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-rw-r--r--fs/overlayfs/copy_up.c48
-rw-r--r--fs/overlayfs/dir.c241
-rw-r--r--fs/overlayfs/overlayfs.h23
-rw-r--r--fs/overlayfs/ovl_entry.h1
-rw-r--r--fs/overlayfs/params.c2
-rw-r--r--fs/overlayfs/readdir.c42
-rw-r--r--fs/overlayfs/super.c48
-rw-r--r--fs/overlayfs/util.c29
8 files changed, 235 insertions, 199 deletions
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 8a3c0d18ec2e..c4d7c281d473 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -517,15 +517,12 @@ static int ovl_set_upper_fh(struct ovl_fs *ofs, struct dentry *upper,
/*
* Create and install index entry.
- *
- * Caller must hold i_mutex on indexdir.
*/
static int ovl_create_index(struct dentry *dentry, const struct ovl_fh *fh,
struct dentry *upper)
{
struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
struct dentry *indexdir = ovl_indexdir(dentry->d_sb);
- struct inode *dir = d_inode(indexdir);
struct dentry *index = NULL;
struct dentry *temp = NULL;
struct qstr name = { };
@@ -559,6 +556,9 @@ static int ovl_create_index(struct dentry *dentry, const struct ovl_fh *fh,
if (err)
goto out;
+ err = ovl_parent_lock(indexdir, temp);
+ if (err)
+ goto out;
index = ovl_lookup_upper(ofs, name.name, indexdir, name.len);
if (IS_ERR(index)) {
err = PTR_ERR(index);
@@ -566,9 +566,10 @@ static int ovl_create_index(struct dentry *dentry, const struct ovl_fh *fh,
err = ovl_do_rename(ofs, indexdir, temp, indexdir, index, 0);
dput(index);
}
+ ovl_parent_unlock(indexdir);
out:
if (err)
- ovl_cleanup(ofs, dir, temp);
+ ovl_cleanup(ofs, indexdir, temp);
dput(temp);
free_name:
kfree(name.name);
@@ -762,7 +763,6 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
{
struct ovl_fs *ofs = OVL_FS(c->dentry->d_sb);
struct inode *inode;
- struct inode *wdir = d_inode(c->workdir);
struct path path = { .mnt = ovl_upper_mnt(ofs) };
struct dentry *temp, *upper, *trap;
struct ovl_cu_creds cc;
@@ -779,9 +779,7 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
return err;
ovl_start_write(c->dentry);
- inode_lock(wdir);
temp = ovl_create_temp(ofs, c->workdir, &cattr);
- inode_unlock(wdir);
ovl_end_write(c->dentry);
ovl_revert_cu_creds(&cc);
@@ -794,35 +792,36 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
*/
path.dentry = temp;
err = ovl_copy_up_data(c, &path);
+ ovl_start_write(c->dentry);
+ if (err)
+ goto cleanup_unlocked;
+
+ if (S_ISDIR(c->stat.mode) && c->indexed) {
+ err = ovl_create_index(c->dentry, c->origin_fh, temp);
+ if (err)
+ goto cleanup_unlocked;
+ }
+
/*
* We cannot hold lock_rename() throughout this helper, because of
* lock ordering with sb_writers, which shouldn't be held when calling
* ovl_copy_up_data(), so lock workdir and destdir and make sure that
* temp wasn't moved before copy up completion or cleanup.
*/
- ovl_start_write(c->dentry);
trap = lock_rename(c->workdir, c->destdir);
if (trap || temp->d_parent != c->workdir) {
/* temp or workdir moved underneath us? abort without cleanup */
dput(temp);
err = -EIO;
- if (IS_ERR(trap))
- goto out;
- goto unlock;
- } else if (err) {
- goto cleanup;
+ if (!IS_ERR(trap))
+ unlock_rename(c->workdir, c->destdir);
+ goto out;
}
err = ovl_copy_up_metadata(c, temp);
if (err)
goto cleanup;
- if (S_ISDIR(c->stat.mode) && c->indexed) {
- err = ovl_create_index(c->dentry, c->origin_fh, temp);
- if (err)
- goto cleanup;
- }
-
upper = ovl_lookup_upper(ofs, c->destname.name, c->destdir,
c->destname.len);
err = PTR_ERR(upper);
@@ -830,9 +829,10 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
goto cleanup;
err = ovl_do_rename(ofs, c->workdir, temp, c->destdir, upper, 0);
+ unlock_rename(c->workdir, c->destdir);
dput(upper);
if (err)
- goto cleanup;
+ goto cleanup_unlocked;
inode = d_inode(c->dentry);
if (c->metacopy_digest)
@@ -846,17 +846,17 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
ovl_inode_update(inode, temp);
if (S_ISDIR(inode->i_mode))
ovl_set_flag(OVL_WHITEOUTS, inode);
-unlock:
- unlock_rename(c->workdir, c->destdir);
out:
ovl_end_write(c->dentry);
return err;
cleanup:
- ovl_cleanup(ofs, wdir, temp);
+ unlock_rename(c->workdir, c->destdir);
+cleanup_unlocked:
+ ovl_cleanup(ofs, c->workdir, temp);
dput(temp);
- goto unlock;
+ goto out;
}
/* Copyup using O_TMPFILE which does not require cross dir locking */
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 4fc221ea6480..30619777f0f6 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -24,7 +24,8 @@ MODULE_PARM_DESC(redirect_max,
static int ovl_set_redirect(struct dentry *dentry, bool samedir);
-int ovl_cleanup(struct ovl_fs *ofs, struct inode *wdir, struct dentry *wdentry)
+static int ovl_cleanup_locked(struct ovl_fs *ofs, struct inode *wdir,
+ struct dentry *wdentry)
{
int err;
@@ -43,6 +44,21 @@ int ovl_cleanup(struct ovl_fs *ofs, struct inode *wdir, struct dentry *wdentry)
return err;
}
+int ovl_cleanup(struct ovl_fs *ofs, struct dentry *workdir,
+ struct dentry *wdentry)
+{
+ int err;
+
+ err = ovl_parent_lock(workdir, wdentry);
+ if (err)
+ return err;
+
+ ovl_cleanup_locked(ofs, workdir->d_inode, wdentry);
+ ovl_parent_unlock(workdir);
+
+ return 0;
+}
+
struct dentry *ovl_lookup_temp(struct ovl_fs *ofs, struct dentry *workdir)
{
struct dentry *temp;
@@ -62,7 +78,6 @@ struct dentry *ovl_lookup_temp(struct ovl_fs *ofs, struct dentry *workdir)
return temp;
}
-/* caller holds i_mutex on workdir */
static struct dentry *ovl_whiteout(struct ovl_fs *ofs)
{
int err;
@@ -70,47 +85,51 @@ static struct dentry *ovl_whiteout(struct ovl_fs *ofs)
struct dentry *workdir = ofs->workdir;
struct inode *wdir = workdir->d_inode;
+ guard(mutex)(&ofs->whiteout_lock);
+
if (!ofs->whiteout) {
+ inode_lock_nested(wdir, I_MUTEX_PARENT);
whiteout = ovl_lookup_temp(ofs, workdir);
- if (IS_ERR(whiteout))
- goto out;
-
- err = ovl_do_whiteout(ofs, wdir, whiteout);
- if (err) {
- dput(whiteout);
- whiteout = ERR_PTR(err);
- goto out;
+ if (!IS_ERR(whiteout)) {
+ err = ovl_do_whiteout(ofs, wdir, whiteout);
+ if (err) {
+ dput(whiteout);
+ whiteout = ERR_PTR(err);
+ }
}
+ inode_unlock(wdir);
+ if (IS_ERR(whiteout))
+ return whiteout;
ofs->whiteout = whiteout;
}
if (!ofs->no_shared_whiteout) {
+ inode_lock_nested(wdir, I_MUTEX_PARENT);
whiteout = ovl_lookup_temp(ofs, workdir);
- if (IS_ERR(whiteout))
- goto out;
-
- err = ovl_do_link(ofs, ofs->whiteout, wdir, whiteout);
- if (!err)
- goto out;
-
- if (err != -EMLINK) {
+ if (!IS_ERR(whiteout)) {
+ err = ovl_do_link(ofs, ofs->whiteout, wdir, whiteout);
+ if (err) {
+ dput(whiteout);
+ whiteout = ERR_PTR(err);
+ }
+ }
+ inode_unlock(wdir);
+ if (!IS_ERR(whiteout))
+ return whiteout;
+ if (PTR_ERR(whiteout) != -EMLINK) {
pr_warn("Failed to link whiteout - disabling whiteout inode sharing(nlink=%u, err=%i)\n",
ofs->whiteout->d_inode->i_nlink, err);
ofs->no_shared_whiteout = true;
}
- dput(whiteout);
}
whiteout = ofs->whiteout;
ofs->whiteout = NULL;
-out:
return whiteout;
}
-/* Caller must hold i_mutex on both workdir and dir */
int ovl_cleanup_and_whiteout(struct ovl_fs *ofs, struct dentry *dir,
struct dentry *dentry)
{
- struct inode *wdir = ofs->workdir->d_inode;
struct dentry *whiteout;
int err;
int flags = 0;
@@ -123,24 +142,29 @@ int ovl_cleanup_and_whiteout(struct ovl_fs *ofs, struct dentry *dir,
if (d_is_dir(dentry))
flags = RENAME_EXCHANGE;
- err = ovl_do_rename(ofs, ofs->workdir, whiteout, dir, dentry, flags);
+ err = ovl_lock_rename_workdir(ofs->workdir, whiteout, dir, dentry);
+ if (!err) {
+ err = ovl_do_rename(ofs, ofs->workdir, whiteout, dir, dentry, flags);
+ unlock_rename(ofs->workdir, dir);
+ }
if (err)
goto kill_whiteout;
if (flags)
- ovl_cleanup(ofs, wdir, dentry);
+ ovl_cleanup(ofs, ofs->workdir, dentry);
out:
dput(whiteout);
return err;
kill_whiteout:
- ovl_cleanup(ofs, wdir, whiteout);
+ ovl_cleanup(ofs, ofs->workdir, whiteout);
goto out;
}
-struct dentry *ovl_create_real(struct ovl_fs *ofs, struct inode *dir,
+struct dentry *ovl_create_real(struct ovl_fs *ofs, struct dentry *parent,
struct dentry *newdentry, struct ovl_cattr *attr)
{
+ struct inode *dir = parent->d_inode;
int err;
if (IS_ERR(newdentry))
@@ -199,8 +223,12 @@ out:
struct dentry *ovl_create_temp(struct ovl_fs *ofs, struct dentry *workdir,
struct ovl_cattr *attr)
{
- return ovl_create_real(ofs, d_inode(workdir),
- ovl_lookup_temp(ofs, workdir), attr);
+ struct dentry *ret;
+ inode_lock(workdir->d_inode);
+ ret = ovl_create_real(ofs, workdir,
+ ovl_lookup_temp(ofs, workdir), attr);
+ inode_unlock(workdir->d_inode);
+ return ret;
}
static int ovl_set_opaque_xerr(struct dentry *dentry, struct dentry *upper,
@@ -303,13 +331,13 @@ static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
int err;
inode_lock_nested(udir, I_MUTEX_PARENT);
- newdentry = ovl_create_real(ofs, udir,
+ newdentry = ovl_create_real(ofs, upperdir,
ovl_lookup_upper(ofs, dentry->d_name.name,
upperdir, dentry->d_name.len),
attr);
- err = PTR_ERR(newdentry);
+ inode_unlock(udir);
if (IS_ERR(newdentry))
- goto out_unlock;
+ return PTR_ERR(newdentry);
if (ovl_type_merge(dentry->d_parent) && d_is_dir(newdentry) &&
!ovl_allow_offline_changes(ofs)) {
@@ -321,14 +349,12 @@ static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
err = ovl_instantiate(dentry, inode, newdentry, !!attr->hardlink, NULL);
if (err)
goto out_cleanup;
-out_unlock:
- inode_unlock(udir);
- return err;
+ return 0;
out_cleanup:
- ovl_cleanup(ofs, udir, newdentry);
+ ovl_cleanup(ofs, upperdir, newdentry);
dput(newdentry);
- goto out_unlock;
+ return err;
}
static struct dentry *ovl_clear_empty(struct dentry *dentry,
@@ -336,9 +362,7 @@ static struct dentry *ovl_clear_empty(struct dentry *dentry,
{
struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
struct dentry *workdir = ovl_workdir(dentry);
- struct inode *wdir = workdir->d_inode;
struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
- struct inode *udir = upperdir->d_inode;
struct path upperpath;
struct dentry *upper;
struct dentry *opaquedir;
@@ -348,27 +372,25 @@ static struct dentry *ovl_clear_empty(struct dentry *dentry,
if (WARN_ON(!workdir))
return ERR_PTR(-EROFS);
- err = ovl_lock_rename_workdir(workdir, upperdir);
- if (err)
- goto out;
-
ovl_path_upper(dentry, &upperpath);
err = vfs_getattr(&upperpath, &stat,
STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
if (err)
- goto out_unlock;
+ goto out;
err = -ESTALE;
if (!S_ISDIR(stat.mode))
- goto out_unlock;
+ goto out;
upper = upperpath.dentry;
- if (upper->d_parent->d_inode != udir)
- goto out_unlock;
opaquedir = ovl_create_temp(ofs, workdir, OVL_CATTR(stat.mode));
err = PTR_ERR(opaquedir);
if (IS_ERR(opaquedir))
- goto out_unlock;
+ goto out;
+
+ err = ovl_lock_rename_workdir(workdir, opaquedir, upperdir, upper);
+ if (err)
+ goto out_cleanup_unlocked;
err = ovl_copy_xattr(dentry->d_sb, &upperpath, opaquedir);
if (err)
@@ -385,12 +407,12 @@ static struct dentry *ovl_clear_empty(struct dentry *dentry,
goto out_cleanup;
err = ovl_do_rename(ofs, workdir, opaquedir, upperdir, upper, RENAME_EXCHANGE);
+ unlock_rename(workdir, upperdir);
if (err)
- goto out_cleanup;
+ goto out_cleanup_unlocked;
ovl_cleanup_whiteouts(ofs, upper, list);
- ovl_cleanup(ofs, wdir, upper);
- unlock_rename(workdir, upperdir);
+ ovl_cleanup(ofs, workdir, upper);
/* dentry's upper doesn't match now, get rid of it */
d_drop(dentry);
@@ -398,10 +420,10 @@ static struct dentry *ovl_clear_empty(struct dentry *dentry,
return opaquedir;
out_cleanup:
- ovl_cleanup(ofs, wdir, opaquedir);
- dput(opaquedir);
-out_unlock:
unlock_rename(workdir, upperdir);
+out_cleanup_unlocked:
+ ovl_cleanup(ofs, workdir, opaquedir);
+ dput(opaquedir);
out:
return ERR_PTR(err);
}
@@ -420,9 +442,7 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
{
struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
struct dentry *workdir = ovl_workdir(dentry);
- struct inode *wdir = workdir->d_inode;
struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
- struct inode *udir = upperdir->d_inode;
struct dentry *upper;
struct dentry *newdentry;
int err;
@@ -439,15 +459,11 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
return err;
}
- err = ovl_lock_rename_workdir(workdir, upperdir);
- if (err)
- goto out;
-
- upper = ovl_lookup_upper(ofs, dentry->d_name.name, upperdir,
- dentry->d_name.len);
+ upper = ovl_lookup_upper_unlocked(ofs, dentry->d_name.name, upperdir,
+ dentry->d_name.len);
err = PTR_ERR(upper);
if (IS_ERR(upper))
- goto out_unlock;
+ goto out;
err = -ESTALE;
if (d_is_negative(upper) || !ovl_upper_is_whiteout(ofs, upper))
@@ -458,6 +474,10 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
if (IS_ERR(newdentry))
goto out_dput;
+ err = ovl_lock_rename_workdir(workdir, newdentry, upperdir, upper);
+ if (err)
+ goto out_cleanup_unlocked;
+
/*
* mode could have been mutilated due to umask (e.g. sgid directory)
*/
@@ -493,25 +513,25 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
err = ovl_do_rename(ofs, workdir, newdentry, upperdir, upper,
RENAME_EXCHANGE);
+ unlock_rename(workdir, upperdir);
if (err)
- goto out_cleanup;
+ goto out_cleanup_unlocked;
- ovl_cleanup(ofs, wdir, upper);
+ ovl_cleanup(ofs, workdir, upper);
} else {
err = ovl_do_rename(ofs, workdir, newdentry, upperdir, upper, 0);
+ unlock_rename(workdir, upperdir);
if (err)
- goto out_cleanup;
+ goto out_cleanup_unlocked;
}
ovl_dir_modified(dentry->d_parent, false);
err = ovl_instantiate(dentry, inode, newdentry, hardlink, NULL);
if (err) {
- ovl_cleanup(ofs, udir, newdentry);
+ ovl_cleanup(ofs, upperdir, newdentry);
dput(newdentry);
}
out_dput:
dput(upper);
-out_unlock:
- unlock_rename(workdir, upperdir);
out:
if (!hardlink) {
posix_acl_release(acl);
@@ -520,7 +540,9 @@ out:
return err;
out_cleanup:
- ovl_cleanup(ofs, wdir, newdentry);
+ unlock_rename(workdir, upperdir);
+out_cleanup_unlocked:
+ ovl_cleanup(ofs, workdir, newdentry);
dput(newdentry);
goto out_dput;
}
@@ -757,15 +779,11 @@ static int ovl_remove_and_whiteout(struct dentry *dentry,
goto out;
}
- err = ovl_lock_rename_workdir(workdir, upperdir);
- if (err)
- goto out_dput;
-
- upper = ovl_lookup_upper(ofs, dentry->d_name.name, upperdir,
- dentry->d_name.len);
+ upper = ovl_lookup_upper_unlocked(ofs, dentry->d_name.name, upperdir,
+ dentry->d_name.len);
err = PTR_ERR(upper);
if (IS_ERR(upper))
- goto out_unlock;
+ goto out_dput;
err = -ESTALE;
if ((opaquedir && upper != opaquedir) ||
@@ -775,16 +793,12 @@ static int ovl_remove_and_whiteout(struct dentry *dentry,
}
err = ovl_cleanup_and_whiteout(ofs, upperdir, upper);
- if (err)
- goto out_d_drop;
+ if (!err)
+ ovl_dir_modified(dentry->d_parent, true);
- ovl_dir_modified(dentry->d_parent, true);
-out_d_drop:
d_drop(dentry);
out_dput_upper:
dput(upper);
-out_unlock:
- unlock_rename(workdir, upperdir);
out_dput:
dput(opaquedir);
out:
@@ -1069,9 +1083,9 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
int err;
struct dentry *old_upperdir;
struct dentry *new_upperdir;
- struct dentry *olddentry;
- struct dentry *newdentry;
- struct dentry *trap;
+ struct dentry *olddentry = NULL;
+ struct dentry *newdentry = NULL;
+ struct dentry *trap, *de;
bool old_opaque;
bool new_opaque;
bool cleanup_whiteout = false;
@@ -1184,21 +1198,23 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
goto out_revert_creds;
}
- olddentry = ovl_lookup_upper(ofs, old->d_name.name, old_upperdir,
- old->d_name.len);
- err = PTR_ERR(olddentry);
- if (IS_ERR(olddentry))
+ de = ovl_lookup_upper(ofs, old->d_name.name, old_upperdir,
+ old->d_name.len);
+ err = PTR_ERR(de);
+ if (IS_ERR(de))
goto out_unlock;
+ olddentry = de;
err = -ESTALE;
if (!ovl_matches_upper(old, olddentry))
- goto out_dput_old;
+ goto out_unlock;
- newdentry = ovl_lookup_upper(ofs, new->d_name.name, new_upperdir,
- new->d_name.len);
- err = PTR_ERR(newdentry);
- if (IS_ERR(newdentry))
- goto out_dput_old;
+ de = ovl_lookup_upper(ofs, new->d_name.name, new_upperdir,
+ new->d_name.len);
+ err = PTR_ERR(de);
+ if (IS_ERR(de))
+ goto out_unlock;
+ newdentry = de;
old_opaque = ovl_dentry_is_opaque(old);
new_opaque = ovl_dentry_is_opaque(new);
@@ -1207,28 +1223,28 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
if (d_inode(new) && ovl_dentry_upper(new)) {
if (opaquedir) {
if (newdentry != opaquedir)
- goto out_dput;
+ goto out_unlock;
} else {
if (!ovl_matches_upper(new, newdentry))
- goto out_dput;
+ goto out_unlock;
}
} else {
if (!d_is_negative(newdentry)) {
if (!new_opaque || !ovl_upper_is_whiteout(ofs, newdentry))
- goto out_dput;
+ goto out_unlock;
} else {
if (flags & RENAME_EXCHANGE)
- goto out_dput;
+ goto out_unlock;
}
}
if (olddentry == trap)
- goto out_dput;
+ goto out_unlock;
if (newdentry == trap)
- goto out_dput;
+ goto out_unlock;
if (olddentry->d_inode == newdentry->d_inode)
- goto out_dput;
+ goto out_unlock;
err = 0;
if (ovl_type_merge_or_lower(old))
@@ -1236,7 +1252,7 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
else if (is_dir && !old_opaque && ovl_type_merge(new->d_parent))
err = ovl_set_opaque_xerr(old, olddentry, -EXDEV);
if (err)
- goto out_dput;
+ goto out_unlock;
if (!overwrite && ovl_type_merge_or_lower(new))
err = ovl_set_redirect(new, samedir);
@@ -1244,15 +1260,16 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
ovl_type_merge(old->d_parent))
err = ovl_set_opaque_xerr(new, newdentry, -EXDEV);
if (err)
- goto out_dput;
+ goto out_unlock;
err = ovl_do_rename(ofs, old_upperdir, olddentry,
new_upperdir, newdentry, flags);
+ unlock_rename(new_upperdir, old_upperdir);
if (err)
- goto out_dput;
+ goto out_revert_creds;
if (cleanup_whiteout)
- ovl_cleanup(ofs, old_upperdir->d_inode, newdentry);
+ ovl_cleanup(ofs, old_upperdir, newdentry);
if (overwrite && d_inode(new)) {
if (new_is_dir)
@@ -1271,12 +1288,6 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
if (d_inode(new) && ovl_dentry_upper(new))
ovl_copyattr(d_inode(new));
-out_dput:
- dput(newdentry);
-out_dput_old:
- dput(olddentry);
-out_unlock:
- unlock_rename(new_upperdir, old_upperdir);
out_revert_creds:
ovl_revert_creds(old_cred);
if (update_nlink)
@@ -1284,9 +1295,15 @@ out_revert_creds:
else
ovl_drop_write(old);
out:
+ dput(newdentry);
+ dput(olddentry);
dput(opaquedir);
ovl_cache_free(&list);
return err;
+
+out_unlock:
+ unlock_rename(new_upperdir, old_upperdir);
+ goto out_revert_creds;
}
static int ovl_create_tmpfile(struct file *file, struct dentry *dentry,
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 3c52ecddfc9c..ab8f72d33bdf 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -405,6 +405,15 @@ static inline struct dentry *ovl_lookup_upper(struct ovl_fs *ofs,
return lookup_one(ovl_upper_mnt_idmap(ofs), &QSTR_LEN(name, len), base);
}
+static inline struct dentry *ovl_lookup_upper_unlocked(struct ovl_fs *ofs,
+ const char *name,
+ struct dentry *base,
+ int len)
+{
+ return lookup_one_unlocked(ovl_upper_mnt_idmap(ofs),
+ &QSTR_LEN(name, len), base);
+}
+
static inline bool ovl_open_flags_need_copy_up(int flags)
{
if (!flags)
@@ -414,6 +423,11 @@ static inline bool ovl_open_flags_need_copy_up(int flags)
}
/* util.c */
+int ovl_parent_lock(struct dentry *parent, struct dentry *child);
+static inline void ovl_parent_unlock(struct dentry *parent)
+{
+ inode_unlock(parent->d_inode);
+}
int ovl_get_write_access(struct dentry *dentry);
void ovl_put_write_access(struct dentry *dentry);
void ovl_start_write(struct dentry *dentry);
@@ -539,7 +553,8 @@ bool ovl_is_inuse(struct dentry *dentry);
bool ovl_need_index(struct dentry *dentry);
int ovl_nlink_start(struct dentry *dentry);
void ovl_nlink_end(struct dentry *dentry);
-int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir);
+int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *work,
+ struct dentry *upperdir, struct dentry *upper);
int ovl_check_metacopy_xattr(struct ovl_fs *ofs, const struct path *path,
struct ovl_metacopy *data);
int ovl_set_metacopy_xattr(struct ovl_fs *ofs, struct dentry *d,
@@ -727,7 +742,7 @@ void ovl_cleanup_whiteouts(struct ovl_fs *ofs, struct dentry *upper,
void ovl_cache_free(struct list_head *list);
void ovl_dir_cache_free(struct inode *inode);
int ovl_check_d_type_supported(const struct path *realpath);
-int ovl_workdir_cleanup(struct ovl_fs *ofs, struct inode *dir,
+int ovl_workdir_cleanup(struct ovl_fs *ofs, struct dentry *parent,
struct vfsmount *mnt, struct dentry *dentry, int level);
int ovl_indexdir_cleanup(struct ovl_fs *ofs);
@@ -844,9 +859,9 @@ struct ovl_cattr {
#define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
struct dentry *ovl_create_real(struct ovl_fs *ofs,
- struct inode *dir, struct dentry *newdentry,
+ struct dentry *parent, struct dentry *newdentry,
struct ovl_cattr *attr);
-int ovl_cleanup(struct ovl_fs *ofs, struct inode *dir, struct dentry *dentry);
+int ovl_cleanup(struct ovl_fs *ofs, struct dentry *workdir, struct dentry *dentry);
struct dentry *ovl_lookup_temp(struct ovl_fs *ofs, struct dentry *workdir);
struct dentry *ovl_create_temp(struct ovl_fs *ofs, struct dentry *workdir,
struct ovl_cattr *attr);
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index afb7762f873f..4c1bae935ced 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -88,6 +88,7 @@ struct ovl_fs {
/* Shared whiteout cache */
struct dentry *whiteout;
bool no_shared_whiteout;
+ struct mutex whiteout_lock;
/* r/o snapshot of upperdir sb's only taken on volatile mounts */
errseq_t errseq;
};
diff --git a/fs/overlayfs/params.c b/fs/overlayfs/params.c
index 2b9b31524c38..f4e7fff909ac 100644
--- a/fs/overlayfs/params.c
+++ b/fs/overlayfs/params.c
@@ -795,6 +795,8 @@ int ovl_init_fs_context(struct fs_context *fc)
fc->s_fs_info = ofs;
fc->fs_private = ctx;
fc->ops = &ovl_context_ops;
+
+ mutex_init(&ofs->whiteout_lock);
return 0;
out_err:
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 68cca52ae2ac..b65cdfce31ce 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -1034,14 +1034,13 @@ void ovl_cleanup_whiteouts(struct ovl_fs *ofs, struct dentry *upper,
{
struct ovl_cache_entry *p;
- inode_lock_nested(upper->d_inode, I_MUTEX_CHILD);
list_for_each_entry(p, list, l_node) {
struct dentry *dentry;
if (WARN_ON(!p->is_whiteout || !p->is_upper))
continue;
- dentry = ovl_lookup_upper(ofs, p->name, upper, p->len);
+ dentry = ovl_lookup_upper_unlocked(ofs, p->name, upper, p->len);
if (IS_ERR(dentry)) {
pr_err("lookup '%s/%.*s' failed (%i)\n",
upper->d_name.name, p->len, p->name,
@@ -1049,10 +1048,9 @@ void ovl_cleanup_whiteouts(struct ovl_fs *ofs, struct dentry *upper,
continue;
}
if (dentry->d_inode)
- ovl_cleanup(ofs, upper->d_inode, dentry);
+ ovl_cleanup(ofs, upper, dentry);
dput(dentry);
}
- inode_unlock(upper->d_inode);
}
static bool ovl_check_d_type(struct dir_context *ctx, const char *name,
@@ -1098,7 +1096,6 @@ static int ovl_workdir_cleanup_recurse(struct ovl_fs *ofs, const struct path *pa
int level)
{
int err;
- struct inode *dir = path->dentry->d_inode;
LIST_HEAD(list);
struct ovl_cache_entry *p;
struct ovl_readdir_data rdd = {
@@ -1124,7 +1121,6 @@ static int ovl_workdir_cleanup_recurse(struct ovl_fs *ofs, const struct path *pa
if (err)
goto out;
- inode_lock_nested(dir, I_MUTEX_PARENT);
list_for_each_entry(p, &list, l_node) {
struct dentry *dentry;
@@ -1139,39 +1135,40 @@ static int ovl_workdir_cleanup_recurse(struct ovl_fs *ofs, const struct path *pa
err = -EINVAL;
break;
}
- dentry = ovl_lookup_upper(ofs, p->name, path->dentry, p->len);
+ dentry = ovl_lookup_upper_unlocked(ofs, p->name, path->dentry, p->len);
if (IS_ERR(dentry))
continue;
if (dentry->d_inode)
- err = ovl_workdir_cleanup(ofs, dir, path->mnt, dentry, level);
+ err = ovl_workdir_cleanup(ofs, path->dentry, path->mnt,
+ dentry, level);
dput(dentry);
if (err)
break;
}
- inode_unlock(dir);
out:
ovl_cache_free(&list);
return err;
}
-int ovl_workdir_cleanup(struct ovl_fs *ofs, struct inode *dir,
+int ovl_workdir_cleanup(struct ovl_fs *ofs, struct dentry *parent,
struct vfsmount *mnt, struct dentry *dentry, int level)
{
int err;
- if (!d_is_dir(dentry) || level > 1) {
- return ovl_cleanup(ofs, dir, dentry);
- }
+ if (!d_is_dir(dentry) || level > 1)
+ return ovl_cleanup(ofs, parent, dentry);
- err = ovl_do_rmdir(ofs, dir, dentry);
+ err = ovl_parent_lock(parent, dentry);
+ if (err)
+ return err;
+ err = ovl_do_rmdir(ofs, parent->d_inode, dentry);
+ ovl_parent_unlock(parent);
if (err) {
struct path path = { .mnt = mnt, .dentry = dentry };
- inode_unlock(dir);
err = ovl_workdir_cleanup_recurse(ofs, &path, level + 1);
- inode_lock_nested(dir, I_MUTEX_PARENT);
if (!err)
- err = ovl_cleanup(ofs, dir, dentry);
+ err = ovl_cleanup(ofs, parent, dentry);
}
return err;
@@ -1182,7 +1179,6 @@ int ovl_indexdir_cleanup(struct ovl_fs *ofs)
int err;
struct dentry *indexdir = ofs->workdir;
struct dentry *index = NULL;
- struct inode *dir = indexdir->d_inode;
struct path path = { .mnt = ovl_upper_mnt(ofs), .dentry = indexdir };
LIST_HEAD(list);
struct ovl_cache_entry *p;
@@ -1196,7 +1192,6 @@ int ovl_indexdir_cleanup(struct ovl_fs *ofs)
if (err)
goto out;
- inode_lock_nested(dir, I_MUTEX_PARENT);
list_for_each_entry(p, &list, l_node) {
if (p->name[0] == '.') {
if (p->len == 1)
@@ -1204,7 +1199,7 @@ int ovl_indexdir_cleanup(struct ovl_fs *ofs)
if (p->len == 2 && p->name[1] == '.')
continue;
}
- index = ovl_lookup_upper(ofs, p->name, indexdir, p->len);
+ index = ovl_lookup_upper_unlocked(ofs, p->name, indexdir, p->len);
if (IS_ERR(index)) {
err = PTR_ERR(index);
index = NULL;
@@ -1212,7 +1207,7 @@ int ovl_indexdir_cleanup(struct ovl_fs *ofs)
}
/* Cleanup leftover from index create/cleanup attempt */
if (index->d_name.name[0] == '#') {
- err = ovl_workdir_cleanup(ofs, dir, path.mnt, index, 1);
+ err = ovl_workdir_cleanup(ofs, indexdir, path.mnt, index, 1);
if (err)
break;
goto next;
@@ -1222,7 +1217,7 @@ int ovl_indexdir_cleanup(struct ovl_fs *ofs)
goto next;
} else if (err == -ESTALE) {
/* Cleanup stale index entries */
- err = ovl_cleanup(ofs, dir, index);
+ err = ovl_cleanup(ofs, indexdir, index);
} else if (err != -ENOENT) {
/*
* Abort mount to avoid corrupting the index if
@@ -1238,7 +1233,7 @@ int ovl_indexdir_cleanup(struct ovl_fs *ofs)
err = ovl_cleanup_and_whiteout(ofs, indexdir, index);
} else {
/* Cleanup orphan index entries */
- err = ovl_cleanup(ofs, dir, index);
+ err = ovl_cleanup(ofs, indexdir, index);
}
if (err)
@@ -1249,7 +1244,6 @@ next:
index = NULL;
}
dput(index);
- inode_unlock(dir);
out:
ovl_cache_free(&list);
if (err)
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index cf99b276fdfb..4afa91882075 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -299,8 +299,8 @@ static struct dentry *ovl_workdir_create(struct ovl_fs *ofs,
int err;
bool retried = false;
- inode_lock_nested(dir, I_MUTEX_PARENT);
retry:
+ inode_lock_nested(dir, I_MUTEX_PARENT);
work = ovl_lookup_upper(ofs, name, ofs->workbasedir, strlen(name));
if (!IS_ERR(work)) {
@@ -311,23 +311,24 @@ retry:
if (work->d_inode) {
err = -EEXIST;
+ inode_unlock(dir);
if (retried)
goto out_dput;
if (persist)
- goto out_unlock;
+ return work;
retried = true;
- err = ovl_workdir_cleanup(ofs, dir, mnt, work, 0);
+ err = ovl_workdir_cleanup(ofs, ofs->workbasedir, mnt, work, 0);
dput(work);
- if (err == -EINVAL) {
- work = ERR_PTR(err);
- goto out_unlock;
- }
+ if (err == -EINVAL)
+ return ERR_PTR(err);
+
goto retry;
}
work = ovl_do_mkdir(ofs, dir, work, attr.ia_mode);
+ inode_unlock(dir);
err = PTR_ERR(work);
if (IS_ERR(work))
goto out_err;
@@ -365,11 +366,10 @@ retry:
if (err)
goto out_dput;
} else {
+ inode_unlock(dir);
err = PTR_ERR(work);
goto out_err;
}
-out_unlock:
- inode_unlock(dir);
return work;
out_dput:
@@ -377,8 +377,7 @@ out_dput:
out_err:
pr_warn("failed to create directory %s/%s (errno: %i); mounting read-only\n",
ofs->config.workdir, name, -err);
- work = NULL;
- goto out_unlock;
+ return NULL;
}
static int ovl_check_namelen(const struct path *path, struct ovl_fs *ofs,
@@ -557,37 +556,42 @@ out:
static int ovl_check_rename_whiteout(struct ovl_fs *ofs)
{
struct dentry *workdir = ofs->workdir;
- struct inode *dir = d_inode(workdir);
struct dentry *temp;
struct dentry *dest;
struct dentry *whiteout;
struct name_snapshot name;
int err;
- inode_lock_nested(dir, I_MUTEX_PARENT);
-
temp = ovl_create_temp(ofs, workdir, OVL_CATTR(S_IFREG | 0));
err = PTR_ERR(temp);
if (IS_ERR(temp))
- goto out_unlock;
+ return err;
+ err = ovl_parent_lock(workdir, temp);
+ if (err) {
+ dput(temp);
+ return err;
+ }
dest = ovl_lookup_temp(ofs, workdir);
err = PTR_ERR(dest);
if (IS_ERR(dest)) {
dput(temp);
- goto out_unlock;
+ ovl_parent_unlock(workdir);
+ return err;
}
/* Name is inline and stable - using snapshot as a copy helper */
take_dentry_name_snapshot(&name, temp);
err = ovl_do_rename(ofs, workdir, temp, workdir, dest, RENAME_WHITEOUT);
+ ovl_parent_unlock(workdir);
if (err) {
if (err == -EINVAL)
err = 0;
goto cleanup_temp;
}
- whiteout = ovl_lookup_upper(ofs, name.name.name, workdir, name.name.len);
+ whiteout = ovl_lookup_upper_unlocked(ofs, name.name.name,
+ workdir, name.name.len);
err = PTR_ERR(whiteout);
if (IS_ERR(whiteout))
goto cleanup_temp;
@@ -596,18 +600,15 @@ static int ovl_check_rename_whiteout(struct ovl_fs *ofs)
/* Best effort cleanup of whiteout and temp file */
if (err)
- ovl_cleanup(ofs, dir, whiteout);
+ ovl_cleanup(ofs, workdir, whiteout);
dput(whiteout);
cleanup_temp:
- ovl_cleanup(ofs, dir, temp);
+ ovl_cleanup(ofs, workdir, temp);
release_dentry_name_snapshot(&name);
dput(temp);
dput(dest);
-out_unlock:
- inode_unlock(dir);
-
return err;
}
@@ -621,8 +622,7 @@ static struct dentry *ovl_lookup_or_create(struct ovl_fs *ofs,
inode_lock_nested(parent->d_inode, I_MUTEX_PARENT);
child = ovl_lookup_upper(ofs, name, parent, len);
if (!IS_ERR(child) && !child->d_inode)
- child = ovl_create_real(ofs, parent->d_inode, child,
- OVL_CATTR(mode));
+ child = ovl_create_real(ofs, parent, child, OVL_CATTR(mode));
inode_unlock(parent->d_inode);
dput(parent);
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index cc793c8f001f..71674b633bc4 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -1078,7 +1078,6 @@ 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;
@@ -1114,8 +1113,7 @@ static void ovl_cleanup_index(struct dentry *dentry)
goto out;
}
- inode_lock_nested(dir, I_MUTEX_PARENT);
- index = ovl_lookup_upper(ofs, name.name, indexdir, name.len);
+ index = ovl_lookup_upper_unlocked(ofs, name.name, indexdir, name.len);
err = PTR_ERR(index);
if (IS_ERR(index)) {
index = NULL;
@@ -1125,10 +1123,8 @@ static void ovl_cleanup_index(struct dentry *dentry)
indexdir, index);
} else {
/* Cleanup orphan index entries */
- err = ovl_cleanup(ofs, dir, index);
+ err = ovl_cleanup(ofs, indexdir, index);
}
-
- inode_unlock(dir);
if (err)
goto fail;
@@ -1227,20 +1223,21 @@ void ovl_nlink_end(struct dentry *dentry)
ovl_inode_unlock(inode);
}
-int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)
+int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *work,
+ struct dentry *upperdir, struct dentry *upper)
{
struct dentry *trap;
- /* Workdir should not be the same as upperdir */
- if (workdir == upperdir)
- goto err;
-
/* Workdir should not be subdir of upperdir and vice versa */
trap = lock_rename(workdir, upperdir);
if (IS_ERR(trap))
goto err;
if (trap)
goto err_unlock;
+ if (work && work->d_parent != workdir)
+ goto err_unlock;
+ if (upper && upper->d_parent != upperdir)
+ goto err_unlock;
return 0;
@@ -1551,3 +1548,13 @@ void ovl_copyattr(struct inode *inode)
i_size_write(inode, i_size_read(realinode));
spin_unlock(&inode->i_lock);
}
+
+int ovl_parent_lock(struct dentry *parent, struct dentry *child)
+{
+ inode_lock_nested(parent->d_inode, I_MUTEX_PARENT);
+ if (!child || child->d_parent == parent)
+ return 0;
+
+ inode_unlock(parent->d_inode);
+ return -EINVAL;
+}
generated by cgit (git 2.34.1) at 2025-08-09 10:24:01 +0000