Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
"Assorted fixes, most in overlayfs land"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ovl: ovl_dir_fsync() cleanup
ovl: update MAINTAINERS
ovl: pass dentry into ovl_dir_read_merged()
ovl: use lockless_dereference() for upperdentry
ovl: allow filenames with comma
ovl: fix race in private xattr checks
ovl: fix remove/copy-up race
ovl: rename filesystem type to "overlay"
isofs: avoid unused function warning
vfs: fix reference leak in d_prune_aliases()
diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt
index 530850a..a27c950 100644
--- a/Documentation/filesystems/overlayfs.txt
+++ b/Documentation/filesystems/overlayfs.txt
@@ -64,7 +64,7 @@
At mount time, the two directories given as mount options "lowerdir" and
"upperdir" are combined into a merged directory:
- mount -t overlayfs overlayfs -olowerdir=/lower,upperdir=/upper,\
+ mount -t overlay overlay -olowerdir=/lower,upperdir=/upper,\
workdir=/work /merged
The "workdir" needs to be an empty directory on the same filesystem
diff --git a/MAINTAINERS b/MAINTAINERS
index c444907..0ff630d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6888,11 +6888,12 @@
F: include/scsi/osd_*
F: fs/exofs/
-OVERLAYFS FILESYSTEM
+OVERLAY FILESYSTEM
M: Miklos Szeredi <miklos@szeredi.hu>
-L: linux-fsdevel@vger.kernel.org
+L: linux-unionfs@vger.kernel.org
+T: git git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs.git
S: Supported
-F: fs/overlayfs/*
+F: fs/overlayfs/
F: Documentation/filesystems/overlayfs.txt
P54 WIRELESS DRIVER
diff --git a/fs/Makefile b/fs/Makefile
index 34a1b9de..da0bbb4 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -104,7 +104,7 @@
obj-$(CONFIG_AUTOFS4_FS) += autofs4/
obj-$(CONFIG_ADFS_FS) += adfs/
obj-$(CONFIG_FUSE_FS) += fuse/
-obj-$(CONFIG_OVERLAYFS_FS) += overlayfs/
+obj-$(CONFIG_OVERLAY_FS) += overlayfs/
obj-$(CONFIG_UDF_FS) += udf/
obj-$(CONFIG_SUN_OPENPROMFS) += openpromfs/
obj-$(CONFIG_OMFS_FS) += omfs/
diff --git a/fs/dcache.c b/fs/dcache.c
index 3ffef7f..5bc72b0 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -778,6 +778,7 @@
struct dentry *parent = lock_parent(dentry);
if (likely(!dentry->d_lockref.count)) {
__dentry_kill(dentry);
+ dput(parent);
goto restart;
}
if (parent)
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index fe839b9..d67a16f 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -174,27 +174,6 @@
* Compute the hash for the isofs name corresponding to the dentry.
*/
static int
-isofs_hash_common(struct qstr *qstr, int ms)
-{
- const char *name;
- int len;
-
- len = qstr->len;
- name = qstr->name;
- if (ms) {
- while (len && name[len-1] == '.')
- len--;
- }
-
- qstr->hash = full_name_hash(name, len);
-
- return 0;
-}
-
-/*
- * Compute the hash for the isofs name corresponding to the dentry.
- */
-static int
isofs_hashi_common(struct qstr *qstr, int ms)
{
const char *name;
@@ -263,6 +242,27 @@
}
#ifdef CONFIG_JOLIET
+/*
+ * Compute the hash for the isofs name corresponding to the dentry.
+ */
+static int
+isofs_hash_common(struct qstr *qstr, int ms)
+{
+ const char *name;
+ int len;
+
+ len = qstr->len;
+ name = qstr->name;
+ if (ms) {
+ while (len && name[len-1] == '.')
+ len--;
+ }
+
+ qstr->hash = full_name_hash(name, len);
+
+ return 0;
+}
+
static int
isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
{
diff --git a/fs/overlayfs/Kconfig b/fs/overlayfs/Kconfig
index e601259..3435581 100644
--- a/fs/overlayfs/Kconfig
+++ b/fs/overlayfs/Kconfig
@@ -1,4 +1,4 @@
-config OVERLAYFS_FS
+config OVERLAY_FS
tristate "Overlay filesystem support"
help
An overlay filesystem combines two filesystems - an 'upper' filesystem
diff --git a/fs/overlayfs/Makefile b/fs/overlayfs/Makefile
index 8f91889..900daed 100644
--- a/fs/overlayfs/Makefile
+++ b/fs/overlayfs/Makefile
@@ -2,6 +2,6 @@
# Makefile for the overlay filesystem.
#
-obj-$(CONFIG_OVERLAYFS_FS) += overlayfs.o
+obj-$(CONFIG_OVERLAY_FS) += overlay.o
-overlayfs-objs := super.o inode.o dir.o readdir.o copy_up.o
+overlay-objs := super.o inode.o dir.o readdir.o copy_up.o
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 15cd91a..8ffc4b9 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -284,8 +284,7 @@
return ERR_PTR(err);
}
-static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry,
- enum ovl_path_type type)
+static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry)
{
int err;
struct dentry *ret = NULL;
@@ -294,8 +293,17 @@
err = ovl_check_empty_dir(dentry, &list);
if (err)
ret = ERR_PTR(err);
- else if (type == OVL_PATH_MERGE)
- ret = ovl_clear_empty(dentry, &list);
+ else {
+ /*
+ * If no upperdentry then skip clearing whiteouts.
+ *
+ * Can race with copy-up, since we don't hold the upperdir
+ * mutex. Doesn't matter, since copy-up can't create a
+ * non-empty directory from an empty one.
+ */
+ if (ovl_dentry_upper(dentry))
+ ret = ovl_clear_empty(dentry, &list);
+ }
ovl_cache_free(&list);
@@ -487,8 +495,7 @@
return err;
}
-static int ovl_remove_and_whiteout(struct dentry *dentry,
- enum ovl_path_type type, bool is_dir)
+static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir)
{
struct dentry *workdir = ovl_workdir(dentry);
struct inode *wdir = workdir->d_inode;
@@ -500,7 +507,7 @@
int err;
if (is_dir) {
- opaquedir = ovl_check_empty_and_clear(dentry, type);
+ opaquedir = ovl_check_empty_and_clear(dentry);
err = PTR_ERR(opaquedir);
if (IS_ERR(opaquedir))
goto out;
@@ -515,9 +522,10 @@
if (IS_ERR(whiteout))
goto out_unlock;
- if (type == OVL_PATH_LOWER) {
+ upper = ovl_dentry_upper(dentry);
+ if (!upper) {
upper = lookup_one_len(dentry->d_name.name, upperdir,
- dentry->d_name.len);
+ dentry->d_name.len);
err = PTR_ERR(upper);
if (IS_ERR(upper))
goto kill_whiteout;
@@ -529,7 +537,6 @@
} else {
int flags = 0;
- upper = ovl_dentry_upper(dentry);
if (opaquedir)
upper = opaquedir;
err = -ESTALE;
@@ -648,7 +655,7 @@
cap_raise(override_cred->cap_effective, CAP_CHOWN);
old_cred = override_creds(override_cred);
- err = ovl_remove_and_whiteout(dentry, type, is_dir);
+ err = ovl_remove_and_whiteout(dentry, is_dir);
revert_creds(old_cred);
put_cred(override_cred);
@@ -781,7 +788,7 @@
}
if (overwrite && (new_type == OVL_PATH_LOWER || new_type == OVL_PATH_MERGE) && new_is_dir) {
- opaquedir = ovl_check_empty_and_clear(new, new_type);
+ opaquedir = ovl_check_empty_and_clear(new);
err = PTR_ERR(opaquedir);
if (IS_ERR(opaquedir)) {
opaquedir = NULL;
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index af2d18c..07d74b2 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -235,26 +235,36 @@
return err;
}
+static bool ovl_need_xattr_filter(struct dentry *dentry,
+ enum ovl_path_type type)
+{
+ return type == OVL_PATH_UPPER && S_ISDIR(dentry->d_inode->i_mode);
+}
+
ssize_t ovl_getxattr(struct dentry *dentry, const char *name,
void *value, size_t size)
{
- if (ovl_path_type(dentry->d_parent) == OVL_PATH_MERGE &&
- ovl_is_private_xattr(name))
+ struct path realpath;
+ enum ovl_path_type type = ovl_path_real(dentry, &realpath);
+
+ if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name))
return -ENODATA;
- return vfs_getxattr(ovl_dentry_real(dentry), name, value, size);
+ return vfs_getxattr(realpath.dentry, name, value, size);
}
ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)
{
+ struct path realpath;
+ enum ovl_path_type type = ovl_path_real(dentry, &realpath);
ssize_t res;
int off;
- res = vfs_listxattr(ovl_dentry_real(dentry), list, size);
+ res = vfs_listxattr(realpath.dentry, list, size);
if (res <= 0 || size == 0)
return res;
- if (ovl_path_type(dentry->d_parent) != OVL_PATH_MERGE)
+ if (!ovl_need_xattr_filter(dentry, type))
return res;
/* filter out private xattrs */
@@ -279,17 +289,16 @@
{
int err;
struct path realpath;
- enum ovl_path_type type;
+ enum ovl_path_type type = ovl_path_real(dentry, &realpath);
err = ovl_want_write(dentry);
if (err)
goto out;
- if (ovl_path_type(dentry->d_parent) == OVL_PATH_MERGE &&
- ovl_is_private_xattr(name))
+ err = -ENODATA;
+ if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name))
goto out_drop_write;
- type = ovl_path_real(dentry, &realpath);
if (type == OVL_PATH_LOWER) {
err = vfs_getxattr(realpath.dentry, name, NULL, 0);
if (err < 0)
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 2a7ef4f..ab1e3dc 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -274,11 +274,11 @@
return 0;
}
-static inline int ovl_dir_read_merged(struct path *upperpath,
- struct path *lowerpath,
- struct list_head *list)
+static int ovl_dir_read_merged(struct dentry *dentry, struct list_head *list)
{
int err;
+ struct path lowerpath;
+ struct path upperpath;
struct ovl_readdir_data rdd = {
.ctx.actor = ovl_fill_merge,
.list = list,
@@ -286,25 +286,28 @@
.is_merge = false,
};
- if (upperpath->dentry) {
- err = ovl_dir_read(upperpath, &rdd);
+ ovl_path_lower(dentry, &lowerpath);
+ ovl_path_upper(dentry, &upperpath);
+
+ if (upperpath.dentry) {
+ err = ovl_dir_read(&upperpath, &rdd);
if (err)
goto out;
- if (lowerpath->dentry) {
- err = ovl_dir_mark_whiteouts(upperpath->dentry, &rdd);
+ if (lowerpath.dentry) {
+ err = ovl_dir_mark_whiteouts(upperpath.dentry, &rdd);
if (err)
goto out;
}
}
- if (lowerpath->dentry) {
+ if (lowerpath.dentry) {
/*
* Insert lowerpath entries before upperpath ones, this allows
* offsets to be reasonably constant
*/
list_add(&rdd.middle, rdd.list);
rdd.is_merge = true;
- err = ovl_dir_read(lowerpath, &rdd);
+ err = ovl_dir_read(&lowerpath, &rdd);
list_del(&rdd.middle);
}
out:
@@ -329,8 +332,6 @@
static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry)
{
int res;
- struct path lowerpath;
- struct path upperpath;
struct ovl_dir_cache *cache;
cache = ovl_dir_cache(dentry);
@@ -347,10 +348,7 @@
cache->refcount = 1;
INIT_LIST_HEAD(&cache->entries);
- ovl_path_lower(dentry, &lowerpath);
- ovl_path_upper(dentry, &upperpath);
-
- res = ovl_dir_read_merged(&upperpath, &lowerpath, &cache->entries);
+ res = ovl_dir_read_merged(dentry, &cache->entries);
if (res) {
ovl_cache_free(&cache->entries);
kfree(cache);
@@ -452,10 +450,10 @@
/*
* Need to check if we started out being a lower dir, but got copied up
*/
- if (!od->is_upper && ovl_path_type(dentry) == OVL_PATH_MERGE) {
+ if (!od->is_upper && ovl_path_type(dentry) != OVL_PATH_LOWER) {
struct inode *inode = file_inode(file);
- realfile =lockless_dereference(od->upperfile);
+ realfile = lockless_dereference(od->upperfile);
if (!realfile) {
struct path upperpath;
@@ -538,14 +536,9 @@
int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list)
{
int err;
- struct path lowerpath;
- struct path upperpath;
struct ovl_cache_entry *p;
- ovl_path_upper(dentry, &upperpath);
- ovl_path_lower(dentry, &lowerpath);
-
- err = ovl_dir_read_merged(&upperpath, &lowerpath, list);
+ err = ovl_dir_read_merged(dentry, list);
if (err)
return err;
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 08b704c..f16d318b 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -24,7 +24,7 @@
MODULE_DESCRIPTION("Overlay filesystem");
MODULE_LICENSE("GPL");
-#define OVERLAYFS_SUPER_MAGIC 0x794c764f
+#define OVERLAYFS_SUPER_MAGIC 0x794c7630
struct ovl_config {
char *lowerdir;
@@ -84,12 +84,7 @@
static struct dentry *ovl_upperdentry_dereference(struct ovl_entry *oe)
{
- struct dentry *upperdentry = ACCESS_ONCE(oe->__upperdentry);
- /*
- * Make sure to order reads to upperdentry wrt ovl_dentry_update()
- */
- smp_read_barrier_depends();
- return upperdentry;
+ return lockless_dereference(oe->__upperdentry);
}
void ovl_path_upper(struct dentry *dentry, struct path *path)
@@ -462,11 +457,34 @@
{OPT_ERR, NULL}
};
+static char *ovl_next_opt(char **s)
+{
+ char *sbegin = *s;
+ char *p;
+
+ if (sbegin == NULL)
+ return NULL;
+
+ for (p = sbegin; *p; p++) {
+ if (*p == '\\') {
+ p++;
+ if (!*p)
+ break;
+ } else if (*p == ',') {
+ *p = '\0';
+ *s = p + 1;
+ return sbegin;
+ }
+ }
+ *s = NULL;
+ return sbegin;
+}
+
static int ovl_parse_opt(char *opt, struct ovl_config *config)
{
char *p;
- while ((p = strsep(&opt, ",")) != NULL) {
+ while ((p = ovl_next_opt(&opt)) != NULL) {
int token;
substring_t args[MAX_OPT_ARGS];
@@ -554,15 +572,34 @@
goto out_unlock;
}
+static void ovl_unescape(char *s)
+{
+ char *d = s;
+
+ for (;; s++, d++) {
+ if (*s == '\\')
+ s++;
+ *d = *s;
+ if (!*s)
+ break;
+ }
+}
+
static int ovl_mount_dir(const char *name, struct path *path)
{
int err;
+ char *tmp = kstrdup(name, GFP_KERNEL);
- err = kern_path(name, LOOKUP_FOLLOW, path);
+ if (!tmp)
+ return -ENOMEM;
+
+ ovl_unescape(tmp);
+ err = kern_path(tmp, LOOKUP_FOLLOW, path);
if (err) {
- pr_err("overlayfs: failed to resolve '%s': %i\n", name, err);
+ pr_err("overlayfs: failed to resolve '%s': %i\n", tmp, err);
err = -EINVAL;
}
+ kfree(tmp);
return err;
}
@@ -776,11 +813,11 @@
static struct file_system_type ovl_fs_type = {
.owner = THIS_MODULE,
- .name = "overlayfs",
+ .name = "overlay",
.mount = ovl_mount,
.kill_sb = kill_anon_super,
};
-MODULE_ALIAS_FS("overlayfs");
+MODULE_ALIAS_FS("overlay");
static int __init ovl_init(void)
{
