[PATCH v1] ipe: add 'anonymous_memory' property for policy decisions

[Fan Wu]

After further testing I found the current approach, i.e. checking the existence of a struct file, does not work with memfd, which does use anonymous memory but also has a file struct in the kernel. There might be other cases that I also need to cover.
I will redesign the implementation and send another version in the future.


-Fan

On 2024/10/24 15:13, Fan Wu wrote:
> Since this patch is quite straightforward, I have merged it into the ipe#next branch for testing and will send it to Linus during the next merge window.
>
>
> -Fan
>
> On 2024/10/10 10:42, Fan Wu wrote:
>> Currently, all existing IPE properties evaluate to FALSE for
>> operations triggered by anonymous memory regions. As a result,
>> IPE falls back to the policy's default action for such operations.
>>
>> In policies where the default action is DENY, this behavior blocks
>> all anonymous memory operations, rendering binaries that rely on
>> anonymous memory unusable.
>>
>> This commit introduces a new IPE property, 'anonymous_memory',
>> which evaluates to TRUE when an operation is triggered by an
>> anonymous memory region. This allows administrators to explicitly
>> allow or deny operations involving anonymous memory.
>>
>> Signed-off-by: Fan Wu <wufan at linux.microsoft.com>
>> ---
>>  Documentation/admin-guide/LSM/ipe.rst | 11 +++++++++++
>>  Documentation/security/ipe.rst        |  9 +++++----
>>  security/ipe/Kconfig                  | 10 ++++++++++
>>  security/ipe/audit.c                  |  2 ++
>>  security/ipe/eval.c                   | 26 ++++++++++++++++++++++++++
>>  security/ipe/policy.h                 |  2 ++
>>  security/ipe/policy_parser.c          |  4 ++++
>>  7 files changed, 60 insertions(+), 4 deletions(-)