diff options
| -rw-r--r-- | crypto/cbc.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/crypto/cbc.c b/crypto/cbc.c index b013d6fec1e..6affff882cf 100644 --- a/crypto/cbc.c +++ b/crypto/cbc.c @@ -14,6 +14,7 @@ #include <linux/err.h> #include <linux/init.h> #include <linux/kernel.h> +#include <linux/log2.h> #include <linux/module.h> #include <linux/scatterlist.h> #include <linux/slab.h> @@ -143,17 +144,13 @@ static int crypto_cbc_decrypt_inplace(struct blkcipher_desc *desc, void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = crypto_cipher_alg(tfm)->cia_decrypt; int bsize = crypto_cipher_blocksize(tfm); - unsigned long alignmask = crypto_cipher_alignmask(tfm); unsigned int nbytes = walk->nbytes; u8 *src = walk->src.virt.addr; - u8 stack[bsize + alignmask]; - u8 *first_iv = (u8 *)ALIGN((unsigned long)stack, alignmask + 1); - - memcpy(first_iv, walk->iv, bsize); + u8 last_iv[bsize]; /* Start of the last block. */ - src += nbytes - nbytes % bsize - bsize; - memcpy(walk->iv, src, bsize); + src += nbytes - (nbytes & (bsize - 1)) - bsize; + memcpy(last_iv, src, bsize); for (;;) { fn(crypto_cipher_tfm(tfm), src, src); @@ -163,7 +160,8 @@ static int crypto_cbc_decrypt_inplace(struct blkcipher_desc *desc, src -= bsize; } - crypto_xor(src, first_iv, bsize); + crypto_xor(src, walk->iv, bsize); + memcpy(walk->iv, last_iv, bsize); return nbytes; } @@ -228,6 +226,10 @@ static struct crypto_instance *crypto_cbc_alloc(struct rtattr **tb) if (IS_ERR(alg)) return ERR_PTR(PTR_ERR(alg)); + inst = ERR_PTR(-EINVAL); + if (!is_power_of_2(alg->cra_blocksize)) + goto out_put_alg; + inst = crypto_alloc_instance("cbc", alg); if (IS_ERR(inst)) goto out_put_alg; |