[PATCH AUTOSEL 6.3 36/67] s390/pkey: zeroize key blobs

From: Sasha Levin
Date: Thu May 25 2023 - 14:36:06 EST


From: Holger Dengler <dengler@xxxxxxxxxxxxx>

[ Upstream commit 844cf829e5f33e00b279230470c8c93b58b8c16f ]

Key blobs for the IOCTLs PKEY_KBLOB2PROTK[23] may contain clear key
material. Zeroize the copies of these keys in kernel memory after
creating the protected key.

Reviewed-by: Harald Freudenberger <freude@xxxxxxxxxxxxx>
Signed-off-by: Holger Dengler <dengler@xxxxxxxxxxxxx>
Signed-off-by: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/s390/crypto/pkey_api.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/s390/crypto/pkey_api.c b/drivers/s390/crypto/pkey_api.c
index 5a05d1cdfec20..a8def50c149bd 100644
--- a/drivers/s390/crypto/pkey_api.c
+++ b/drivers/s390/crypto/pkey_api.c
@@ -1293,6 +1293,7 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd,
return PTR_ERR(kkey);
rc = pkey_keyblob2pkey(kkey, ktp.keylen, &ktp.protkey);
DEBUG_DBG("%s pkey_keyblob2pkey()=%d\n", __func__, rc);
+ memzero_explicit(kkey, ktp.keylen);
kfree(kkey);
if (rc)
break;
@@ -1426,6 +1427,7 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd,
kkey, ktp.keylen, &ktp.protkey);
DEBUG_DBG("%s pkey_keyblob2pkey2()=%d\n", __func__, rc);
kfree(apqns);
+ memzero_explicit(kkey, ktp.keylen);
kfree(kkey);
if (rc)
break;
@@ -1552,6 +1554,7 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd,
protkey, &protkeylen);
DEBUG_DBG("%s pkey_keyblob2pkey3()=%d\n", __func__, rc);
kfree(apqns);
+ memzero_explicit(kkey, ktp.keylen);
kfree(kkey);
if (rc) {
kfree(protkey);
--
2.39.2