1 files changed, 121 insertions, 129 deletions

diff --git a/fs/xattr.c b/fs/xattr.c
index c243905835ab..3368659c471e 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -24,6 +24,59 @@
 
 #include <asm/uaccess.h>
 
+static const char *
+strcmp_prefix(const char *a, const char *a_prefix)
+{
+	while (*a_prefix && *a == *a_prefix) {
+		a++;
+		a_prefix++;
+	}
+	return *a_prefix ? NULL : a;
+}
+
+/*
+ * In order to implement different sets of xattr operations for each xattr
+ * prefix, a filesystem should create a null-terminated array of struct
+ * xattr_handler (one for each prefix) and hang a pointer to it off of the
+ * s_xattr field of the superblock.
+ */
+#define for_each_xattr_handler(handlers, handler)		\
+	if (handlers)						\
+		for ((handler) = *(handlers)++;			\
+			(handler) != NULL;			\
+			(handler) = *(handlers)++)
+
+/*
+ * Find the xattr_handler with the matching prefix.
+ */
+static const struct xattr_handler *
+xattr_resolve_name(struct inode *inode, const char **name)
+{
+	const struct xattr_handler **handlers = inode->i_sb->s_xattr;
+	const struct xattr_handler *handler;
+
+	if (!(inode->i_opflags & IOP_XATTR)) {
+		if (unlikely(is_bad_inode(inode)))
+			return ERR_PTR(-EIO);
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+	for_each_xattr_handler(handlers, handler) {
+		const char *n;
+
+		n = strcmp_prefix(*name, xattr_prefix(handler));
+		if (n) {
+			if (!handler->prefix ^ !*n) {
+				if (*n)
+					continue;
+				return ERR_PTR(-EINVAL);
+			}
+			*name = n;
+			return handler;
+		}
+	}
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
 /*
  * Check permissions for extended attribute access.  This is a bit complicated
  * because different namespaces have very different rules.
@@ -80,6 +133,23 @@ xattr_permission(struct inode *inode, const char *name, int mask)
 	return inode_permission(inode, mask);
 }
 
+int
+__vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
+	       const void *value, size_t size, int flags)
+{
+	const struct xattr_handler *handler;
+
+	handler = xattr_resolve_name(inode, &name);
+	if (IS_ERR(handler))
+		return PTR_ERR(handler);
+	if (!handler->set)
+		return -EOPNOTSUPP;
+	if (size == 0)
+		value = "";  /* empty EA, do not remove */
+	return handler->set(handler, dentry, inode, name, value, size, flags);
+}
+EXPORT_SYMBOL(__vfs_setxattr);
+
 /**
  *  __vfs_setxattr_noperm - perform setxattr operation without performing
  *  permission checks.
@@ -106,8 +176,8 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
 
 	if (issec)
 		inode->i_flags &= ~S_NOSEC;
-	if (inode->i_op->setxattr) {
-		error = inode->i_op->setxattr(dentry, inode, name, value, size, flags);
+	if (inode->i_opflags & IOP_XATTR) {
+		error = __vfs_setxattr(dentry, inode, name, value, size, flags);
 		if (!error) {
 			fsnotify_xattr(dentry);
 			security_inode_post_setxattr(dentry, name, value,
@@ -115,6 +185,9 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
 		}
 	} else if (issec) {
 		const char *suffix = name + XATTR_SECURITY_PREFIX_LEN;
+
+		if (unlikely(is_bad_inode(inode)))
+			return -EIO;
 		error = security_inode_setsecurity(inode, suffix, value,
 						   size, flags);
 		if (!error)
@@ -188,6 +261,7 @@ ssize_t
 vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value,
 		   size_t xattr_size, gfp_t flags)
 {
+	const struct xattr_handler *handler;
 	struct inode *inode = dentry->d_inode;
 	char *value = *xattr_value;
 	int error;
@@ -196,10 +270,12 @@ vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value,
 	if (error)
 		return error;
 
-	if (!inode->i_op->getxattr)
+	handler = xattr_resolve_name(inode, &name);
+	if (IS_ERR(handler))
+		return PTR_ERR(handler);
+	if (!handler->get)
 		return -EOPNOTSUPP;
-
-	error = inode->i_op->getxattr(dentry, inode, name, NULL, 0);
+	error = handler->get(handler, dentry, inode, name, NULL, 0);
 	if (error < 0)
 		return error;
 
@@ -210,12 +286,27 @@ vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value,
 		memset(value, 0, error + 1);
 	}
 
-	error = inode->i_op->getxattr(dentry, inode, name, value, error);
+	error = handler->get(handler, dentry, inode, name, value, error);
 	*xattr_value = value;
 	return error;
 }
 
 ssize_t
+__vfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name,
+	       void *value, size_t size)
+{
+	const struct xattr_handler *handler;
+
+	handler = xattr_resolve_name(inode, &name);
+	if (IS_ERR(handler))
+		return PTR_ERR(handler);
+	if (!handler->get)
+		return -EOPNOTSUPP;
+	return handler->get(handler, dentry, inode, name, value, size);
+}
+EXPORT_SYMBOL(__vfs_getxattr);
+
+ssize_t
 vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size)
 {
 	struct inode *inode = dentry->d_inode;
@@ -242,28 +333,24 @@ vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size)
 		return ret;
 	}
 nolsm:
-	if (inode->i_op->getxattr)
-		error = inode->i_op->getxattr(dentry, inode, name, value, size);
-	else
-		error = -EOPNOTSUPP;
-
-	return error;
+	return __vfs_getxattr(dentry, inode, name, value, size);
 }
 EXPORT_SYMBOL_GPL(vfs_getxattr);
 
 ssize_t
-vfs_listxattr(struct dentry *d, char *list, size_t size)
+vfs_listxattr(struct dentry *dentry, char *list, size_t size)
 {
+	struct inode *inode = d_inode(dentry);
 	ssize_t error;
 
-	error = security_inode_listxattr(d);
+	error = security_inode_listxattr(dentry);
 	if (error)
 		return error;
-	error = -EOPNOTSUPP;
-	if (d->d_inode->i_op->listxattr) {
-		error = d->d_inode->i_op->listxattr(d, list, size);
+	if (inode->i_op->listxattr && (inode->i_opflags & IOP_XATTR)) {
+		error = -EOPNOTSUPP;
+		error = inode->i_op->listxattr(dentry, list, size);
 	} else {
-		error = security_inode_listsecurity(d->d_inode, list, size);
+		error = security_inode_listsecurity(inode, list, size);
 		if (size && error > size)
 			error = -ERANGE;
 	}
@@ -272,14 +359,26 @@ vfs_listxattr(struct dentry *d, char *list, size_t size)
 EXPORT_SYMBOL_GPL(vfs_listxattr);
 
 int
+__vfs_removexattr(struct dentry *dentry, const char *name)
+{
+	struct inode *inode = d_inode(dentry);
+	const struct xattr_handler *handler;
+
+	handler = xattr_resolve_name(inode, &name);
+	if (IS_ERR(handler))
+		return PTR_ERR(handler);
+	if (!handler->set)
+		return -EOPNOTSUPP;
+	return handler->set(handler, dentry, inode, name, NULL, 0, XATTR_REPLACE);
+}
+EXPORT_SYMBOL(__vfs_removexattr);
+
+int
 vfs_removexattr(struct dentry *dentry, const char *name)
 {
 	struct inode *inode = dentry->d_inode;
 	int error;
 
-	if (!inode->i_op->removexattr)
-		return -EOPNOTSUPP;
-
 	error = xattr_permission(inode, name, MAY_WRITE);
 	if (error)
 		return error;
@@ -289,7 +388,7 @@ vfs_removexattr(struct dentry *dentry, const char *name)
 	if (error)
 		goto out;
 
-	error = inode->i_op->removexattr(dentry, name);
+	error = __vfs_removexattr(dentry, name);
 
 	if (!error) {
 		fsnotify_xattr(dentry);
@@ -641,76 +740,6 @@ SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name)
 	return error;
 }
 
-
-static const char *
-strcmp_prefix(const char *a, const char *a_prefix)
-{
-	while (*a_prefix && *a == *a_prefix) {
-		a++;
-		a_prefix++;
-	}
-	return *a_prefix ? NULL : a;
-}
-
-/*
- * In order to implement different sets of xattr operations for each xattr
- * prefix with the generic xattr API, a filesystem should create a
- * null-terminated array of struct xattr_handler (one for each prefix) and
- * hang a pointer to it off of the s_xattr field of the superblock.
- *
- * The generic_fooxattr() functions will use this list to dispatch xattr
- * operations to the correct xattr_handler.
- */
-#define for_each_xattr_handler(handlers, handler)		\
-	if (handlers)						\
-		for ((handler) = *(handlers)++;			\
-			(handler) != NULL;			\
-			(handler) = *(handlers)++)
-
-/*
- * Find the xattr_handler with the matching prefix.
- */
-static const struct xattr_handler *
-xattr_resolve_name(const struct xattr_handler **handlers, const char **name)
-{
-	const struct xattr_handler *handler;
-
-	if (!*name)
-		return ERR_PTR(-EINVAL);
-
-	for_each_xattr_handler(handlers, handler) {
-		const char *n;
-
-		n = strcmp_prefix(*name, xattr_prefix(handler));
-		if (n) {
-			if (!handler->prefix ^ !*n) {
-				if (*n)
-					continue;
-				return ERR_PTR(-EINVAL);
-			}
-			*name = n;
-			return handler;
-		}
-	}
-	return ERR_PTR(-EOPNOTSUPP);
-}
-
-/*
- * Find the handler for the prefix and dispatch its get() operation.
- */
-ssize_t
-generic_getxattr(struct dentry *dentry, struct inode *inode,
-		 const char *name, void *buffer, size_t size)
-{
-	const struct xattr_handler *handler;
-
-	handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name);
-	if (IS_ERR(handler))
-		return PTR_ERR(handler);
-	return handler->get(handler, dentry, inode,
-			    name, buffer, size);
-}
-
 /*
  * Combine the results of the list() operation from every xattr_handler in the
  * list.
@@ -747,44 +776,7 @@ generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
 	}
 	return size;
 }
-
-/*
- * Find the handler for the prefix and dispatch its set() operation.
- */
-int
-generic_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
-		 const void *value, size_t size, int flags)
-{
-	const struct xattr_handler *handler;
-
-	if (size == 0)
-		value = "";  /* empty EA, do not remove */
-	handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name);
-	if (IS_ERR(handler))
-		return PTR_ERR(handler);
-	return handler->set(handler, dentry, inode, name, value, size, flags);
-}
-
-/*
- * Find the handler for the prefix and dispatch its set() operation to remove
- * any associated extended attribute.
- */
-int
-generic_removexattr(struct dentry *dentry, const char *name)
-{
-	const struct xattr_handler *handler;
-
-	handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name);
-	if (IS_ERR(handler))
-		return PTR_ERR(handler);
-	return handler->set(handler, dentry, d_inode(dentry), name, NULL,
-			    0, XATTR_REPLACE);
-}
-
-EXPORT_SYMBOL(generic_getxattr);
 EXPORT_SYMBOL(generic_listxattr);
-EXPORT_SYMBOL(generic_setxattr);
-EXPORT_SYMBOL(generic_removexattr);
 
 /**
  * xattr_full_name  -  Compute full attribute name from suffix