fscrypto: move ioctl processing more fully into common code

Multiple bugs were recently fixed in the "set encryption policy" ioctl.
To make it clear that fscrypt_process_policy() and fscrypt_get_policy()
implement ioctls and therefore their implementations must take standard
security and correctness precautions, rename them to
fscrypt_ioctl_set_policy() and fscrypt_ioctl_get_policy().  Make the
latter take in a struct file * to make it consistent with the former.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 2 insertions, 17 deletions

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index c7865073cd26..f0c83f74557d 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -1752,31 +1752,16 @@ static bool uuid_is_nonzero(__u8 u[16])
 
 static int f2fs_ioc_set_encryption_policy(struct file *filp, unsigned long arg)
 {
-	struct fscrypt_policy policy;
 	struct inode *inode = file_inode(filp);
 
-	if (copy_from_user(&policy, (struct fscrypt_policy __user *)arg,
-							sizeof(policy)))
-		return -EFAULT;
-
 	f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
 
-	return fscrypt_process_policy(filp, &policy);
+	return fscrypt_ioctl_set_policy(filp, (const void __user *)arg);
 }
 
 static int f2fs_ioc_get_encryption_policy(struct file *filp, unsigned long arg)
 {
-	struct fscrypt_policy policy;
-	struct inode *inode = file_inode(filp);
-	int err;
-
-	err = fscrypt_get_policy(inode, &policy);
-	if (err)
-		return err;
-
-	if (copy_to_user((struct fscrypt_policy __user *)arg, &policy, sizeof(policy)))
-		return -EFAULT;
-	return 0;
+	return fscrypt_ioctl_get_policy(filp, (void __user *)arg);
 }
 
 static int f2fs_ioc_get_encryption_pwsalt(struct file *filp, unsigned long arg)