[PATCH v11 3/4] evm: Align evm_inode_init_security() definition with LSM infrastructure

[Mimi Zohar]

On Sat, 2023-06-03 at 21:15 +0200, Roberto Sassu wrote:
> From: Roberto Sassu <roberto.sassu at huawei.com>
> 
> Change the evm_inode_init_security() definition to align with the LSM
> infrastructure. Keep the existing behavior of including in the HMAC
> calculation only the first xattr provided by LSMs.
> 
> Changing the evm_inode_init_security() definition requires passing the
> xattr array allocated by security_inode_init_security(), and the number of
> xattrs filled by previously invoked LSMs.
> 
> Use the newly introduced lsm_get_xattr_slot() to position EVM correctly in
> the xattrs array, like a regular LSM, and to increment the number of filled
> slots. For now, the LSM infrastructure allocates enough xattrs slots to
> store the EVM xattr, without using the reservation mechanism.
> 
> Signed-off-by: Roberto Sassu <roberto.sassu at huawei.com>

Reviewed-by: Mimi Zohar <zohar at linux.ibm.com>