Revision 7ab02af428c2d312c0cf8fb0b01cc1eb21131a3d authored by Linus Torvalds on 02 February 2010, 20:37:44 UTC, committed by Linus Torvalds on 02 February 2010, 20:37:44 UTC
Commit 221af7f87b9 ("Split 'flush_old_exec' into two functions") split the function at the point of no return - ie right where there were no more error cases to check. That made sense from a technical standpoint, but when we then also combined it with the actual personality setting going in between flush_old_exec() and setup_new_exec(), it needs to be a bit more careful. In particular, we need to make sure that we really flush the old personality bits in the 'flush' stage, rather than later in the 'setup' stage, since otherwise we might be flushing the _new_ personality state that we're just setting up. So this moves the flags and personality flushing (and 'flush_thread()', which is the arch-specific function that generally resets lazy FP state etc) of the old process into flush_old_exec(), so that it doesn't affect any state that execve() is setting up for the new process environment. This was reported by Michal Simek as breaking his Microblaze qemu environment. Reported-and-tested-by: Michal Simek <michal.simek@petalogix.com> Cc: Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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michael_mic.c
/*
* Cryptographic API
*
* Michael MIC (IEEE 802.11i/TKIP) keyed digest
*
* Copyright (c) 2004 Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <crypto/internal/hash.h>
#include <asm/byteorder.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/types.h>
struct michael_mic_ctx {
u32 l, r;
};
struct michael_mic_desc_ctx {
u8 pending[4];
size_t pending_len;
u32 l, r;
};
static inline u32 xswap(u32 val)
{
return ((val & 0x00ff00ff) << 8) | ((val & 0xff00ff00) >> 8);
}
#define michael_block(l, r) \
do { \
r ^= rol32(l, 17); \
l += r; \
r ^= xswap(l); \
l += r; \
r ^= rol32(l, 3); \
l += r; \
r ^= ror32(l, 2); \
l += r; \
} while (0)
static int michael_init(struct shash_desc *desc)
{
struct michael_mic_desc_ctx *mctx = shash_desc_ctx(desc);
struct michael_mic_ctx *ctx = crypto_shash_ctx(desc->tfm);
mctx->pending_len = 0;
mctx->l = ctx->l;
mctx->r = ctx->r;
return 0;
}
static int michael_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
struct michael_mic_desc_ctx *mctx = shash_desc_ctx(desc);
const __le32 *src;
if (mctx->pending_len) {
int flen = 4 - mctx->pending_len;
if (flen > len)
flen = len;
memcpy(&mctx->pending[mctx->pending_len], data, flen);
mctx->pending_len += flen;
data += flen;
len -= flen;
if (mctx->pending_len < 4)
return 0;
src = (const __le32 *)mctx->pending;
mctx->l ^= le32_to_cpup(src);
michael_block(mctx->l, mctx->r);
mctx->pending_len = 0;
}
src = (const __le32 *)data;
while (len >= 4) {
mctx->l ^= le32_to_cpup(src++);
michael_block(mctx->l, mctx->r);
len -= 4;
}
if (len > 0) {
mctx->pending_len = len;
memcpy(mctx->pending, src, len);
}
return 0;
}
static int michael_final(struct shash_desc *desc, u8 *out)
{
struct michael_mic_desc_ctx *mctx = shash_desc_ctx(desc);
u8 *data = mctx->pending;
__le32 *dst = (__le32 *)out;
/* Last block and padding (0x5a, 4..7 x 0) */
switch (mctx->pending_len) {
case 0:
mctx->l ^= 0x5a;
break;
case 1:
mctx->l ^= data[0] | 0x5a00;
break;
case 2:
mctx->l ^= data[0] | (data[1] << 8) | 0x5a0000;
break;
case 3:
mctx->l ^= data[0] | (data[1] << 8) | (data[2] << 16) |
0x5a000000;
break;
}
michael_block(mctx->l, mctx->r);
/* l ^= 0; */
michael_block(mctx->l, mctx->r);
dst[0] = cpu_to_le32(mctx->l);
dst[1] = cpu_to_le32(mctx->r);
return 0;
}
static int michael_setkey(struct crypto_shash *tfm, const u8 *key,
unsigned int keylen)
{
struct michael_mic_ctx *mctx = crypto_shash_ctx(tfm);
const __le32 *data = (const __le32 *)key;
if (keylen != 8) {
crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
return -EINVAL;
}
mctx->l = le32_to_cpu(data[0]);
mctx->r = le32_to_cpu(data[1]);
return 0;
}
static struct shash_alg alg = {
.digestsize = 8,
.setkey = michael_setkey,
.init = michael_init,
.update = michael_update,
.final = michael_final,
.descsize = sizeof(struct michael_mic_desc_ctx),
.base = {
.cra_name = "michael_mic",
.cra_blocksize = 8,
.cra_alignmask = 3,
.cra_ctxsize = sizeof(struct michael_mic_ctx),
.cra_module = THIS_MODULE,
}
};
static int __init michael_mic_init(void)
{
return crypto_register_shash(&alg);
}
static void __exit michael_mic_exit(void)
{
crypto_unregister_shash(&alg);
}
module_init(michael_mic_init);
module_exit(michael_mic_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Michael MIC");
MODULE_AUTHOR("Jouni Malinen <j@w1.fi>");
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