[RFC PATCH v3 58/59] alpha: switch osf_mount() to strndup_user()

[Al Viro]

... same as native mount(2) is doing for devname argument.  While we
are at it, fix misspelling ufs_args as cdfs_args in osf_ufs_mount() -
layouts are identical, so it doesn't change anything, but the current
variant is confusing for no reason.

Signed-off-by: Al Viro <v...@zeniv.linux.org.uk>
---
 arch/alpha/kernel/osf_sys.c | 34 +++++++++++-----------------------
 1 file changed, 11 insertions(+), 23 deletions(-)

diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index a08e8edef1a4..7b6543d2cca3 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -454,42 +454,30 @@ static int
 osf_ufs_mount(const char __user *dirname,
              struct ufs_args __user *args, int flags)
 {
-       int retval;
-       struct cdfs_args tmp;
-       struct filename *devname;
+       struct ufs_args tmp;
+       char *devname __free(kfree) = NULL;
 
-       retval = -EFAULT;
        if (copy_from_user(&tmp, args, sizeof(tmp)))
-               goto out;
-       devname = getname(tmp.devname);
-       retval = PTR_ERR(devname);
+               return -EFAULT;
+       devname = strndup_user(tmp.devname, PATH_MAX);
        if (IS_ERR(devname))
-               goto out;
-       retval = do_mount(devname->name, dirname, "ext2", flags, NULL);
-       putname(devname);
- out:
-       return retval;
+               return PTR_ERR(devname);
+       return do_mount(devname, dirname, "ext2", flags, NULL);
 }
 
 static int
 osf_cdfs_mount(const char __user *dirname,
               struct cdfs_args __user *args, int flags)
 {
-       int retval;
        struct cdfs_args tmp;
-       struct filename *devname;
+       char *devname __free(kfree) = NULL;
 
-       retval = -EFAULT;
        if (copy_from_user(&tmp, args, sizeof(tmp)))
-               goto out;
-       devname = getname(tmp.devname);
-       retval = PTR_ERR(devname);
+               return -EFAULT;
+       devname = strndup_user(tmp.devname, PATH_MAX);
        if (IS_ERR(devname))
-               goto out;
-       retval = do_mount(devname->name, dirname, "iso9660", flags, NULL);
-       putname(devname);
- out:
-       return retval;
+               return PTR_ERR(devname);
+       return do_mount(devname, dirname, "iso9660", flags, NULL);
 }
 
 static int
-- 
2.47.3