Matt Domsch skrev: > On Fri, Sep 21, 2007 at 04:08:09PM +0200, Michal Schmidt wrote: > >> 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. >> > > Needs a Signed-off-by: line, but otherwise, looks good, and even saves > some stack space. Thanks for tracking this down. > > -Matt > Sorry about the forgotten sign-off. Here it is. Andrew, please apply. Signed-off-by: Michal Schmidt <mschmidt@xxxxxxxxxx> --- 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-ppp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
