Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759891AbXIUOIq (ORCPT ); Fri, 21 Sep 2007 10:08:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759387AbXIUOIe (ORCPT ); Fri, 21 Sep 2007 10:08:34 -0400 Received: from mx1.redhat.com ([66.187.233.31]:37000 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758140AbXIUOIc (ORCPT ); Fri, 21 Sep 2007 10:08:32 -0400 Message-ID: <46F3D049.4080006@redhat.com> Date: Fri, 21 Sep 2007 16:08:09 +0200 From: Michal Schmidt User-Agent: Thunderbird 2.0.0.5 (X11/20070727) MIME-Version: 1.0 To: Linux Kernel list CC: Frank Cusack , Matt Domsch , linux-ppp@vger.kernel.org Subject: [PATCH] ppp_mppe: Don't put InterimKey on the stack X-Enigmail-Version: 0.95.2 Content-Type: text/plain; charset=ISO-8859-2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2521 Lines: 69 Hello, The interrupt stack can be in the __START_KERNEL_map region in which virt_to_page will not work. This caused ppp_mppe to crash on CentOS 5 on x86_64 (http://bugs.centos.org/view.php?id=2076). The fix is to avoid copying the interim key. We can simply use it in its original place, which is kmalloc'd. Michal --- drivers/net/ppp_mppe.c | 14 ++++++-------- 1 files changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/net/ppp_mppe.c b/drivers/net/ppp_mppe.c index f79cf87..c0b6d19 100644 --- 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 ppp_mppe_state * state, unsigned char *I 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 ppp_mppe_state * state, unsigned char *I */ 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 */ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/