From: Mikulas Patocka <mpatocka@redhat.com>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>,
linux-crypto@vger.kernel.org, Mike Snitzer <msnitzer@redhat.com>,
Milan Broz <mbroz@redhat.com>,
dm-devel@redhat.com, linux-kernel@vger.kernel.org
Subject: [PATCH 1/4] crypto: introduce CRYPTO_ALG_ALLOCATES_MEMORY
Date: Tue, 16 Jun 2020 11:01:31 -0400 (EDT) [thread overview]
Message-ID: <alpine.LRH.2.02.2006161101080.28052@file01.intranet.prod.int.rdu2.redhat.com> (raw)
In-Reply-To: <alpine.LRH.2.02.2006161052540.28052@file01.intranet.prod.int.rdu2.redhat.com>
Introduce a new flag CRYPTO_ALG_ALLOCATES_MEMORY and modify dm-crypt, so
that it uses only drivers without this flag.
If the flag is set, then the crypto driver allocates memory in its request
routine. Such drivers are not suitable for disk encryption because
GFP_ATOMIC allocation can fail anytime (causing random I/O errors) and
GFP_KERNEL allocation can recurse into the block layer, causing a
deadlock.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Index: linux-2.6/include/linux/crypto.h
===================================================================
--- linux-2.6.orig/include/linux/crypto.h
+++ linux-2.6/include/linux/crypto.h
@@ -97,9 +97,15 @@
#define CRYPTO_ALG_OPTIONAL_KEY 0x00004000
/*
+ * The driver is allocating emmory in its encrypt or decrypt callback,
+ * so it should not be used to encrypt block devices.
+ */
+#define CRYPTO_ALG_ALLOCATES_MEMORY 0x00008000
+
+/*
* Don't trigger module loading
*/
-#define CRYPTO_NOLOAD 0x00008000
+#define CRYPTO_NOLOAD 0x00010000
/*
* Transform masks and values (for crt_flags).
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 +419,7 @@ 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 +581,7 @@ 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 +768,7 @@ 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 +2088,7 @@ 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 +2114,7 @@ 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 +2565,7 @@ 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))
next prev parent reply other threads:[~2020-06-16 15:01 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-09 17:11 crypto API and GFP_ATOMIC Mikulas Patocka
2020-06-10 1:04 ` Herbert Xu
2020-06-10 12:02 ` Mikulas Patocka
2020-06-10 12:11 ` Herbert Xu
2020-06-16 15:01 ` Mikulas Patocka
2020-06-16 15:01 ` Mikulas Patocka [this message]
2020-06-16 17:36 ` [dm-devel] [PATCH 1/4] crypto: introduce CRYPTO_ALG_ALLOCATES_MEMORY Eric Biggers
2020-06-17 15:08 ` Mikulas Patocka
2020-06-17 15:09 ` [PATCH 1/3] crypto: pass the flag CRYPTO_ALG_ALLOCATES_MEMORY Mikulas Patocka
2020-06-26 4:45 ` Herbert Xu
2020-06-26 15:17 ` Mikulas Patocka
2020-06-26 16:16 ` [PATCH 1/3 v2] crypto: introduce " Mikulas Patocka
2020-06-26 16:46 ` Eric Biggers
2020-06-26 17:00 ` [dm-devel] " Eric Biggers
2020-06-28 19:07 ` Mikulas Patocka
2020-06-28 19:50 ` Eric Biggers
2020-06-30 13:57 ` Mikulas Patocka
2020-06-28 20:00 ` Eric Biggers
2020-06-29 13:17 ` Mikulas Patocka
2020-06-30 13:45 ` Mikulas Patocka
2020-06-28 19:04 ` Mikulas Patocka
2020-06-28 19:46 ` Eric Biggers
2020-06-28 19:05 ` [PATCH 1/3 v3] " Mikulas Patocka
2020-06-30 13:56 ` [PATCH 1/3 v4] " Mikulas Patocka
2020-06-30 16:35 ` [dm-devel] " Eric Biggers
2020-06-30 17:01 ` Mikulas Patocka
2020-06-30 17:02 ` [PATCH 1/3 v5] " Mikulas Patocka
2020-06-30 17:57 ` [dm-devel] [PATCH 1/3 v4] " Eric Biggers
2020-06-30 18:14 ` Mikulas Patocka
2020-06-30 18:15 ` [PATCH 1/3 v6] " Mikulas Patocka
2020-07-01 1:49 ` Herbert Xu
2020-06-17 15:10 ` [PATCH 2/3] crypto: set " Mikulas Patocka
2020-06-17 15:11 ` [PATCH 3/3] dm-crypt: don't use drivers that have CRYPTO_ALG_ALLOCATES_MEMORY Mikulas Patocka
2020-06-16 15:01 ` [PATCH 2/4] crypto: pass the flag CRYPTO_ALG_ALLOCATES_MEMORY Mikulas Patocka
2020-06-16 17:42 ` [dm-devel] " Eric Biggers
2020-06-16 15:02 ` [PATCH 3/4] crypto: set " Mikulas Patocka
2020-06-16 17:43 ` [dm-devel] " Eric Biggers
2020-06-16 15:02 ` [PATCH 4/4] crypto: fix the drivers that don't respect CRYPTO_TFM_REQ_MAY_SLEEP Mikulas Patocka
2020-06-16 17:50 ` [dm-devel] " Eric Biggers
2020-06-16 18:18 ` Mikulas Patocka
2020-06-16 18:23 ` Eric Biggers
2020-06-17 13:46 ` Mikulas Patocka
2020-06-17 13:48 ` [PATCH 1/2] cpt-crypto: don't sleep of CRYPTO_TFM_REQ_MAY_SLEEP was not specified Mikulas Patocka
2020-06-26 6:07 ` Herbert Xu
2020-06-17 13:49 ` [PATCH 2/2] hisilicon-crypto: " Mikulas Patocka
2020-06-17 14:11 ` [dm-devel] " Jonathan Cameron
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=alpine.LRH.2.02.2006161101080.28052@file01.intranet.prod.int.rdu2.redhat.com \
--to=mpatocka@redhat.com \
--cc=davem@davemloft.net \
--cc=dm-devel@redhat.com \
--cc=herbert@gondor.apana.org.au \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mbroz@redhat.com \
--cc=msnitzer@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).