[kernel-hardening] Re: [PATCH v5 03/10] bpf: Define handle_fs and add a new helper bpf_handle_fs_get_mode()

Mickaël Salaün
2017-03-01T22:20:54Z

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On 01/03/2017 10:32, James Morris wrote:
> On Wed, 22 Feb 2017, Mickaël Salaün wrote:
>
>> Add an eBPF function bpf_handle_fs_get_mode(handle_fs) to get the mode
>> of a an abstract object wrapping either a file, a dentry, a path, or an
>> inode.
>>
>> Changes since v4:
>> * use a file abstraction (handle) to wrap inode, dentry, path and file
>> structs
>
> Good to see these abstractions. As discussed at LPC, we need to ensure
> that we don't couple the Landlock API too closely with the LSM API, as the
> former is an ABI exposed to userland -- we don't want to lose the ability
> to change LSM internally due to breaking Landlock policies.

Right, it is the case now, especially with the Landlock events.

>
>> @@ -82,6 +87,8 @@ enum bpf_arg_type {
>>
>> ARG_PTR_TO_CTX, /* pointer to context */
>> ARG_ANYTHING, /* any (initialized) argument is ok */
>> +
>> + ARG_CONST_PTR_TO_HANDLE_FS, /* pointer to an abstract FS struct */
>> };
>
> Extraneous whitespace?

It is on purpose, following the same rules as used for this enum.

Mickaël

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