FAILED: patch "[PATCH] ksmbd: validate NTLMv2 response before updating session key" failed to apply to 6.18-stable tree

FAILED: patch "[PATCH] ksmbd: validate NTLMv2 response before updating session key" failed to apply to 6.18-stable tree

[gregkh]

The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x 954d196bebb2b50151cb96454c72dc113b2af1ac
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026071427-follicle-footprint-220e@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 954d196bebb2b50151cb96454c72dc113b2af1ac Mon Sep 17 00:00:00 2001
From: Haofeng Li <lihaofeng@kylinos.cn>
Date: Tue, 23 Jun 2026 09:30:26 +0800
Subject: [PATCH] ksmbd: validate NTLMv2 response before updating session key

ksmbd_auth_ntlmv2() derives the NTLMv2 session key into
sess->sess_key before it verifies the NTLMv2 response.
ksmbd_decode_ntlmssp_auth_blob() then continues into KEY_XCH even
when ksmbd_auth_ntlmv2() failed.

With SMB3 multichannel binding, the failed authentication operates on
an existing session and the session setup error path does not expire
binding sessions. A client can send a binding session setup with a
bad NT proof and KEY_XCH and still modify sess->sess_key before
STATUS_LOGON_FAILURE is returned.

Relevant path:

  smb2_sess_setup()
    -> conn->binding = true
    -> ntlm_authenticate()
       -> session_user()
       -> ksmbd_decode_ntlmssp_auth_blob()
          -> ksmbd_auth_ntlmv2()
             -> calc_ntlmv2_hash()
             -> hmac_md5_usingrawkey(..., sess->sess_key)
             -> crypto_memneq() returns mismatch
          -> KEY_XCH arc4_crypt(..., sess->sess_key, ...)
    -> out_err without expiring the binding session

Derive the base session key into a local buffer and copy it to
sess->sess_key only after the proof matches. Return immediately on
authentication failure so KEY_XCH is only processed after successful
authentication.

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Fixes: f9929ef6a2a5 ("ksmbd: add support for key exchange")
Cc: stable@vger.kernel.org
Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/server/auth.c b/fs/smb/server/auth.c
index e99409fa721c..86f521e849d5 100644
--- a/fs/smb/server/auth.c
+++ b/fs/smb/server/auth.c
@@ -142,6 +142,7 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 {
 	char ntlmv2_hash[CIFS_ENCPWD_SIZE];
 	char ntlmv2_rsp[CIFS_HMAC_MD5_HASH_SIZE];
+	char sess_key[SMB2_NTLMV2_SESSKEY_SIZE];
 	struct hmac_md5_ctx ctx;
 	int rc;
 
@@ -164,12 +165,21 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 	/* Generate the session key */
 	hmac_md5_usingrawkey(ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE,
 			     ntlmv2_rsp, CIFS_HMAC_MD5_HASH_SIZE,
-			     sess->sess_key);
+			     sess_key);
 
 	if (crypto_memneq(ntlmv2->ntlmv2_hash, ntlmv2_rsp,
-			  CIFS_HMAC_MD5_HASH_SIZE))
-		return -EINVAL;
-	return 0;
+			  CIFS_HMAC_MD5_HASH_SIZE)) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	memcpy(sess->sess_key, sess_key, sizeof(sess_key));
+	rc = 0;
+out:
+	memzero_explicit(ntlmv2_hash, sizeof(ntlmv2_hash));
+	memzero_explicit(ntlmv2_rsp, sizeof(ntlmv2_rsp));
+	memzero_explicit(sess_key, sizeof(sess_key));
+	return rc;
 }
 
 /**
@@ -226,6 +236,8 @@ int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
 				nt_len - CIFS_ENCPWD_SIZE,
 				domain_name, conn->ntlmssp.cryptkey);
 	kfree(domain_name);
+	if (ret)
+		return ret;
 
 	/* The recovered secondary session key */
 	if (conn->ntlmssp.client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) {

[PATCH 6.18.y 1/4] ksmbd: Use SHA-512 library for SMB3.1.1 preauth hash

[Sasha Levin]

From: Eric Biggers <ebiggers@kernel.org>

[ Upstream commit e009cb1e3093977c5b96a1c6697a7dc9332222d5 ]

Convert ksmbd_gen_preauth_integrity_hash() to use the SHA-512 library
instead of a "sha512" crypto_shash.  This is simpler and faster.  With
the library there's no need to allocate memory, no need to handle
errors, and the SHA-512 code is accessed directly without inefficient
indirect calls and other unnecessary API overhead.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Stable-dep-of: 954d196bebb2 ("ksmbd: validate NTLMv2 response before updating session key")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/smb/server/Kconfig      |  2 +-
 fs/smb/server/auth.c       | 41 +++++++-------------------------------
 fs/smb/server/crypto_ctx.c |  8 --------
 fs/smb/server/crypto_ctx.h |  4 ----
 fs/smb/server/server.c     |  1 -
 5 files changed, 8 insertions(+), 48 deletions(-)

diff --git a/fs/smb/server/Kconfig b/fs/smb/server/Kconfig
index 6200c71298f667..4cb496a43375b4 100644
--- a/fs/smb/server/Kconfig
+++ b/fs/smb/server/Kconfig
@@ -13,10 +13,10 @@ config SMB_SERVER
 	select CRYPTO_LIB_ARC4
 	select CRYPTO_LIB_DES
 	select CRYPTO_LIB_SHA256
+	select CRYPTO_LIB_SHA512
 	select CRYPTO_LIB_UTILS
 	select CRYPTO_SHA256
 	select CRYPTO_CMAC
-	select CRYPTO_SHA512
 	select CRYPTO_AEAD2
 	select CRYPTO_CCM
 	select CRYPTO_GCM
diff --git a/fs/smb/server/auth.c b/fs/smb/server/auth.c
index b63f32c692bab0..0231c08efb5cfe 100644
--- a/fs/smb/server/auth.c
+++ b/fs/smb/server/auth.c
@@ -13,6 +13,7 @@
 #include <linux/xattr.h>
 #include <crypto/hash.h>
 #include <crypto/aead.h>
+#include <crypto/sha2.h>
 #include <crypto/utils.h>
 #include <linux/random.h>
 #include <linux/scatterlist.h>
@@ -918,48 +919,20 @@ int ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
 int ksmbd_gen_preauth_integrity_hash(struct ksmbd_conn *conn, char *buf,
 				     __u8 *pi_hash)
 {
-	int rc;
 	struct smb2_hdr *rcv_hdr = smb2_get_msg(buf);
 	char *all_bytes_msg = (char *)&rcv_hdr->ProtocolId;
 	int msg_size = get_rfc1002_len(buf);
-	struct ksmbd_crypto_ctx *ctx = NULL;
+	struct sha512_ctx sha_ctx;
 
 	if (conn->preauth_info->Preauth_HashId !=
 	    SMB2_PREAUTH_INTEGRITY_SHA512)
 		return -EINVAL;
 
-	ctx = ksmbd_crypto_ctx_find_sha512();
-	if (!ctx) {
-		ksmbd_debug(AUTH, "could not alloc sha512\n");
-		return -ENOMEM;
-	}
-
-	rc = crypto_shash_init(CRYPTO_SHA512(ctx));
-	if (rc) {
-		ksmbd_debug(AUTH, "could not init shashn");
-		goto out;
-	}
-
-	rc = crypto_shash_update(CRYPTO_SHA512(ctx), pi_hash, 64);
-	if (rc) {
-		ksmbd_debug(AUTH, "could not update with n\n");
-		goto out;
-	}
-
-	rc = crypto_shash_update(CRYPTO_SHA512(ctx), all_bytes_msg, msg_size);
-	if (rc) {
-		ksmbd_debug(AUTH, "could not update with n\n");
-		goto out;
-	}
-
-	rc = crypto_shash_final(CRYPTO_SHA512(ctx), pi_hash);
-	if (rc) {
-		ksmbd_debug(AUTH, "Could not generate hash err : %d\n", rc);
-		goto out;
-	}
-out:
-	ksmbd_release_crypto_ctx(ctx);
-	return rc;
+	sha512_init(&sha_ctx);
+	sha512_update(&sha_ctx, pi_hash, 64);
+	sha512_update(&sha_ctx, all_bytes_msg, msg_size);
+	sha512_final(&sha_ctx, pi_hash);
+	return 0;
 }
 
 static int ksmbd_get_encryption_key(struct ksmbd_work *work, __u64 ses_id,
diff --git a/fs/smb/server/crypto_ctx.c b/fs/smb/server/crypto_ctx.c
index 80bd68c8635ea7..1de41b10528bc4 100644
--- a/fs/smb/server/crypto_ctx.c
+++ b/fs/smb/server/crypto_ctx.c
@@ -75,9 +75,6 @@ static struct shash_desc *alloc_shash_desc(int id)
 	case CRYPTO_SHASH_CMACAES:
 		tfm = crypto_alloc_shash("cmac(aes)", 0, 0);
 		break;
-	case CRYPTO_SHASH_SHA512:
-		tfm = crypto_alloc_shash("sha512", 0, 0);
-		break;
 	default:
 		return NULL;
 	}
@@ -195,11 +192,6 @@ struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_cmacaes(void)
 	return ____crypto_shash_ctx_find(CRYPTO_SHASH_CMACAES);
 }
 
-struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_sha512(void)
-{
-	return ____crypto_shash_ctx_find(CRYPTO_SHASH_SHA512);
-}
-
 static struct ksmbd_crypto_ctx *____crypto_aead_ctx_find(int id)
 {
 	struct ksmbd_crypto_ctx *ctx;
diff --git a/fs/smb/server/crypto_ctx.h b/fs/smb/server/crypto_ctx.h
index ac64801d52d38a..4e8954acd8b8b9 100644
--- a/fs/smb/server/crypto_ctx.h
+++ b/fs/smb/server/crypto_ctx.h
@@ -13,7 +13,6 @@ enum {
 	CRYPTO_SHASH_HMACMD5	= 0,
 	CRYPTO_SHASH_HMACSHA256,
 	CRYPTO_SHASH_CMACAES,
-	CRYPTO_SHASH_SHA512,
 	CRYPTO_SHASH_MAX,
 };
 
@@ -38,13 +37,11 @@ struct ksmbd_crypto_ctx {
 #define CRYPTO_HMACMD5(c)	((c)->desc[CRYPTO_SHASH_HMACMD5])
 #define CRYPTO_HMACSHA256(c)	((c)->desc[CRYPTO_SHASH_HMACSHA256])
 #define CRYPTO_CMACAES(c)	((c)->desc[CRYPTO_SHASH_CMACAES])
-#define CRYPTO_SHA512(c)	((c)->desc[CRYPTO_SHASH_SHA512])
 
 #define CRYPTO_HMACMD5_TFM(c)	((c)->desc[CRYPTO_SHASH_HMACMD5]->tfm)
 #define CRYPTO_HMACSHA256_TFM(c)\
 				((c)->desc[CRYPTO_SHASH_HMACSHA256]->tfm)
 #define CRYPTO_CMACAES_TFM(c)	((c)->desc[CRYPTO_SHASH_CMACAES]->tfm)
-#define CRYPTO_SHA512_TFM(c)	((c)->desc[CRYPTO_SHASH_SHA512]->tfm)
 
 #define CRYPTO_GCM(c)		((c)->ccmaes[CRYPTO_AEAD_AES_GCM])
 #define CRYPTO_CCM(c)		((c)->ccmaes[CRYPTO_AEAD_AES_CCM])
@@ -53,7 +50,6 @@ void ksmbd_release_crypto_ctx(struct ksmbd_crypto_ctx *ctx);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacmd5(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacsha256(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_cmacaes(void);
-struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_sha512(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_gcm(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_ccm(void);
 void ksmbd_crypto_destroy(void);
diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c
index ef7a24e31f506f..b60b62aac11a04 100644
--- a/fs/smb/server/server.c
+++ b/fs/smb/server/server.c
@@ -628,7 +628,6 @@ MODULE_SOFTDEP("pre: nls");
 MODULE_SOFTDEP("pre: aes");
 MODULE_SOFTDEP("pre: cmac");
 MODULE_SOFTDEP("pre: sha256");
-MODULE_SOFTDEP("pre: sha512");
 MODULE_SOFTDEP("pre: aead2");
 MODULE_SOFTDEP("pre: ccm");
 MODULE_SOFTDEP("pre: gcm");
-- 
2.53.0

[PATCH 6.18.y 2/4] ksmbd: Use HMAC-SHA256 library for message signing and key generation

[Sasha Levin]

From: Eric Biggers <ebiggers@kernel.org>

[ Upstream commit 924067ef183bd17f39d790752190f99982524598 ]

Convert ksmbd_sign_smb2_pdu() and generate_key() to use the HMAC-SHA256
library instead of a "hmac(sha256)" crypto_shash.  This is simpler and
faster.  With the library there's no need to allocate memory, no need to
handle errors, and the HMAC-SHA256 code is accessed directly without
inefficient indirect calls and other unnecessary API overhead.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Stable-dep-of: 954d196bebb2 ("ksmbd: validate NTLMv2 response before updating session key")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/smb/server/Kconfig      |   1 -
 fs/smb/server/auth.c       | 176 ++++++++-----------------------------
 fs/smb/server/auth.h       |  10 +--
 fs/smb/server/crypto_ctx.c |   8 --
 fs/smb/server/crypto_ctx.h |   5 --
 fs/smb/server/server.c     |   1 -
 fs/smb/server/smb2pdu.c    |  25 ++----
 fs/smb/server/smb_common.h |   2 +-
 8 files changed, 52 insertions(+), 176 deletions(-)

diff --git a/fs/smb/server/Kconfig b/fs/smb/server/Kconfig
index 4cb496a43375b4..e2eae2b9a21be3 100644
--- a/fs/smb/server/Kconfig
+++ b/fs/smb/server/Kconfig
@@ -15,7 +15,6 @@ config SMB_SERVER
 	select CRYPTO_LIB_SHA256
 	select CRYPTO_LIB_SHA512
 	select CRYPTO_LIB_UTILS
-	select CRYPTO_SHA256
 	select CRYPTO_CMAC
 	select CRYPTO_AEAD2
 	select CRYPTO_CCM
diff --git a/fs/smb/server/auth.c b/fs/smb/server/auth.c
index 0231c08efb5cfe..01384a845a9b20 100644
--- a/fs/smb/server/auth.c
+++ b/fs/smb/server/auth.c
@@ -592,46 +592,16 @@ int ksmbd_krb5_authenticate(struct ksmbd_session *sess, char *in_blob,
  * @sig:	signature value generated for client request packet
  *
  */
-int ksmbd_sign_smb2_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
-			int n_vec, char *sig)
+void ksmbd_sign_smb2_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
+			 int n_vec, char *sig)
 {
-	struct ksmbd_crypto_ctx *ctx;
-	int rc, i;
-
-	ctx = ksmbd_crypto_ctx_find_hmacsha256();
-	if (!ctx) {
-		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
-		return -ENOMEM;
-	}
+	struct hmac_sha256_ctx ctx;
+	int i;
 
-	rc = crypto_shash_setkey(CRYPTO_HMACSHA256_TFM(ctx),
-				 key,
-				 SMB2_NTLMV2_SESSKEY_SIZE);
-	if (rc)
-		goto out;
-
-	rc = crypto_shash_init(CRYPTO_HMACSHA256(ctx));
-	if (rc) {
-		ksmbd_debug(AUTH, "hmacsha256 init error %d\n", rc);
-		goto out;
-	}
-
-	for (i = 0; i < n_vec; i++) {
-		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
-					 iov[i].iov_base,
-					 iov[i].iov_len);
-		if (rc) {
-			ksmbd_debug(AUTH, "hmacsha256 update error %d\n", rc);
-			goto out;
-		}
-	}
-
-	rc = crypto_shash_final(CRYPTO_HMACSHA256(ctx), sig);
-	if (rc)
-		ksmbd_debug(AUTH, "hmacsha256 generation error %d\n", rc);
-out:
-	ksmbd_release_crypto_ctx(ctx);
-	return rc;
+	hmac_sha256_init_usingrawkey(&ctx, key, SMB2_NTLMV2_SESSKEY_SIZE);
+	for (i = 0; i < n_vec; i++)
+		hmac_sha256_update(&ctx, iov[i].iov_base, iov[i].iov_len);
+	hmac_sha256_final(&ctx, sig);
 }
 
 /**
@@ -691,98 +661,39 @@ struct derivation {
 	bool binding;
 };
 
-static int generate_key(struct ksmbd_conn *conn, struct ksmbd_session *sess,
-			struct kvec label, struct kvec context, __u8 *key,
-			unsigned int key_size)
+static void generate_key(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+			 struct kvec label, struct kvec context, __u8 *key,
+			 unsigned int key_size)
 {
 	unsigned char zero = 0x0;
 	__u8 i[4] = {0, 0, 0, 1};
 	__u8 L128[4] = {0, 0, 0, 128};
 	__u8 L256[4] = {0, 0, 1, 0};
-	int rc;
 	unsigned char prfhash[SMB2_HMACSHA256_SIZE];
-	unsigned char *hashptr = prfhash;
-	struct ksmbd_crypto_ctx *ctx;
-
-	memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
-	memset(key, 0x0, key_size);
-
-	ctx = ksmbd_crypto_ctx_find_hmacsha256();
-	if (!ctx) {
-		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
-		return -ENOMEM;
-	}
+	struct hmac_sha256_ctx ctx;
 
-	rc = crypto_shash_setkey(CRYPTO_HMACSHA256_TFM(ctx),
-				 sess->sess_key,
-				 SMB2_NTLMV2_SESSKEY_SIZE);
-	if (rc)
-		goto smb3signkey_ret;
-
-	rc = crypto_shash_init(CRYPTO_HMACSHA256(ctx));
-	if (rc) {
-		ksmbd_debug(AUTH, "hmacsha256 init error %d\n", rc);
-		goto smb3signkey_ret;
-	}
-
-	rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), i, 4);
-	if (rc) {
-		ksmbd_debug(AUTH, "could not update with n\n");
-		goto smb3signkey_ret;
-	}
-
-	rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
-				 label.iov_base,
-				 label.iov_len);
-	if (rc) {
-		ksmbd_debug(AUTH, "could not update with label\n");
-		goto smb3signkey_ret;
-	}
-
-	rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), &zero, 1);
-	if (rc) {
-		ksmbd_debug(AUTH, "could not update with zero\n");
-		goto smb3signkey_ret;
-	}
-
-	rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
-				 context.iov_base,
-				 context.iov_len);
-	if (rc) {
-		ksmbd_debug(AUTH, "could not update with context\n");
-		goto smb3signkey_ret;
-	}
+	hmac_sha256_init_usingrawkey(&ctx, sess->sess_key,
+				     SMB2_NTLMV2_SESSKEY_SIZE);
+	hmac_sha256_update(&ctx, i, 4);
+	hmac_sha256_update(&ctx, label.iov_base, label.iov_len);
+	hmac_sha256_update(&ctx, &zero, 1);
+	hmac_sha256_update(&ctx, context.iov_base, context.iov_len);
 
 	if (key_size == SMB3_ENC_DEC_KEY_SIZE &&
 	    (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
 	     conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
-		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L256, 4);
+		hmac_sha256_update(&ctx, L256, 4);
 	else
-		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L128, 4);
-	if (rc) {
-		ksmbd_debug(AUTH, "could not update with L\n");
-		goto smb3signkey_ret;
-	}
+		hmac_sha256_update(&ctx, L128, 4);
 
-	rc = crypto_shash_final(CRYPTO_HMACSHA256(ctx), hashptr);
-	if (rc) {
-		ksmbd_debug(AUTH, "Could not generate hmacmd5 hash error %d\n",
-			    rc);
-		goto smb3signkey_ret;
-	}
-
-	memcpy(key, hashptr, key_size);
-
-smb3signkey_ret:
-	ksmbd_release_crypto_ctx(ctx);
-	return rc;
+	hmac_sha256_final(&ctx, prfhash);
+	memcpy(key, prfhash, key_size);
 }
 
 static int generate_smb3signingkey(struct ksmbd_session *sess,
 				   struct ksmbd_conn *conn,
 				   const struct derivation *signing)
 {
-	int rc;
 	struct channel *chann;
 	char *key;
 
@@ -795,10 +706,8 @@ static int generate_smb3signingkey(struct ksmbd_session *sess,
 	else
 		key = sess->smb3signingkey;
 
-	rc = generate_key(conn, sess, signing->label, signing->context, key,
-			  SMB3_SIGN_KEY_SIZE);
-	if (rc)
-		return rc;
+	generate_key(conn, sess, signing->label, signing->context, key,
+		     SMB3_SIGN_KEY_SIZE);
 
 	if (!(conn->dialect >= SMB30_PROT_ID && signing->binding))
 		memcpy(chann->smb3signingkey, key, SMB3_SIGN_KEY_SIZE);
@@ -850,32 +759,25 @@ struct derivation_twin {
 	struct derivation decryption;
 };
 
-static int generate_smb3encryptionkey(struct ksmbd_conn *conn,
-				      struct ksmbd_session *sess,
-				      const struct derivation_twin *ptwin)
+static void generate_smb3encryptionkey(struct ksmbd_conn *conn,
+				       struct ksmbd_session *sess,
+				       const struct derivation_twin *ptwin)
 {
-	int rc;
+	generate_key(conn, sess, ptwin->encryption.label,
+		     ptwin->encryption.context, sess->smb3encryptionkey,
+		     SMB3_ENC_DEC_KEY_SIZE);
 
-	rc = generate_key(conn, sess, ptwin->encryption.label,
-			  ptwin->encryption.context, sess->smb3encryptionkey,
-			  SMB3_ENC_DEC_KEY_SIZE);
-	if (rc)
-		return rc;
-
-	rc = generate_key(conn, sess, ptwin->decryption.label,
-			  ptwin->decryption.context,
-			  sess->smb3decryptionkey, SMB3_ENC_DEC_KEY_SIZE);
-	if (rc)
-		return rc;
+	generate_key(conn, sess, ptwin->decryption.label,
+		     ptwin->decryption.context,
+		     sess->smb3decryptionkey, SMB3_ENC_DEC_KEY_SIZE);
 
 	ksmbd_debug(AUTH, "generated SMB3 encryption/decryption keys\n");
 	ksmbd_debug(AUTH, "Cipher type   %d\n", conn->cipher_type);
 	ksmbd_debug(AUTH, "Session Id    %llu\n", sess->id);
-	return 0;
 }
 
-int ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
-				  struct ksmbd_session *sess)
+void ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
+				   struct ksmbd_session *sess)
 {
 	struct derivation_twin twin;
 	struct derivation *d;
@@ -892,11 +794,11 @@ int ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
 	d->context.iov_base = "ServerIn ";
 	d->context.iov_len = 10;
 
-	return generate_smb3encryptionkey(conn, sess, &twin);
+	generate_smb3encryptionkey(conn, sess, &twin);
 }
 
-int ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
-				   struct ksmbd_session *sess)
+void ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
+				    struct ksmbd_session *sess)
 {
 	struct derivation_twin twin;
 	struct derivation *d;
@@ -913,7 +815,7 @@ int ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
 	d->context.iov_base = sess->Preauth_HashValue;
 	d->context.iov_len = 64;
 
-	return generate_smb3encryptionkey(conn, sess, &twin);
+	generate_smb3encryptionkey(conn, sess, &twin);
 }
 
 int ksmbd_gen_preauth_integrity_hash(struct ksmbd_conn *conn, char *buf,
diff --git a/fs/smb/server/auth.h b/fs/smb/server/auth.h
index 6879a1bd1b91f5..6d351d61b0e575 100644
--- a/fs/smb/server/auth.h
+++ b/fs/smb/server/auth.h
@@ -52,18 +52,18 @@ ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
 				   struct ksmbd_conn *conn);
 int ksmbd_krb5_authenticate(struct ksmbd_session *sess, char *in_blob,
 			    int in_len,	char *out_blob, int *out_len);
-int ksmbd_sign_smb2_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
-			int n_vec, char *sig);
+void ksmbd_sign_smb2_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
+			 int n_vec, char *sig);
 int ksmbd_sign_smb3_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
 			int n_vec, char *sig);
 int ksmbd_gen_smb30_signingkey(struct ksmbd_session *sess,
 			       struct ksmbd_conn *conn);
 int ksmbd_gen_smb311_signingkey(struct ksmbd_session *sess,
 				struct ksmbd_conn *conn);
-int ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
-				  struct ksmbd_session *sess);
-int ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
+void ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
 				   struct ksmbd_session *sess);
+void ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
+				    struct ksmbd_session *sess);
 int ksmbd_gen_preauth_integrity_hash(struct ksmbd_conn *conn, char *buf,
 				     __u8 *pi_hash);
 #endif
diff --git a/fs/smb/server/crypto_ctx.c b/fs/smb/server/crypto_ctx.c
index 1de41b10528bc4..a5ec22ba8ae376 100644
--- a/fs/smb/server/crypto_ctx.c
+++ b/fs/smb/server/crypto_ctx.c
@@ -69,9 +69,6 @@ static struct shash_desc *alloc_shash_desc(int id)
 	case CRYPTO_SHASH_HMACMD5:
 		tfm = crypto_alloc_shash("hmac(md5)", 0, 0);
 		break;
-	case CRYPTO_SHASH_HMACSHA256:
-		tfm = crypto_alloc_shash("hmac(sha256)", 0, 0);
-		break;
 	case CRYPTO_SHASH_CMACAES:
 		tfm = crypto_alloc_shash("cmac(aes)", 0, 0);
 		break;
@@ -182,11 +179,6 @@ struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacmd5(void)
 	return ____crypto_shash_ctx_find(CRYPTO_SHASH_HMACMD5);
 }
 
-struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacsha256(void)
-{
-	return ____crypto_shash_ctx_find(CRYPTO_SHASH_HMACSHA256);
-}
-
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_cmacaes(void)
 {
 	return ____crypto_shash_ctx_find(CRYPTO_SHASH_CMACAES);
diff --git a/fs/smb/server/crypto_ctx.h b/fs/smb/server/crypto_ctx.h
index 4e8954acd8b8b9..c571d65a16f3eb 100644
--- a/fs/smb/server/crypto_ctx.h
+++ b/fs/smb/server/crypto_ctx.h
@@ -11,7 +11,6 @@
 
 enum {
 	CRYPTO_SHASH_HMACMD5	= 0,
-	CRYPTO_SHASH_HMACSHA256,
 	CRYPTO_SHASH_CMACAES,
 	CRYPTO_SHASH_MAX,
 };
@@ -35,12 +34,9 @@ struct ksmbd_crypto_ctx {
 };
 
 #define CRYPTO_HMACMD5(c)	((c)->desc[CRYPTO_SHASH_HMACMD5])
-#define CRYPTO_HMACSHA256(c)	((c)->desc[CRYPTO_SHASH_HMACSHA256])
 #define CRYPTO_CMACAES(c)	((c)->desc[CRYPTO_SHASH_CMACAES])
 
 #define CRYPTO_HMACMD5_TFM(c)	((c)->desc[CRYPTO_SHASH_HMACMD5]->tfm)
-#define CRYPTO_HMACSHA256_TFM(c)\
-				((c)->desc[CRYPTO_SHASH_HMACSHA256]->tfm)
 #define CRYPTO_CMACAES_TFM(c)	((c)->desc[CRYPTO_SHASH_CMACAES]->tfm)
 
 #define CRYPTO_GCM(c)		((c)->ccmaes[CRYPTO_AEAD_AES_GCM])
@@ -48,7 +44,6 @@ struct ksmbd_crypto_ctx {
 
 void ksmbd_release_crypto_ctx(struct ksmbd_crypto_ctx *ctx);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacmd5(void);
-struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacsha256(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_cmacaes(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_gcm(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_ccm(void);
diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c
index b60b62aac11a04..592ab7907ddf2c 100644
--- a/fs/smb/server/server.c
+++ b/fs/smb/server/server.c
@@ -627,7 +627,6 @@ MODULE_SOFTDEP("pre: md5");
 MODULE_SOFTDEP("pre: nls");
 MODULE_SOFTDEP("pre: aes");
 MODULE_SOFTDEP("pre: cmac");
-MODULE_SOFTDEP("pre: sha256");
 MODULE_SOFTDEP("pre: aead2");
 MODULE_SOFTDEP("pre: ccm");
 MODULE_SOFTDEP("pre: gcm");
diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index c012c5a93cc61f..191ac28805030e 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -1552,12 +1552,7 @@ static int ntlm_authenticate(struct ksmbd_work *work,
 
 	if (smb3_encryption_negotiated(conn) &&
 			!(req->Flags & SMB2_SESSION_REQ_FLAG_BINDING)) {
-		rc = conn->ops->generate_encryptionkey(conn, sess);
-		if (rc) {
-			ksmbd_debug(SMB,
-					"SMB3 encryption key generation failed\n");
-			return -EINVAL;
-		}
+		conn->ops->generate_encryptionkey(conn, sess);
 		sess->enc = true;
 		if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION)
 			rsp->SessionFlags = SMB2_SESSION_FLAG_ENCRYPT_DATA_LE;
@@ -1656,12 +1651,7 @@ static int krb5_authenticate(struct ksmbd_work *work,
 
 	if (smb3_encryption_negotiated(conn) &&
 	    !(req->Flags & SMB2_SESSION_REQ_FLAG_BINDING)) {
-		retval = conn->ops->generate_encryptionkey(conn, sess);
-		if (retval) {
-			ksmbd_debug(SMB,
-				    "SMB3 encryption key generation failed\n");
-			return -EINVAL;
-		}
+		conn->ops->generate_encryptionkey(conn, sess);
 		sess->enc = true;
 		if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION)
 			rsp->SessionFlags = SMB2_SESSION_FLAG_ENCRYPT_DATA_LE;
@@ -9018,9 +9008,8 @@ int smb2_check_sign_req(struct ksmbd_work *work)
 	iov[0].iov_base = (char *)&hdr->ProtocolId;
 	iov[0].iov_len = len;
 
-	if (ksmbd_sign_smb2_pdu(work->conn, work->sess->sess_key, iov, 1,
-				signature))
-		return 0;
+	ksmbd_sign_smb2_pdu(work->conn, work->sess->sess_key, iov, 1,
+			    signature);
 
 	if (crypto_memneq(signature, signature_req, SMB2_SIGNATURE_SIZE)) {
 		pr_err("bad smb2 signature\n");
@@ -9053,9 +9042,9 @@ void smb2_set_sign_rsp(struct ksmbd_work *work)
 		iov = &work->iov[work->iov_idx];
 	}
 
-	if (!ksmbd_sign_smb2_pdu(work->conn, work->sess->sess_key, iov, n_vec,
-				 signature))
-		memcpy(hdr->Signature, signature, SMB2_SIGNATURE_SIZE);
+	ksmbd_sign_smb2_pdu(work->conn, work->sess->sess_key, iov, n_vec,
+			    signature);
+	memcpy(hdr->Signature, signature, SMB2_SIGNATURE_SIZE);
 }
 
 /**
diff --git a/fs/smb/server/smb_common.h b/fs/smb/server/smb_common.h
index dac783b46545d0..e3be583e803da3 100644
--- a/fs/smb/server/smb_common.h
+++ b/fs/smb/server/smb_common.h
@@ -373,7 +373,7 @@ struct smb_version_ops {
 	int (*check_sign_req)(struct ksmbd_work *work);
 	void (*set_sign_rsp)(struct ksmbd_work *work);
 	int (*generate_signingkey)(struct ksmbd_session *sess, struct ksmbd_conn *conn);
-	int (*generate_encryptionkey)(struct ksmbd_conn *conn, struct ksmbd_session *sess);
+	void (*generate_encryptionkey)(struct ksmbd_conn *conn, struct ksmbd_session *sess);
 	bool (*is_transform_hdr)(void *buf);
 	int (*decrypt_req)(struct ksmbd_work *work);
 	int (*encrypt_resp)(struct ksmbd_work *work);
-- 
2.53.0

[PATCH 6.18.y 3/4] ksmbd: Use HMAC-MD5 library for NTLMv2

[Sasha Levin]

From: Eric Biggers <ebiggers@kernel.org>

[ Upstream commit 3a597e6e9701eb7af04864ffdc0a6a91bc8c6496 ]

For the HMAC-MD5 computations in NTLMv2, use the HMAC-MD5 library
instead of a "hmac(md5)" crypto_shash.  This is simpler and faster.
With the library there's no need to allocate memory, no need to handle
errors, and the HMAC-MD5 code is accessed directly without inefficient
indirect calls and other unnecessary API overhead.

To preserve the existing behavior of NTLMv2 support being disabled when
the kernel is booted with "fips=1", make ksmbd_auth_ntlmv2() check
fips_enabled itself.  Previously it relied on the error from
crypto_alloc_shash("hmac(md5)") being bubbled up.  I don't know for sure
that this is actually needed, but this preserves the existing behavior.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Stable-dep-of: 954d196bebb2 ("ksmbd: validate NTLMv2 response before updating session key")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/smb/server/Kconfig      |   3 +-
 fs/smb/server/auth.c       | 173 ++++++-------------------------------
 fs/smb/server/crypto_ctx.c |   8 --
 fs/smb/server/crypto_ctx.h |   6 +-
 fs/smb/server/server.c     |   2 -
 5 files changed, 27 insertions(+), 165 deletions(-)

diff --git a/fs/smb/server/Kconfig b/fs/smb/server/Kconfig
index e2eae2b9a21be3..12594879cb640f 100644
--- a/fs/smb/server/Kconfig
+++ b/fs/smb/server/Kconfig
@@ -7,11 +7,10 @@ config SMB_SERVER
 	select NLS_UTF8
 	select NLS_UCS2_UTILS
 	select CRYPTO
-	select CRYPTO_MD5
-	select CRYPTO_HMAC
 	select CRYPTO_ECB
 	select CRYPTO_LIB_ARC4
 	select CRYPTO_LIB_DES
+	select CRYPTO_LIB_MD5
 	select CRYPTO_LIB_SHA256
 	select CRYPTO_LIB_SHA512
 	select CRYPTO_LIB_UTILS
diff --git a/fs/smb/server/auth.c b/fs/smb/server/auth.c
index 01384a845a9b20..35e9cb63abcd77 100644
--- a/fs/smb/server/auth.c
+++ b/fs/smb/server/auth.c
@@ -13,6 +13,7 @@
 #include <linux/xattr.h>
 #include <crypto/hash.h>
 #include <crypto/aead.h>
+#include <crypto/md5.h>
 #include <crypto/sha2.h>
 #include <crypto/utils.h>
 #include <linux/random.h>
@@ -71,85 +72,16 @@ void ksmbd_copy_gss_neg_header(void *buf)
 	memcpy(buf, NEGOTIATE_GSS_HEADER, AUTH_GSS_LENGTH);
 }
 
-/**
- * ksmbd_gen_sess_key() - function to generate session key
- * @sess:	session of connection
- * @hash:	source hash value to be used for find session key
- * @hmac:	source hmac value to be used for finding session key
- *
- */
-static int ksmbd_gen_sess_key(struct ksmbd_session *sess, char *hash,
-			      char *hmac)
-{
-	struct ksmbd_crypto_ctx *ctx;
-	int rc;
-
-	ctx = ksmbd_crypto_ctx_find_hmacmd5();
-	if (!ctx) {
-		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
-		return -ENOMEM;
-	}
-
-	rc = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
-				 hash,
-				 CIFS_HMAC_MD5_HASH_SIZE);
-	if (rc) {
-		ksmbd_debug(AUTH, "hmacmd5 set key fail error %d\n", rc);
-		goto out;
-	}
-
-	rc = crypto_shash_init(CRYPTO_HMACMD5(ctx));
-	if (rc) {
-		ksmbd_debug(AUTH, "could not init hmacmd5 error %d\n", rc);
-		goto out;
-	}
-
-	rc = crypto_shash_update(CRYPTO_HMACMD5(ctx),
-				 hmac,
-				 SMB2_NTLMV2_SESSKEY_SIZE);
-	if (rc) {
-		ksmbd_debug(AUTH, "Could not update with response error %d\n", rc);
-		goto out;
-	}
-
-	rc = crypto_shash_final(CRYPTO_HMACMD5(ctx), sess->sess_key);
-	if (rc) {
-		ksmbd_debug(AUTH, "Could not generate hmacmd5 hash error %d\n", rc);
-		goto out;
-	}
-
-out:
-	ksmbd_release_crypto_ctx(ctx);
-	return rc;
-}
-
 static int calc_ntlmv2_hash(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 			    char *ntlmv2_hash, char *dname)
 {
 	int ret, len, conv_len;
 	wchar_t *domain = NULL;
 	__le16 *uniname = NULL;
-	struct ksmbd_crypto_ctx *ctx;
-
-	ctx = ksmbd_crypto_ctx_find_hmacmd5();
-	if (!ctx) {
-		ksmbd_debug(AUTH, "can't generate ntlmv2 hash\n");
-		return -ENOMEM;
-	}
+	struct hmac_md5_ctx ctx;
 
-	ret = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
-				  user_passkey(sess->user),
+	hmac_md5_init_usingrawkey(&ctx, user_passkey(sess->user),
 				  CIFS_ENCPWD_SIZE);
-	if (ret) {
-		ksmbd_debug(AUTH, "Could not set NT Hash as a key\n");
-		goto out;
-	}
-
-	ret = crypto_shash_init(CRYPTO_HMACMD5(ctx));
-	if (ret) {
-		ksmbd_debug(AUTH, "could not init hmacmd5\n");
-		goto out;
-	}
 
 	/* convert user_name to unicode */
 	len = strlen(user_name(sess->user));
@@ -167,13 +99,7 @@ static int calc_ntlmv2_hash(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 	}
 	UniStrupr(uniname);
 
-	ret = crypto_shash_update(CRYPTO_HMACMD5(ctx),
-				  (char *)uniname,
-				  UNICODE_LEN(conv_len));
-	if (ret) {
-		ksmbd_debug(AUTH, "Could not update with user\n");
-		goto out;
-	}
+	hmac_md5_update(&ctx, (const u8 *)uniname, UNICODE_LEN(conv_len));
 
 	/* Convert domain name or conn name to unicode and uppercase */
 	len = strlen(dname);
@@ -190,21 +116,12 @@ static int calc_ntlmv2_hash(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 		goto out;
 	}
 
-	ret = crypto_shash_update(CRYPTO_HMACMD5(ctx),
-				  (char *)domain,
-				  UNICODE_LEN(conv_len));
-	if (ret) {
-		ksmbd_debug(AUTH, "Could not update with domain\n");
-		goto out;
-	}
-
-	ret = crypto_shash_final(CRYPTO_HMACMD5(ctx), ntlmv2_hash);
-	if (ret)
-		ksmbd_debug(AUTH, "Could not generate md5 hash\n");
+	hmac_md5_update(&ctx, (const u8 *)domain, UNICODE_LEN(conv_len));
+	hmac_md5_final(&ctx, ntlmv2_hash);
+	ret = 0;
 out:
 	kfree(uniname);
 	kfree(domain);
-	ksmbd_release_crypto_ctx(ctx);
 	return ret;
 }
 
@@ -225,74 +142,34 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 {
 	char ntlmv2_hash[CIFS_ENCPWD_SIZE];
 	char ntlmv2_rsp[CIFS_HMAC_MD5_HASH_SIZE];
-	struct ksmbd_crypto_ctx *ctx = NULL;
-	char *construct = NULL;
-	int rc, len;
-
-	rc = calc_ntlmv2_hash(conn, sess, ntlmv2_hash, domain_name);
-	if (rc) {
-		ksmbd_debug(AUTH, "could not get v2 hash rc %d\n", rc);
-		goto out;
-	}
-
-	ctx = ksmbd_crypto_ctx_find_hmacmd5();
-	if (!ctx) {
-		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
-		return -ENOMEM;
-	}
-
-	rc = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
-				 ntlmv2_hash,
-				 CIFS_HMAC_MD5_HASH_SIZE);
-	if (rc) {
-		ksmbd_debug(AUTH, "Could not set NTLMV2 Hash as a key\n");
-		goto out;
-	}
-
-	rc = crypto_shash_init(CRYPTO_HMACMD5(ctx));
-	if (rc) {
-		ksmbd_debug(AUTH, "Could not init hmacmd5\n");
-		goto out;
-	}
+	struct hmac_md5_ctx ctx;
+	int rc;
 
-	len = CIFS_CRYPTO_KEY_SIZE + blen;
-	construct = kzalloc(len, KSMBD_DEFAULT_GFP);
-	if (!construct) {
-		rc = -ENOMEM;
-		goto out;
+	if (fips_enabled) {
+		ksmbd_debug(AUTH, "NTLMv2 support is disabled due to FIPS\n");
+		return -EOPNOTSUPP;
 	}
 
-	memcpy(construct, cryptkey, CIFS_CRYPTO_KEY_SIZE);
-	memcpy(construct + CIFS_CRYPTO_KEY_SIZE, &ntlmv2->blob_signature, blen);
-
-	rc = crypto_shash_update(CRYPTO_HMACMD5(ctx), construct, len);
+	rc = calc_ntlmv2_hash(conn, sess, ntlmv2_hash, domain_name);
 	if (rc) {
-		ksmbd_debug(AUTH, "Could not update with response\n");
-		goto out;
+		ksmbd_debug(AUTH, "could not get v2 hash rc %d\n", rc);
+		return rc;
 	}
 
-	rc = crypto_shash_final(CRYPTO_HMACMD5(ctx), ntlmv2_rsp);
-	if (rc) {
-		ksmbd_debug(AUTH, "Could not generate md5 hash\n");
-		goto out;
-	}
-	ksmbd_release_crypto_ctx(ctx);
-	ctx = NULL;
+	hmac_md5_init_usingrawkey(&ctx, ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
+	hmac_md5_update(&ctx, cryptkey, CIFS_CRYPTO_KEY_SIZE);
+	hmac_md5_update(&ctx, (const u8 *)&ntlmv2->blob_signature, blen);
+	hmac_md5_final(&ctx, ntlmv2_rsp);
 
-	rc = ksmbd_gen_sess_key(sess, ntlmv2_hash, ntlmv2_rsp);
-	if (rc) {
-		ksmbd_debug(AUTH, "Could not generate sess key\n");
-		goto out;
-	}
+	/* Generate the session key */
+	hmac_md5_usingrawkey(ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE,
+			     ntlmv2_rsp, CIFS_HMAC_MD5_HASH_SIZE,
+			     sess->sess_key);
 
 	if (crypto_memneq(ntlmv2->ntlmv2_hash, ntlmv2_rsp,
 			  CIFS_HMAC_MD5_HASH_SIZE))
-		rc = -EINVAL;
-out:
-	if (ctx)
-		ksmbd_release_crypto_ctx(ctx);
-	kfree(construct);
-	return rc;
+		return -EINVAL;
+	return 0;
 }
 
 /**
diff --git a/fs/smb/server/crypto_ctx.c b/fs/smb/server/crypto_ctx.c
index a5ec22ba8ae376..fe29d186baf687 100644
--- a/fs/smb/server/crypto_ctx.c
+++ b/fs/smb/server/crypto_ctx.c
@@ -66,9 +66,6 @@ static struct shash_desc *alloc_shash_desc(int id)
 	struct shash_desc *shash;
 
 	switch (id) {
-	case CRYPTO_SHASH_HMACMD5:
-		tfm = crypto_alloc_shash("hmac(md5)", 0, 0);
-		break;
 	case CRYPTO_SHASH_CMACAES:
 		tfm = crypto_alloc_shash("cmac(aes)", 0, 0);
 		break;
@@ -174,11 +171,6 @@ static struct ksmbd_crypto_ctx *____crypto_shash_ctx_find(int id)
 	return NULL;
 }
 
-struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacmd5(void)
-{
-	return ____crypto_shash_ctx_find(CRYPTO_SHASH_HMACMD5);
-}
-
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_cmacaes(void)
 {
 	return ____crypto_shash_ctx_find(CRYPTO_SHASH_CMACAES);
diff --git a/fs/smb/server/crypto_ctx.h b/fs/smb/server/crypto_ctx.h
index c571d65a16f3eb..b9476ed520ae4c 100644
--- a/fs/smb/server/crypto_ctx.h
+++ b/fs/smb/server/crypto_ctx.h
@@ -10,8 +10,7 @@
 #include <crypto/aead.h>
 
 enum {
-	CRYPTO_SHASH_HMACMD5	= 0,
-	CRYPTO_SHASH_CMACAES,
+	CRYPTO_SHASH_CMACAES	= 0,
 	CRYPTO_SHASH_MAX,
 };
 
@@ -33,17 +32,14 @@ struct ksmbd_crypto_ctx {
 	struct crypto_aead		*ccmaes[CRYPTO_AEAD_MAX];
 };
 
-#define CRYPTO_HMACMD5(c)	((c)->desc[CRYPTO_SHASH_HMACMD5])
 #define CRYPTO_CMACAES(c)	((c)->desc[CRYPTO_SHASH_CMACAES])
 
-#define CRYPTO_HMACMD5_TFM(c)	((c)->desc[CRYPTO_SHASH_HMACMD5]->tfm)
 #define CRYPTO_CMACAES_TFM(c)	((c)->desc[CRYPTO_SHASH_CMACAES]->tfm)
 
 #define CRYPTO_GCM(c)		((c)->ccmaes[CRYPTO_AEAD_AES_GCM])
 #define CRYPTO_CCM(c)		((c)->ccmaes[CRYPTO_AEAD_AES_CCM])
 
 void ksmbd_release_crypto_ctx(struct ksmbd_crypto_ctx *ctx);
-struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacmd5(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_cmacaes(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_gcm(void);
 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_ccm(void);
diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c
index 592ab7907ddf2c..68931cc66e34b1 100644
--- a/fs/smb/server/server.c
+++ b/fs/smb/server/server.c
@@ -622,8 +622,6 @@ MODULE_AUTHOR("Namjae Jeon <linkinjeon@kernel.org>");
 MODULE_DESCRIPTION("Linux kernel CIFS/SMB SERVER");
 MODULE_LICENSE("GPL");
 MODULE_SOFTDEP("pre: ecb");
-MODULE_SOFTDEP("pre: hmac");
-MODULE_SOFTDEP("pre: md5");
 MODULE_SOFTDEP("pre: nls");
 MODULE_SOFTDEP("pre: aes");
 MODULE_SOFTDEP("pre: cmac");
-- 
2.53.0

[PATCH 6.18.y 4/4] ksmbd: validate NTLMv2 response before updating session key

[Sasha Levin]

From: Haofeng Li <lihaofeng@kylinos.cn>

[ Upstream commit 954d196bebb2b50151cb96454c72dc113b2af1ac ]

ksmbd_auth_ntlmv2() derives the NTLMv2 session key into
sess->sess_key before it verifies the NTLMv2 response.
ksmbd_decode_ntlmssp_auth_blob() then continues into KEY_XCH even
when ksmbd_auth_ntlmv2() failed.

With SMB3 multichannel binding, the failed authentication operates on
an existing session and the session setup error path does not expire
binding sessions. A client can send a binding session setup with a
bad NT proof and KEY_XCH and still modify sess->sess_key before
STATUS_LOGON_FAILURE is returned.

Relevant path:

  smb2_sess_setup()
    -> conn->binding = true
    -> ntlm_authenticate()
       -> session_user()
       -> ksmbd_decode_ntlmssp_auth_blob()
          -> ksmbd_auth_ntlmv2()
             -> calc_ntlmv2_hash()
             -> hmac_md5_usingrawkey(..., sess->sess_key)
             -> crypto_memneq() returns mismatch
          -> KEY_XCH arc4_crypt(..., sess->sess_key, ...)
    -> out_err without expiring the binding session

Derive the base session key into a local buffer and copy it to
sess->sess_key only after the proof matches. Return immediately on
authentication failure so KEY_XCH is only processed after successful
authentication.

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Fixes: f9929ef6a2a5 ("ksmbd: add support for key exchange")
Cc: stable@vger.kernel.org
Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/smb/server/auth.c | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/fs/smb/server/auth.c b/fs/smb/server/auth.c
index 35e9cb63abcd77..a778275207fe78 100644
--- a/fs/smb/server/auth.c
+++ b/fs/smb/server/auth.c
@@ -142,6 +142,7 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 {
 	char ntlmv2_hash[CIFS_ENCPWD_SIZE];
 	char ntlmv2_rsp[CIFS_HMAC_MD5_HASH_SIZE];
+	char sess_key[SMB2_NTLMV2_SESSKEY_SIZE];
 	struct hmac_md5_ctx ctx;
 	int rc;
 
@@ -164,12 +165,21 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 	/* Generate the session key */
 	hmac_md5_usingrawkey(ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE,
 			     ntlmv2_rsp, CIFS_HMAC_MD5_HASH_SIZE,
-			     sess->sess_key);
+			     sess_key);
 
 	if (crypto_memneq(ntlmv2->ntlmv2_hash, ntlmv2_rsp,
-			  CIFS_HMAC_MD5_HASH_SIZE))
-		return -EINVAL;
-	return 0;
+			  CIFS_HMAC_MD5_HASH_SIZE)) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	memcpy(sess->sess_key, sess_key, sizeof(sess_key));
+	rc = 0;
+out:
+	memzero_explicit(ntlmv2_hash, sizeof(ntlmv2_hash));
+	memzero_explicit(ntlmv2_rsp, sizeof(ntlmv2_rsp));
+	memzero_explicit(sess_key, sizeof(sess_key));
+	return rc;
 }
 
 /**
@@ -226,6 +236,8 @@ int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
 				nt_len - CIFS_ENCPWD_SIZE,
 				domain_name, conn->ntlmssp.cryptkey);
 	kfree(domain_name);
+	if (ret)
+		return ret;
 
 	/* The recovered secondary session key */
 	if (conn->ntlmssp.client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) {
-- 
2.53.0