This is a note to let you know that I've just added the patch titled
KEYS: trusted: sanitize all key material
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
keys-trusted-sanitize-all-key-material.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ee618b4619b72527aaed765f0f0b74072b281159 Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers@xxxxxxxxxx>
Date: Thu, 8 Jun 2017 14:49:18 +0100
Subject: KEYS: trusted: sanitize all key material
From: Eric Biggers <ebiggers@xxxxxxxxxx>
commit ee618b4619b72527aaed765f0f0b74072b281159 upstream.
As the previous patch did for encrypted-keys, zero sensitive any
potentially sensitive data related to the "trusted" key type before it
is freed. Notably, we were not zeroing the tpm_buf structures in which
the actual key is stored for TPM seal and unseal, nor were we zeroing
the trusted_key_payload in certain error paths.
Cc: Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx>
Cc: David Safford <safford@xxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: James Morris <james.l.morris@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
security/keys/trusted.c | 50 +++++++++++++++++++++---------------------------
1 file changed, 22 insertions(+), 28 deletions(-)
--- a/security/keys/trusted.c
+++ b/security/keys/trusted.c
@@ -70,7 +70,7 @@ static int TSS_sha1(const unsigned char
}
ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest);
- kfree(sdesc);
+ kzfree(sdesc);
return ret;
}
@@ -114,7 +114,7 @@ static int TSS_rawhmac(unsigned char *di
if (!ret)
ret = crypto_shash_final(&sdesc->shash, digest);
out:
- kfree(sdesc);
+ kzfree(sdesc);
return ret;
}
@@ -165,7 +165,7 @@ static int TSS_authhmac(unsigned char *d
paramdigest, TPM_NONCE_SIZE, h1,
TPM_NONCE_SIZE, h2, 1, &c, 0, 0);
out:
- kfree(sdesc);
+ kzfree(sdesc);
return ret;
}
@@ -246,7 +246,7 @@ static int TSS_checkhmac1(unsigned char
if (memcmp(testhmac, authdata, SHA1_DIGEST_SIZE))
ret = -EINVAL;
out:
- kfree(sdesc);
+ kzfree(sdesc);
return ret;
}
@@ -347,7 +347,7 @@ static int TSS_checkhmac2(unsigned char
if (memcmp(testhmac2, authdata2, SHA1_DIGEST_SIZE))
ret = -EINVAL;
out:
- kfree(sdesc);
+ kzfree(sdesc);
return ret;
}
@@ -564,7 +564,7 @@ static int tpm_seal(struct tpm_buf *tb,
*bloblen = storedsize;
}
out:
- kfree(td);
+ kzfree(td);
return ret;
}
@@ -678,7 +678,7 @@ static int key_seal(struct trusted_key_p
if (ret < 0)
pr_info("trusted_key: srkseal failed (%d)\n", ret);
- kfree(tb);
+ kzfree(tb);
return ret;
}
@@ -703,7 +703,7 @@ static int key_unseal(struct trusted_key
/* pull migratable flag out of sealed key */
p->migratable = p->key[--p->key_len];
- kfree(tb);
+ kzfree(tb);
return ret;
}
@@ -1037,12 +1037,12 @@ static int trusted_instantiate(struct ke
if (!ret && options->pcrlock)
ret = pcrlock(options->pcrlock);
out:
- kfree(datablob);
- kfree(options);
+ kzfree(datablob);
+ kzfree(options);
if (!ret)
rcu_assign_keypointer(key, payload);
else
- kfree(payload);
+ kzfree(payload);
return ret;
}
@@ -1051,8 +1051,7 @@ static void trusted_rcu_free(struct rcu_
struct trusted_key_payload *p;
p = container_of(rcu, struct trusted_key_payload, rcu);
- memset(p->key, 0, p->key_len);
- kfree(p);
+ kzfree(p);
}
/*
@@ -1094,13 +1093,13 @@ static int trusted_update(struct key *ke
ret = datablob_parse(datablob, new_p, new_o);
if (ret != Opt_update) {
ret = -EINVAL;
- kfree(new_p);
+ kzfree(new_p);
goto out;
}
if (!new_o->keyhandle) {
ret = -EINVAL;
- kfree(new_p);
+ kzfree(new_p);
goto out;
}
@@ -1114,22 +1113,22 @@ static int trusted_update(struct key *ke
ret = key_seal(new_p, new_o);
if (ret < 0) {
pr_info("trusted_key: key_seal failed (%d)\n", ret);
- kfree(new_p);
+ kzfree(new_p);
goto out;
}
if (new_o->pcrlock) {
ret = pcrlock(new_o->pcrlock);
if (ret < 0) {
pr_info("trusted_key: pcrlock failed (%d)\n", ret);
- kfree(new_p);
+ kzfree(new_p);
goto out;
}
}
rcu_assign_keypointer(key, new_p);
call_rcu(&p->rcu, trusted_rcu_free);
out:
- kfree(datablob);
- kfree(new_o);
+ kzfree(datablob);
+ kzfree(new_o);
return ret;
}
@@ -1158,24 +1157,19 @@ static long trusted_read(const struct ke
for (i = 0; i < p->blob_len; i++)
bufp = hex_byte_pack(bufp, p->blob[i]);
if ((copy_to_user(buffer, ascii_buf, 2 * p->blob_len)) != 0) {
- kfree(ascii_buf);
+ kzfree(ascii_buf);
return -EFAULT;
}
- kfree(ascii_buf);
+ kzfree(ascii_buf);
return 2 * p->blob_len;
}
/*
- * trusted_destroy - before freeing the key, clear the decrypted data
+ * trusted_destroy - clear and free the key's payload
*/
static void trusted_destroy(struct key *key)
{
- struct trusted_key_payload *p = key->payload.data[0];
-
- if (!p)
- return;
- memset(p->key, 0, p->key_len);
- kfree(key->payload.data[0]);
+ kzfree(key->payload.data[0]);
}
struct key_type key_type_trusted = {
Patches currently in stable-queue which might be from ebiggers@xxxxxxxxxx are
queue-4.9/keys-trusted-sanitize-all-key-material.patch
queue-4.9/keys-trusted-fix-writing-past-end-of-buffer-in-trusted_read.patch