Merge tag 'upstream-4.13-rc1' of git://git.infradead.org/linux-ubifs

Pull UBIFS updates from Richard Weinberger:

 - Updates and fixes for the file encryption mode

 - Minor improvements

 - Random fixes

* tag 'upstream-4.13-rc1' of git://git.infradead.org/linux-ubifs:
  ubifs: Set double hash cookie also for RENAME_EXCHANGE
  ubifs: Massage assert in ubifs_xattr_set() wrt. init_xattrs
  ubifs: Don't leak kernel memory to the MTD
  ubifs: Change gfp flags in page allocation for bulk read
  ubifs: Fix oops when remounting with no_bulk_read.
  ubifs: Fail commit if TNC is obviously inconsistent
  ubifs: allow userspace to map mounts to volumes
  ubifs: Wire-up statx() support
  ubifs: Remove dead code from ubifs_get_link()
  ubifs: Massage debug prints wrt. fscrypt
  ubifs: Add assert to dent_key_init()
  ubifs: Fix unlink code wrt. double hash lookups
  ubifs: Fix data node size for truncating uncompressed nodes
  ubifs: Don't encrypt special files on creation
  ubifs: Fix memory leak in RENAME_WHITEOUT error path in do_rename
  ubifs: Fix inode data budget in ubifs_mknod
  ubifs: Correctly evict xattr inodes
  ubifs: Unexport ubifs_inode_slab
  ubifs: don't bother checking for encryption key in ->mmap()
  ubifs: require key for truncate(2) of encrypted file

1 files changed, 30 insertions, 9 deletions

diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index 6c9e62c2ef55..c13eae819cbc 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -280,7 +280,7 @@ static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum)
 }
 
 int ubifs_xattr_set(struct inode *host, const char *name, const void *value,
-		    size_t size, int flags)
+		    size_t size, int flags, bool check_lock)
 {
 	struct inode *inode;
 	struct ubifs_info *c = host->i_sb->s_fs_info;
@@ -289,12 +289,7 @@ int ubifs_xattr_set(struct inode *host, const char *name, const void *value,
 	union ubifs_key key;
 	int err;
 
-	/*
-	 * Creating an encryption context is done unlocked since we
-	 * operate on a new inode which is not visible to other users
-	 * at this point.
-	 */
-	if (strcmp(name, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT) != 0)
+	if (check_lock)
 		ubifs_assert(inode_is_locked(host));
 
 	if (size > UBIFS_MAX_INO_DATA)
@@ -513,6 +508,28 @@ out_cancel:
 	return err;
 }
 
+/**
+ * ubifs_evict_xattr_inode - Evict an xattr inode.
+ * @c: UBIFS file-system description object
+ * @xattr_inum: xattr inode number
+ *
+ * When an inode that hosts xattrs is being removed we have to make sure
+ * that cached inodes of the xattrs also get removed from the inode cache
+ * otherwise we'd waste memory. This function looks up an inode from the
+ * inode cache and clears the link counter such that iput() will evict
+ * the inode.
+ */
+void ubifs_evict_xattr_inode(struct ubifs_info *c, ino_t xattr_inum)
+{
+	struct inode *inode;
+
+	inode = ilookup(c->vfs_sb, xattr_inum);
+	if (inode) {
+		clear_nlink(inode);
+		iput(inode);
+	}
+}
+
 static int ubifs_xattr_remove(struct inode *host, const char *name)
 {
 	struct inode *inode;
@@ -576,8 +593,12 @@ static int init_xattrs(struct inode *inode, const struct xattr *xattr_array,
 		}
 		strcpy(name, XATTR_SECURITY_PREFIX);
 		strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
+		/*
+		 * creating a new inode without holding the inode rwsem,
+		 * no need to check whether inode is locked.
+		 */
 		err = ubifs_xattr_set(inode, name, xattr->value,
-				      xattr->value_len, 0);
+				      xattr->value_len, 0, false);
 		kfree(name);
 		if (err < 0)
 			break;
@@ -624,7 +645,7 @@ static int xattr_set(const struct xattr_handler *handler,
 	name = xattr_full_name(handler, name);
 
 	if (value)
-		return ubifs_xattr_set(inode, name, value, size, flags);
+		return ubifs_xattr_set(inode, name, value, size, flags, true);
 	else
 		return ubifs_xattr_remove(inode, name);
 }