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Diffstat (limited to 'fs/overlayfs/super.c')
-rw-r--r--fs/overlayfs/super.c61
1 files changed, 49 insertions, 12 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 08b704cebfc4..f16d318b71f8 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -24,7 +24,7 @@ MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
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 @@ enum ovl_path_type ovl_path_type(struct dentry *dentry)
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 @@ static const match_table_t ovl_tokens = {
{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 @@ out_dput:
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);
+
+ if (!tmp)
+ return -ENOMEM;
- err = kern_path(name, LOOKUP_FOLLOW, path);
+ 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 dentry *ovl_mount(struct file_system_type *fs_type, int flags,
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)
{