saner calling conventions for copy_mount_options()

let it just return NULL, pointer to kernel copy or ERR_PTR().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 17 insertions, 18 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index b27156f2e68b..33a75c8e9fcb 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2601,18 +2601,18 @@ static long exact_copy_from_user(void *to, const void __user * from,
 	return n;
 }
 
-int copy_mount_options(const void __user * data, unsigned long *where)
+void *copy_mount_options(const void __user * data)
 {
 	int i;
-	unsigned long page;
 	unsigned long size;
+	char *copy;
 
-	*where = 0;
 	if (!data)
-		return 0;
+		return NULL;
 
-	if (!(page = __get_free_page(GFP_KERNEL)))
-		return -ENOMEM;
+	copy = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!copy)
+		return ERR_PTR(-ENOMEM);
 
 	/* We only care that *some* data at the address the user
 	 * gave us is valid.  Just in case, we'll zero
@@ -2623,15 +2623,14 @@ int copy_mount_options(const void __user * data, unsigned long *where)
 	if (size > PAGE_SIZE)
 		size = PAGE_SIZE;
 
-	i = size - exact_copy_from_user((void *)page, data, size);
+	i = size - exact_copy_from_user(copy, data, size);
 	if (!i) {
-		free_page(page);
-		return -EFAULT;
+		kfree(copy);
+		return ERR_PTR(-EFAULT);
 	}
 	if (i != PAGE_SIZE)
-		memset((char *)page + i, 0, PAGE_SIZE - i);
-	*where = page;
-	return 0;
+		memset(copy + i, 0, PAGE_SIZE - i);
+	return copy;
 }
 
 char *copy_mount_string(const void __user *data)
@@ -2896,7 +2895,7 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
 	int ret;
 	char *kernel_type;
 	char *kernel_dev;
-	unsigned long data_page;
+	void *options;
 
 	kernel_type = copy_mount_string(type);
 	ret = PTR_ERR(kernel_type);
@@ -2908,14 +2907,14 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
 	if (IS_ERR(kernel_dev))
 		goto out_dev;
 
-	ret = copy_mount_options(data, &data_page);
-	if (ret < 0)
+	options = copy_mount_options(data);
+	ret = PTR_ERR(options);
+	if (IS_ERR(options))
 		goto out_data;
 
-	ret = do_mount(kernel_dev, dir_name, kernel_type, flags,
-		(void *) data_page);
+	ret = do_mount(kernel_dev, dir_name, kernel_type, flags, options);
 
-	free_page(data_page);
+	kfree(options);
 out_data:
 	kfree(kernel_dev);
 out_dev: