tree e4a1c5fd8871eaba1b2bb0b65405d9cb0d4bd6f6
parent 14503eb99414ceffe348b82982d5770b745f6626
author Mimi Zohar <zohar@linux.vnet.ibm.com> 1399781123 -0400
committer Mimi Zohar <zohar@linux.vnet.ibm.com> 1402610287 -0400

evm: prohibit userspace writing 'security.evm' HMAC value

Calculating the 'security.evm' HMAC value requires access to the
EVM encrypted key.  Only the kernel should have access to it.  This
patch prevents userspace tools(eg. setfattr, cp --preserve=xattr)
from setting/modifying the 'security.evm' HMAC value directly.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>