torvalds/linux
3
0
Fork 0
mirror of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-03-22 07:27:12 +08:00
Code Issues Packages Projects Releases Wiki Activity

ovl: introduce struct ovl_renamedata

Browse Source 
Add a struct ovl_renamedata to group rename-related state that was
previously stored in local variables. Embedd struct renamedata directly
aligning with the vfs.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://patch.msgid.link/20251117-work-ovl-cred-guard-v4-33-b31603935724@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Christian Brauner
2025-11-19 18:50:56 +01:00
parent 0b5800172c
commit fb9f31fe9f
1 changed files with 45 additions and 33 deletions
Download Patch File Download Diff File Expand all files Collapse all files

78
fs/overlayfs/dir.c
View File

@@ -1094,6 +1094,14 @@ static int ovl_set_redirect(struct dentry *dentry, bool samedir)
return err;
}
struct ovl_renamedata {
struct renamedata;
struct dentry *opaquedir;
bool cleanup_whiteout;
bool update_nlink;
bool overwrite;
};
static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
struct dentry *old, struct inode *newdir,
struct dentry *new, unsigned int flags)
@@ -1104,49 +1112,53 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
struct renamedata rd = {};
bool old_opaque;
bool new_opaque;
bool cleanup_whiteout = false;
bool update_nlink = false;
bool overwrite = !(flags & RENAME_EXCHANGE);
bool is_dir = d_is_dir(old);
bool new_is_dir = d_is_dir(new);
bool samedir = olddir == newdir;
struct dentry *opaquedir = NULL;
bool samedir = old->d_parent == new->d_parent;
struct dentry *whiteout = NULL;
const struct cred *old_cred = NULL;
struct ovl_fs *ofs = OVL_FS(old->d_sb);
struct ovl_renamedata _ovlrd = {
.old_dentry = old,
.new_dentry = new,
.flags = flags,
.cleanup_whiteout = false,
.overwrite = !(flags & RENAME_EXCHANGE),
};
struct ovl_renamedata *ovlrd = &_ovlrd;
LIST_HEAD(list);
err = -EINVAL;
if (flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE))
if (ovlrd->flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE))
goto out;
flags &= ~RENAME_NOREPLACE;
ovlrd->flags &= ~RENAME_NOREPLACE;
/* Don't copy up directory trees */
err = -EXDEV;
if (!ovl_can_move(old))
goto out;
if (!overwrite && !ovl_can_move(new))
if (!ovlrd->overwrite && !ovl_can_move(new))
goto out;
if (overwrite && new_is_dir && !ovl_pure_upper(new)) {
if (ovlrd->overwrite && new_is_dir && !ovl_pure_upper(new)) {
err = ovl_check_empty_dir(new, &list);
if (err)
goto out;
}
if (overwrite) {
if (ovlrd->overwrite) {
if (ovl_lower_positive(old)) {
if (!ovl_dentry_is_whiteout(new)) {
/* Whiteout source */
flags |= RENAME_WHITEOUT;
ovlrd->flags |= RENAME_WHITEOUT;
} else {
/* Switch whiteouts */
flags |= RENAME_EXCHANGE;
ovlrd->flags |= RENAME_EXCHANGE;
}
} else if (is_dir && ovl_dentry_is_whiteout(new)) {
flags |= RENAME_EXCHANGE;
cleanup_whiteout = true;
ovlrd->flags |= RENAME_EXCHANGE;
ovlrd->cleanup_whiteout = true;
}
}
@@ -1157,7 +1169,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
err = ovl_copy_up(new->d_parent);
if (err)
goto out;
if (!overwrite) {
if (!ovlrd->overwrite) {
err = ovl_copy_up(new);
if (err)
goto out;
@@ -1166,10 +1178,10 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
if (err)
goto out;
update_nlink = true;
ovlrd->update_nlink = true;
}
if (!update_nlink) {
if (!ovlrd->update_nlink) {
/* ovl_nlink_start() took ovl_want_write() */
err = ovl_want_write(old);
if (err)
@@ -1179,10 +1191,10 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
old_cred = ovl_override_creds(old->d_sb);
if (!list_empty(&list)) {
opaquedir = ovl_clear_empty(new, &list);
err = PTR_ERR(opaquedir);
if (IS_ERR(opaquedir)) {
opaquedir = NULL;
ovlrd->opaquedir = ovl_clear_empty(new, &list);
err = PTR_ERR(ovlrd->opaquedir);
if (IS_ERR(ovlrd->opaquedir)) {
ovlrd->opaquedir = NULL;
goto out_revert_creds;
}
}
@@ -1202,7 +1214,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
if (err)
goto out_revert_creds;
}
if (!overwrite && ovl_type_origin(new)) {
if (!ovlrd->overwrite && ovl_type_origin(new)) {
err = ovl_set_impure(old->d_parent, old_upperdir);
if (err)
goto out_revert_creds;
@@ -1212,7 +1224,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
rd.mnt_idmap = ovl_upper_mnt_idmap(ofs);
rd.old_parent = old_upperdir;
rd.new_parent = new_upperdir;
rd.flags = flags;
rd.flags = ovlrd->flags;
err = start_renaming(&rd, 0,
&QSTR_LEN(old->d_name.name, old->d_name.len),
@@ -1230,8 +1242,8 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
err = -ESTALE;
if (d_inode(new) && ovl_dentry_upper(new)) {
if (opaquedir) {
if (rd.new_dentry != opaquedir)
if (ovlrd->opaquedir) {
if (rd.new_dentry != ovlrd->opaquedir)
goto out_unlock;
} else {
if (!ovl_matches_upper(new, rd.new_dentry))
@@ -1242,7 +1254,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
if (!new_opaque || !ovl_upper_is_whiteout(ofs, rd.new_dentry))
goto out_unlock;
} else {
if (flags & RENAME_EXCHANGE)
if (ovlrd->flags & RENAME_EXCHANGE)
goto out_unlock;
}
}
@@ -1258,9 +1270,9 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
if (err)
goto out_unlock;
if (!overwrite && ovl_type_merge_or_lower(new))
if (!ovlrd->overwrite && ovl_type_merge_or_lower(new))
err = ovl_set_redirect(new, samedir);
else if (!overwrite && new_is_dir && !new_opaque &&
else if (!ovlrd->overwrite && new_is_dir && !new_opaque &&
ovl_type_merge(old->d_parent))
err = ovl_set_opaque_xerr(new, rd.new_dentry, -EXDEV);
if (err)
@@ -1268,7 +1280,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
err = ovl_do_rename_rd(&rd);
if (!err && cleanup_whiteout)
if (!err && ovlrd->cleanup_whiteout)
whiteout = dget(rd.new_dentry);
end_renaming(&rd);
@@ -1281,7 +1293,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
dput(whiteout);
}
if (overwrite && d_inode(new)) {
if (ovlrd->overwrite && d_inode(new)) {
if (new_is_dir)
clear_nlink(d_inode(new));
else
@@ -1289,7 +1301,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
}
ovl_dir_modified(old->d_parent, ovl_type_origin(old) ||
(!overwrite && ovl_type_origin(new)));
(!ovlrd->overwrite && ovl_type_origin(new)));
ovl_dir_modified(new->d_parent, ovl_type_origin(old) ||
(d_inode(new) && ovl_type_origin(new)));
@@ -1300,12 +1312,12 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
out_revert_creds:
ovl_revert_creds(old_cred);
if (update_nlink)
if (ovlrd->update_nlink)
ovl_nlink_end(new);
else
ovl_drop_write(old);
out:
dput(opaquedir);
dput(ovlrd->opaquedir);
ovl_cache_free(&list);
return err;