Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux

1 files changed, 29 insertions, 20 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index 0570729c87fd..a830e1463704 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1584,6 +1584,14 @@ static inline bool may_mount(void)
 	return ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN);
 }
 
+static inline bool may_mandlock(void)
+{
+#ifndef	CONFIG_MANDATORY_FILE_LOCKING
+	return false;
+#endif
+	return capable(CAP_SYS_ADMIN);
+}
+
 /*
  * Now umount can handle mount points as well as block devices.
  * This is important for filesystems which use unnamed block devices.
@@ -2601,18 +2609,18 @@ 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 +2631,14 @@ 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)
@@ -2677,6 +2684,8 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 				   type_page, flags, data_page);
 	if (!retval && !may_mount())
 		retval = -EPERM;
+	if (!retval && (flags & MS_MANDLOCK) && !may_mandlock())
+		retval = -EPERM;
 	if (retval)
 		goto dput_out;
 
@@ -2896,7 +2905,7 @@ 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 +2917,14 @@ 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:
@@ -2939,9 +2948,9 @@ bool is_path_reachable(struct mount *mnt, struct dentry *dentry,
 	return &mnt->mnt == root->mnt && is_subdir(dentry, root->dentry);
 }
 
-int path_is_under(struct path *path1, struct path *path2)
+bool path_is_under(struct path *path1, struct path *path2)
 {
-	int res;
+	bool res;
 	read_seqlock_excl(&mount_lock);
 	res = is_path_reachable(real_mount(path1->mnt), path1->dentry, path2);
 	read_sequnlock_excl(&mount_lock);