vfs: move getname() from callers to do_mount()

It would make more sense to pass char __user * instead of
char * in callers of do_mount() and do getname() inside do_mount().

Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Seunghun Lee <waydi1@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

4 files changed, 21 insertions, 44 deletions

diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index 1402fcc11c2c..f9c732e18284 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -446,7 +446,8 @@ struct procfs_args {
  * unhappy with OSF UFS. [CHECKME]
  */
 static int
-osf_ufs_mount(const char *dirname, struct ufs_args __user *args, int flags)
+osf_ufs_mount(const char __user *dirname,
+              struct ufs_args __user *args, int flags)
 {
         int retval;
         struct cdfs_args tmp;
@@ -466,7 +467,8 @@ osf_ufs_mount(const char *dirname, struct ufs_args __user *args, int flags)
 }
 
 static int
-osf_cdfs_mount(const char *dirname, struct cdfs_args __user *args, int flags)
+osf_cdfs_mount(const char __user *dirname,
+               struct cdfs_args __user *args, int flags)
 {
         int retval;
         struct cdfs_args tmp;
@@ -486,7 +488,8 @@ osf_cdfs_mount(const char *dirname, struct cdfs_args __user *args, int flags)
 }
 
 static int
-osf_procfs_mount(const char *dirname, struct procfs_args __user *args, int flags)
+osf_procfs_mount(const char __user *dirname,
+                 struct procfs_args __user *args, int flags)
 {
         struct procfs_args tmp;
 
@@ -500,28 +503,22 @@ SYSCALL_DEFINE4(osf_mount, unsigned long, typenr, const char __user *, path,
                 int, flag, void __user *, data)
 {
         int retval;
-        struct filename *name;
 
-        name = getname(path);
-        retval = PTR_ERR(name);
-        if (IS_ERR(name))
-                goto out;
         switch (typenr) {
         case 1:
-                retval = osf_ufs_mount(name->name, data, flag);
+                retval = osf_ufs_mount(path, data, flag);
                 break;
         case 6:
-                retval = osf_cdfs_mount(name->name, data, flag);
+                retval = osf_cdfs_mount(path, data, flag);
                 break;
         case 9:
-                retval = osf_procfs_mount(name->name, data, flag);
+                retval = osf_procfs_mount(path, data, flag);
                 break;
         default:
                 retval = -EINVAL;
                 printk("osf_mount(%ld, %x)\n", typenr, flag);
         }
-        putname(name);
- out:
+
         return retval;
 }
 
diff --git a/fs/compat.c b/fs/compat.c
index 6205c247a6e3..b13df99f3534 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -794,7 +794,6 @@ COMPAT_SYSCALL_DEFINE5(mount, const char __user *, dev_name,
         char *kernel_type;
         unsigned long data_page;
         char *kernel_dev;
-        struct filename *dir;
         int retval;
 
         kernel_type = copy_mount_string(type);
@@ -802,19 +801,14 @@ COMPAT_SYSCALL_DEFINE5(mount, const char __user *, dev_name,
         if (IS_ERR(kernel_type))
                 goto out;
 
-        dir = getname(dir_name);
-        retval = PTR_ERR(dir);
-        if (IS_ERR(dir))
-                goto out1;
-
         kernel_dev = copy_mount_string(dev_name);
         retval = PTR_ERR(kernel_dev);
         if (IS_ERR(kernel_dev))
-                goto out2;
+                goto out1;
 
         retval = copy_mount_options(data, &data_page);
         if (retval < 0)
-                goto out3;
+                goto out2;
 
         retval = -EINVAL;
 
@@ -823,19 +817,17 @@ COMPAT_SYSCALL_DEFINE5(mount, const char __user *, dev_name,
                         do_ncp_super_data_conv((void *)data_page);
                 } else if (!strcmp(kernel_type, NFS4_NAME)) {
                         if (do_nfs4_super_data_conv((void *) data_page))
-                                goto out4;
+                                goto out3;
                 }
         }
 
-        retval = do_mount(kernel_dev, dir->name, kernel_type,
+        retval = do_mount(kernel_dev, dir_name, kernel_type,
                         flags, (void*)data_page);
 
- out4:
-        free_page(data_page);
  out3:
-        kfree(kernel_dev);
+        free_page(data_page);
  out2:
-        putname(dir);
+        kfree(kernel_dev);
  out1:
         kfree(kernel_type);
  out:
diff --git a/fs/namespace.c b/fs/namespace.c
index abd3abb52616..348562f14e93 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2533,7 +2533,7 @@ char *copy_mount_string(const void __user *data)
  * Therefore, if this magic number is present, it carries no information
  * and must be discarded.
  */
-long do_mount(const char *dev_name, const char *dir_name,
+long do_mount(const char *dev_name, const char __user *dir_name,
                 const char *type_page, unsigned long flags, void *data_page)
 {
         struct path path;
@@ -2545,15 +2545,11 @@ long do_mount(const char *dev_name, const char *dir_name,
                 flags &= ~MS_MGC_MSK;
 
         /* Basic sanity checks */
-
-        if (!dir_name || !*dir_name || !memchr(dir_name, 0, PAGE_SIZE))
-                return -EINVAL;
-
         if (data_page)
                 ((char *)data_page)[PAGE_SIZE - 1] = 0;
 
         /* ... and get the mountpoint */
-        retval = kern_path(dir_name, LOOKUP_FOLLOW, &path);
+        retval = user_path(dir_name, &path);
         if (retval)
                 return retval;
 
@@ -2778,7 +2774,6 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
 {
         int ret;
         char *kernel_type;
-        struct filename *kernel_dir;
         char *kernel_dev;
         unsigned long data_page;
 
@@ -2787,12 +2782,6 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
         if (IS_ERR(kernel_type))
                 goto out_type;
 
-        kernel_dir = getname(dir_name);
-        if (IS_ERR(kernel_dir)) {
-                ret = PTR_ERR(kernel_dir);
-                goto out_dir;
-        }
-
         kernel_dev = copy_mount_string(dev_name);
         ret = PTR_ERR(kernel_dev);
         if (IS_ERR(kernel_dev))
@@ -2802,15 +2791,13 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
         if (ret < 0)
                 goto out_data;
 
-        ret = do_mount(kernel_dev, kernel_dir->name, kernel_type, flags,
+        ret = do_mount(kernel_dev, dir_name, kernel_type, flags,
                 (void *) data_page);
 
         free_page(data_page);
 out_data:
         kfree(kernel_dev);
 out_dev:
-        putname(kernel_dir);
-out_dir:
         kfree(kernel_type);
 out_type:
         return ret;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 75bdd51ec9b8..92148361bef8 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1855,7 +1855,8 @@ extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
 extern void kern_unmount(struct vfsmount *mnt);
 extern int may_umount_tree(struct vfsmount *);
 extern int may_umount(struct vfsmount *);
-extern long do_mount(const char *, const char *, const char *, unsigned long, void *);
+extern long do_mount(const char *, const char __user *,
+                     const char *, unsigned long, void *);
 extern struct vfsmount *collect_mounts(struct path *);
 extern void drop_collected_mounts(struct vfsmount *);
 extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,