diff options
author | Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com> | 2014-02-05 11:29:57 (GMT) |
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committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2014-02-12 08:49:45 (GMT) |
commit | 63ef79c25b5bbd356d04ef93d15693d8664c6141 (patch) | |
tree | 54e737cf49c58399ddbff264fe719297a49af42e /drivers/s390/crypto | |
parent | 45f7fdc2ffb9d5af4dab593843e89da70d1259e3 (diff) | |
download | linux-63ef79c25b5bbd356d04ef93d15693d8664c6141.tar.xz |
s390/zcrypt: additional check to avoid overflow in msg-type 6 requests
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/crypto')
-rw-r--r-- | drivers/s390/crypto/zcrypt_msgtype6.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/drivers/s390/crypto/zcrypt_msgtype6.c b/drivers/s390/crypto/zcrypt_msgtype6.c index dc542e0..0bc91e4 100644 --- a/drivers/s390/crypto/zcrypt_msgtype6.c +++ b/drivers/s390/crypto/zcrypt_msgtype6.c @@ -311,7 +311,7 @@ static int XCRB_msg_to_type6CPRB_msgX(struct zcrypt_device *zdev, } __packed * msg = ap_msg->message; int rcblen = CEIL4(xcRB->request_control_blk_length); - int replylen; + int replylen, req_sumlen, resp_sumlen; char *req_data = ap_msg->message + sizeof(struct type6_hdr) + rcblen; char *function_code; @@ -321,12 +321,34 @@ static int XCRB_msg_to_type6CPRB_msgX(struct zcrypt_device *zdev, xcRB->request_data_length; if (ap_msg->length > MSGTYPE06_MAX_MSG_SIZE) return -EINVAL; + + /* Overflow check + sum must be greater (or equal) than the largest operand */ + req_sumlen = CEIL4(xcRB->request_control_blk_length) + + xcRB->request_data_length; + if ((CEIL4(xcRB->request_control_blk_length) <= + xcRB->request_data_length) ? + (req_sumlen < xcRB->request_data_length) : + (req_sumlen < CEIL4(xcRB->request_control_blk_length))) { + return -EINVAL; + } + replylen = sizeof(struct type86_fmt2_msg) + CEIL4(xcRB->reply_control_blk_length) + xcRB->reply_data_length; if (replylen > MSGTYPE06_MAX_MSG_SIZE) return -EINVAL; + /* Overflow check + sum must be greater (or equal) than the largest operand */ + resp_sumlen = CEIL4(xcRB->reply_control_blk_length) + + xcRB->reply_data_length; + if ((CEIL4(xcRB->reply_control_blk_length) <= xcRB->reply_data_length) ? + (resp_sumlen < xcRB->reply_data_length) : + (resp_sumlen < CEIL4(xcRB->reply_control_blk_length))) { + return -EINVAL; + } + /* prepare type6 header */ msg->hdr = static_type6_hdrX; memcpy(msg->hdr.agent_id , &(xcRB->agent_ID), sizeof(xcRB->agent_ID)); |