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Patch "libceph: introduce ceph_crypt() for in-place en/decryption" has been added to the 4.9-stable tree

PATCH [email protected] 2 participants 11 messages Jan 20, 2017 – Jan 23, 2017

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#0 lore raw

This is a note to let you know that I've just added the patch titled

libceph: introduce ceph_crypt() for in-place en/decryption

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From a45f795c65b479b4ba107b6ccde29b896d51ee98 Mon Sep 17 00:00:00 2001

From: Ilya Dryomov <[email protected]>
Date: Fri, 2 Dec 2016 16:35:07 +0100
Subject: libceph: introduce ceph_crypt() for in-place en/decryption

From: Ilya Dryomov <[email protected]>

commit a45f795c65b479b4ba107b6ccde29b896d51ee98 upstream.

Starting with 4.9, kernel stacks may be vmalloced and therefore not guaranteed to be physically contiguous; the new CONFIG_VMAP_STACK option is enabled by default on x86. This makes it invalid to use on-stack buffers with the crypto scatterlist API, as sg_set_buf() expects a logical address and won't work with vmalloced addresses.

There isn't a different (e.g. kvec-based) crypto API we could switch net/ceph/crypto.c to and the current scatterlist.h API isn't getting updated to accommodate this use case. Allocating a new header and padding for each operation is a non-starter, so do the en/decryption in-place on a single pre-assembled (header + data + padding) heap buffer. This is explicitly supported by the crypto API:

"... the caller may provide the same scatter/gather list for the
plaintext and cipher text. After the completion of the cipher operation, the plaintext data is replaced with the ciphertext data in case of an encryption and vice versa for a decryption."

---
 net/ceph/crypto.c |   87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 net/ceph/crypto.h |    2 +
 2 files changed, 89 insertions(+)
net/ceph/crypto.c +87 -0
@@ -526,6 +526,93 @@ int ceph_encrypt2(struct ceph_crypto_key
 	}
 }
 
+static int ceph_aes_crypt(const struct ceph_crypto_key *key, bool encrypt,
+			  void *buf, int buf_len, int in_len, int *pout_len)
+{
+	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
+	SKCIPHER_REQUEST_ON_STACK(req, tfm);
+	struct sg_table sgt;
+	struct scatterlist prealloc_sg;
+	char iv[AES_BLOCK_SIZE];
+	int pad_byte = AES_BLOCK_SIZE - (in_len & (AES_BLOCK_SIZE - 1));
+	int crypt_len = encrypt ? in_len + pad_byte : in_len;
+	int ret;
+
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	WARN_ON(crypt_len > buf_len);
+	if (encrypt)
+		memset(buf + in_len, pad_byte, pad_byte);
+	ret = setup_sgtable(&sgt, &prealloc_sg, buf, crypt_len);
+	if (ret)
+		goto out_tfm;
+
+	crypto_skcipher_setkey((void *)tfm, key->key, key->len);
+	memcpy(iv, aes_iv, AES_BLOCK_SIZE);
+
+	skcipher_request_set_tfm(req, tfm);
+	skcipher_request_set_callback(req, 0, NULL, NULL);
+	skcipher_request_set_crypt(req, sgt.sgl, sgt.sgl, crypt_len, iv);
+
+	/*
+	print_hex_dump(KERN_ERR, "key: ", DUMP_PREFIX_NONE, 16, 1,
+		       key->key, key->len, 1);
+	print_hex_dump(KERN_ERR, " in: ", DUMP_PREFIX_NONE, 16, 1,
+		       buf, crypt_len, 1);
+	*/
+	if (encrypt)
+		ret = crypto_skcipher_encrypt(req);
+	else
+		ret = crypto_skcipher_decrypt(req);
+	skcipher_request_zero(req);
+	if (ret) {
+		pr_err("%s %scrypt failed: %d\n", __func__,
+		       encrypt ? "en" : "de", ret);
+		goto out_sgt;
+	}
+	/*
+	print_hex_dump(KERN_ERR, "out: ", DUMP_PREFIX_NONE, 16, 1,
+		       buf, crypt_len, 1);
+	*/
+
+	if (encrypt) {
+		*pout_len = crypt_len;
+	} else {
+		pad_byte = *(char *)(buf + in_len - 1);
+		if (pad_byte > 0 && pad_byte <= AES_BLOCK_SIZE &&
+		    in_len >= pad_byte) {
+			*pout_len = in_len - pad_byte;
+		} else {
+			pr_err("%s got bad padding %d on in_len %d\n",
+			       __func__, pad_byte, in_len);
+			ret = -EPERM;
+			goto out_sgt;
+		}
+	}
+
+out_sgt:
+	teardown_sgtable(&sgt);
+out_tfm:
+	crypto_free_skcipher(tfm);
+	return ret;
+}
+
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+	       void *buf, int buf_len, int in_len, int *pout_len)
+{
+	switch (key->type) {
+	case CEPH_CRYPTO_NONE:
+		*pout_len = in_len;
+		return 0;
+	case CEPH_CRYPTO_AES:
+		return ceph_aes_crypt(key, encrypt, buf, buf_len, in_len,
+				      pout_len);
+	default:
+		return -ENOTSUPP;
+	}
+}
+
 static int ceph_key_preparse(struct key_preparsed_payload *prep)
 {
 	struct ceph_crypto_key *ckey;
net/ceph/crypto.h +2 -0
@@ -43,6 +43,8 @@ int ceph_encrypt2(struct ceph_crypto_key
 		  void *dst, size_t *dst_len,
 		  const void *src1, size_t src1_len,
 		  const void *src2, size_t src2_len);
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+	       void *buf, int buf_len, int in_len, int *pout_len);
 int ceph_crypto_init(void);
 void ceph_crypto_shutdown(void);
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch

maintainer
#1 lore raw
Quoted 162 lines · On Fri, Jan 20, 2017 at 3:53 PM, <[email protected]> wrote:

This is a note to let you know that I've just added the patch titled

libceph: introduce ceph_crypt() for in-place en/decryption

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From a45f795c65b479b4ba107b6ccde29b896d51ee98 Mon Sep 17 00:00:00 2001
From: Ilya Dryomov <[email protected]>
Date: Fri, 2 Dec 2016 16:35:07 +0100
Subject: libceph: introduce ceph_crypt() for in-place en/decryption

From: Ilya Dryomov <[email protected]>

commit a45f795c65b479b4ba107b6ccde29b896d51ee98 upstream.

Starting with 4.9, kernel stacks may be vmalloced and therefore not guaranteed to be physically contiguous; the new CONFIG_VMAP_STACK option is enabled by default on x86. This makes it invalid to use on-stack buffers with the crypto scatterlist API, as sg_set_buf() expects a logical address and won't work with vmalloced addresses.

There isn't a different (e.g. kvec-based) crypto API we could switch net/ceph/crypto.c to and the current scatterlist.h API isn't getting updated to accommodate this use case. Allocating a new header and padding for each operation is a non-starter, so do the en/decryption in-place on a single pre-assembled (header + data + padding) heap buffer. This is explicitly supported by the crypto API:

"... the caller may provide the same scatter/gather list for the
plaintext and cipher text. After the completion of the cipher operation, the plaintext data is replaced with the ciphertext data in case of an encryption and vice versa for a decryption."

---
 net/ceph/crypto.c |   87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 net/ceph/crypto.h |    2 +
 2 files changed, 89 insertions(+)
net/ceph/crypto.c +87 -0
@@ -526,6 +526,93 @@ int ceph_encrypt2(struct ceph_crypto_key
        }
 }
 
+static int ceph_aes_crypt(const struct ceph_crypto_key *key, bool encrypt,
+                         void *buf, int buf_len, int in_len, int *pout_len)
+{
+       struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
+       SKCIPHER_REQUEST_ON_STACK(req, tfm);
+       struct sg_table sgt;
+       struct scatterlist prealloc_sg;
+       char iv[AES_BLOCK_SIZE];
+       int pad_byte = AES_BLOCK_SIZE - (in_len & (AES_BLOCK_SIZE - 1));
+       int crypt_len = encrypt ? in_len + pad_byte : in_len;
+       int ret;
+
+       if (IS_ERR(tfm))
+               return PTR_ERR(tfm);
+
+       WARN_ON(crypt_len > buf_len);
+       if (encrypt)
+               memset(buf + in_len, pad_byte, pad_byte);
+       ret = setup_sgtable(&sgt, &prealloc_sg, buf, crypt_len);
+       if (ret)
+               goto out_tfm;
+
+       crypto_skcipher_setkey((void *)tfm, key->key, key->len);
+       memcpy(iv, aes_iv, AES_BLOCK_SIZE);
+
+       skcipher_request_set_tfm(req, tfm);
+       skcipher_request_set_callback(req, 0, NULL, NULL);
+       skcipher_request_set_crypt(req, sgt.sgl, sgt.sgl, crypt_len, iv);
+
+       /*
+       print_hex_dump(KERN_ERR, "key: ", DUMP_PREFIX_NONE, 16, 1,
+                      key->key, key->len, 1);
+       print_hex_dump(KERN_ERR, " in: ", DUMP_PREFIX_NONE, 16, 1,
+                      buf, crypt_len, 1);
+       */
+       if (encrypt)
+               ret = crypto_skcipher_encrypt(req);
+       else
+               ret = crypto_skcipher_decrypt(req);
+       skcipher_request_zero(req);
+       if (ret) {
+               pr_err("%s %scrypt failed: %d\n", __func__,
+                      encrypt ? "en" : "de", ret);
+               goto out_sgt;
+       }
+       /*
+       print_hex_dump(KERN_ERR, "out: ", DUMP_PREFIX_NONE, 16, 1,
+                      buf, crypt_len, 1);
+       */
+
+       if (encrypt) {
+               *pout_len = crypt_len;
+       } else {
+               pad_byte = *(char *)(buf + in_len - 1);
+               if (pad_byte > 0 && pad_byte <= AES_BLOCK_SIZE &&
+                   in_len >= pad_byte) {
+                       *pout_len = in_len - pad_byte;
+               } else {
+                       pr_err("%s got bad padding %d on in_len %d\n",
+                              __func__, pad_byte, in_len);
+                       ret = -EPERM;
+                       goto out_sgt;
+               }
+       }
+
+out_sgt:
+       teardown_sgtable(&sgt);
+out_tfm:
+       crypto_free_skcipher(tfm);
+       return ret;
+}
+
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+              void *buf, int buf_len, int in_len, int *pout_len)
+{
+       switch (key->type) {
+       case CEPH_CRYPTO_NONE:
+               *pout_len = in_len;
+               return 0;
+       case CEPH_CRYPTO_AES:
+               return ceph_aes_crypt(key, encrypt, buf, buf_len, in_len,
+                                     pout_len);
+       default:
+               return -ENOTSUPP;
+       }
+}
+
 static int ceph_key_preparse(struct key_preparsed_payload *prep)
 {
        struct ceph_crypto_key *ckey;
net/ceph/crypto.h +2 -0
@@ -43,6 +43,8 @@ int ceph_encrypt2(struct ceph_crypto_key
                  void *dst, size_t *dst_len,
                  const void *src1, size_t src1_len,
                  const void *src2, size_t src2_len);
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+              void *buf, int buf_len, int in_len, int *pout_len);
 int ceph_crypto_init(void);
 void ceph_crypto_shutdown(void);
 
Quoted 3 lines

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch

Hi Greg,

Taking this commit by itself without the surrounding commits (altogether about a dozen) doesn't make any sense. It wasn't marked for stable in any way and shouldn't be included.

Thanks,

Ilya

author maintainer
#2 lore raw
Quoted 165 lines · Ilya Dryomov
Quoted 164 lines · On Fri, Jan 20, 2017 at 3:53 PM, <[email protected]> wrote:

This is a note to let you know that I've just added the patch titled

libceph: introduce ceph_crypt() for in-place en/decryption

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From a45f795c65b479b4ba107b6ccde29b896d51ee98 Mon Sep 17 00:00:00 2001
From: Ilya Dryomov <[email protected]>
Date: Fri, 2 Dec 2016 16:35:07 +0100
Subject: libceph: introduce ceph_crypt() for in-place en/decryption

From: Ilya Dryomov <[email protected]>

commit a45f795c65b479b4ba107b6ccde29b896d51ee98 upstream.

Starting with 4.9, kernel stacks may be vmalloced and therefore not guaranteed to be physically contiguous; the new CONFIG_VMAP_STACK option is enabled by default on x86. This makes it invalid to use on-stack buffers with the crypto scatterlist API, as sg_set_buf() expects a logical address and won't work with vmalloced addresses.

There isn't a different (e.g. kvec-based) crypto API we could switch net/ceph/crypto.c to and the current scatterlist.h API isn't getting updated to accommodate this use case. Allocating a new header and padding for each operation is a non-starter, so do the en/decryption in-place on a single pre-assembled (header + data + padding) heap buffer. This is explicitly supported by the crypto API:

"... the caller may provide the same scatter/gather list for the
plaintext and cipher text. After the completion of the cipher operation, the plaintext data is replaced with the ciphertext data in case of an encryption and vice versa for a decryption."

---
 net/ceph/crypto.c |   87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 net/ceph/crypto.h |    2 +
 2 files changed, 89 insertions(+)
net/ceph/crypto.c +87 -0
@@ -526,6 +526,93 @@ int ceph_encrypt2(struct ceph_crypto_key
        }
 }
 
+static int ceph_aes_crypt(const struct ceph_crypto_key *key, bool encrypt,
+                         void *buf, int buf_len, int in_len, int *pout_len)
+{
+       struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
+       SKCIPHER_REQUEST_ON_STACK(req, tfm);
+       struct sg_table sgt;
+       struct scatterlist prealloc_sg;
+       char iv[AES_BLOCK_SIZE];
+       int pad_byte = AES_BLOCK_SIZE - (in_len & (AES_BLOCK_SIZE - 1));
+       int crypt_len = encrypt ? in_len + pad_byte : in_len;
+       int ret;
+
+       if (IS_ERR(tfm))
+               return PTR_ERR(tfm);
+
+       WARN_ON(crypt_len > buf_len);
+       if (encrypt)
+               memset(buf + in_len, pad_byte, pad_byte);
+       ret = setup_sgtable(&sgt, &prealloc_sg, buf, crypt_len);
+       if (ret)
+               goto out_tfm;
+
+       crypto_skcipher_setkey((void *)tfm, key->key, key->len);
+       memcpy(iv, aes_iv, AES_BLOCK_SIZE);
+
+       skcipher_request_set_tfm(req, tfm);
+       skcipher_request_set_callback(req, 0, NULL, NULL);
+       skcipher_request_set_crypt(req, sgt.sgl, sgt.sgl, crypt_len, iv);
+
+       /*
+       print_hex_dump(KERN_ERR, "key: ", DUMP_PREFIX_NONE, 16, 1,
+                      key->key, key->len, 1);
+       print_hex_dump(KERN_ERR, " in: ", DUMP_PREFIX_NONE, 16, 1,
+                      buf, crypt_len, 1);
+       */
+       if (encrypt)
+               ret = crypto_skcipher_encrypt(req);
+       else
+               ret = crypto_skcipher_decrypt(req);
+       skcipher_request_zero(req);
+       if (ret) {
+               pr_err("%s %scrypt failed: %d\n", __func__,
+                      encrypt ? "en" : "de", ret);
+               goto out_sgt;
+       }
+       /*
+       print_hex_dump(KERN_ERR, "out: ", DUMP_PREFIX_NONE, 16, 1,
+                      buf, crypt_len, 1);
+       */
+
+       if (encrypt) {
+               *pout_len = crypt_len;
+       } else {
+               pad_byte = *(char *)(buf + in_len - 1);
+               if (pad_byte > 0 && pad_byte <= AES_BLOCK_SIZE &&
+                   in_len >= pad_byte) {
+                       *pout_len = in_len - pad_byte;
+               } else {
+                       pr_err("%s got bad padding %d on in_len %d\n",
+                              __func__, pad_byte, in_len);
+                       ret = -EPERM;
+                       goto out_sgt;
+               }
+       }
+
+out_sgt:
+       teardown_sgtable(&sgt);
+out_tfm:
+       crypto_free_skcipher(tfm);
+       return ret;
+}
+
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+              void *buf, int buf_len, int in_len, int *pout_len)
+{
+       switch (key->type) {
+       case CEPH_CRYPTO_NONE:
+               *pout_len = in_len;
+               return 0;
+       case CEPH_CRYPTO_AES:
+               return ceph_aes_crypt(key, encrypt, buf, buf_len, in_len,
+                                     pout_len);
+       default:
+               return -ENOTSUPP;
+       }
+}
+
 static int ceph_key_preparse(struct key_preparsed_payload *prep)
 {
        struct ceph_crypto_key *ckey;
net/ceph/crypto.h +2 -0
@@ -43,6 +43,8 @@ int ceph_encrypt2(struct ceph_crypto_key
                  void *dst, size_t *dst_len,
                  const void *src1, size_t src1_len,
                  const void *src2, size_t src2_len);
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+              void *buf, int buf_len, int in_len, int *pout_len);
 int ceph_crypto_init(void);
 void ceph_crypto_shutdown(void);
 

Patches currently in stable-queue which might be from [email protected] are

Quoted 7 lines
Quoted 1 line

queue-4.9/libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch

Hi Greg,

Taking this commit by itself without the surrounding commits (altogether about a dozen) doesn't make any sense. It wasn't marked for stable in any way and shouldn't be included.

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

thanks,

greg k-h

author maintainer
#3 lore raw
Quoted 170 lines · Greg KH
Quoted 169 lines · Ilya Dryomov
Quoted 162 lines · On Fri, Jan 20, 2017 at 3:53 PM, <[email protected]> wrote:

This is a note to let you know that I've just added the patch titled

libceph: introduce ceph_crypt() for in-place en/decryption

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From a45f795c65b479b4ba107b6ccde29b896d51ee98 Mon Sep 17 00:00:00 2001
From: Ilya Dryomov <[email protected]>
Date: Fri, 2 Dec 2016 16:35:07 +0100
Subject: libceph: introduce ceph_crypt() for in-place en/decryption

From: Ilya Dryomov <[email protected]>

commit a45f795c65b479b4ba107b6ccde29b896d51ee98 upstream.

Starting with 4.9, kernel stacks may be vmalloced and therefore not guaranteed to be physically contiguous; the new CONFIG_VMAP_STACK option is enabled by default on x86. This makes it invalid to use on-stack buffers with the crypto scatterlist API, as sg_set_buf() expects a logical address and won't work with vmalloced addresses.

There isn't a different (e.g. kvec-based) crypto API we could switch net/ceph/crypto.c to and the current scatterlist.h API isn't getting updated to accommodate this use case. Allocating a new header and padding for each operation is a non-starter, so do the en/decryption in-place on a single pre-assembled (header + data + padding) heap buffer. This is explicitly supported by the crypto API:

"... the caller may provide the same scatter/gather list for the
plaintext and cipher text. After the completion of the cipher operation, the plaintext data is replaced with the ciphertext data in case of an encryption and vice versa for a decryption."

---
 net/ceph/crypto.c |   87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 net/ceph/crypto.h |    2 +
 2 files changed, 89 insertions(+)
net/ceph/crypto.c +87 -0
@@ -526,6 +526,93 @@ int ceph_encrypt2(struct ceph_crypto_key
        }
 }
 
+static int ceph_aes_crypt(const struct ceph_crypto_key *key, bool encrypt,
+                         void *buf, int buf_len, int in_len, int *pout_len)
+{
+       struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
+       SKCIPHER_REQUEST_ON_STACK(req, tfm);
+       struct sg_table sgt;
+       struct scatterlist prealloc_sg;
+       char iv[AES_BLOCK_SIZE];
+       int pad_byte = AES_BLOCK_SIZE - (in_len & (AES_BLOCK_SIZE - 1));
+       int crypt_len = encrypt ? in_len + pad_byte : in_len;
+       int ret;
+
+       if (IS_ERR(tfm))
+               return PTR_ERR(tfm);
+
+       WARN_ON(crypt_len > buf_len);
+       if (encrypt)
+               memset(buf + in_len, pad_byte, pad_byte);
+       ret = setup_sgtable(&sgt, &prealloc_sg, buf, crypt_len);
+       if (ret)
+               goto out_tfm;
+
+       crypto_skcipher_setkey((void *)tfm, key->key, key->len);
+       memcpy(iv, aes_iv, AES_BLOCK_SIZE);
+
+       skcipher_request_set_tfm(req, tfm);
+       skcipher_request_set_callback(req, 0, NULL, NULL);
+       skcipher_request_set_crypt(req, sgt.sgl, sgt.sgl, crypt_len, iv);
+
+       /*
+       print_hex_dump(KERN_ERR, "key: ", DUMP_PREFIX_NONE, 16, 1,
+                      key->key, key->len, 1);
+       print_hex_dump(KERN_ERR, " in: ", DUMP_PREFIX_NONE, 16, 1,
+                      buf, crypt_len, 1);
+       */
+       if (encrypt)
+               ret = crypto_skcipher_encrypt(req);
+       else
+               ret = crypto_skcipher_decrypt(req);
+       skcipher_request_zero(req);
+       if (ret) {
+               pr_err("%s %scrypt failed: %d\n", __func__,
+                      encrypt ? "en" : "de", ret);
+               goto out_sgt;
+       }
+       /*
+       print_hex_dump(KERN_ERR, "out: ", DUMP_PREFIX_NONE, 16, 1,
+                      buf, crypt_len, 1);
+       */
+
+       if (encrypt) {
+               *pout_len = crypt_len;
+       } else {
+               pad_byte = *(char *)(buf + in_len - 1);
+               if (pad_byte > 0 && pad_byte <= AES_BLOCK_SIZE &&
+                   in_len >= pad_byte) {
+                       *pout_len = in_len - pad_byte;
+               } else {
+                       pr_err("%s got bad padding %d on in_len %d\n",
+                              __func__, pad_byte, in_len);
+                       ret = -EPERM;
+                       goto out_sgt;
+               }
+       }
+
+out_sgt:
+       teardown_sgtable(&sgt);
+out_tfm:
+       crypto_free_skcipher(tfm);
+       return ret;
+}
+
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+              void *buf, int buf_len, int in_len, int *pout_len)
+{
+       switch (key->type) {
+       case CEPH_CRYPTO_NONE:
+               *pout_len = in_len;
+               return 0;
+       case CEPH_CRYPTO_AES:
+               return ceph_aes_crypt(key, encrypt, buf, buf_len, in_len,
+                                     pout_len);
+       default:
+               return -ENOTSUPP;
+       }
+}
+
 static int ceph_key_preparse(struct key_preparsed_payload *prep)
 {
        struct ceph_crypto_key *ckey;
net/ceph/crypto.h +2 -0
@@ -43,6 +43,8 @@ int ceph_encrypt2(struct ceph_crypto_key
                  void *dst, size_t *dst_len,
                  const void *src1, size_t src1_len,
                  const void *src2, size_t src2_len);
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+              void *buf, int buf_len, int in_len, int *pout_len);
 int ceph_crypto_init(void);
 void ceph_crypto_shutdown(void);
 
Quoted 3 lines

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch

Hi Greg,

Quoted 7 lines
Quoted 3 lines

Taking this commit by itself without the surrounding commits (altogether about a dozen) doesn't make any sense. It wasn't marked for stable in any way and shouldn't be included.

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

And yes, you are correct in that this doesn't do anything on it's own, I haven't made it through my patches today, I shouldn't have pushed this one until the rest of the tree was done, sorry about that.

greg k-h

maintainer
#4 lore raw
In reply to Greg KH
Quoted 170 lines · Greg KH
Quoted 169 lines · Ilya Dryomov
Quoted 162 lines · On Fri, Jan 20, 2017 at 3:53 PM, <[email protected]> wrote:

This is a note to let you know that I've just added the patch titled

libceph: introduce ceph_crypt() for in-place en/decryption

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From a45f795c65b479b4ba107b6ccde29b896d51ee98 Mon Sep 17 00:00:00 2001
From: Ilya Dryomov <[email protected]>
Date: Fri, 2 Dec 2016 16:35:07 +0100
Subject: libceph: introduce ceph_crypt() for in-place en/decryption

From: Ilya Dryomov <[email protected]>

commit a45f795c65b479b4ba107b6ccde29b896d51ee98 upstream.

Starting with 4.9, kernel stacks may be vmalloced and therefore not guaranteed to be physically contiguous; the new CONFIG_VMAP_STACK option is enabled by default on x86. This makes it invalid to use on-stack buffers with the crypto scatterlist API, as sg_set_buf() expects a logical address and won't work with vmalloced addresses.

There isn't a different (e.g. kvec-based) crypto API we could switch net/ceph/crypto.c to and the current scatterlist.h API isn't getting updated to accommodate this use case. Allocating a new header and padding for each operation is a non-starter, so do the en/decryption in-place on a single pre-assembled (header + data + padding) heap buffer. This is explicitly supported by the crypto API:

"... the caller may provide the same scatter/gather list for the
plaintext and cipher text. After the completion of the cipher operation, the plaintext data is replaced with the ciphertext data in case of an encryption and vice versa for a decryption."

---
 net/ceph/crypto.c |   87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 net/ceph/crypto.h |    2 +
 2 files changed, 89 insertions(+)
net/ceph/crypto.c +87 -0
@@ -526,6 +526,93 @@ int ceph_encrypt2(struct ceph_crypto_key
        }
 }
 
+static int ceph_aes_crypt(const struct ceph_crypto_key *key, bool encrypt,
+                         void *buf, int buf_len, int in_len, int *pout_len)
+{
+       struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
+       SKCIPHER_REQUEST_ON_STACK(req, tfm);
+       struct sg_table sgt;
+       struct scatterlist prealloc_sg;
+       char iv[AES_BLOCK_SIZE];
+       int pad_byte = AES_BLOCK_SIZE - (in_len & (AES_BLOCK_SIZE - 1));
+       int crypt_len = encrypt ? in_len + pad_byte : in_len;
+       int ret;
+
+       if (IS_ERR(tfm))
+               return PTR_ERR(tfm);
+
+       WARN_ON(crypt_len > buf_len);
+       if (encrypt)
+               memset(buf + in_len, pad_byte, pad_byte);
+       ret = setup_sgtable(&sgt, &prealloc_sg, buf, crypt_len);
+       if (ret)
+               goto out_tfm;
+
+       crypto_skcipher_setkey((void *)tfm, key->key, key->len);
+       memcpy(iv, aes_iv, AES_BLOCK_SIZE);
+
+       skcipher_request_set_tfm(req, tfm);
+       skcipher_request_set_callback(req, 0, NULL, NULL);
+       skcipher_request_set_crypt(req, sgt.sgl, sgt.sgl, crypt_len, iv);
+
+       /*
+       print_hex_dump(KERN_ERR, "key: ", DUMP_PREFIX_NONE, 16, 1,
+                      key->key, key->len, 1);
+       print_hex_dump(KERN_ERR, " in: ", DUMP_PREFIX_NONE, 16, 1,
+                      buf, crypt_len, 1);
+       */
+       if (encrypt)
+               ret = crypto_skcipher_encrypt(req);
+       else
+               ret = crypto_skcipher_decrypt(req);
+       skcipher_request_zero(req);
+       if (ret) {
+               pr_err("%s %scrypt failed: %d\n", __func__,
+                      encrypt ? "en" : "de", ret);
+               goto out_sgt;
+       }
+       /*
+       print_hex_dump(KERN_ERR, "out: ", DUMP_PREFIX_NONE, 16, 1,
+                      buf, crypt_len, 1);
+       */
+
+       if (encrypt) {
+               *pout_len = crypt_len;
+       } else {
+               pad_byte = *(char *)(buf + in_len - 1);
+               if (pad_byte > 0 && pad_byte <= AES_BLOCK_SIZE &&
+                   in_len >= pad_byte) {
+                       *pout_len = in_len - pad_byte;
+               } else {
+                       pr_err("%s got bad padding %d on in_len %d\n",
+                              __func__, pad_byte, in_len);
+                       ret = -EPERM;
+                       goto out_sgt;
+               }
+       }
+
+out_sgt:
+       teardown_sgtable(&sgt);
+out_tfm:
+       crypto_free_skcipher(tfm);
+       return ret;
+}
+
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+              void *buf, int buf_len, int in_len, int *pout_len)
+{
+       switch (key->type) {
+       case CEPH_CRYPTO_NONE:
+               *pout_len = in_len;
+               return 0;
+       case CEPH_CRYPTO_AES:
+               return ceph_aes_crypt(key, encrypt, buf, buf_len, in_len,
+                                     pout_len);
+       default:
+               return -ENOTSUPP;
+       }
+}
+
 static int ceph_key_preparse(struct key_preparsed_payload *prep)
 {
        struct ceph_crypto_key *ckey;
net/ceph/crypto.h +2 -0
@@ -43,6 +43,8 @@ int ceph_encrypt2(struct ceph_crypto_key
                  void *dst, size_t *dst_len,
                  const void *src1, size_t src1_len,
                  const void *src2, size_t src2_len);
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+              void *buf, int buf_len, int in_len, int *pout_len);
 int ceph_crypto_init(void);
 void ceph_crypto_shutdown(void);
 
Quoted 3 lines

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch

Hi Greg,

Quoted 7 lines
Quoted 3 lines

Taking this commit by itself without the surrounding commits (altogether about a dozen) doesn't make any sense. It wasn't marked for stable in any way and shouldn't be included.

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

Yes, but it's pretty large in terms of diffstat. Honestly, I'm not worried -- our on-stack buffers are really small and the chances that any of them will straddle a page should be tiny.

Here is the list (bottom to top):

2b1e1a7cd0a6 libceph: remove now unused ceph_*{en,de}crypt*() functions e15fd0a11db0 libceph: switch ceph_x_decrypt() to ceph_crypt() d03857c63bb0 libceph: switch ceph_x_encrypt() to ceph_crypt() 4eb4517ce7c9 libceph: tweak calcu_signature() a little 7882a26d2e2e libceph: rename and align ceph_x_authorizer::reply_buf a45f795c65b4 libceph: introduce ceph_crypt() for in-place en/decryption 55d9cc834f93 libceph: introduce ceph_x_encrypt_offset() 462e650451c5 libceph: old_key in process_one_ticket() is redundant 36721ece1e84 libceph: ceph_x_encrypt_buflen() takes in_len

Can probably drop one or two, but you want to take these, I'd rather you take them all.

Thanks,

Ilya

author maintainer
#5 lore raw
Quoted 21 lines · Ilya Dryomov
Quoted 3 lines · Greg KH

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

Yes, but it's pretty large in terms of diffstat. Honestly, I'm not worried -- our on-stack buffers are really small and the chances that any of them will straddle a page should be tiny.

Here is the list (bottom to top):

2b1e1a7cd0a6 libceph: remove now unused ceph_*{en,de}crypt*() functions e15fd0a11db0 libceph: switch ceph_x_decrypt() to ceph_crypt() d03857c63bb0 libceph: switch ceph_x_encrypt() to ceph_crypt() 4eb4517ce7c9 libceph: tweak calcu_signature() a little 7882a26d2e2e libceph: rename and align ceph_x_authorizer::reply_buf a45f795c65b4 libceph: introduce ceph_crypt() for in-place en/decryption 55d9cc834f93 libceph: introduce ceph_x_encrypt_offset() 462e650451c5 libceph: old_key in process_one_ticket() is redundant 36721ece1e84 libceph: ceph_x_encrypt_buflen() takes in_len

Quoted 2 lines

Can probably drop one or two, but you want to take these, I'd rather you take them all.

Given the length that 4.9 is going to be around, I'd prefer to have this work correctly. I'll drop this single patch now, but will queue this larger list up later when I get a chance to do more testing and review.

Brad, thanks again for pointing this issue out, much appreciated for the heads up, I had missed this one in my review.

thanks,

greg k-h

maintainer
#6 lore raw
Quoted 22 lines · Greg KH
Quoted 21 lines · Ilya Dryomov
Quoted 3 lines · Greg KH

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

Yes, but it's pretty large in terms of diffstat. Honestly, I'm not worried -- our on-stack buffers are really small and the chances that any of them will straddle a page should be tiny.

Here is the list (bottom to top):

2b1e1a7cd0a6 libceph: remove now unused ceph_*{en,de}crypt*() functions e15fd0a11db0 libceph: switch ceph_x_decrypt() to ceph_crypt() d03857c63bb0 libceph: switch ceph_x_encrypt() to ceph_crypt() 4eb4517ce7c9 libceph: tweak calcu_signature() a little 7882a26d2e2e libceph: rename and align ceph_x_authorizer::reply_buf a45f795c65b4 libceph: introduce ceph_crypt() for in-place en/decryption 55d9cc834f93 libceph: introduce ceph_x_encrypt_offset() 462e650451c5 libceph: old_key in process_one_ticket() is redundant 36721ece1e84 libceph: ceph_x_encrypt_buflen() takes in_len

Quoted 6 lines
Quoted 2 lines

Can probably drop one or two, but you want to take these, I'd rather you take them all.

Given the length that 4.9 is going to be around, I'd prefer to have this work correctly. I'll drop this single patch now, but will queue this larger list up later when I get a chance to do more testing and review.

Any chance you can also take

7af3ea189a9a libceph: stop allocating a new cipher on every crypto request 6db2304aabb0 libceph: uninline ceph_crypto_key_destroy()

to make 4.9.z even more awesome? ;)

These depend on the ceph_crypt() bunch and fix a writeback deadlock that has been there forever but started showing up only recently. The only reason I didn't mark it for stable was this dependency.

All of the above patches were developed and tested on 4.9, so there shouldn't be any issues.

Thanks,

Ilya

author maintainer
#7 lore raw
Quoted 35 lines · Ilya Dryomov
Quoted 22 lines · Greg KH
Quoted 21 lines · Ilya Dryomov
Quoted 3 lines · Greg KH

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

Yes, but it's pretty large in terms of diffstat. Honestly, I'm not worried -- our on-stack buffers are really small and the chances that any of them will straddle a page should be tiny.

Here is the list (bottom to top):

2b1e1a7cd0a6 libceph: remove now unused ceph_*{en,de}crypt*() functions e15fd0a11db0 libceph: switch ceph_x_decrypt() to ceph_crypt() d03857c63bb0 libceph: switch ceph_x_encrypt() to ceph_crypt() 4eb4517ce7c9 libceph: tweak calcu_signature() a little 7882a26d2e2e libceph: rename and align ceph_x_authorizer::reply_buf a45f795c65b4 libceph: introduce ceph_crypt() for in-place en/decryption 55d9cc834f93 libceph: introduce ceph_x_encrypt_offset() 462e650451c5 libceph: old_key in process_one_ticket() is redundant 36721ece1e84 libceph: ceph_x_encrypt_buflen() takes in_len

Quoted 6 lines
Quoted 2 lines

Can probably drop one or two, but you want to take these, I'd rather you take them all.

Given the length that 4.9 is going to be around, I'd prefer to have this work correctly. I'll drop this single patch now, but will queue this larger list up later when I get a chance to do more testing and review.

Any chance you can also take

7af3ea189a9a libceph: stop allocating a new cipher on every crypto request 6db2304aabb0 libceph: uninline ceph_crypto_key_destroy()

Quoted 8 lines

to make 4.9.z even more awesome? ;)

These depend on the ceph_crypt() bunch and fix a writeback deadlock that has been there forever but started showing up only recently. The only reason I didn't mark it for stable was this dependency.

All of the above patches were developed and tested on 4.9, so there shouldn't be any issues.

Sure, I'll work to queue these all up for the next round of kernels, thanks for the git commit ids.

greg k-h

author maintainer
#8 lore raw
Quoted 42 lines · Greg KH
Quoted 41 lines · Ilya Dryomov
Quoted 22 lines · Greg KH
Quoted 21 lines · Ilya Dryomov
Quoted 3 lines · Greg KH

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

Yes, but it's pretty large in terms of diffstat. Honestly, I'm not worried -- our on-stack buffers are really small and the chances that any of them will straddle a page should be tiny.

Here is the list (bottom to top):

2b1e1a7cd0a6 libceph: remove now unused ceph_*{en,de}crypt*() functions e15fd0a11db0 libceph: switch ceph_x_decrypt() to ceph_crypt() d03857c63bb0 libceph: switch ceph_x_encrypt() to ceph_crypt() 4eb4517ce7c9 libceph: tweak calcu_signature() a little 7882a26d2e2e libceph: rename and align ceph_x_authorizer::reply_buf a45f795c65b4 libceph: introduce ceph_crypt() for in-place en/decryption 55d9cc834f93 libceph: introduce ceph_x_encrypt_offset() 462e650451c5 libceph: old_key in process_one_ticket() is redundant 36721ece1e84 libceph: ceph_x_encrypt_buflen() takes in_len

Quoted 6 lines
Quoted 2 lines

Can probably drop one or two, but you want to take these, I'd rather you take them all.

Given the length that 4.9 is going to be around, I'd prefer to have this work correctly. I'll drop this single patch now, but will queue this larger list up later when I get a chance to do more testing and review.

Any chance you can also take

7af3ea189a9a libceph: stop allocating a new cipher on every crypto request 6db2304aabb0 libceph: uninline ceph_crypto_key_destroy()

to make 4.9.z even more awesome? ;)

These depend on the ceph_crypt() bunch and fix a writeback deadlock that has been there forever but started showing up only recently. The only reason I didn't mark it for stable was this dependency.

Quoted 5 lines
Quoted 2 lines

All of the above patches were developed and tested on 4.9, so there shouldn't be any issues.

Sure, I'll work to queue these all up for the next round of kernels, thanks for the git commit ids.

Ok, I've queued these all up, along with a few other minor ones I found when digging through the logs. If any of them look incorrect, please let me know.

thanks,

greg k-h

maintainer
#9 lore raw
Quoted 46 lines · Greg KH
Quoted 45 lines · Greg KH
Quoted 43 lines · Ilya Dryomov
Quoted 22 lines · Greg KH
Quoted 21 lines · Ilya Dryomov
Quoted 3 lines · Greg KH

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

Yes, but it's pretty large in terms of diffstat. Honestly, I'm not worried -- our on-stack buffers are really small and the chances that any of them will straddle a page should be tiny.

Here is the list (bottom to top):

2b1e1a7cd0a6 libceph: remove now unused ceph_*{en,de}crypt*() functions e15fd0a11db0 libceph: switch ceph_x_decrypt() to ceph_crypt() d03857c63bb0 libceph: switch ceph_x_encrypt() to ceph_crypt() 4eb4517ce7c9 libceph: tweak calcu_signature() a little 7882a26d2e2e libceph: rename and align ceph_x_authorizer::reply_buf a45f795c65b4 libceph: introduce ceph_crypt() for in-place en/decryption 55d9cc834f93 libceph: introduce ceph_x_encrypt_offset() 462e650451c5 libceph: old_key in process_one_ticket() is redundant 36721ece1e84 libceph: ceph_x_encrypt_buflen() takes in_len

Quoted 6 lines
Quoted 2 lines

Can probably drop one or two, but you want to take these, I'd rather you take them all.

Given the length that 4.9 is going to be around, I'd prefer to have this work correctly. I'll drop this single patch now, but will queue this larger list up later when I get a chance to do more testing and review.

Any chance you can also take

7af3ea189a9a libceph: stop allocating a new cipher on every crypto request 6db2304aabb0 libceph: uninline ceph_crypto_key_destroy()

to make 4.9.z even more awesome? ;)

These depend on the ceph_crypt() bunch and fix a writeback deadlock that has been there forever but started showing up only recently. The only reason I didn't mark it for stable was this dependency.

All of the above patches were developed and tested on 4.9, so there shouldn't be any issues.

Quoted 6 lines
Quoted 2 lines

Sure, I'll work to queue these all up for the next round of kernels, thanks for the git commit ids.

Ok, I've queued these all up, along with a few other minor ones I found when digging through the logs. If any of them look incorrect, please let me know.

All 9 commits from my original list are there and look good. Not sure which are those other minor ones you are talking about, though...

Could you also add 6db2304aabb0 and 7af3ea189a9a, as discussed above?

Thanks,

Ilya

author maintainer
#10 lore raw
Quoted 50 lines · Ilya Dryomov
Quoted 49 lines · Greg KH
Quoted 47 lines · Greg KH
Quoted 35 lines · Ilya Dryomov
Quoted 22 lines · Greg KH
Quoted 21 lines · Ilya Dryomov
Quoted 3 lines · Greg KH

Ok, what were the surrounding commits? Don't we need this to handle the vmalloced stack issue in 4.9? If not, that's fine, I'll drop this, otherwise it would be good to fix that up, right?

Yes, but it's pretty large in terms of diffstat. Honestly, I'm not worried -- our on-stack buffers are really small and the chances that any of them will straddle a page should be tiny.

Here is the list (bottom to top):

2b1e1a7cd0a6 libceph: remove now unused ceph_*{en,de}crypt*() functions e15fd0a11db0 libceph: switch ceph_x_decrypt() to ceph_crypt() d03857c63bb0 libceph: switch ceph_x_encrypt() to ceph_crypt() 4eb4517ce7c9 libceph: tweak calcu_signature() a little 7882a26d2e2e libceph: rename and align ceph_x_authorizer::reply_buf a45f795c65b4 libceph: introduce ceph_crypt() for in-place en/decryption 55d9cc834f93 libceph: introduce ceph_x_encrypt_offset() 462e650451c5 libceph: old_key in process_one_ticket() is redundant 36721ece1e84 libceph: ceph_x_encrypt_buflen() takes in_len

Quoted 6 lines
Quoted 2 lines

Can probably drop one or two, but you want to take these, I'd rather you take them all.

Given the length that 4.9 is going to be around, I'd prefer to have this work correctly. I'll drop this single patch now, but will queue this larger list up later when I get a chance to do more testing and review.

Any chance you can also take

7af3ea189a9a libceph: stop allocating a new cipher on every crypto request 6db2304aabb0 libceph: uninline ceph_crypto_key_destroy()

Quoted 8 lines

to make 4.9.z even more awesome? ;)

These depend on the ceph_crypt() bunch and fix a writeback deadlock that has been there forever but started showing up only recently. The only reason I didn't mark it for stable was this dependency.

All of the above patches were developed and tested on 4.9, so there shouldn't be any issues.

Sure, I'll work to queue these all up for the next round of kernels, thanks for the git commit ids.

Quoted 6 lines
Quoted 3 lines

Ok, I've queued these all up, along with a few other minor ones I found when digging through the logs. If any of them look incorrect, please let me know.

All 9 commits from my original list are there and look good. Not sure which are those other minor ones you are talking about, though...

They should show up now, took a bit to push out.

Quoted 2 lines

Could you also add 6db2304aabb0 and 7af3ea189a9a, as discussed above?

Oops, missed that, now queued up as well, thanks.

greg k-h