bcachefs: chardev: return -EFAULT if copy_to_user() fails

The copy_to_user() function returns the number of bytes remaining but
we want to return -EFAULT to the user.

Fixes: e0750d947352 ("bcachefs: Initial commit")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/chardev.c b/fs/bcachefs/chardev.c
index fb603df..e5e9fdd 100644 (file)
--- a/fs/bcachefs/chardev.c
+++ b/fs/bcachefs/chardev.c
@@ -149,9 +149,10 @@ static long bch2_global_ioctl(unsigned cmd, void __user *arg)
 static long bch2_ioctl_query_uuid(struct bch_fs *c,
                        struct bch_ioctl_query_uuid __user *user_arg)
 {
-       return copy_to_user(&user_arg->uuid,
-                           &c->sb.user_uuid,
-                           sizeof(c->sb.user_uuid));
+       if (copy_to_user(&user_arg->uuid, &c->sb.user_uuid,
+                        sizeof(c->sb.user_uuid)))
+               return -EFAULT;
+       return 0;
 }
 
 #if 0
@@ -338,7 +339,10 @@ static ssize_t bch2_data_job_read(struct file *file, char __user *buf,
        if (len < sizeof(e))
                return -EINVAL;
 
-       return copy_to_user(buf, &e, sizeof(e)) ?: sizeof(e);
+       if (copy_to_user(buf, &e, sizeof(e)))
+               return -EFAULT;
+
+       return sizeof(e);
 }
 
 static const struct file_operations bcachefs_data_ops = {
@@ -466,9 +470,11 @@ static long bch2_ioctl_fs_usage(struct bch_fs *c,
        percpu_up_read(&c->mark_lock);
        kfree(src);
 
-       if (!ret)
-               ret = copy_to_user(user_arg, arg,
-                       sizeof(*arg) + arg->replica_entries_bytes);
+       if (ret)
+               goto err;
+       if (copy_to_user(user_arg, arg,
+                        sizeof(*arg) + arg->replica_entries_bytes))
+               ret = -EFAULT;
 err:
        kfree(arg);
        return ret;
@@ -513,7 +519,10 @@ static long bch2_ioctl_dev_usage(struct bch_fs *c,
 
        percpu_ref_put(&ca->ref);
 
-       return copy_to_user(user_arg, &arg, sizeof(arg));
+       if (copy_to_user(user_arg, &arg, sizeof(arg)))
+               return -EFAULT;
+
+       return 0;
 }
 
 static long bch2_ioctl_read_super(struct bch_fs *c,
@@ -550,8 +559,9 @@ static long bch2_ioctl_read_super(struct bch_fs *c,
                goto err;
        }
 
-       ret = copy_to_user((void __user *)(unsigned long)arg.sb,
-                          sb, vstruct_bytes(sb));
+       if (copy_to_user((void __user *)(unsigned long)arg.sb, sb,
+                        vstruct_bytes(sb)))
+               ret = -EFAULT;
 err:
        if (!IS_ERR_OR_NULL(ca))
                percpu_ref_put(&ca->ref);