Re: [PATCH] docs: fscrypt: document EFAULT return for FS_IOC_SET_ENCRYPTION_POLICY

[Eric Biggers <ebiggers@kernel.org>]

On Fri, Oct 10, 2025 at 09:17:53PM +0530, Divya Bharathi wrote:
> Signed-off-by: Divya Bharathi <divya27392@gmail.com>
> ---
>  Documentation/filesystems/fscrypt.rst | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst
> index 4a3e844b7..26cb409e3 100644
> --- a/Documentation/filesystems/fscrypt.rst
> +++ b/Documentation/filesystems/fscrypt.rst
> @@ -729,6 +729,8 @@ FS_IOC_SET_ENCRYPTION_POLICY can fail with the following errors:
>    version, mode(s), or flags; or reserved bits were set); or a v1
>    encryption policy was specified but the directory has the casefold
>    flag enabled (casefolding is incompatible with v1 policies).
> +- ``EFAULT``: an invalid pointer was passed for the encryption policy
> +  structure
>  - ``ENOKEY``: a v2 encryption policy was specified, but the key with
>    the specified ``master_key_identifier`` has not been added, nor does
>    the process have the CAP_FOWNER capability in the initial user
> -- 
> 2.51.0
> 

Thanks for the patch!

I think I omitted EFAULT intentionally, since it's always a possibility
for almost any ioctl or syscall that takes a pointer parameter.

If we'd like to explicitly document it, it probably should be documented
for all the ioctls in fscrypt.rst, rather than just
FS_IOC_SET_ENCRYPTION_POLICY.

Also, the list of error codes is alphabetized.  EFAULT should go into
the correct position in the list.

- Eric