X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=fs%2Fxattr.c;h=d5dd6c8b82a712085c105ec1c30f827c639ff614;hb=0e41e277971799bad2764ad4e6284817e9a6da5b;hp=58bdabcc9d3566b34ca8cc5f98bf577206001892;hpb=80602324d5a02fea97ed1328ba04e5d7f10aaff8;p=cascardo%2Flinux.git

diff --git a/fs/xattr.c b/fs/xattr.c
index 58bdabcc9d35..d5dd6c8b82a7 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -305,7 +305,6 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
 {
 	int error;
 	void *kvalue = NULL;
-	void *vvalue = NULL;	/* If non-NULL, we used vmalloc() */
 	char kname[XATTR_NAME_MAX + 1];
 
 	if (flags & ~(XATTR_CREATE|XATTR_REPLACE))
@@ -322,10 +321,9 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
 			return -E2BIG;
 		kvalue = kmalloc(size, GFP_KERNEL | __GFP_NOWARN);
 		if (!kvalue) {
-			vvalue = vmalloc(size);
-			if (!vvalue)
+			kvalue = vmalloc(size);
+			if (!kvalue)
 				return -ENOMEM;
-			kvalue = vvalue;
 		}
 		if (copy_from_user(kvalue, value, size)) {
 			error = -EFAULT;
@@ -338,10 +336,8 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
 
 	error = vfs_setxattr(d, kname, kvalue, size, flags);
 out:
-	if (vvalue)
-		vfree(vvalue);
-	else
-		kfree(kvalue);
+	kvfree(kvalue);
+
 	return error;
 }
 
@@ -409,7 +405,6 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 {
 	ssize_t error;
 	void *kvalue = NULL;
-	void *vvalue = NULL;
 	char kname[XATTR_NAME_MAX + 1];
 
 	error = strncpy_from_user(kname, name, sizeof(kname));
@@ -423,10 +418,9 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 			size = XATTR_SIZE_MAX;
 		kvalue = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
 		if (!kvalue) {
-			vvalue = vmalloc(size);
-			if (!vvalue)
+			kvalue = vmalloc(size);
+			if (!kvalue)
 				return -ENOMEM;
-			kvalue = vvalue;
 		}
 	}
 
@@ -442,10 +436,9 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 		   than XATTR_SIZE_MAX bytes. Not possible. */
 		error = -E2BIG;
 	}
-	if (vvalue)
-		vfree(vvalue);
-	else
-		kfree(kvalue);
+
+	kvfree(kvalue);
+
 	return error;
 }
 
@@ -502,17 +495,15 @@ listxattr(struct dentry *d, char __user *list, size_t size)
 {
 	ssize_t error;
 	char *klist = NULL;
-	char *vlist = NULL;	/* If non-NULL, we used vmalloc() */
 
 	if (size) {
 		if (size > XATTR_LIST_MAX)
 			size = XATTR_LIST_MAX;
 		klist = kmalloc(size, __GFP_NOWARN | GFP_KERNEL);
 		if (!klist) {
-			vlist = vmalloc(size);
-			if (!vlist)
+			klist = vmalloc(size);
+			if (!klist)
 				return -ENOMEM;
-			klist = vlist;
 		}
 	}
 
@@ -525,10 +516,9 @@ listxattr(struct dentry *d, char __user *list, size_t size)
 		   than XATTR_LIST_MAX bytes. Not possible. */
 		error = -E2BIG;
 	}
-	if (vlist)
-		vfree(vlist);
-	else
-		kfree(klist);
+
+	kvfree(klist);
+
 	return error;
 }
 
@@ -681,13 +671,20 @@ xattr_resolve_name(const struct xattr_handler **handlers, const char **name)
 		return NULL;
 
 	for_each_xattr_handler(handlers, handler) {
-		const char *n = strcmp_prefix(*name, handler->prefix);
+		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;
-			break;
+			return handler;
 		}
 	}
-	return handler;
+	return ERR_PTR(-EOPNOTSUPP);
 }
 
 /*
@@ -699,8 +696,8 @@ generic_getxattr(struct dentry *dentry, const char *name, void *buffer, size_t s
 	const struct xattr_handler *handler;
 
 	handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name);
-	if (!handler)
-		return -EOPNOTSUPP;
+	if (IS_ERR(handler))
+		return PTR_ERR(handler);
 	return handler->get(handler, dentry, name, buffer, size);
 }
 
@@ -716,19 +713,25 @@ generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
 
 	if (!buffer) {
 		for_each_xattr_handler(handlers, handler) {
-			size += handler->list(handler, dentry, NULL, 0,
-					      NULL, 0);
+			if (!handler->name ||
+			    (handler->list && !handler->list(dentry)))
+				continue;
+			size += strlen(handler->name) + 1;
 		}
 	} else {
 		char *buf = buffer;
+		size_t len;
 
 		for_each_xattr_handler(handlers, handler) {
-			size = handler->list(handler, dentry, buf, buffer_size,
-					     NULL, 0);
-			if (size > buffer_size)
+			if (!handler->name ||
+			    (handler->list && !handler->list(dentry)))
+				continue;
+			len = strlen(handler->name);
+			if (len + 1 > buffer_size)
 				return -ERANGE;
-			buf += size;
-			buffer_size -= size;
+			memcpy(buf, handler->name, len + 1);
+			buf += len + 1;
+			buffer_size -= len + 1;
 		}
 		size = buf - buffer;
 	}
@@ -746,8 +749,8 @@ generic_setxattr(struct dentry *dentry, const char *name, const void *value, siz
 	if (size == 0)
 		value = "";  /* empty EA, do not remove */
 	handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name);
-	if (!handler)
-		return -EOPNOTSUPP;
+	if (IS_ERR(handler))
+		return PTR_ERR(handler);
 	return handler->set(handler, dentry, name, value, size, flags);
 }
 
@@ -761,8 +764,8 @@ generic_removexattr(struct dentry *dentry, const char *name)
 	const struct xattr_handler *handler;
 
 	handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name);
-	if (!handler)
-		return -EOPNOTSUPP;
+	if (IS_ERR(handler))
+		return PTR_ERR(handler);
 	return handler->set(handler, dentry, name, NULL, 0, XATTR_REPLACE);
 }
 
@@ -789,7 +792,7 @@ EXPORT_SYMBOL(generic_removexattr);
 const char *xattr_full_name(const struct xattr_handler *handler,
 			    const char *name)
 {
-	size_t prefix_len = strlen(handler->prefix);
+	size_t prefix_len = strlen(xattr_prefix(handler));
 
 	return name - prefix_len;
 }
@@ -844,8 +847,22 @@ int simple_xattr_get(struct simple_xattrs *xattrs, const char *name,
 	return ret;
 }
 
-static int __simple_xattr_set(struct simple_xattrs *xattrs, const char *name,
-			      const void *value, size_t size, int flags)
+/**
+ * simple_xattr_set - xattr SET operation for in-memory/pseudo filesystems
+ * @xattrs: target simple_xattr list
+ * @name: name of the extended attribute
+ * @value: value of the xattr. If %NULL, will remove the attribute.
+ * @size: size of the new xattr
+ * @flags: %XATTR_{CREATE|REPLACE}
+ *
+ * %XATTR_CREATE is set, the xattr shouldn't exist already; otherwise fails
+ * with -EEXIST.  If %XATTR_REPLACE is set, the xattr should exist;
+ * otherwise, fails with -ENODATA.
+ *
+ * Returns 0 on success, -errno on failure.
+ */
+int simple_xattr_set(struct simple_xattrs *xattrs, const char *name,
+		     const void *value, size_t size, int flags)
 {
 	struct simple_xattr *xattr;
 	struct simple_xattr *new_xattr = NULL;
@@ -895,73 +912,64 @@ out:
 
 }
 
-/**
- * simple_xattr_set - xattr SET operation for in-memory/pseudo filesystems
- * @xattrs: target simple_xattr list
- * @name: name of the new extended attribute
- * @value: value of the new xattr. If %NULL, will remove the attribute
- * @size: size of the new xattr
- * @flags: %XATTR_{CREATE|REPLACE}
- *
- * %XATTR_CREATE is set, the xattr shouldn't exist already; otherwise fails
- * with -EEXIST.  If %XATTR_REPLACE is set, the xattr should exist;
- * otherwise, fails with -ENODATA.
- *
- * Returns 0 on success, -errno on failure.
- */
-int simple_xattr_set(struct simple_xattrs *xattrs, const char *name,
-		     const void *value, size_t size, int flags)
-{
-	if (size == 0)
-		value = ""; /* empty EA, do not remove */
-	return __simple_xattr_set(xattrs, name, value, size, flags);
-}
-
-/*
- * xattr REMOVE operation for in-memory/pseudo filesystems
- */
-int simple_xattr_remove(struct simple_xattrs *xattrs, const char *name)
+static bool xattr_is_trusted(const char *name)
 {
-	return __simple_xattr_set(xattrs, name, NULL, 0, XATTR_REPLACE);
+	return !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN);
 }
 
-static bool xattr_is_trusted(const char *name)
+static int xattr_list_one(char **buffer, ssize_t *remaining_size,
+			  const char *name)
 {
-	return !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN);
+	size_t len = strlen(name) + 1;
+	if (*buffer) {
+		if (*remaining_size < len)
+			return -ERANGE;
+		memcpy(*buffer, name, len);
+		*buffer += len;
+	}
+	*remaining_size -= len;
+	return 0;
 }
 
 /*
  * xattr LIST operation for in-memory/pseudo filesystems
  */
-ssize_t simple_xattr_list(struct simple_xattrs *xattrs, char *buffer,
-			  size_t size)
+ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs,
+			  char *buffer, size_t size)
 {
 	bool trusted = capable(CAP_SYS_ADMIN);
 	struct simple_xattr *xattr;
-	size_t used = 0;
+	ssize_t remaining_size = size;
+	int err;
+
+#ifdef CONFIG_FS_POSIX_ACL
+	if (inode->i_acl) {
+		err = xattr_list_one(&buffer, &remaining_size,
+				     XATTR_NAME_POSIX_ACL_ACCESS);
+		if (err)
+			return err;
+	}
+	if (inode->i_default_acl) {
+		err = xattr_list_one(&buffer, &remaining_size,
+				     XATTR_NAME_POSIX_ACL_DEFAULT);
+		if (err)
+			return err;
+	}
+#endif
 
 	spin_lock(&xattrs->lock);
 	list_for_each_entry(xattr, &xattrs->head, list) {
-		size_t len;
-
 		/* skip "trusted." attributes for unprivileged callers */
 		if (!trusted && xattr_is_trusted(xattr->name))
 			continue;
 
-		len = strlen(xattr->name) + 1;
-		used += len;
-		if (buffer) {
-			if (size < used) {
-				used = -ERANGE;
-				break;
-			}
-			memcpy(buffer, xattr->name, len);
-			buffer += len;
-		}
+		err = xattr_list_one(&buffer, &remaining_size, xattr->name);
+		if (err)
+			return err;
 	}
 	spin_unlock(&xattrs->lock);
 
-	return used;
+	return size - remaining_size;
 }
 
 /*