42f559ed70
First two patches weren't marked for stable but are dependencies for
laters ones. The rest of patches was marked for stable but most likely
will be backported to 4.5+ only so we need to get them on our own.
An important fix is eea2fb4851e9d ("ovl: proper cleanup of workdir") as
it allows mounting overlayfs with dirty workdir, e.g. after power cut.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
131 lines
3.9 KiB
Diff
131 lines
3.9 KiB
Diff
From eea2fb4851e9dcbab6b991aaf47e2e024f1f55a0 Mon Sep 17 00:00:00 2001
|
|
From: Miklos Szeredi <mszeredi@redhat.com>
|
|
Date: Thu, 1 Sep 2016 11:11:59 +0200
|
|
Subject: [PATCH] ovl: proper cleanup of workdir
|
|
|
|
When mounting overlayfs it needs a clean "work" directory under the
|
|
supplied workdir.
|
|
|
|
Previously the mount code removed this directory if it already existed and
|
|
created a new one. If the removal failed (e.g. directory was not empty)
|
|
then it fell back to a read-only mount not using the workdir.
|
|
|
|
While this has never been reported, it is possible to get a non-empty
|
|
"work" dir from a previous mount of overlayfs in case of crash in the
|
|
middle of an operation using the work directory.
|
|
|
|
In this case the left over state should be discarded and the overlay
|
|
filesystem will be consistent, guaranteed by the atomicity of operations on
|
|
moving to/from the workdir to the upper layer.
|
|
|
|
This patch implements cleaning out any files left in workdir. It is
|
|
implemented using real recursion for simplicity, but the depth is limited
|
|
to 2, because the worst case is that of a directory containing whiteouts
|
|
under "work".
|
|
|
|
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
|
|
Cc: <stable@vger.kernel.org>
|
|
---
|
|
fs/overlayfs/overlayfs.h | 2 ++
|
|
fs/overlayfs/readdir.c | 63 +++++++++++++++++++++++++++++++++++++++++++++++-
|
|
fs/overlayfs/super.c | 2 +-
|
|
3 files changed, 65 insertions(+), 2 deletions(-)
|
|
|
|
--- a/fs/overlayfs/overlayfs.h
|
|
+++ b/fs/overlayfs/overlayfs.h
|
|
@@ -164,6 +164,8 @@ extern const struct file_operations ovl_
|
|
int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list);
|
|
void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list);
|
|
void ovl_cache_free(struct list_head *list);
|
|
+void ovl_workdir_cleanup(struct inode *dir, struct vfsmount *mnt,
|
|
+ struct dentry *dentry, int level);
|
|
|
|
/* inode.c */
|
|
int ovl_setattr(struct dentry *dentry, struct iattr *attr);
|
|
--- a/fs/overlayfs/readdir.c
|
|
+++ b/fs/overlayfs/readdir.c
|
|
@@ -247,7 +247,7 @@ static inline int ovl_dir_read(struct pa
|
|
err = rdd->err;
|
|
} while (!err && rdd->count);
|
|
|
|
- if (!err && rdd->first_maybe_whiteout)
|
|
+ if (!err && rdd->first_maybe_whiteout && rdd->dentry)
|
|
err = ovl_check_whiteouts(realpath->dentry, rdd);
|
|
|
|
fput(realfile);
|
|
@@ -569,3 +569,64 @@ void ovl_cleanup_whiteouts(struct dentry
|
|
}
|
|
mutex_unlock(&upper->d_inode->i_mutex);
|
|
}
|
|
+
|
|
+static void ovl_workdir_cleanup_recurse(struct path *path, int level)
|
|
+{
|
|
+ int err;
|
|
+ struct inode *dir = path->dentry->d_inode;
|
|
+ LIST_HEAD(list);
|
|
+ struct ovl_cache_entry *p;
|
|
+ struct ovl_readdir_data rdd = {
|
|
+ .ctx.actor = ovl_fill_merge,
|
|
+ .dentry = NULL,
|
|
+ .list = &list,
|
|
+ .root = RB_ROOT,
|
|
+ .is_lowest = false,
|
|
+ };
|
|
+
|
|
+ err = ovl_dir_read(path, &rdd);
|
|
+ if (err)
|
|
+ goto out;
|
|
+
|
|
+ mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
|
|
+ list_for_each_entry(p, &list, l_node) {
|
|
+ struct dentry *dentry;
|
|
+
|
|
+ if (p->name[0] == '.') {
|
|
+ if (p->len == 1)
|
|
+ continue;
|
|
+ if (p->len == 2 && p->name[1] == '.')
|
|
+ continue;
|
|
+ }
|
|
+ dentry = lookup_one_len(p->name, path->dentry, p->len);
|
|
+ if (IS_ERR(dentry))
|
|
+ continue;
|
|
+ if (dentry->d_inode)
|
|
+ ovl_workdir_cleanup(dir, path->mnt, dentry, level);
|
|
+ dput(dentry);
|
|
+ }
|
|
+ mutex_unlock(&dir->i_mutex);
|
|
+out:
|
|
+ ovl_cache_free(&list);
|
|
+}
|
|
+
|
|
+void ovl_workdir_cleanup(struct inode *dir, struct vfsmount *mnt,
|
|
+ struct dentry *dentry, int level)
|
|
+{
|
|
+ int err;
|
|
+
|
|
+ if (!d_is_dir(dentry) || level > 1) {
|
|
+ ovl_cleanup(dir, dentry);
|
|
+ return;
|
|
+ }
|
|
+
|
|
+ err = ovl_do_rmdir(dir, dentry);
|
|
+ if (err) {
|
|
+ struct path path = { .mnt = mnt, .dentry = dentry };
|
|
+
|
|
+ mutex_unlock(&dir->i_mutex);
|
|
+ ovl_workdir_cleanup_recurse(&path, level + 1);
|
|
+ mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
|
|
+ ovl_cleanup(dir, dentry);
|
|
+ }
|
|
+}
|
|
--- a/fs/overlayfs/super.c
|
|
+++ b/fs/overlayfs/super.c
|
|
@@ -784,7 +784,7 @@ retry:
|
|
goto out_dput;
|
|
|
|
retried = true;
|
|
- ovl_cleanup(dir, work);
|
|
+ ovl_workdir_cleanup(dir, mnt, work, 0);
|
|
dput(work);
|
|
goto retry;
|
|
}
|