovl_path_getxattr(ofs, upperpath, OVL_XATTR_IMPURE, NULL,
+ 0);
+ if (res > 0) {
+ /* Any mount of old overlay - downgrade to uuid=null */
+ ofs->config.uuid = OVL_UUID_NULL;
+ return true;
+ } else if (res == -ENODATA) {
+ /* First mount of new overlay - upgrade to uuid=on */
+ ofs->config.uuid = OVL_UUID_ON;
+ } else if (res < 0) {
+ goto fail;
+ }
+
+ }
+
+ /* Generate overlay instance uuid */
+ uuid_gen(&sb->s_uuid);
+
+ /* Try to store persistent uuid */
+ set = true;
+ res = ovl_setxattr(ofs, upperpath->dentry, OVL_XATTR_UUID, sb->s_uuid.b,
+ UUID_SIZE);
+ if (res == 0)
+ return true;
+
+fail:
+ memset(sb->s_uuid.b, 0, UUID_SIZE);
+ ofs->config.uuid = OVL_UUID_NULL;
+ pr_warn("failed to %s uuid (%pd2, err=%i); falling back to uuid=null.\n",
+ set ? "set" : "get", upperpath->dentry, res);
+ return false;
+}
+
+bool ovl_path_check_dir_xattr(struct ovl_fs *ofs, const struct path *path,
+ enum ovl_xattr ox)
+{
+ int res;
+ char val;
+
+ if (!d_is_dir(path->dentry))
+ return false;
+
+ res = ovl_path_getxattr(ofs, path, ox, &val, 1);
+ if (res == 1 && val == 'y')
+ return true;
+
+ return false;
+}
+
+#define OVL_XATTR_OPAQUE_POSTFIX "opaque"
+#define OVL_XATTR_REDIRECT_POSTFIX "redirect"
+#define OVL_XATTR_ORIGIN_POSTFIX "origin"
+#define OVL_XATTR_IMPURE_POSTFIX "impure"
+#define OVL_XATTR_NLINK_POSTFIX "nlink"
+#define OVL_XATTR_UPPER_POSTFIX "upper"
+#define OVL_XATTR_UUID_POSTFIX "uuid"
+#define OVL_XATTR_METACOPY_POSTFIX "metacopy"
+#define OVL_XATTR_PROTATTR_POSTFIX "protattr"
+
+#define OVL_XATTR_TAB_ENTRY(x) \
+ [x] = { [false] = OVL_XATTR_TRUSTED_PREFIX x ## _POSTFIX, \
+ [true] = OVL_XATTR_USER_PREFIX x ## _POSTFIX }
+
+const char *const ovl_xattr_table[][2] = {
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_OPAQUE),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_REDIRECT),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_ORIGIN),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_IMPURE),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_NLINK),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_UPPER),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_UUID),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_METACOPY),
+ OVL_XATTR_TAB_ENTRY(OVL_XATTR_PROTATTR),
+};
+
+int ovl_check_setxattr(struct ovl_fs *ofs, struct dentry *upperdentry,
+ enum ovl_xattr ox, const void *value, size_t size,
+ int xerr)
+{
+ int err;
+
+ if (ofs->noxattr)
+ return xerr;
+
+ err = ovl_setxattr(ofs, upperdentry, ox, value, size);
+
+ if (err == -EOPNOTSUPP) {
+ pr_warn("cannot set %s xattr on upper\n", ovl_xattr(ofs, ox));
+ ofs->noxattr = true;
+ return xerr;
+ }
+
+ return err;
+}
+
+int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry)
+{
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
+ int err;
+
+ if (ovl_test_flag(OVL_IMPURE, d_inode(dentry)))
+ return 0;
+
+ /*
+ * Do not fail when upper doesn't support xattrs.
+ * Upper inodes won't have origin nor redirect xattr anyway.
+ */
+ err = ovl_check_setxattr(ofs, upperdentry, OVL_XATTR_IMPURE, "y", 1, 0);
+ if (!err)
+ ovl_set_flag(OVL_IMPURE, d_inode(dentry));
+
+ return err;
+}
+
+
+#define OVL_PROTATTR_MAX 32 /* Reserved for future flags */
+
+void ovl_check_protattr(struct inode *inode, struct dentry *upper)
+{
+ struct ovl_fs *ofs = OVL_FS(inode->i_sb);
+ u32 iflags = inode->i_flags & OVL_PROT_I_FLAGS_MASK;
+ char buf[OVL_PROTATTR_MAX+1];
+ int res, n;
+
+ res = ovl_getxattr_upper(ofs, upper, OVL_XATTR_PROTATTR, buf,
+ OVL_PROTATTR_MAX);
+ if (res < 0)
+ return;
+
+ /*
+ * Initialize inode flags from overlay.protattr xattr and upper inode
+ * flags. If upper inode has those fileattr flags set (i.e. from old
+ * kernel), we do not clear them on ovl_get_inode(), but we will clear
+ * them on next fileattr_set().
+ */
+ for (n = 0; n < res; n++) {
+ if (buf[n] == 'a')
+ iflags |= S_APPEND;
+ else if (buf[n] == 'i')
+ iflags |= S_IMMUTABLE;
+ else
+ break;
+ }
+
+ if (!res || n < res) {
+ pr_warn_ratelimited("incompatible overlay.protattr format (%pd2, len=%d)\n",
+ upper, res);
+ } else {
+ inode_set_flags(inode, iflags, OVL_PROT_I_FLAGS_MASK);
+ }
+}
+
+int ovl_set_protattr(struct inode *inode, struct dentry *upper,
+ struct fileattr *fa)
+{
+ struct ovl_fs *ofs = OVL_FS(inode->i_sb);
+ char buf[OVL_PROTATTR_MAX];
+ int len = 0, err = 0;
+ u32 iflags = 0;
+
+ BUILD_BUG_ON(HWEIGHT32(OVL_PROT_FS_FLAGS_MASK) > OVL_PROTATTR_MAX);
+
+ if (fa->flags & FS_APPEND_FL) {
+ buf[len++] = 'a';
+ iflags |= S_APPEND;
+ }
+ if (fa->flags & FS_IMMUTABLE_FL) {
+ buf[len++] = 'i';
+ iflags |= S_IMMUTABLE;
+ }
+
+ /*
+ * Do not allow to set protection flags when upper doesn't support
+ * xattrs, because we do not set those fileattr flags on upper inode.
+ * Remove xattr if it exist and all protection flags are cleared.
+ */
+ if (len) {
+ err = ovl_check_setxattr(ofs, upper, OVL_XATTR_PROTATTR,
+ buf, len, -EPERM);
+ } else if (inode->i_flags & OVL_PROT_I_FLAGS_MASK) {
+ err = ovl_removexattr(ofs, upper, OVL_XATTR_PROTATTR);
+ if (err == -EOPNOTSUPP || err == -ENODATA)
+ err = 0;
+ }
+ if (err)
+ return err;
+
+ inode_set_flags(inode, iflags, OVL_PROT_I_FLAGS_MASK);
+
+ /* Mask out the fileattr flags that should not be set in upper inode */
+ fa->flags &= ~OVL_PROT_FS_FLAGS_MASK;
+ fa->fsx_xflags &= ~OVL_PROT_FSX_FLAGS_MASK;
+
+ return 0;
+}
+
+/**
+ * Caller must hold a reference to inode to prevent it from being freed while
+ * it is marked inuse.
+ */
+bool ovl_inuse_trylock(struct dentry *dentry)
+{
+ struct inode *inode = d_inode(dentry);
+ bool locked = false;
+
+ spin_lock(&inode->i_lock);
+ if (!(inode->i_state & I_OVL_INUSE)) {
+ inode->i_state |= I_OVL_INUSE;
+ locked = true;
+ }
+ spin_unlock(&inode->i_lock);
+
+ return locked;
+}
+
+void ovl_inuse_unlock(struct dentry *dentry)
+{
+ if (dentry) {
+ struct inode *inode = d_inode(dentry);
+
+ spin_lock(&inode->i_lock);
+ WARN_ON(!(inode->i_state & I_OVL_INUSE));
+ inode->i_state &= ~I_OVL_INUSE;
+ spin_unlock(&inode->i_lock);
+ }
+}
+
+bool ovl_is_inuse(struct dentry *dentry)
+{
+ struct inode *inode = d_inode(dentry);
+ bool inuse;
+
+ spin_lock(&inode->i_lock);
+ inuse = (inode->i_state & I_OVL_INUSE);
+ spin_unlock(&inode->i_lock);
+
+ return inuse;
+}
+
+/*
+ * Does this overlay dentry need to be indexed on copy up?
+ */
+bool ovl_need_index(struct dentry *dentry)
+{
+ struct dentry *lower = ovl_dentry_lower(dentry);
+
+ if (!lower || !ovl_indexdir(dentry->d_sb))
+ return false;
+
+ /* Index all files for NFS export and consistency verification */
+ if (ovl_index_all(dentry->d_sb))
+ return true;
+
+ /* Index only lower hardlinks on copy up */
+ if (!d_is_dir(lower) && d_inode(lower)->i_nlink > 1)
+ return true;
+
+ return false;
+}
+
+/* Caller must hold OVL_I(inode)->lock */
+static void ovl_cleanup_index(struct dentry *dentry)
+{
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
+ struct dentry *indexdir = ovl_indexdir(dentry->d_sb);
+ struct inode *dir = indexdir->d_inode;
+ struct dentry *lowerdentry = ovl_dentry_lower(dentry);
+ struct dentry *upperdentry = ovl_dentry_upper(dentry);
+ struct dentry *index = NULL;
+ struct inode *inode;
+ struct qstr name = { };
+ int err;
+
+ err = ovl_get_index_name(ofs, lowerdentry, &name);
+ if (err)
+ goto fail;
+
+ inode = d_inode(upperdentry);
+ if (!S_ISDIR(inode->i_mode) && inode->i_nlink != 1) {
+ pr_warn_ratelimited("cleanup linked index (%pd2, ino=%lu, nlink=%u)\n",
+ upperdentry, inode->i_ino, inode->i_nlink);
+ /*
+ * We either have a bug with persistent union nlink or a lower
+ * hardlink was added while overlay is mounted. Adding a lower
+ * hardlink and then unlinking all overlay hardlinks would drop
+ * overlay nlink to zero before all upper inodes are unlinked.
+ * As a safety measure, when that situation is detected, set
+ * the overlay nlink to the index inode nlink minus one for the
+ * index entry itself.
+ */
+ set_nlink(d_inode(dentry), inode->i_nlink - 1);
+ ovl_set_nlink_upper(dentry);
+ goto out;
+ }
+
+ inode_lock_nested(dir, I_MUTEX_PARENT);
+ index = ovl_lookup_upper(ofs, name.name, indexdir, name.len);
+ err = PTR_ERR(index);
+ if (IS_ERR(index)) {
+ index = NULL;
+ } else if (ovl_index_all(dentry->d_sb)) {
+ /* Whiteout orphan index to block future open by handle */
+ err = ovl_cleanup_and_whiteout(OVL_FS(dentry->d_sb),
+ dir, index);
+ } else {
+ /* Cleanup orphan index entries */
+ err = ovl_cleanup(ofs, dir, index);
+ }
+
+ inode_unlock(dir);
+ if (err)
+ goto fail;
+
+out:
+ kfree(name.name);
+ dput(index);
+ return;
+
+fail:
+ pr_err("cleanup index of '%pd2' failed (%i)\n", dentry, err);
+ goto out;
+}
+
+/*
+ * Operations that change overlay inode and upper inode nlink need to be
+ * synchronized with copy up for persistent nlink accounting.
+ */
+int ovl_nlink_start(struct dentry *dentry)
+{
+ struct inode *inode = d_inode(dentry);
+ const struct cred *old_cred;
+ int err;
+
+ if (WARN_ON(!inode))
+ return -ENOENT;
+
+ /*
+ * With inodes index is enabled, we store the union overlay nlink
+ * in an xattr on the index inode. When whiting out an indexed lower,
+ * we need to decrement the overlay persistent nlink, but before the
+ * first copy up, we have no upper index inode to store the xattr.
+ *
+ * As a workaround, before whiteout/rename over an indexed lower,
+ * copy up to create the upper index. Creating the upper index will
+ * initialize the overlay nlink, so it could be dropped if unlink
+ * or rename succeeds.
+ *
+ * TODO: implement metadata only index copy up when called with
+ * ovl_copy_up_flags(dentry, O_PATH).
+ */
+ if (ovl_need_index(dentry) && !ovl_dentry_has_upper_alias(dentry)) {
+ err = ovl_copy_up(dentry);
+ if (err)
+ return err;
+ }
+
+ err = ovl_inode_lock_interruptible(inode);
+ if (err)
+ return err;
+
+ if (d_is_dir(dentry) || !ovl_test_flag(OVL_INDEX, inode))
+ goto out;
+
+ old_cred = ovl_override_creds(dentry->d_sb);
+ /*
+ * The overlay inode nlink should be incremented/decremented IFF the
+ * upper operation succeeds, along with nlink change of upper inode.
+ * Therefore, before link/unlink/rename, we store the union nlink
+ * value relative to the upper inode nlink in an upper inode xattr.
+ */
+ err = ovl_set_nlink_upper(dentry);
+ revert_creds(old_cred);
+
+out:
+ if (err)
+ ovl_inode_unlock(inode);
+
+ return err;
+}
+
+void ovl_nlink_end(struct dentry *dentry)
+{
+ struct inode *inode = d_inode(dentry);
+
+ if (ovl_test_flag(OVL_INDEX, inode) && inode->i_nlink == 0) {
+ const struct cred *old_cred;
+
+ old_cred = ovl_override_creds(dentry->d_sb);
+ ovl_cleanup_index(dentry);
+ revert_creds(old_cred);
+ }
+
+ ovl_inode_unlock(inode);
+}
+
+int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)
+{
+ /* Workdir should not be the same as upperdir */
+ if (workdir == upperdir)
+ goto err;
+
+ /* Workdir should not be subdir of upperdir and vice versa */
+ if (lock_rename(workdir, upperdir) != NULL)
+ goto err_unlock;
+
+ return 0;
+
+err_unlock:
+ unlock_rename(workdir, upperdir);
+err:
+ pr_err("failed to lock workdir+upperdir\n");
+ return -EIO;
+}
+
+/*
+ * err < 0, 0 if no metacopy xattr, metacopy data size if xattr found.
+ * an empty xattr returns OVL_METACOPY_MIN_SIZE to distinguish from no xattr value.
+ */
+int ovl_check_metacopy_xattr(struct ovl_fs *ofs, const struct path *path,
+ struct ovl_metacopy *data)
+{
+ int res;
+
+ /* Only regular files can have metacopy xattr */
+ if (!S_ISREG(d_inode(path->dentry)->i_mode))
+ return 0;
+
+ res = ovl_path_getxattr(ofs, path, OVL_XATTR_METACOPY,
+ data, data ? OVL_METACOPY_MAX_SIZE : 0);
+ if (res < 0) {
+ if (res == -ENODATA || res == -EOPNOTSUPP)
+ return 0;
+ /*
+ * getxattr on user.* may fail with EACCES in case there's no
+ * read permission on the inode. Not much we can do, other than
+ * tell the caller that this is not a metacopy inode.
+ */
+ if (ofs->config.userxattr && res == -EACCES)
+ return 0;
+ goto out;
+ }
+
+ if (res == 0) {
+ /* Emulate empty data for zero size metacopy xattr */
+ res = OVL_METACOPY_MIN_SIZE;
+ if (data) {
+ memset(data, 0, res);
+ data->len = res;
+ }
+ } else if (res < OVL_METACOPY_MIN_SIZE) {
+ pr_warn_ratelimited("metacopy file '%pd' has too small xattr\n",
+ path->dentry);
+ return -EIO;
+ } else if (data) {
+ if (data->version != 0) {
+ pr_warn_ratelimited("metacopy file '%pd' has unsupported version\n",
+ path->dentry);
+ return -EIO;
+ }
+ if (res != data->len) {
+ pr_warn_ratelimited("metacopy file '%pd' has invalid xattr size\n",
+ path->dentry);
+ return -EIO;
+ }
+ }
+
+ return res;
+out:
+ pr_warn_ratelimited("failed to get metacopy (%i)\n", res);
+ return res;
+}
+
+int ovl_set_metacopy_xattr(struct ovl_fs *ofs, struct dentry *d, struct ovl_metacopy *metacopy)
+{
+ size_t len = metacopy->len;
+
+ /* If no flags or digest fall back to empty metacopy file */
+ if (metacopy->version == 0 && metacopy->flags == 0 && metacopy->digest_algo == 0)
+ len = 0;
+
+ return ovl_check_setxattr(ofs, d, OVL_XATTR_METACOPY,
+ metacopy, len, -EOPNOTSUPP);
+}
+
+bool ovl_is_metacopy_dentry(struct dentry *dentry)
+{
+ struct ovl_entry *oe = OVL_E(dentry);
+
+ if (!d_is_reg(dentry))
+ return false;
+
+ if (ovl_dentry_upper(dentry)) {
+ if (!ovl_has_upperdata(d_inode(dentry)))
+ return true;
+ return false;
+ }
+
+ return (ovl_numlower(oe) > 1);
+}
+
+char *ovl_get_redirect_xattr(struct ovl_fs *ofs, const struct path *path, int padding)
+{
+ int res;
+ char *s, *next, *buf = NULL;
+
+ res = ovl_path_getxattr(ofs, path, OVL_XATTR_REDIRECT, NULL, 0);
+ if (res == -ENODATA || res == -EOPNOTSUPP)
+ return NULL;
+ if (res < 0)
+ goto fail;
+ if (res == 0)
+ goto invalid;
+
+ buf = kzalloc(res + padding + 1, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+
+ res = ovl_path_getxattr(ofs, path, OVL_XATTR_REDIRECT, buf, res);
+ if (res < 0)
+ goto fail;
+ if (res == 0)
+ goto invalid;
+
+ if (buf[0] == '/') {
+ for (s = buf; *s++ == '/'; s = next) {
+ next = strchrnul(s, '/');
+ if (s == next)
+ goto invalid;
+ }
+ } else {
+ if (strchr(buf, '/') != NULL)
+ goto invalid;
+ }
+
+ return buf;
+invalid:
+ pr_warn_ratelimited("invalid redirect (%s)\n", buf);
+ res = -EINVAL;
+ goto err_free;
+fail:
+ pr_warn_ratelimited("failed to get redirect (%i)\n", res);
+err_free:
+ kfree(buf);
+ return ERR_PTR(res);
+}
+
+/* Call with mounter creds as it may open the file */
+int ovl_ensure_verity_loaded(struct path *datapath)
+{
+ struct inode *inode = d_inode(datapath->dentry);
+ struct file *filp;
+
+ if (!fsverity_active(inode) && IS_VERITY(inode)) {
+ /*
+ * If this inode was not yet opened, the verity info hasn't been
+ * loaded yet, so we need to do that here to force it into memory.
+ */
+ filp = kernel_file_open(datapath, O_RDONLY, inode, current_cred());
+ if (IS_ERR(filp))
+ return PTR_ERR(filp);
+ fput(filp);
+ }
+
+ return 0;
+}
+
+int ovl_validate_verity(struct ovl_fs *ofs,
+ struct path *metapath,
+ struct path *datapath)
+{
+ struct ovl_metacopy metacopy_data;
+ u8 actual_digest[FS_VERITY_MAX_DIGEST_SIZE];
+ int xattr_digest_size, digest_size;
+ int xattr_size, err;
+ u8 verity_algo;
+
+ if (!ofs->config.verity_mode ||
+ /* Verity only works on regular files */
+ !S_ISREG(d_inode(metapath->dentry)->i_mode))
+ return 0;
+
+ xattr_size = ovl_check_metacopy_xattr(ofs, metapath, &metacopy_data);
+ if (xattr_size < 0)
+ return xattr_size;
+
+ if (!xattr_size || !metacopy_data.digest_algo) {
+ if (ofs->config.verity_mode == OVL_VERITY_REQUIRE) {
+ pr_warn_ratelimited("metacopy file '%pd' has no digest specified\n",
+ metapath->dentry);
+ return -EIO;
+ }
+ return 0;
+ }
+
+ xattr_digest_size = ovl_metadata_digest_size(&metacopy_data);
+
+ err = ovl_ensure_verity_loaded(datapath);
+ if (err < 0) {
+ pr_warn_ratelimited("lower file '%pd' failed to load fs-verity info\n",
+ datapath->dentry);
+ return -EIO;
+ }
+
+ digest_size = fsverity_get_digest(d_inode(datapath->dentry), actual_digest,
+ &verity_algo, NULL);
+ if (digest_size == 0) {
+ pr_warn_ratelimited("lower file '%pd' has no fs-verity digest\n", datapath->dentry);
+ return -EIO;
+ }
+
+ if (xattr_digest_size != digest_size ||
+ metacopy_data.digest_algo != verity_algo ||
+ memcmp(metacopy_data.digest, actual_digest, xattr_digest_size) != 0) {
+ pr_warn_ratelimited("lower file '%pd' has the wrong fs-verity digest\n",
+ datapath->dentry);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+int ovl_get_verity_digest(struct ovl_fs *ofs, struct path *src,
+ struct ovl_metacopy *metacopy)
+{
+ int err, digest_size;
+
+ if (!ofs->config.verity_mode || !S_ISREG(d_inode(src->dentry)->i_mode))
+ return 0;
+
+ err = ovl_ensure_verity_loaded(src);
+ if (err < 0) {
+ pr_warn_ratelimited("lower file '%pd' failed to load fs-verity info\n",
+ src->dentry);
+ return -EIO;
+ }
+
+ digest_size = fsverity_get_digest(d_inode(src->dentry),
+ metacopy->digest, &metacopy->digest_algo, NULL);
+ if (digest_size == 0 ||
+ WARN_ON_ONCE(digest_size > FS_VERITY_MAX_DIGEST_SIZE)) {
+ if (ofs->config.verity_mode == OVL_VERITY_REQUIRE) {
+ pr_warn_ratelimited("lower file '%pd' has no fs-verity digest\n",
+ src->dentry);
+ return -EIO;
+ }
+ return 0;
+ }
+
+ metacopy->len += digest_size;
+ return 0;
+}
+
+/*
+ * ovl_sync_status() - Check fs sync status for volatile mounts
+ *
+ * Returns 1 if this is not a volatile mount and a real sync is required.
+ *
+ * Returns 0 if syncing can be skipped because mount is volatile, and no errors
+ * have occurred on the upperdir since the mount.
+ *
+ * Returns -errno if it is a volatile mount, and the error that occurred since
+ * the last mount. If the error code changes, it'll return the latest error
+ * code.
+ */
+
+int ovl_sync_status(struct ovl_fs *ofs)
+{
+ struct vfsmount *mnt;
+
+ if (ovl_should_sync(ofs))
+ return 1;
+
+ mnt = ovl_upper_mnt(ofs);
+ if (!mnt)
+ return 0;
+
+ return errseq_check(&mnt->mnt_sb->s_wb_err, ofs->errseq);
+}
+
+/*
+ * ovl_copyattr() - copy inode attributes from layer to ovl inode
+ *
+ * When overlay copies inode information from an upper or lower layer to the
+ * relevant overlay inode it will apply the idmapping of the upper or lower
+ * layer when doing so ensuring that the ovl inode ownership will correctly
+ * reflect the ownership of the idmapped upper or lower layer. For example, an
+ * idmapped upper or lower layer mapping id 1001 to id 1000 will take care to
+ * map any lower or upper inode owned by id 1001 to id 1000. These mapping
+ * helpers are nops when the relevant layer isn't idmapped.
+ */
+void ovl_copyattr(struct inode *inode)
+{
+ struct path realpath;
+ struct inode *realinode;
+ struct mnt_idmap *real_idmap;
+ vfsuid_t vfsuid;
+ vfsgid_t vfsgid;
+
+ realinode = ovl_i_path_real(inode, &realpath);
+ real_idmap = mnt_idmap(realpath.mnt);
+
+ vfsuid = i_uid_into_vfsuid(real_idmap, realinode);
+ vfsgid = i_gid_into_vfsgid(real_idmap, realinode);
+
+ inode->i_uid = vfsuid_into_kuid(vfsuid);
+ inode->i_gid = vfsgid_into_kgid(vfsgid);
+ inode->i_mode = realinode->i_mode;
+ inode->i_atime = realinode->i_atime;
+ inode->i_mtime = realinode->i_mtime;
+ inode_set_ctime_to_ts(inode, inode_get_ctime(realinode));
+ i_size_write(inode, i_size_read(realinode));
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-20 19:23:14 +0000