[PATCH 3/3] dm-crypt: don't use drivers that have CRYPTO_ALG_ALLOCATES_MEMORY

From: Mikulas Patocka
Date: Wed Jun 17 2020 - 11:11:23 EST


Don't use crypto drivers that have the flag CRYPTO_ALG_ALLOCATES_MEMORY
set. These drivers allocate memory and thus they are unsuitable for block
I/O processing.

Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>

---
drivers/md/dm-crypt.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

Index: linux-2.6/drivers/md/dm-crypt.c
===================================================================
--- linux-2.6.orig/drivers/md/dm-crypt.c
+++ linux-2.6/drivers/md/dm-crypt.c
@@ -419,7 +419,8 @@ static int crypt_iv_lmk_ctr(struct crypt
return -EINVAL;
}

- lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
+ lmk->hash_tfm = crypto_alloc_shash("md5", 0,
+ CRYPTO_ALG_ALLOCATES_MEMORY);
if (IS_ERR(lmk->hash_tfm)) {
ti->error = "Error initializing LMK hash";
return PTR_ERR(lmk->hash_tfm);
@@ -581,7 +582,8 @@ static int crypt_iv_tcw_ctr(struct crypt
return -EINVAL;
}

- tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0);
+ tcw->crc32_tfm = crypto_alloc_shash("crc32", 0,
+ CRYPTO_ALG_ALLOCATES_MEMORY);
if (IS_ERR(tcw->crc32_tfm)) {
ti->error = "Error initializing CRC32 in TCW";
return PTR_ERR(tcw->crc32_tfm);
@@ -768,7 +770,8 @@ static int crypt_iv_elephant_ctr(struct
struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
int r;

- elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
+ elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0,
+ CRYPTO_ALG_ALLOCATES_MEMORY);
if (IS_ERR(elephant->tfm)) {
r = PTR_ERR(elephant->tfm);
elephant->tfm = NULL;
@@ -2088,7 +2091,8 @@ static int crypt_alloc_tfms_skcipher(str
return -ENOMEM;

for (i = 0; i < cc->tfms_count; i++) {
- cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 0);
+ cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0,
+ CRYPTO_ALG_ALLOCATES_MEMORY);
if (IS_ERR(cc->cipher_tfm.tfms[i])) {
err = PTR_ERR(cc->cipher_tfm.tfms[i]);
crypt_free_tfms(cc);
@@ -2114,7 +2118,8 @@ static int crypt_alloc_tfms_aead(struct
if (!cc->cipher_tfm.tfms)
return -ENOMEM;

- cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 0);
+ cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0,
+ CRYPTO_ALG_ALLOCATES_MEMORY);
if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
crypt_free_tfms(cc);
@@ -2565,7 +2570,7 @@ static int crypt_ctr_auth_cipher(struct
return -ENOMEM;
strncpy(mac_alg, start, end - start);

- mac = crypto_alloc_ahash(mac_alg, 0, 0);
+ mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY);
kfree(mac_alg);

if (IS_ERR(mac))