diff options
Diffstat (limited to 'fs/overlayfs/inode.c')
| -rw-r--r-- | fs/overlayfs/inode.c | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 4060ffde8722..4f729ffff75d 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -42,6 +42,19 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr) int err; struct dentry *upperdentry; + /* + * Check for permissions before trying to copy-up. This is redundant + * since it will be rechecked later by ->setattr() on upper dentry. But + * without this, copy-up can be triggered by just about anybody. + * + * We don't initialize inode->size, which just means that + * inode_newsize_ok() will always check against MAX_LFS_FILESIZE and not + * check for a swapfile (which this won't be anyway). + */ + err = inode_change_ok(dentry->d_inode, attr); + if (err) + return err; + err = ovl_want_write(dentry); if (err) goto out; @@ -50,8 +63,13 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr) if (!err) { upperdentry = ovl_dentry_upper(dentry); + if (attr->ia_valid & (ATTR_KILL_SUID|ATTR_KILL_SGID)) + attr->ia_valid &= ~ATTR_MODE; + mutex_lock(&upperdentry->d_inode->i_mutex); err = notify_change(upperdentry, attr, NULL); + if (!err) + ovl_copyattr(upperdentry->d_inode, dentry->d_inode); mutex_unlock(&upperdentry->d_inode->i_mutex); } ovl_drop_write(dentry); @@ -397,12 +415,11 @@ struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, if (!inode) return NULL; - mode &= S_IFMT; - inode->i_ino = get_next_ino(); inode->i_mode = mode; inode->i_flags |= S_NOATIME | S_NOCMTIME; + mode &= S_IFMT; switch (mode) { case S_IFDIR: inode->i_private = oe; |