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27 March 2024, 02:37:15 UTC
Revision 9b284cbdb5de3b8871014f8290d1b540e5181c21 authored by Linus Torvalds on 05 July 2015, 02:11:33 UTC, committed by Linus Torvalds on 05 July 2015, 02:11:33 UTC 
bluetooth: fix list handling
 
Commit 835a6a2f8603 ("Bluetooth: Stop sabotaging list poisoning")
thought that the code was sabotaging the list poisoning when NULL'ing
out the list pointers and removed it.

But what was going on was that the bluetooth code was using NULL
pointers for the list as a way to mark it empty, and that commit just
broke it (and replaced the test with NULL with a "list_empty()" test on
a uninitialized list instead, breaking things even further).

So fix it all up to use the regular and real list_empty() handling
(which does not use NULL, but a pointer to itself), also making sure to
initialize the list properly (the previous NULL case was initialized
implicitly by the session being allocated with kzalloc())

This is a combination of patches by Marcel Holtmann and Tedd Ho-Jeong
An.

[ I would normally expect to get this through the bt tree, but I'm going
  to release -rc1, so I'm just committing this directly   - Linus ]

Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Original-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Original-by: Marcel Holtmann <marcel@holtmann.org>:
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 5c755fe
Raw File
Tip revision: 9b284cbdb5de3b8871014f8290d1b540e5181c21 authored by Linus Torvalds on 05 July 2015, 02:11:33 UTC
bluetooth: fix list handling
Tip revision: 9b284cb
cipher.c 
/*
 * Cryptographic API.
 *
 * Cipher operations.
 *
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 */

#include <linux/kernel.h>
#include <linux/crypto.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include "internal.h"

static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key,
			    unsigned int keylen)
{
	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	int ret;
	u8 *buffer, *alignbuffer;
	unsigned long absize;

	absize = keylen + alignmask;
	buffer = kmalloc(absize, GFP_ATOMIC);
	if (!buffer)
		return -ENOMEM;

	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	memcpy(alignbuffer, key, keylen);
	ret = cia->cia_setkey(tfm, alignbuffer, keylen);
	memset(alignbuffer, 0, keylen);
	kfree(buffer);
	return ret;

}

static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
{
	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);

	tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
	if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize) {
		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
		return -EINVAL;
	}

	if ((unsigned long)key & alignmask)
		return setkey_unaligned(tfm, key, keylen);

	return cia->cia_setkey(tfm, key, keylen);
}

static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *,
					      const u8 *),
				   struct crypto_tfm *tfm,
				   u8 *dst, const u8 *src)
{
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	unsigned int size = crypto_tfm_alg_blocksize(tfm);
	u8 buffer[size + alignmask];
	u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);

	memcpy(tmp, src, size);
	fn(tfm, tmp, tmp);
	memcpy(dst, tmp, size);
}

static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
				     u8 *dst, const u8 *src)
{
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;

	if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
		cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
		return;
	}

	cipher->cia_encrypt(tfm, dst, src);
}

static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
				     u8 *dst, const u8 *src)
{
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;

	if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
		cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);
		return;
	}

	cipher->cia_decrypt(tfm, dst, src);
}

int crypto_init_cipher_ops(struct crypto_tfm *tfm)
{
	struct cipher_tfm *ops = &tfm->crt_cipher;
	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;

	ops->cit_setkey = setkey;
	ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?
		cipher_encrypt_unaligned : cipher->cia_encrypt;
	ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
		cipher_decrypt_unaligned : cipher->cia_decrypt;

	return 0;
}

void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
{
}
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