Commit f2ebdadd authored by Holger Dengler's avatar Holger Dengler Committed by Alexander Gordeev
Browse files

s390/pkey: Wipe copies of protected- and secure-keys 



Although the clear-key of neither protected- nor secure-keys is
accessible, this key material should only be visible to the calling
process. So wipe all copies of protected- or secure-keys from stack,
even in case of an error.

Reviewed-by: default avatarHarald Freudenberger <freude@linux.ibm.com>
Reviewed-by: default avatarIngo Franzki <ifranzki@linux.ibm.com>
Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarHolger Dengler <dengler@linux.ibm.com>
Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent d65d76a4

drivers/s390/crypto/pkey_api.c

+37 −43
Original line number Diff line number Diff line
@@ -1359,10 +1359,9 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		rc = cca_genseckey(kgs.cardnr, kgs.domain,

				   kgs.keytype, kgs.seckey.seckey);

		pr_debug("%s cca_genseckey()=%d\n", __func__, rc);

		if (rc)

			break;

		if (copy_to_user(ugs, &kgs, sizeof(kgs)))

			return -EFAULT;

		if (!rc && copy_to_user(ugs, &kgs, sizeof(kgs)))

			rc = -EFAULT;

		memzero_explicit(&kgs, sizeof(kgs));

		break;

	}

	case PKEY_CLR2SECK: {
@@ -1390,10 +1389,9 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
				     ksp.seckey.seckey, ksp.protkey.protkey,

				     &ksp.protkey.len, &ksp.protkey.type);

		pr_debug("%s cca_sec2protkey()=%d\n", __func__, rc);

		if (rc)

			break;

		if (copy_to_user(usp, &ksp, sizeof(ksp)))

			return -EFAULT;

		if (!rc && copy_to_user(usp, &ksp, sizeof(ksp)))

			rc = -EFAULT;

		memzero_explicit(&ksp, sizeof(ksp));

		break;

	}

	case PKEY_CLR2PROTK: {
@@ -1437,10 +1435,9 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		rc = pkey_skey2pkey(ksp.seckey.seckey, ksp.protkey.protkey,

				    &ksp.protkey.len, &ksp.protkey.type);

		pr_debug("%s pkey_skey2pkey()=%d\n", __func__, rc);

		if (rc)

			break;

		if (copy_to_user(usp, &ksp, sizeof(ksp)))

			return -EFAULT;

		if (!rc && copy_to_user(usp, &ksp, sizeof(ksp)))

			rc = -EFAULT;

		memzero_explicit(&ksp, sizeof(ksp));

		break;

	}

	case PKEY_VERIFYKEY: {
@@ -1452,10 +1449,9 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		rc = pkey_verifykey(&kvk.seckey, &kvk.cardnr, &kvk.domain,

				    &kvk.keysize, &kvk.attributes);

		pr_debug("%s pkey_verifykey()=%d\n", __func__, rc);

		if (rc)

			break;

		if (copy_to_user(uvk, &kvk, sizeof(kvk)))

			return -EFAULT;

		if (!rc && copy_to_user(uvk, &kvk, sizeof(kvk)))

			rc = -EFAULT;

		memzero_explicit(&kvk, sizeof(kvk));

		break;

	}

	case PKEY_GENPROTK: {
@@ -1468,10 +1464,9 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		rc = pkey_genprotkey(kgp.keytype, kgp.protkey.protkey,

				     &kgp.protkey.len, &kgp.protkey.type);

		pr_debug("%s pkey_genprotkey()=%d\n", __func__, rc);

		if (rc)

			break;

		if (copy_to_user(ugp, &kgp, sizeof(kgp)))

			return -EFAULT;

		if (!rc && copy_to_user(ugp, &kgp, sizeof(kgp)))

			rc = -EFAULT;

		memzero_explicit(&kgp, sizeof(kgp));

		break;

	}

	case PKEY_VERIFYPROTK: {
@@ -1483,6 +1478,7 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		rc = pkey_verifyprotkey(kvp.protkey.protkey,

					kvp.protkey.len, kvp.protkey.type);

		pr_debug("%s pkey_verifyprotkey()=%d\n", __func__, rc);

		memzero_explicit(&kvp, sizeof(kvp));

		break;

	}

	case PKEY_KBLOB2PROTK: {
@@ -1500,10 +1496,9 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
				       &ktp.protkey.len, &ktp.protkey.type);

		pr_debug("%s pkey_keyblob2pkey()=%d\n", __func__, rc);

		kfree_sensitive(kkey);

		if (rc)

			break;

		if (copy_to_user(utp, &ktp, sizeof(ktp)))

			return -EFAULT;

		if (!rc && copy_to_user(utp, &ktp, sizeof(ktp)))

			rc = -EFAULT;

		memzero_explicit(&ktp, sizeof(ktp));

		break;

	}

	case PKEY_GENSECK2: {
@@ -1529,23 +1524,23 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		pr_debug("%s pkey_genseckey2()=%d\n", __func__, rc);

		kfree(apqns);

		if (rc) {

			kfree(kkey);

			kfree_sensitive(kkey);

			break;

		}

		if (kgs.key) {

			if (kgs.keylen < klen) {

				kfree(kkey);

				kfree_sensitive(kkey);

				return -EINVAL;

			}

			if (copy_to_user(kgs.key, kkey, klen)) {

				kfree(kkey);

				kfree_sensitive(kkey);

				return -EFAULT;

			}

		}

		kgs.keylen = klen;

		if (copy_to_user(ugs, &kgs, sizeof(kgs)))

			rc = -EFAULT;

		kfree(kkey);

		kfree_sensitive(kkey);

		break;

	}

	case PKEY_CLR2SECK2: {
@@ -1574,18 +1569,18 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		pr_debug("%s pkey_clr2seckey2()=%d\n", __func__, rc);

		kfree(apqns);

		if (rc) {

			kfree(kkey);

			kfree_sensitive(kkey);

			memzero_explicit(&kcs, sizeof(kcs));

			break;

		}

		if (kcs.key) {

			if (kcs.keylen < klen) {

				kfree(kkey);

				kfree_sensitive(kkey);

				memzero_explicit(&kcs, sizeof(kcs));

				return -EINVAL;

			}

			if (copy_to_user(kcs.key, kkey, klen)) {

				kfree(kkey);

				kfree_sensitive(kkey);

				memzero_explicit(&kcs, sizeof(kcs));

				return -EFAULT;

			}
@@ -1594,7 +1589,7 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		if (copy_to_user(ucs, &kcs, sizeof(kcs)))

			rc = -EFAULT;

		memzero_explicit(&kcs, sizeof(kcs));

		kfree(kkey);

		kfree_sensitive(kkey);

		break;

	}

	case PKEY_VERIFYKEY2: {
@@ -1611,7 +1606,7 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
				     &kvk.cardnr, &kvk.domain,

				     &kvk.type, &kvk.size, &kvk.flags);

		pr_debug("%s pkey_verifykey2()=%d\n", __func__, rc);

		kfree(kkey);

		kfree_sensitive(kkey);

		if (rc)

			break;

		if (copy_to_user(uvk, &kvk, sizeof(kvk)))
@@ -1642,10 +1637,9 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		pr_debug("%s pkey_keyblob2pkey2()=%d\n", __func__, rc);

		kfree(apqns);

		kfree_sensitive(kkey);

		if (rc)

			break;

		if (copy_to_user(utp, &ktp, sizeof(ktp)))

			return -EFAULT;

		if (!rc && copy_to_user(utp, &ktp, sizeof(ktp)))

			rc = -EFAULT;

		memzero_explicit(&ktp, sizeof(ktp));

		break;

	}

	case PKEY_APQNS4K: {
@@ -1673,7 +1667,7 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		rc = pkey_apqns4key(kkey, kak.keylen, kak.flags,

				    apqns, &nr_apqns);

		pr_debug("%s pkey_apqns4key()=%d\n", __func__, rc);

		kfree(kkey);

		kfree_sensitive(kkey);

		if (rc && rc != -ENOSPC) {

			kfree(apqns);

			break;
@@ -1759,7 +1753,7 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		protkey = kmalloc(protkeylen, GFP_KERNEL);

		if (!protkey) {

			kfree(apqns);

			kfree(kkey);

			kfree_sensitive(kkey);

			return -ENOMEM;

		}

		rc = pkey_keyblob2pkey3(apqns, ktp.apqn_entries,
@@ -1769,20 +1763,20 @@ static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd, 
		kfree(apqns);

		kfree_sensitive(kkey);

		if (rc) {

			kfree(protkey);

			kfree_sensitive(protkey);

			break;

		}

		if (ktp.pkey && ktp.pkeylen) {

			if (protkeylen > ktp.pkeylen) {

				kfree(protkey);

				kfree_sensitive(protkey);

				return -EINVAL;

			}

			if (copy_to_user(ktp.pkey, protkey, protkeylen)) {

				kfree(protkey);

				kfree_sensitive(protkey);

				return -EFAULT;

			}

		}

		kfree(protkey);

		kfree_sensitive(protkey);

		ktp.pkeylen = protkeylen;

		if (copy_to_user(utp, &ktp, sizeof(ktp)))

			return -EFAULT;