1 files changed, 43 insertions, 7 deletions

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index de7f9168a118..345fc89c4286 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -91,6 +91,30 @@ struct workqueue_struct	*cifsiod_wq;
 __u8 cifs_client_guid[SMB2_CLIENT_GUID_SIZE];
 #endif
 
+/*
+ * Bumps refcount for cifs super block.
+ * Note that it should be only called if a referece to VFS super block is
+ * already held, e.g. in open-type syscalls context. Otherwise it can race with
+ * atomic_dec_and_test in deactivate_locked_super.
+ */
+void
+cifs_sb_active(struct super_block *sb)
+{
+	struct cifs_sb_info *server = CIFS_SB(sb);
+
+	if (atomic_inc_return(&server->active) == 1)
+		atomic_inc(&sb->s_active);
+}
+
+void
+cifs_sb_deactive(struct super_block *sb)
+{
+	struct cifs_sb_info *server = CIFS_SB(sb);
+
+	if (atomic_dec_and_test(&server->active))
+		deactivate_super(sb);
+}
+
 static int
 cifs_read_super(struct super_block *sb)
 {
@@ -375,13 +399,15 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
 				   (int)(srcaddr->sa_family));
 	}
 
-	seq_printf(s, ",uid=%u", cifs_sb->mnt_uid);
+	seq_printf(s, ",uid=%u",
+		   from_kuid_munged(&init_user_ns, cifs_sb->mnt_uid));
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID)
 		seq_printf(s, ",forceuid");
 	else
 		seq_printf(s, ",noforceuid");
 
-	seq_printf(s, ",gid=%u", cifs_sb->mnt_gid);
+	seq_printf(s, ",gid=%u",
+		   from_kgid_munged(&init_user_ns, cifs_sb->mnt_gid));
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)
 		seq_printf(s, ",forcegid");
 	else
@@ -436,9 +462,13 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM)
 		seq_printf(s, ",noperm");
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID)
-		seq_printf(s, ",backupuid=%u", cifs_sb->mnt_backupuid);
+		seq_printf(s, ",backupuid=%u",
+			   from_kuid_munged(&init_user_ns,
+					    cifs_sb->mnt_backupuid));
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID)
-		seq_printf(s, ",backupgid=%u", cifs_sb->mnt_backupgid);
+		seq_printf(s, ",backupgid=%u",
+			   from_kgid_munged(&init_user_ns,
+					    cifs_sb->mnt_backupgid));
 
 	seq_printf(s, ",rsize=%u", cifs_sb->rsize);
 	seq_printf(s, ",wsize=%u", cifs_sb->wsize);
@@ -558,6 +588,11 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
 			dentry = ERR_PTR(-ENOENT);
 			break;
 		}
+		if (!S_ISDIR(dir->i_mode)) {
+			dput(dentry);
+			dentry = ERR_PTR(-ENOTDIR);
+			break;
+		}
 
 		/* skip separators */
 		while (*s == sep)
@@ -677,7 +712,7 @@ out_nls:
 static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 				   unsigned long nr_segs, loff_t pos)
 {
-	struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(iocb->ki_filp);
 	ssize_t written;
 	int rc;
 
@@ -701,7 +736,7 @@ static loff_t cifs_llseek(struct file *file, loff_t offset, int whence)
 	 */
 	if (whence != SEEK_SET && whence != SEEK_CUR) {
 		int rc;
-		struct inode *inode = file->f_path.dentry->d_inode;
+		struct inode *inode = file_inode(file);
 
 		/*
 		 * We need to be sure that all dirty pages are written and the
@@ -733,7 +768,7 @@ static int cifs_setlease(struct file *file, long arg, struct file_lock **lease)
 {
 	/* note that this is called by vfs setlease with lock_flocks held
 	   to protect *lease from going away */
-	struct inode *inode = file->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct cifsFileInfo *cfile = file->private_data;
 
 	if (!(S_ISREG(inode->i_mode)))
@@ -766,6 +801,7 @@ struct file_system_type cifs_fs_type = {
 	.kill_sb = cifs_kill_sb,
 	/*  .fs_flags */
 };
+MODULE_ALIAS_FS("cifs");
 const struct inode_operations cifs_dir_inode_ops = {
 	.create = cifs_create,
 	.atomic_open = cifs_atomic_open,