diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-05-27 09:47:57 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-05-27 09:47:57 -0700 |
commit | 3cfd4ba7d37b52eb965ed05209647072932dfd0a (patch) | |
tree | 099660db38046f017104820623e4431dd126b757 | |
parent | 1b887bf31dd6e2f8cef80d205d6e9949a7dd98cc (diff) | |
parent | cc6f67bcafcb6bbbb2d1be1603dcd95125a52800 (diff) |
Merge branch 'overlayfs-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull two overlayfs fixes from Miklos Szeredi:
"Overlayfs rmdir() failed to check for emptiness in one case; this was
introduced in 4.0. The other bug was there since day one: failure to
mount if upper fs is full, which bit some OpenWRT folks"
* 'overlayfs-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: mount read-only if workdir can't be created
ovl: don't remove non-empty opaque directory
-rw-r--r-- | fs/overlayfs/copy_up.c | 3 | ||||
-rw-r--r-- | fs/overlayfs/dir.c | 33 | ||||
-rw-r--r-- | fs/overlayfs/super.c | 10 |
3 files changed, 36 insertions, 10 deletions
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 24f640441bd9..84d693d37428 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -299,6 +299,9 @@ int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, struct cred *override_cred; char *link = NULL; + if (WARN_ON(!workdir)) + return -EROFS; + ovl_path_upper(parent, &parentpath); upperdir = parentpath.dentry; diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index d139405d2bfa..692ceda3bc21 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -222,6 +222,9 @@ static struct dentry *ovl_clear_empty(struct dentry *dentry, struct kstat stat; int err; + if (WARN_ON(!workdir)) + return ERR_PTR(-EROFS); + err = ovl_lock_rename_workdir(workdir, upperdir); if (err) goto out; @@ -322,6 +325,9 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode, struct dentry *newdentry; int err; + if (WARN_ON(!workdir)) + return -EROFS; + err = ovl_lock_rename_workdir(workdir, upperdir); if (err) goto out; @@ -506,11 +512,28 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir) struct dentry *opaquedir = NULL; int err; - if (is_dir && OVL_TYPE_MERGE_OR_LOWER(ovl_path_type(dentry))) { - opaquedir = ovl_check_empty_and_clear(dentry); - err = PTR_ERR(opaquedir); - if (IS_ERR(opaquedir)) - goto out; + if (WARN_ON(!workdir)) + return -EROFS; + + if (is_dir) { + if (OVL_TYPE_MERGE_OR_LOWER(ovl_path_type(dentry))) { + opaquedir = ovl_check_empty_and_clear(dentry); + err = PTR_ERR(opaquedir); + if (IS_ERR(opaquedir)) + goto out; + } else { + LIST_HEAD(list); + + /* + * When removing an empty opaque directory, then it + * makes no sense to replace it with an exact replica of + * itself. But emptiness still needs to be checked. + */ + err = ovl_check_empty_dir(dentry, &list); + ovl_cache_free(&list); + if (err) + goto out; + } } err = ovl_lock_rename_workdir(workdir, upperdir); diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 5f0d1993e6e3..bf8537c7f455 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -529,7 +529,7 @@ static int ovl_remount(struct super_block *sb, int *flags, char *data) { struct ovl_fs *ufs = sb->s_fs_info; - if (!(*flags & MS_RDONLY) && !ufs->upper_mnt) + if (!(*flags & MS_RDONLY) && (!ufs->upper_mnt || !ufs->workdir)) return -EROFS; return 0; @@ -925,9 +925,10 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) ufs->workdir = ovl_workdir_create(ufs->upper_mnt, workpath.dentry); err = PTR_ERR(ufs->workdir); if (IS_ERR(ufs->workdir)) { - pr_err("overlayfs: failed to create directory %s/%s\n", - ufs->config.workdir, OVL_WORKDIR_NAME); - goto out_put_upper_mnt; + pr_warn("overlayfs: failed to create directory %s/%s (errno: %i); mounting read-only\n", + ufs->config.workdir, OVL_WORKDIR_NAME, -err); + sb->s_flags |= MS_RDONLY; + ufs->workdir = NULL; } } @@ -997,7 +998,6 @@ out_put_lower_mnt: kfree(ufs->lower_mnt); out_put_workdir: dput(ufs->workdir); -out_put_upper_mnt: mntput(ufs->upper_mnt); out_put_lowerpath: for (i = 0; i < numlower; i++) |