diff options
Diffstat (limited to 'fs/overlayfs/super.c')
| -rw-r--r-- | fs/overlayfs/super.c | 61 |
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) { |