s390/zcrypt: Fix wrong domain value verification with EP11 CPRBs

There is a wrong upper limit check for the domain value when an EP11
CPRB is processed for sending to a crypto card. This check is only
active on custom device nodes but may lead to access heap memory
behind perms->adm when an administrative CPRB is sent.
Add correct limit (AP_DOMAINS = 256) checking to fix this.

Fixes: cfd68b3309 ("s390/zcrypt: Filter admin CPRBs on custom devices")
Cc: stable@vger.kernel.org
Reviewed-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Harald Freudenberger 2026-07-23 11:54:52 +02:00 committed by Vasily Gorbik
parent 36b230835b
commit 983279d7f8

View File

@ -1077,7 +1077,7 @@ static long _zcrypt_send_ep11_cprb(u32 xflags, struct ap_perms *perms,
print_hex_dump_debug("ep11req: ", DUMP_PREFIX_ADDRESS, 16, 1,
ap_msg.msg, ap_msg.len, false);
if (perms != &ap_perms && domain < AUTOSEL_DOM) {
if (perms != &ap_perms && domain < AP_DOMAINS) {
if (ap_msg.flags & AP_MSG_FLAG_ADMIN) {
if (!test_bit_inv(domain, perms->adm)) {
rc = -ENODEV;