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path: root/fs/overlayfs/namei.c
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Diffstat (limited to 'fs/overlayfs/namei.c')
-rw-r--r--fs/overlayfs/namei.c91
1 files changed, 63 insertions, 28 deletions
diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index 80391c687..22c29e540 100644
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -18,10 +18,11 @@
struct ovl_lookup_data {
struct super_block *sb;
- struct vfsmount *mnt;
+ const struct ovl_layer *layer;
struct qstr name;
bool is_dir;
bool opaque;
+ bool xwhiteouts;
bool stop;
bool last;
char *redirect;
@@ -201,17 +202,13 @@ struct dentry *ovl_decode_real_fh(struct ovl_fs *ofs, struct ovl_fh *fh,
return real;
}
-static bool ovl_is_opaquedir(struct ovl_fs *ofs, const struct path *path)
-{
- return ovl_path_check_dir_xattr(ofs, path, OVL_XATTR_OPAQUE);
-}
-
static struct dentry *ovl_lookup_positive_unlocked(struct ovl_lookup_data *d,
const char *name,
struct dentry *base, int len,
bool drop_negative)
{
- struct dentry *ret = lookup_one_unlocked(mnt_idmap(d->mnt), name, base, len);
+ struct dentry *ret = lookup_one_unlocked(mnt_idmap(d->layer->mnt), name,
+ base, len);
if (!IS_ERR(ret) && d_flags_negative(smp_load_acquire(&ret->d_flags))) {
if (drop_negative && ret->d_lockref.count == 1) {
@@ -232,10 +229,13 @@ static int ovl_lookup_single(struct dentry *base, struct ovl_lookup_data *d,
size_t prelen, const char *post,
struct dentry **ret, bool drop_negative)
{
+ struct ovl_fs *ofs = OVL_FS(d->sb);
struct dentry *this;
struct path path;
int err;
bool last_element = !post[0];
+ bool is_upper = d->layer->idx == 0;
+ char val;
this = ovl_lookup_positive_unlocked(d, name, base, namelen, drop_negative);
if (IS_ERR(this)) {
@@ -251,7 +251,10 @@ static int ovl_lookup_single(struct dentry *base, struct ovl_lookup_data *d,
err = -EREMOTE;
goto out_err;
}
- if (ovl_is_whiteout(this)) {
+
+ path.dentry = this;
+ path.mnt = d->layer->mnt;
+ if (ovl_path_is_whiteout(ofs, &path)) {
d->stop = d->opaque = true;
goto put_and_out;
}
@@ -264,14 +267,12 @@ static int ovl_lookup_single(struct dentry *base, struct ovl_lookup_data *d,
goto put_and_out;
}
- path.dentry = this;
- path.mnt = d->mnt;
if (!d_can_lookup(this)) {
if (d->is_dir || !last_element) {
d->stop = true;
goto put_and_out;
}
- err = ovl_check_metacopy_xattr(OVL_FS(d->sb), &path, NULL);
+ err = ovl_check_metacopy_xattr(ofs, &path, NULL);
if (err < 0)
goto out_err;
@@ -291,7 +292,12 @@ static int ovl_lookup_single(struct dentry *base, struct ovl_lookup_data *d,
if (d->last)
goto out;
- if (ovl_is_opaquedir(OVL_FS(d->sb), &path)) {
+ /* overlay.opaque=x means xwhiteouts directory */
+ val = ovl_get_opaquedir_val(ofs, &path);
+ if (last_element && !is_upper && val == 'x') {
+ d->xwhiteouts = true;
+ ovl_layer_set_xwhiteouts(ofs, d->layer);
+ } else if (val == 'y') {
d->stop = true;
if (last_element)
d->opaque = true;
@@ -438,7 +444,7 @@ int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
else if (IS_ERR(origin))
return PTR_ERR(origin);
- if (upperdentry && !ovl_is_whiteout(upperdentry) &&
+ if (upperdentry && !ovl_upper_is_whiteout(ofs, upperdentry) &&
inode_wrong_type(d_inode(upperdentry), d_inode(origin)->i_mode))
goto invalid;
@@ -507,6 +513,19 @@ static int ovl_verify_fh(struct ovl_fs *ofs, struct dentry *dentry,
return err;
}
+int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
+ enum ovl_xattr ox, const struct ovl_fh *fh,
+ bool is_upper, bool set)
+{
+ int err;
+
+ err = ovl_verify_fh(ofs, dentry, ox, fh);
+ if (set && err == -ENODATA)
+ err = ovl_setxattr(ofs, dentry, ox, fh->buf, fh->fb.len);
+
+ return err;
+}
+
/*
* Verify that @real dentry matches the file handle stored in xattr @name.
*
@@ -515,9 +534,9 @@ static int ovl_verify_fh(struct ovl_fs *ofs, struct dentry *dentry,
*
* Return 0 on match, -ESTALE on mismatch, -ENODATA on no xattr, < 0 on error.
*/
-int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
- enum ovl_xattr ox, struct dentry *real, bool is_upper,
- bool set)
+int ovl_verify_origin_xattr(struct ovl_fs *ofs, struct dentry *dentry,
+ enum ovl_xattr ox, struct dentry *real,
+ bool is_upper, bool set)
{
struct inode *inode;
struct ovl_fh *fh;
@@ -530,9 +549,7 @@ int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
goto fail;
}
- err = ovl_verify_fh(ofs, dentry, ox, fh);
- if (set && err == -ENODATA)
- err = ovl_setxattr(ofs, dentry, ox, fh->buf, fh->fb.len);
+ err = ovl_verify_set_fh(ofs, dentry, ox, fh, is_upper, set);
if (err)
goto fail;
@@ -548,6 +565,7 @@ fail:
goto out;
}
+
/* Get upper dentry from index */
struct dentry *ovl_index_upper(struct ovl_fs *ofs, struct dentry *index,
bool connected)
@@ -684,7 +702,7 @@ orphan:
goto out;
}
-static int ovl_get_index_name_fh(struct ovl_fh *fh, struct qstr *name)
+int ovl_get_index_name_fh(const struct ovl_fh *fh, struct qstr *name)
{
char *n, *s;
@@ -850,7 +868,8 @@ fail:
* Returns next layer in stack starting from top.
* Returns -1 if this is the last layer.
*/
-int ovl_path_next(int idx, struct dentry *dentry, struct path *path)
+int ovl_path_next(int idx, struct dentry *dentry, struct path *path,
+ const struct ovl_layer **layer)
{
struct ovl_entry *oe = OVL_E(dentry);
struct ovl_path *lowerstack = ovl_lowerstack(oe);
@@ -858,13 +877,16 @@ int ovl_path_next(int idx, struct dentry *dentry, struct path *path)
BUG_ON(idx < 0);
if (idx == 0) {
ovl_path_upper(dentry, path);
- if (path->dentry)
+ if (path->dentry) {
+ *layer = &OVL_FS(dentry->d_sb)->layers[0];
return ovl_numlower(oe) ? 1 : -1;
+ }
idx++;
}
BUG_ON(idx > ovl_numlower(oe));
path->dentry = lowerstack[idx - 1].dentry;
- path->mnt = lowerstack[idx - 1].layer->mnt;
+ *layer = lowerstack[idx - 1].layer;
+ path->mnt = (*layer)->mnt;
return (idx < ovl_numlower(oe)) ? idx + 1 : -1;
}
@@ -873,20 +895,27 @@ int ovl_path_next(int idx, struct dentry *dentry, struct path *path)
static int ovl_fix_origin(struct ovl_fs *ofs, struct dentry *dentry,
struct dentry *lower, struct dentry *upper)
{
+ const struct ovl_fh *fh;
int err;
if (ovl_check_origin_xattr(ofs, upper))
return 0;
+ fh = ovl_get_origin_fh(ofs, lower);
+ if (IS_ERR(fh))
+ return PTR_ERR(fh);
+
err = ovl_want_write(dentry);
if (err)
- return err;
+ goto out;
- err = ovl_set_origin(ofs, lower, upper);
+ err = ovl_set_origin_fh(ofs, fh, upper);
if (!err)
err = ovl_set_impure(dentry->d_parent, upper->d_parent);
ovl_drop_write(dentry);
+out:
+ kfree(fh);
return err;
}
@@ -1035,7 +1064,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
old_cred = ovl_override_creds(dentry->d_sb);
upperdir = ovl_dentry_upper(dentry->d_parent);
if (upperdir) {
- d.mnt = ovl_upper_mnt(ofs);
+ d.layer = &ofs->layers[0];
err = ovl_lookup_layer(upperdir, &d, &upperdentry, true);
if (err)
goto out;
@@ -1091,7 +1120,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
else if (d.is_dir || !ofs->numdatalayer)
d.last = lower.layer->idx == ovl_numlower(roe);
- d.mnt = lower.layer->mnt;
+ d.layer = lower.layer;
err = ovl_lookup_layer(lower.dentry, &d, &this, false);
if (err)
goto out_put;
@@ -1258,6 +1287,8 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
if (upperopaque)
ovl_dentry_set_opaque(dentry);
+ if (d.xwhiteouts)
+ ovl_dentry_set_xwhiteouts(dentry);
if (upperdentry)
ovl_dentry_set_upper_alias(dentry);
@@ -1383,7 +1414,11 @@ bool ovl_lower_positive(struct dentry *dentry)
break;
}
} else {
- positive = !ovl_is_whiteout(this);
+ struct path path = {
+ .dentry = this,
+ .mnt = parentpath->layer->mnt,
+ };
+ positive = !ovl_path_is_whiteout(OVL_FS(dentry->d_sb), &path);
done = true;
dput(this);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-16 06:27:53 +0000