[patch 06/12] Fix ppp_mppe kernel stack usage.

Greg KH
2007-10-08T18:21:53Z

[-- Attachment #1: fix-ppp_mppe-kernel-stack-usage.patch --]
[-- Type: text/plain, Size: 2055 bytes --]

From: Michal Schmidt <mschmidt@redhat.com>

commit 45dfd5b5dd20f17fe23dafc5cfe921474d27f849 from upstream

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/net/ppp_mppe.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)

--- a/drivers/net/ppp_mppe.c
+++ b/drivers/net/ppp_mppe.c
@@ -136,7 +136,7 @@ struct ppp_mppe_state {
* Key Derivation, from RFC 3078, RFC 3079.
* Equivalent to Get_Key() for MS-CHAP as described in RFC 3079.
*/
-static void get_new_key_from_sha(struct ppp_mppe_state * state, unsigned char *InterimKey)
+static void get_new_key_from_sha(struct ppp_mppe_state * state)
{
struct hash_desc desc;
struct scatterlist sg[4];
@@ -153,8 +153,6 @@ static void get_new_key_from_sha(struct
desc.flags = 0;

crypto_hash_digest(&desc, sg, nbytes, state->sha1_digest);
-
- memcpy(InterimKey, state->sha1_digest, state->keylen);
}

/*
@@ -163,21 +161,21 @@ static void get_new_key_from_sha(struct
*/
static void mppe_rekey(struct ppp_mppe_state * state, int initial_key)
{
- unsigned char InterimKey[MPPE_MAX_KEY_LEN];
struct scatterlist sg_in[1], sg_out[1];
struct blkcipher_desc desc = { .tfm = state->arc4 };

- get_new_key_from_sha(state, InterimKey);
+ get_new_key_from_sha(state);
if (!initial_key) {
- crypto_blkcipher_setkey(state->arc4, InterimKey, state->keylen);
- setup_sg(sg_in, InterimKey, state->keylen);
+ crypto_blkcipher_setkey(state->arc4, state->sha1_digest,
+ state->keylen);
+ setup_sg(sg_in, state->sha1_digest, state->keylen);
setup_sg(sg_out, state->session_key, state->keylen);
if (crypto_blkcipher_encrypt(&desc, sg_out, sg_in,
state->keylen) != 0) {
printk(KERN_WARNING "mppe_rekey: cipher_encrypt failed\n");
}
} else {
- memcpy(state->session_key, InterimKey, state->keylen);
+ memcpy(state->session_key, state->sha1_digest, state->keylen);
}
if (state->keylen == 8) {
/* See RFC 3078 */

--