bcachefs: Fix strndup_user() error checking

strndup_user() returns an error pointer, not NULL.

Reported-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 e8b6733e7f716708e4010e666dce6f7f72bbe893..f69e15dc699c9b6b22c07c8a1ce709bf478e57d8 100644 (file)
--- a/fs/bcachefs/chardev.c
+++ b/fs/bcachefs/chardev.c
@@ -86,10 +86,9 @@ static long bch2_ioctl_assemble(struct bch_ioctl_assemble __user *user_arg)
                devs[i] = strndup_user((const char __user *)(unsigned long)
                                       user_devs[i],
                                       PATH_MAX);
-               if (!devs[i]) {
-                       ret = -ENOMEM;
+               ret= PTR_ERR_OR_ZERO(devs[i]);
+               if (ret)
                        goto err;
-               }
        }
 
        c = bch2_fs_open(devs, arg.nr_devs, bch2_opts_empty());
@@ -117,8 +116,9 @@ static long bch2_ioctl_incremental(struct bch_ioctl_incremental __user *user_arg
                return -EINVAL;
 
        path = strndup_user((const char __user *)(unsigned long) arg.dev, PATH_MAX);
-       if (!path)
-               return -ENOMEM;
+       ret = PTR_ERR_OR_ZERO(path);
+       if (ret)
+               return ret;
 
        err = bch2_fs_open_incremental(path);
        kfree(path);
@@ -189,8 +189,9 @@ static long bch2_ioctl_disk_add(struct bch_fs *c, struct bch_ioctl_disk arg)
                return -EINVAL;
 
        path = strndup_user((const char __user *)(unsigned long) arg.dev, PATH_MAX);
-       if (!path)
-               return -ENOMEM;
+       ret = PTR_ERR_OR_ZERO(path);
+       if (ret)
+               return ret;
 
        ret = bch2_dev_add(c, path);
        kfree(path);
@@ -231,8 +232,9 @@ static long bch2_ioctl_disk_online(struct bch_fs *c, struct bch_ioctl_disk arg)
                return -EINVAL;
 
        path = strndup_user((const char __user *)(unsigned long) arg.dev, PATH_MAX);
-       if (!path)
-               return -ENOMEM;
+       ret = PTR_ERR_OR_ZERO(path);
+       if (ret)
+               return ret;
 
        ret = bch2_dev_online(c, path);
        kfree(path);