s390/zcrypt: Guard domain index uses against speculative bypass

The previous array_index_nospec() placement only covered the admin
permission check, leaving ap_test_config_usage_domain() and
ap_test_config_ctrl_domain() in the CCA path exposed to speculative
execution.

Move the sanitization to before all permission and config checks in
both the CCA and EP11 paths. Hold the sanitized domain value in
another variable so that the later use can choose to use either the
original value (subject to speculative execution) or the sanitized
value (which may in case of AUTOSEL_DOM reflect the wrong
value). Before that, check the domain value to be either AUTOSEL_DOM
or in range 0...AP_DOMAINS-1 and return with -EINVAL in case this check
does not pass.

Fixes: e935cd525af4 ("s390/zcrypt: Close speculative mem read possibility")
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Cc: stable@vger.kernel.org
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

0 files changed, 0 insertions, 0 deletions