Merge tag '5.15-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs client updates from Steve French:
 "Eleven cifs/smb3 client fixes:

   - mostly restructuring to allow disabling less secure algorithms
     (this will allow eventual removing rc4 and md4 from general use in
     the kernel)

   - four fixes, including two for stable

   - enable r/w support with fscache and cifs.ko

  I am working on a larger set of changes (the usual ... multichannel,
  auth and signing improvements), but wanted to get these in earlier to
  reduce chance of merge conflicts later in the merge window"

* tag '5.15-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Do not leak EDEADLK to dgetents64 for STATUS_USER_SESSION_DELETED
  cifs: add cifs_common directory to MAINTAINERS file
  cifs: cifs_md4 convert to SPDX identifier
  cifs: create a MD4 module and switch cifs.ko to use it
  cifs: fork arc4 and create a separate module for it for cifs and other users
  cifs: remove support for NTLM and weaker authentication algorithms
  cifs: enable fscache usage even for files opened as rw
  oid_registry: Add OIDs for missing Spnego auth mechanisms to Macs
  smb3: fix posix extensions mount option
  cifs: fix wrong release in sess_alloc_buffer() failed path
  CIFS: Fix a potencially linear read overflow

28 files changed, 477 insertions, 763 deletions

diff --git a/fs/Kconfig b/fs/Kconfig
index 8d6ac56d6fcd..b11bd4b387e1 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -348,8 +348,15 @@ config NFS_V4_2_SSC_HELPER
 
 source "net/sunrpc/Kconfig"
 source "fs/ceph/Kconfig"
+
 source "fs/cifs/Kconfig"
 source "fs/ksmbd/Kconfig"
+
+config CIFS_COMMON
+	tristate
+	default y if CIFS=y
+	default m if CIFS=m
+
 source "fs/coda/Kconfig"
 source "fs/afs/Kconfig"
 source "fs/9p/Kconfig"
diff --git a/fs/Makefile b/fs/Makefile
index b7e65c39f98d..354e2ba3ee67 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -96,6 +96,7 @@ obj-$(CONFIG_LOCKD)		+= lockd/
 obj-$(CONFIG_NLS)		+= nls/
 obj-$(CONFIG_UNICODE)		+= unicode/
 obj-$(CONFIG_SYSV_FS)		+= sysv/
+obj-$(CONFIG_CIFS_COMMON)	+= cifs_common/
 obj-$(CONFIG_CIFS)		+= cifs/
 obj-$(CONFIG_SMB_SERVER)	+= ksmbd/
 obj-$(CONFIG_HPFS_FS)		+= hpfs/
diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index 7364950a9ef4..3b7e3b9e4fd2 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -4,19 +4,16 @@ config CIFS
 	depends on INET
 	select NLS
 	select CRYPTO
-	select CRYPTO_MD4
 	select CRYPTO_MD5
 	select CRYPTO_SHA256
 	select CRYPTO_SHA512
 	select CRYPTO_CMAC
 	select CRYPTO_HMAC
-	select CRYPTO_LIB_ARC4
 	select CRYPTO_AEAD2
 	select CRYPTO_CCM
 	select CRYPTO_GCM
 	select CRYPTO_ECB
 	select CRYPTO_AES
-	select CRYPTO_LIB_DES
 	select KEYS
 	select DNS_RESOLVER
 	select ASN1
@@ -85,33 +82,6 @@ config CIFS_ALLOW_INSECURE_LEGACY
 
 	  If unsure, say Y.
 
-config CIFS_WEAK_PW_HASH
-	bool "Support legacy servers which use weaker LANMAN security"
-	depends on CIFS && CIFS_ALLOW_INSECURE_LEGACY
-	help
-	  Modern CIFS servers including Samba and most Windows versions
-	  (since 1997) support stronger NTLM (and even NTLMv2 and Kerberos)
-	  security mechanisms. These hash the password more securely
-	  than the mechanisms used in the older LANMAN version of the
-	  SMB protocol but LANMAN based authentication is needed to
-	  establish sessions with some old SMB servers.
-
-	  Enabling this option allows the cifs module to mount to older
-	  LANMAN based servers such as OS/2 and Windows 95, but such
-	  mounts may be less secure than mounts using NTLM or more recent
-	  security mechanisms if you are on a public network.  Unless you
-	  have a need to access old SMB servers (and are on a private
-	  network) you probably want to say N.  Even if this support
-	  is enabled in the kernel build, LANMAN authentication will not be
-	  used automatically. At runtime LANMAN mounts are disabled but
-	  can be set to required (or optional) either in
-	  /proc/fs/cifs (see Documentation/admin-guide/cifs/usage.rst for
-	  more detail) or via an option on the mount command. This support
-	  is disabled by default in order to reduce the possibility of a
-	  downgrade attack.
-
-	  If unsure, say N.
-
 config CIFS_UPCALL
 	bool "Kerberos/SPNEGO advanced session setup"
 	depends on CIFS
diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index 8857ac7e7a14..51a824fc926a 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -250,9 +250,6 @@ static int cifs_debug_data_proc_show(struct seq_file *m, void *v)
 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 	seq_printf(m, ",ALLOW_INSECURE_LEGACY");
 #endif
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-	seq_printf(m, ",WEAK_PW_HASH");
-#endif
 #ifdef CONFIG_CIFS_POSIX
 	seq_printf(m, ",CIFS_POSIX");
 #endif
@@ -929,14 +926,6 @@ cifs_security_flags_handle_must_flags(unsigned int *flags)
 		*flags = CIFSSEC_MUST_NTLMSSP;
 	else if ((*flags & CIFSSEC_MUST_NTLMV2) == CIFSSEC_MUST_NTLMV2)
 		*flags = CIFSSEC_MUST_NTLMV2;
-	else if ((*flags & CIFSSEC_MUST_NTLM) == CIFSSEC_MUST_NTLM)
-		*flags = CIFSSEC_MUST_NTLM;
-	else if (CIFSSEC_MUST_LANMAN &&
-		 (*flags & CIFSSEC_MUST_LANMAN) == CIFSSEC_MUST_LANMAN)
-		*flags = CIFSSEC_MUST_LANMAN;
-	else if (CIFSSEC_MUST_PLNTXT &&
-		 (*flags & CIFSSEC_MUST_PLNTXT) == CIFSSEC_MUST_PLNTXT)
-		*flags = CIFSSEC_MUST_PLNTXT;
 
 	*flags |= signflags;
 }
diff --git a/fs/cifs/cifs_swn.c b/fs/cifs/cifs_swn.c
index 93b47818c6c2..12bde7bfda86 100644
--- a/fs/cifs/cifs_swn.c
+++ b/fs/cifs/cifs_swn.c
@@ -147,8 +147,6 @@ static int cifs_swn_send_register_message(struct cifs_swn_reg *swnreg)
 			goto nlmsg_fail;
 		}
 		break;
-	case LANMAN:
-	case NTLM:
 	case NTLMv2:
 	case RawNTLMSSP:
 		ret = cifs_swn_auth_info_ntlm(swnreg->tcon, skb);
diff --git a/fs/cifs/cifs_unicode.c b/fs/cifs/cifs_unicode.c
index 9bd03a231032..171ad8b42107 100644
--- a/fs/cifs/cifs_unicode.c
+++ b/fs/cifs/cifs_unicode.c
@@ -358,14 +358,9 @@ cifs_strndup_from_utf16(const char *src, const int maxlen,
 		if (!dst)
 			return NULL;
 		cifs_from_utf16(dst, (__le16 *) src, len, maxlen, codepage,
-			       NO_MAP_UNI_RSVD);
+				NO_MAP_UNI_RSVD);
 	} else {
-		len = strnlen(src, maxlen);
-		len++;
-		dst = kmalloc(len, GFP_KERNEL);
-		if (!dst)
-			return NULL;
-		strlcpy(dst, src, len);
+		dst = kstrndup(src, maxlen, GFP_KERNEL);
 	}
 
 	return dst;
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index ecf15d845dbd..6679e07e533e 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -22,7 +22,7 @@
 #include <linux/random.h>
 #include <linux/highmem.h>
 #include <linux/fips.h>
-#include <crypto/arc4.h>
+#include "../cifs_common/arc4.h"
 #include <crypto/aead.h>
 
 int __cifs_calc_signature(struct smb_rqst *rqst,
@@ -250,87 +250,6 @@ int cifs_verify_signature(struct smb_rqst *rqst,
 
 }
 
-/* first calculate 24 bytes ntlm response and then 16 byte session key */
-int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
-{
-	int rc = 0;
-	unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
-	char temp_key[CIFS_SESS_KEY_SIZE];
-
-	if (!ses)
-		return -EINVAL;
-
-	ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
-	if (!ses->auth_key.response)
-		return -ENOMEM;
-
-	ses->auth_key.len = temp_len;
-
-	rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
-			ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
-	if (rc) {
-		cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
-			 __func__, rc);
-		return rc;
-	}
-
-	rc = E_md4hash(ses->password, temp_key, nls_cp);
-	if (rc) {
-		cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
-			 __func__, rc);
-		return rc;
-	}
-
-	rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
-	if (rc)
-		cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
-			 __func__, rc);
-
-	return rc;
-}
-
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
-			char *lnm_session_key)
-{
-	int i, len;
-	int rc;
-	char password_with_pad[CIFS_ENCPWD_SIZE] = {0};
-
-	if (password) {
-		for (len = 0; len < CIFS_ENCPWD_SIZE; len++)
-			if (!password[len])
-				break;
-
-		memcpy(password_with_pad, password, len);
-	}
-
-	if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
-		memcpy(lnm_session_key, password_with_pad,
-			CIFS_ENCPWD_SIZE);
-		return 0;
-	}
-
-	/* calculate old style session key */
-	/* calling toupper is less broken than repeatedly
-	calling nls_toupper would be since that will never
-	work for UTF8, but neither handles multibyte code pages
-	but the only alternative would be converting to UCS-16 (Unicode)
-	(using a routine something like UniStrupr) then
-	uppercasing and then converting back from Unicode - which
-	would only worth doing it if we knew it were utf8. Basically
-	utf8 and other multibyte codepages each need their own strupper
-	function since a byte at a time will ont work. */
-
-	for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
-		password_with_pad[i] = toupper(password_with_pad[i]);
-
-	rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
-
-	return rc;
-}
-#endif /* CIFS_WEAK_PW_HASH */
-
 /* Build a proper attribute value/target info pairs blob.
  * Fill in netbios and dns domain name and workstation name
  * and client time (total five av pairs and + one end of fields indicator.
@@ -780,9 +699,9 @@ calc_seckey(struct cifs_ses *ses)
 		return -ENOMEM;
 	}
 
-	arc4_setkey(ctx_arc4, ses->auth_key.response, CIFS_SESS_KEY_SIZE);
-	arc4_crypt(ctx_arc4, ses->ntlmssp->ciphertext, sec_key,
-		   CIFS_CPHTXT_SIZE);
+	cifs_arc4_setkey(ctx_arc4, ses->auth_key.response, CIFS_SESS_KEY_SIZE);
+	cifs_arc4_crypt(ctx_arc4, ses->ntlmssp->ciphertext, sec_key,
+			CIFS_CPHTXT_SIZE);
 
 	/* make secondary_key/nonce as session key */
 	memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 64b71c4e2a9d..8c20bfa187ac 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -399,7 +399,6 @@ cifs_evict_inode(struct inode *inode)
 {
 	truncate_inode_pages_final(&inode->i_data);
 	clear_inode(inode);
-	cifs_fscache_release_inode_cookie(inode);
 }
 
 static void
@@ -438,15 +437,9 @@ cifs_show_security(struct seq_file *s, struct cifs_ses *ses)
 	seq_puts(s, ",sec=");
 
 	switch (ses->sectype) {
-	case LANMAN:
-		seq_puts(s, "lanman");
-		break;
 	case NTLMv2:
 		seq_puts(s, "ntlmv2");
 		break;
-	case NTLM:
-		seq_puts(s, "ntlm");
-		break;
 	case Kerberos:
 		seq_puts(s, "krb5");
 		break;
@@ -1755,7 +1748,6 @@ MODULE_DESCRIPTION
 MODULE_VERSION(CIFS_VERSION);
 MODULE_SOFTDEP("ecb");
 MODULE_SOFTDEP("hmac");
-MODULE_SOFTDEP("md4");
 MODULE_SOFTDEP("md5");
 MODULE_SOFTDEP("nls");
 MODULE_SOFTDEP("aes");
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index c6a9542ca281..c068f7d8d879 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -114,8 +114,6 @@ enum statusEnum {
 
 enum securityEnum {
 	Unspecified = 0,	/* not specified */
-	LANMAN,			/* Legacy LANMAN auth */
-	NTLM,			/* Legacy NTLM012 auth with NTLM hash */
 	NTLMv2,			/* Legacy NTLM auth with NTLMv2 hash */
 	RawNTLMSSP,		/* NTLMSSP without SPNEGO, NTLMv2 hash */
 	Kerberos,		/* Kerberos via SPNEGO */
@@ -634,7 +632,6 @@ struct TCP_Server_Info {
 	struct session_key session_key;
 	unsigned long lstrp; /* when we got last response from this server */
 	struct cifs_secmech secmech; /* crypto sec mech functs, descriptors */
-#define	CIFS_NEGFLAVOR_LANMAN	0	/* wct == 13, LANMAN */
 #define	CIFS_NEGFLAVOR_UNENCAP	1	/* wct == 17, but no ext_sec */
 #define	CIFS_NEGFLAVOR_EXTENDED	2	/* wct == 17, ext_sec bit set */
 	char	negflavor;	/* NEGOTIATE response flavor */
@@ -1734,16 +1731,8 @@ static inline bool is_retryable_error(int error)
 
 /* Security Flags: indicate type of session setup needed */
 #define   CIFSSEC_MAY_SIGN	0x00001
-#define   CIFSSEC_MAY_NTLM	0x00002
 #define   CIFSSEC_MAY_NTLMV2	0x00004
 #define   CIFSSEC_MAY_KRB5	0x00008
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-#define   CIFSSEC_MAY_LANMAN	0x00010
-#define   CIFSSEC_MAY_PLNTXT	0x00020
-#else
-#define   CIFSSEC_MAY_LANMAN    0
-#define   CIFSSEC_MAY_PLNTXT    0
-#endif /* weak passwords */
 #define   CIFSSEC_MAY_SEAL	0x00040 /* not supported yet */
 #define   CIFSSEC_MAY_NTLMSSP	0x00080 /* raw ntlmssp with ntlmv2 */
 
@@ -1751,32 +1740,19 @@ static inline bool is_retryable_error(int error)
 /* note that only one of the following can be set so the
 result of setting MUST flags more than once will be to
 require use of the stronger protocol */
-#define   CIFSSEC_MUST_NTLM	0x02002
 #define   CIFSSEC_MUST_NTLMV2	0x04004
 #define   CIFSSEC_MUST_KRB5	0x08008
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-#define   CIFSSEC_MUST_LANMAN	0x10010
-#define   CIFSSEC_MUST_PLNTXT	0x20020
-#ifdef CONFIG_CIFS_UPCALL
-#define   CIFSSEC_MASK          0xBF0BF /* allows weak security but also krb5 */
-#else
-#define   CIFSSEC_MASK          0xB70B7 /* current flags supported if weak */
-#endif /* UPCALL */
-#else /* do not allow weak pw hash */
-#define   CIFSSEC_MUST_LANMAN	0
-#define   CIFSSEC_MUST_PLNTXT	0
 #ifdef CONFIG_CIFS_UPCALL
 #define   CIFSSEC_MASK          0x8F08F /* flags supported if no weak allowed */
 #else
 #define	  CIFSSEC_MASK          0x87087 /* flags supported if no weak allowed */
 #endif /* UPCALL */
-#endif /* WEAK_PW_HASH */
 #define   CIFSSEC_MUST_SEAL	0x40040 /* not supported yet */
 #define   CIFSSEC_MUST_NTLMSSP	0x80080 /* raw ntlmssp with ntlmv2 */
 
 #define   CIFSSEC_DEF (CIFSSEC_MAY_SIGN | CIFSSEC_MAY_NTLMV2 | CIFSSEC_MAY_NTLMSSP)
-#define   CIFSSEC_MAX (CIFSSEC_MUST_SIGN | CIFSSEC_MUST_NTLMV2)
-#define   CIFSSEC_AUTH_MASK (CIFSSEC_MAY_NTLM | CIFSSEC_MAY_NTLMV2 | CIFSSEC_MAY_LANMAN | CIFSSEC_MAY_PLNTXT | CIFSSEC_MAY_KRB5 | CIFSSEC_MAY_NTLMSSP)
+#define   CIFSSEC_MAX (CIFSSEC_MUST_NTLMV2)
+#define   CIFSSEC_AUTH_MASK (CIFSSEC_MAY_NTLMV2 | CIFSSEC_MAY_KRB5 | CIFSSEC_MAY_NTLMSSP)
 /*
  *****************************************************************
  * All constants go here
@@ -1940,10 +1916,6 @@ static inline char *get_security_type_str(enum securityEnum sectype)
 		return "Kerberos";
 	case NTLMv2:
 		return "NTLMv2";
-	case NTLM:
-		return "NTLM";
-	case LANMAN:
-		return "LANMAN";
 	default:
 		return "Unknown";
 	}
diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h
index f6e235001358..dc920e206336 100644
--- a/fs/cifs/cifspdu.h
+++ b/fs/cifs/cifspdu.h
@@ -14,13 +14,7 @@
 #include <asm/unaligned.h>
 #include "smbfsctl.h"
 
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-#define LANMAN_PROT 0
-#define LANMAN2_PROT 1
-#define CIFS_PROT   2
-#else
 #define CIFS_PROT   0
-#endif
 #define POSIX_PROT  (CIFS_PROT+1)
 #define BAD_PROT 0xFFFF
 
@@ -505,30 +499,8 @@ typedef struct negotiate_req {
 	unsigned char DialectsArray[1];
 } __attribute__((packed)) NEGOTIATE_REQ;
 
-/* Dialect index is 13 for LANMAN */
-
 #define MIN_TZ_ADJ (15 * 60) /* minimum grid for timezones in seconds */
 
-typedef struct lanman_neg_rsp {
-	struct smb_hdr hdr;	/* wct = 13 */
-	__le16 DialectIndex;
-	__le16 SecurityMode;
-	__le16 MaxBufSize;
-	__le16 MaxMpxCount;
-	__le16 MaxNumberVcs;
-	__le16 RawMode;
-	__le32 SessionKey;
-	struct {
-		__le16 Time;
-		__le16 Date;
-	} __attribute__((packed)) SrvTime;
-	__le16 ServerTimeZone;
-	__le16 EncryptionKeyLength;
-	__le16 Reserved;
-	__u16  ByteCount;
-	unsigned char EncryptionKey[1];
-} __attribute__((packed)) LANMAN_NEG_RSP;
-
 #define READ_RAW_ENABLE 1
 #define WRITE_RAW_ENABLE 2
 #define RAW_ENABLE (READ_RAW_ENABLE | WRITE_RAW_ENABLE)
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index e0def0f0714b..f9740c21ca3d 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -498,19 +498,12 @@ extern int cifs_sign_smb(struct smb_hdr *, struct TCP_Server_Info *, __u32 *);
 extern int cifs_verify_signature(struct smb_rqst *rqst,
 				 struct TCP_Server_Info *server,
 				__u32 expected_sequence_number);
-extern int SMBNTencrypt(unsigned char *, unsigned char *, unsigned char *,
-			const struct nls_table *);
-extern int setup_ntlm_response(struct cifs_ses *, const struct nls_table *);
 extern int setup_ntlmv2_rsp(struct cifs_ses *, const struct nls_table *);
 extern void cifs_crypto_secmech_release(struct TCP_Server_Info *server);
 extern int calc_seckey(struct cifs_ses *);
 extern int generate_smb30signingkey(struct cifs_ses *);
 extern int generate_smb311signingkey(struct cifs_ses *);
 
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-extern int calc_lanman_hash(const char *password, const char *cryptkey,
-				bool encrypt, char *lnm_session_key);
-#endif /* CIFS_WEAK_PW_HASH */
 extern int CIFSSMBCopy(unsigned int xid,
 			struct cifs_tcon *source_tcon,
 			const char *fromName,
@@ -547,11 +540,8 @@ extern int check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
 			      struct cifs_sb_info *cifs_sb,
 			      struct cifs_fattr *fattr,
 			      const unsigned char *path);
-extern int mdfour(unsigned char *, unsigned char *, int);
 extern int E_md4hash(const unsigned char *passwd, unsigned char *p16,
 			const struct nls_table *codepage);
-extern int SMBencrypt(unsigned char *passwd, const unsigned char *c8,
-			unsigned char *p24);
 
 extern int
 cifs_setup_volume_info(struct smb3_fs_context *ctx, const char *mntopts, const char *devname);
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 65d1a65bfc37..a8e41c1e80ca 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -42,10 +42,6 @@ static struct {
 	int index;
 	char *name;
 } protocols[] = {
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-	{LANMAN_PROT, "\2LM1.2X002"},
-	{LANMAN2_PROT, "\2LANMAN2.1"},
-#endif /* weak password hashing for legacy clients */
 	{CIFS_PROT, "\2NT LM 0.12"},
 	{POSIX_PROT, "\2POSIX 2"},
 	{BAD_PROT, "\2"}
@@ -55,10 +51,6 @@ static struct {
 	int index;
 	char *name;
 } protocols[] = {
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-	{LANMAN_PROT, "\2LM1.2X002"},
-	{LANMAN2_PROT, "\2LANMAN2.1"},
-#endif /* weak password hashing for legacy clients */
 	{CIFS_PROT, "\2NT LM 0.12"},
 	{BAD_PROT, "\2"}
 };
@@ -66,17 +58,9 @@ static struct {
 
 /* define the number of elements in the cifs dialect array */
 #ifdef CONFIG_CIFS_POSIX
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-#define CIFS_NUM_PROT 4
-#else
 #define CIFS_NUM_PROT 2
-#endif /* CIFS_WEAK_PW_HASH */
 #else /* not posix */
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-#define CIFS_NUM_PROT 3
-#else
 #define CIFS_NUM_PROT 1
-#endif /* CONFIG_CIFS_WEAK_PW_HASH */
 #endif /* CIFS_POSIX */
 
 /*
@@ -475,89 +459,6 @@ cifs_enable_signing(struct TCP_Server_Info *server, bool mnt_sign_required)
 	return 0;
 }
 
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-static int
-decode_lanman_negprot_rsp(struct TCP_Server_Info *server, NEGOTIATE_RSP *pSMBr)
-{
-	__s16 tmp;
-	struct lanman_neg_rsp *rsp = (struct lanman_neg_rsp *)pSMBr;
-
-	if (server->dialect != LANMAN_PROT && server->dialect != LANMAN2_PROT)
-		return -EOPNOTSUPP;
-
-	server->sec_mode = le16_to_cpu(rsp->SecurityMode);
-	server->maxReq = min_t(unsigned int,
-			       le16_to_cpu(rsp->MaxMpxCount),
-			       cifs_max_pending);
-	set_credits(server, server->maxReq);
-	server->maxBuf = le16_to_cpu(rsp->MaxBufSize);
-	/* set up max_read for readpages check */
-	server->max_read = server->maxBuf;
-	/* even though we do not use raw we might as well set this
-	accurately, in case we ever find a need for it */
-	if ((le16_to_cpu(rsp->RawMode) & RAW_ENABLE) == RAW_ENABLE) {
-		server->max_rw = 0xFF00;
-		server->capabilities = CAP_MPX_MODE | CAP_RAW_MODE;
-	} else {
-		server->max_rw = 0;/* do not need to use raw anyway */
-		server->capabilities = CAP_MPX_MODE;
-	}
-	tmp = (__s16)le16_to_cpu(rsp->ServerTimeZone);
-	if (tmp == -1) {
-		/* OS/2 often does not set timezone therefore
-		 * we must use server time to calc time zone.
-		 * Could deviate slightly from the right zone.
-		 * Smallest defined timezone difference is 15 minutes
-		 * (i.e. Nepal).  Rounding up/down is done to match
-		 * this requirement.
-		 */
-		int val, seconds, remain, result;
-		struct timespec64 ts;
-		time64_t utc = ktime_get_real_seconds();
-		ts = cnvrtDosUnixTm(rsp->SrvTime.Date,
-				    rsp->SrvTime.Time, 0);
-		cifs_dbg(FYI, "SrvTime %lld sec since 1970 (utc: %lld) diff: %lld\n",
-			 ts.tv_sec, utc,
-			 utc - ts.tv_sec);
-		val = (int)(utc - ts.tv_sec);
-		seconds = abs(val);
-		result = (seconds / MIN_TZ_ADJ) * MIN_TZ_ADJ;
-		remain = seconds % MIN_TZ_ADJ;
-		if (remain >= (MIN_TZ_ADJ / 2))
-			result += MIN_TZ_ADJ;
-		if (val < 0)
-			result = -result;
-		server->timeAdj = result;
-	} else {
-		server->timeAdj = (int)tmp;
-		server->timeAdj *= 60; /* also in seconds */
-	}
-	cifs_dbg(FYI, "server->timeAdj: %d seconds\n", server->timeAdj);
-
-
-	/* BB get server time for time conversions and add
-	code to use it and timezone since this is not UTC */
-
-	if (rsp->EncryptionKeyLength ==
-			cpu_to_le16(CIFS_CRYPTO_KEY_SIZE)) {
-		memcpy(server->cryptkey, rsp->EncryptionKey,
-			CIFS_CRYPTO_KEY_SIZE);
-	} else if (server->sec_mode & SECMODE_PW_ENCRYPT) {
-		return -EIO; /* need cryptkey unless plain text */
-	}
-
-	cifs_dbg(FYI, "LANMAN negotiated\n");
-	return 0;
-}
-#else
-static inline int
-decode_lanman_negprot_rsp(struct TCP_Server_Info *server, NEGOTIATE_RSP *pSMBr)
-{
-	cifs_dbg(VFS, "mount failed, cifs module not built with CIFS_WEAK_PW_HASH support\n");
-	return -EOPNOTSUPP;
-}
-#endif
-
 static bool
 should_set_ext_sec_flag(enum securityEnum sectype)
 {
@@ -626,16 +527,12 @@ CIFSSMBNegotiate(const unsigned int xid, struct cifs_ses *ses)
 	server->dialect = le16_to_cpu(pSMBr->DialectIndex);
 	cifs_dbg(FYI, "Dialect: %d\n", server->dialect);
 	/* Check wct = 1 error case */
-	if ((pSMBr->hdr.WordCount < 13) || (server->dialect == BAD_PROT)) {
+	if ((pSMBr->hdr.WordCount <= 13) || (server->dialect == BAD_PROT)) {
 		/* core returns wct = 1, but we do not ask for core - otherwise
 		small wct just comes when dialect index is -1 indicating we
 		could not negotiate a common dialect */
 		rc = -EOPNOTSUPP;
 		goto neg_err_exit;
-	} else if (pSMBr->hdr.WordCount == 13) {
-		server->negflavor = CIFS_NEGFLAVOR_LANMAN;
-		rc = decode_lanman_negprot_rsp(server, pSMBr);
-		goto signing_check;
 	} else if (pSMBr->hdr.WordCount != 17) {
 		/* unknown wct */
 		rc = -EOPNOTSUPP;
@@ -677,7 +574,6 @@ CIFSSMBNegotiate(const unsigned int xid, struct cifs_ses *ses)
 		server->capabilities &= ~CAP_EXTENDED_SECURITY;
 	}
 
-signing_check:
 	if (!rc)
 		rc = cifs_enable_signing(server, ses->sign);
 neg_err_exit:
@@ -2101,6 +1997,7 @@ cifs_writev_complete(struct work_struct *work)
 		else if (wdata->result < 0)
 			SetPageError(page);
 		end_page_writeback(page);
+		cifs_readpage_to_fscache(inode, page);
 		put_page(page);
 	}
 	if (wdata->result != -EAGAIN)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 3781eee9360a..0db344807ef1 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3684,38 +3684,6 @@ CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
 		*bcc_ptr = 0; /* password is null byte */
 		bcc_ptr++;              /* skip password */
 		/* already aligned so no need to do it below */
-	} else {
-		pSMB->PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
-		/* BB FIXME add code to fail this if NTLMv2 or Kerberos
-		   specified as required (when that support is added to
-		   the vfs in the future) as only NTLM or the much
-		   weaker LANMAN (which we do not send by default) is accepted
-		   by Samba (not sure whether other servers allow
-		   NTLMv2 password here) */
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-		if ((global_secflags & CIFSSEC_MAY_LANMAN) &&
-		    (ses->sectype == LANMAN))
-			calc_lanman_hash(tcon->password, ses->server->cryptkey,
-					 ses->server->sec_mode &
-					    SECMODE_PW_ENCRYPT ? true : false,
-					 bcc_ptr);
-		else
-#endif /* CIFS_WEAK_PW_HASH */
-		rc = SMBNTencrypt(tcon->password, ses->server->cryptkey,
-					bcc_ptr, nls_codepage);
-		if (rc) {
-			cifs_dbg(FYI, "%s Can't generate NTLM rsp. Error: %d\n",
-				 __func__, rc);
-			cifs_buf_release(smb_buffer);
-			return rc;
-		}
-
-		bcc_ptr += CIFS_AUTH_RESP_SIZE;
-		if (ses->capabilities & CAP_UNICODE) {
-			/* must align unicode strings */
-			*bcc_ptr = 0; /* null byte password */
-			bcc_ptr++;
-		}
 	}
 
 	if (ses->server->sign)
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index bb98fbdd22a9..d0216472f1c6 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -377,6 +377,8 @@ static void cifsFileInfo_put_final(struct cifsFileInfo *cifs_file)
 	struct cifsLockInfo *li, *tmp;
 	struct super_block *sb = inode->i_sb;
 
+	cifs_fscache_release_inode_cookie(inode);
+
 	/*
 	 * Delete any outstanding lock records. We'll lose them when the file
 	 * is closed anyway.
@@ -882,8 +884,10 @@ int cifs_close(struct inode *inode, struct file *file)
 		if ((cinode->oplock == CIFS_CACHE_RHW_FLG) &&
 		    cinode->lease_granted &&
 		    dclose) {
-			if (test_bit(CIFS_INO_MODIFIED_ATTR, &cinode->flags))
+			if (test_bit(CIFS_INO_MODIFIED_ATTR, &cinode->flags)) {
 				inode->i_ctime = inode->i_mtime = current_time(inode);
+				cifs_fscache_update_inode_cookie(inode);
+			}
 			spin_lock(&cinode->deferred_lock);
 			cifs_add_deferred_close(cfile, dclose);
 			if (cfile->deferred_close_scheduled &&
@@ -4170,6 +4174,10 @@ static vm_fault_t
 cifs_page_mkwrite(struct vm_fault *vmf)
 {
 	struct page *page = vmf->page;
+	struct file *file = vmf->vma->vm_file;
+	struct inode *inode = file_inode(file);
+
+	cifs_fscache_wait_on_page_write(inode, page);
 
 	lock_page(page);
 	return VM_FAULT_LOCKED;
@@ -4235,13 +4243,16 @@ cifs_readv_complete(struct work_struct *work)
 		    (rdata->result == -EAGAIN && got_bytes)) {
 			flush_dcache_page(page);
 			SetPageUptodate(page);
-		}
+		} else
+			SetPageError(page);
 
 		unlock_page(page);
 
 		if (rdata->result == 0 ||
 		    (rdata->result == -EAGAIN && got_bytes))
 			cifs_readpage_to_fscache(rdata->mapping->host, page);
+		else
+			cifs_fscache_uncache_page(rdata->mapping->host, page);
 
 		got_bytes -= min_t(unsigned int, PAGE_SIZE, got_bytes);
 
diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
index eed59bc1d913..3109def8e199 100644
--- a/fs/cifs/fs_context.c
+++ b/fs/cifs/fs_context.c
@@ -57,12 +57,9 @@ static const match_table_t cifs_secflavor_tokens = {
 	{ Opt_sec_krb5p, "krb5p" },
 	{ Opt_sec_ntlmsspi, "ntlmsspi" },
 	{ Opt_sec_ntlmssp, "ntlmssp" },
-	{ Opt_ntlm, "ntlm" },
-	{ Opt_sec_ntlmi, "ntlmi" },
 	{ Opt_sec_ntlmv2, "nontlm" },
 	{ Opt_sec_ntlmv2, "ntlmv2" },
 	{ Opt_sec_ntlmv2i, "ntlmv2i" },
-	{ Opt_sec_lanman, "lanman" },
 	{ Opt_sec_none, "none" },
 
 	{ Opt_sec_err, NULL }
@@ -221,23 +218,12 @@ cifs_parse_security_flavors(struct fs_context *fc, char *value, struct smb3_fs_c
 	case Opt_sec_ntlmssp:
 		ctx->sectype = RawNTLMSSP;
 		break;
-	case Opt_sec_ntlmi:
-		ctx->sign = true;
-		fallthrough;
-	case Opt_ntlm:
-		ctx->sectype = NTLM;
-		break;
 	case Opt_sec_ntlmv2i:
 		ctx->sign = true;
 		fallthrough;
 	case Opt_sec_ntlmv2:
 		ctx->sectype = NTLMv2;
 		break;
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-	case Opt_sec_lanman:
-		ctx->sectype = LANMAN;
-		break;
-#endif
 	case Opt_sec_none:
 		ctx->nullauth = 1;
 		break;
@@ -1266,10 +1252,17 @@ static int smb3_fs_context_parse_param(struct fs_context *fc,
 			ctx->posix_paths = 1;
 		break;
 	case Opt_unix:
-		if (result.negated)
+		if (result.negated) {
+			if (ctx->linux_ext == 1)
+				pr_warn_once("conflicting posix mount options specified\n");
 			ctx->linux_ext = 0;
-		else
 			ctx->no_linux_ext = 1;
+		} else {
+			if (ctx->no_linux_ext == 1)
+				pr_warn_once("conflicting posix mount options specified\n");
+			ctx->linux_ext = 1;
+			ctx->no_linux_ext = 0;
+		}
 		break;
 	case Opt_nocase:
 		ctx->nocase = 1;
diff --git a/fs/cifs/fs_context.h b/fs/cifs/fs_context.h
index b6243972edf3..a42ba71d7a81 100644
--- a/fs/cifs/fs_context.h
+++ b/fs/cifs/fs_context.h
@@ -47,11 +47,8 @@ enum cifs_sec_param {
 	Opt_sec_krb5p,
 	Opt_sec_ntlmsspi,
 	Opt_sec_ntlmssp,
-	Opt_ntlm,
-	Opt_sec_ntlmi,
 	Opt_sec_ntlmv2,
 	Opt_sec_ntlmv2i,
-	Opt_sec_lanman,
 	Opt_sec_none,
 
 	Opt_sec_err
diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c
index dd625033cd6b..fab47fa7df74 100644
--- a/fs/cifs/fscache.c
+++ b/fs/cifs/fscache.c
@@ -176,29 +176,34 @@ void cifs_fscache_release_inode_cookie(struct inode *inode)
 		auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
 
 		cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache);
+		/* fscache_relinquish_cookie does not seem to update auxdata */
+		fscache_update_cookie(cifsi->fscache, &auxdata);
 		fscache_relinquish_cookie(cifsi->fscache, &auxdata, false);
 		cifsi->fscache = NULL;
 	}
 }
 
-static void cifs_fscache_disable_inode_cookie(struct inode *inode)
+void cifs_fscache_update_inode_cookie(struct inode *inode)
 {
+	struct cifs_fscache_inode_auxdata auxdata;
 	struct cifsInodeInfo *cifsi = CIFS_I(inode);
 
 	if (cifsi->fscache) {
+		memset(&auxdata, 0, sizeof(auxdata));
+		auxdata.eof = cifsi->server_eof;
+		auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
+		auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
+		auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
+		auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
+
 		cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache);
-		fscache_uncache_all_inode_pages(cifsi->fscache, inode);
-		fscache_relinquish_cookie(cifsi->fscache, NULL, true);
-		cifsi->fscache = NULL;
+		fscache_update_cookie(cifsi->fscache, &auxdata);
 	}
 }
 
 void cifs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
 {
-	if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
-		cifs_fscache_disable_inode_cookie(inode);
-	else
-		cifs_fscache_enable_inode_cookie(inode);
+	cifs_fscache_enable_inode_cookie(inode);
 }
 
 void cifs_fscache_reset_inode_cookie(struct inode *inode)
@@ -310,6 +315,8 @@ void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
 	struct cifsInodeInfo *cifsi = CIFS_I(inode);
 	int ret;
 
+	WARN_ON(!cifsi->fscache);
+
 	cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n",
 		 __func__, cifsi->fscache, page, inode);
 	ret = fscache_write_page(cifsi->fscache, page,
@@ -334,3 +341,21 @@ void __cifs_fscache_invalidate_page(struct page *page, struct inode *inode)
 	fscache_wait_on_page_write(cookie, page);
 	fscache_uncache_page(cookie, page);
 }
+
+void __cifs_fscache_wait_on_page_write(struct inode *inode, struct page *page)
+{
+	struct cifsInodeInfo *cifsi = CIFS_I(inode);
+	struct fscache_cookie *cookie = cifsi->fscache;
+
+	cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", __func__, page, cookie);
+	fscache_wait_on_page_write(cookie, page);
+}
+
+void __cifs_fscache_uncache_page(struct inode *inode, struct page *page)
+{
+	struct cifsInodeInfo *cifsi = CIFS_I(inode);
+	struct fscache_cookie *cookie = cifsi->fscache;
+
+	cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", __func__, page, cookie);
+	fscache_uncache_page(cookie, page);
+}
diff --git a/fs/cifs/fscache.h b/fs/cifs/fscache.h
index 3d55cb2ef055..82e856b9cf89 100644
--- a/fs/cifs/fscache.h
+++ b/fs/cifs/fscache.h
@@ -55,10 +55,13 @@ extern void cifs_fscache_get_super_cookie(struct cifs_tcon *);
 extern void cifs_fscache_release_super_cookie(struct cifs_tcon *);
 
 extern void cifs_fscache_release_inode_cookie(struct inode *);
+extern void cifs_fscache_update_inode_cookie(struct inode *inode);
 extern void cifs_fscache_set_inode_cookie(struct inode *, struct file *);
 extern void cifs_fscache_reset_inode_cookie(struct inode *);
 
 extern void __cifs_fscache_invalidate_page(struct page *, struct inode *);
+extern void __cifs_fscache_wait_on_page_write(struct inode *inode, struct page *page);
+extern void __cifs_fscache_uncache_page(struct inode *inode, struct page *page);
 extern int cifs_fscache_release_page(struct page *page, gfp_t gfp);
 extern int __cifs_readpage_from_fscache(struct inode *, struct page *);
 extern int __cifs_readpages_from_fscache(struct inode *,
@@ -76,6 +79,20 @@ static inline void cifs_fscache_invalidate_page(struct page *page,
 		__cifs_fscache_invalidate_page(page, inode);
 }
 
+static inline void cifs_fscache_wait_on_page_write(struct inode *inode,
+						   struct page *page)
+{
+	if (PageFsCache(page))
+		__cifs_fscache_wait_on_page_write(inode, page);
+}
+
+static inline void cifs_fscache_uncache_page(struct inode *inode,
+						   struct page *page)
+{
+	if (PageFsCache(page))
+		__cifs_fscache_uncache_page(inode, page);
+}
+
 static inline int cifs_readpage_from_fscache(struct inode *inode,
 					     struct page *page)
 {
@@ -123,6 +140,7 @@ static inline void
 cifs_fscache_release_super_cookie(struct cifs_tcon *tcon) {}
 
 static inline void cifs_fscache_release_inode_cookie(struct inode *inode) {}
+static inline void cifs_fscache_update_inode_cookie(struct inode *inode) {}
 static inline void cifs_fscache_set_inode_cookie(struct inode *inode,
 						 struct file *filp) {}
 static inline void cifs_fscache_reset_inode_cookie(struct inode *inode) {}
@@ -133,6 +151,11 @@ static inline int cifs_fscache_release_page(struct page *page, gfp_t gfp)
 
 static inline void cifs_fscache_invalidate_page(struct page *page,
 			struct inode *inode) {}
+static inline void cifs_fscache_wait_on_page_write(struct inode *inode,
+						   struct page *page) {}
+static inline void cifs_fscache_uncache_page(struct inode *inode,
+						   struct page *page) {}
+
 static inline int
 cifs_readpage_from_fscache(struct inode *inode, struct page *page)
 {
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 65f8a70cece3..50c01cff4c84 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -2297,6 +2297,7 @@ cifs_revalidate_mapping(struct inode *inode)
 {
 	int rc;
 	unsigned long *flags = &CIFS_I(inode)->flags;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 
 	/* swapfiles are not supposed to be shared */
 	if (IS_SWAPFILE(inode))
@@ -2308,11 +2309,16 @@ cifs_revalidate_mapping(struct inode *inode)
 		return rc;
 
 	if (test_and_clear_bit(CIFS_INO_INVALID_MAPPING, flags)) {
+		/* for cache=singleclient, do not invalidate */
+		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RW_CACHE)
+			goto skip_invalidate;
+
 		rc = cifs_invalidate_mapping(inode);
 		if (rc)
 			set_bit(CIFS_INO_INVALID_MAPPING, flags);
 	}
 
+skip_invalidate:
 	clear_bit_unlock(CIFS_INO_LOCK, flags);
 	smp_mb__after_atomic();
 	wake_up_bit(flags, CIFS_INO_LOCK);
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index bfee176b901d..54d77c99e21c 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -369,7 +369,7 @@ int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
  */
 
 static int
-initiate_cifs_search(const unsigned int xid, struct file *file,
+_initiate_cifs_search(const unsigned int xid, struct file *file,
 		     const char *full_path)
 {
 	__u16 search_flags;
@@ -451,6 +451,27 @@ error_exit:
 	return rc;
 }
 
+static int
+initiate_cifs_search(const unsigned int xid, struct file *file,
+		     const char *full_path)
+{
+	int rc, retry_count = 0;
+
+	do {
+		rc = _initiate_cifs_search(xid, file, full_path);
+		/*
+		 * If we don't have enough credits to start reading the
+		 * directory just try again after short wait.
+		 */
+		if (rc != -EDEADLK)
+			break;
+
+		usleep_range(512, 2048);
+	} while (retry_count++ < 5);
+
+	return rc;
+}
+
 /* return length of unicode string in bytes */
 static int cifs_unicode_bytelen(const char *str)
 {
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index c5785fd3f52e..118403fbeda2 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -799,30 +799,16 @@ cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
 		}
 	case CIFS_NEGFLAVOR_UNENCAP:
 		switch (requested) {
-		case NTLM:
 		case NTLMv2:
 			return requested;
 		case Unspecified:
 			if (global_secflags & CIFSSEC_MAY_NTLMV2)
 				return NTLMv2;
-			if (global_secflags & CIFSSEC_MAY_NTLM)
-				return NTLM;
 			break;
 		default:
 			break;
 		}
-		fallthrough;	/* to attempt LANMAN authentication next */
-	case CIFS_NEGFLAVOR_LANMAN:
-		switch (requested) {
-		case LANMAN:
-			return requested;
-		case Unspecified:
-			if (global_secflags & CIFSSEC_MAY_LANMAN)
-				return LANMAN;
-			fallthrough;
-		default:
-			return Unspecified;
-		}
+		fallthrough;
 	default:
 		return Unspecified;
 	}
@@ -877,7 +863,7 @@ sess_alloc_buffer(struct sess_data *sess_data, int wct)
 	return 0;
 
 out_free_smb_buf:
-	kfree(smb_buf);
+	cifs_small_buf_release(smb_buf);
 	sess_data->iov[0].iov_base = NULL;
 	sess_data->iov[0].iov_len = 0;
 	sess_data->buf0_type = CIFS_NO_BUFFER;
@@ -947,230 +933,6 @@ sess_sendreceive(struct sess_data *sess_data)
 	return rc;
 }
 
-/*
- * LANMAN and plaintext are less secure and off by default.
- * So we make this explicitly be turned on in kconfig (in the
- * build) and turned on at runtime (changed from the default)
- * in proc/fs/cifs or via mount parm.  Unfortunately this is
- * needed for old Win (e.g. Win95), some obscure NAS and OS/2
- */
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-static void
-sess_auth_lanman(struct sess_data *sess_data)
-{
-	int rc = 0;
-	struct smb_hdr *smb_buf;
-	SESSION_SETUP_ANDX *pSMB;
-	char *bcc_ptr;
-	struct cifs_ses *ses = sess_data->ses;
-	char lnm_session_key[CIFS_AUTH_RESP_SIZE];
-	__u16 bytes_remaining;
-
-	/* lanman 2 style sessionsetup */
-	/* wct = 10 */
-	rc = sess_alloc_buffer(sess_data, 10);
-	if (rc)
-		goto out;
-
-	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
-	bcc_ptr = sess_data->iov[2].iov_base;
-	(void)cifs_ssetup_hdr(ses, pSMB);
-
-	pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
-
-	if (ses->user_name != NULL) {
-		/* no capabilities flags in old lanman negotiation */
-		pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
-
-		/* Calculate hash with password and copy into bcc_ptr.
-		 * Encryption Key (stored as in cryptkey) gets used if the
-		 * security mode bit in Negotiate Protocol response states
-		 * to use challenge/response method (i.e. Password bit is 1).
-		 */
-		rc = calc_lanman_hash(ses->password, ses->server->cryptkey,
-				      ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
-				      true : false, lnm_session_key);
-		if (rc)
-			goto out;
-
-		memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
-		bcc_ptr += CIFS_AUTH_RESP_SIZE;
-	} else {
-		pSMB->old_req.PasswordLength = 0;
-	}
-
-	/*
-	 * can not sign if LANMAN negotiated so no need
-	 * to calculate signing key? but what if server
-	 * changed to do higher than lanman dialect and
-	 * we reconnected would we ever calc signing_key?
-	 */
-
-	cifs_dbg(FYI, "Negotiating LANMAN setting up strings\n");
-	/* Unicode not allowed for LANMAN dialects */
-	ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
-
-	sess_data->iov[2].iov_len = (long) bcc_ptr -
-			(long) sess_data->iov[2].iov_base;
-
-	rc = sess_sendreceive(sess_data);
-	if (rc)
-		goto out;
-
-	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
-	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
-
-	/* lanman response has a word count of 3 */
-	if (smb_buf->WordCount != 3) {
-		rc = -EIO;
-		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
-		goto out;
-	}
-
-	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
-		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
-
-	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
-	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
-
-	bytes_remaining = get_bcc(smb_buf);
-	bcc_ptr = pByteArea(smb_buf);
-
-	/* BB check if Unicode and decode strings */
-	if (bytes_remaining == 0) {
-		/* no string area to decode, do nothing */
-	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
-		/* unicode string area must be word-aligned */
-		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
-			++bcc_ptr;
-			--bytes_remaining;
-		}
-		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
-				      sess_data->nls_cp);
-	} else {
-		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
-				    sess_data->nls_cp);
-	}
-
-	rc = sess_establish_session(sess_data);
-out:
-	sess_data->result = rc;
-	sess_data->func = NULL;
-	sess_free_buffer(sess_data);
-}
-
-#endif
-
-static void
-sess_auth_ntlm(struct sess_data *sess_data)
-{
-	int rc = 0;
-	struct smb_hdr *smb_buf;
-	SESSION_SETUP_ANDX *pSMB;
-	char *bcc_ptr;
-	struct cifs_ses *ses = sess_data->ses;
-	__u32 capabilities;
-	__u16 bytes_remaining;
-
-	/* old style NTLM sessionsetup */
-	/* wct = 13 */
-	rc = sess_alloc_buffer(sess_data, 13);
-	if (rc)
-		goto out;
-
-	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
-	bcc_ptr = sess_data->iov[2].iov_base;
-	capabilities = cifs_ssetup_hdr(ses, pSMB);
-
-	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
-	if (ses->user_name != NULL) {
-		pSMB->req_no_secext.CaseInsensitivePasswordLength =
-				cpu_to_le16(CIFS_AUTH_RESP_SIZE);
-		pSMB->req_no_secext.CaseSensitivePasswordLength =
-				cpu_to_le16(CIFS_AUTH_RESP_SIZE);
-
-		/* calculate ntlm response and session key */
-		rc = setup_ntlm_response(ses, sess_data->nls_cp);
-		if (rc) {
-			cifs_dbg(VFS, "Error %d during NTLM authentication\n",
-					 rc);
-			goto out;
-		}
-
-		/* copy ntlm response */
-		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
-				CIFS_AUTH_RESP_SIZE);
-		bcc_ptr += CIFS_AUTH_RESP_SIZE;
-		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
-				CIFS_AUTH_RESP_SIZE);
-		bcc_ptr += CIFS_AUTH_RESP_SIZE;
-	} else {
-		pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
-		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
-	}
-
-	if (ses->capabilities & CAP_UNICODE) {
-		/* unicode strings must be word aligned */
-		if (sess_data->iov[0].iov_len % 2) {
-			*bcc_ptr = 0;
-			bcc_ptr++;
-		}
-		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
-	} else {
-		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
-	}
-
-
-	sess_data->iov[2].iov_len = (long) bcc_ptr -
-			(long) sess_data->iov[2].iov_base;
-
-	rc = sess_sendreceive(sess_data);
-	if (rc)
-		goto out;
-
-	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
-	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
-
-	if (smb_buf->WordCount != 3) {
-		rc = -EIO;
-		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
-		goto out;
-	}
-
-	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
-		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
-
-	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
-	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
-
-	bytes_remaining = get_bcc(smb_buf);
-	bcc_ptr = pByteArea(smb_buf);
-
-	/* BB check if Unicode and decode strings */
-	if (bytes_remaining == 0) {
-		/* no string area to decode, do nothing */
-	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
-		/* unicode string area must be word-aligned */
-		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
-			++bcc_ptr;
-			--bytes_remaining;
-		}
-		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
-				      sess_data->nls_cp);
-	} else {
-		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
-				    sess_data->nls_cp);
-	}
-
-	rc = sess_establish_session(sess_data);
-out:
-	sess_data->result = rc;
-	sess_data->func = NULL;
-	sess_free_buffer(sess_data);
-	kfree(ses->auth_key.response);
-	ses->auth_key.response = NULL;
-}
-
 static void
 sess_auth_ntlmv2(struct sess_data *sess_data)
 {
@@ -1675,21 +1437,6 @@ static int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
 	}
 
 	switch (type) {
-	case LANMAN:
-		/* LANMAN and plaintext are less secure and off by default.
-		 * So we make this explicitly be turned on in kconfig (in the
-		 * build) and turned on at runtime (changed from the default)
-		 * in proc/fs/cifs or via mount parm.  Unfortunately this is
-		 * needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-		sess_data->func = sess_auth_lanman;
-		break;
-#else
-		return -EOPNOTSUPP;
-#endif
-	case NTLM:
-		sess_data->func = sess_auth_ntlm;
-		break;
 	case NTLMv2:
 		sess_data->func = sess_auth_ntlmv2;
 		break;
diff --git a/fs/cifs/smb2maperror.c b/fs/cifs/smb2maperror.c
index cea39bcecbab..181514b8770d 100644
--- a/fs/cifs/smb2maperror.c
+++ b/fs/cifs/smb2maperror.c
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: LGPL-2.1
 /*
- *   fs/smb2/smb2maperror.c
  *
  *   Functions which do error mapping of SMB2 status codes to POSIX errors
  *
diff --git a/fs/cifs/smbencrypt.c b/fs/cifs/smbencrypt.c
index 39a938443e3e..10047cc55286 100644
--- a/fs/cifs/smbencrypt.c
+++ b/fs/cifs/smbencrypt.c
@@ -18,13 +18,13 @@
 #include <linux/string.h>
 #include <linux/kernel.h>
 #include <linux/random.h>
-#include <crypto/des.h>
 #include "cifs_fs_sb.h"
 #include "cifs_unicode.h"
 #include "cifspdu.h"
 #include "cifsglob.h"
 #include "cifs_debug.h"
 #include "cifsproto.h"
+#include "../cifs_common/md4.h"
 
 #ifndef false
 #define false 0
@@ -38,126 +38,29 @@
 #define SSVALX(buf,pos,val) (CVAL(buf,pos)=(val)&0xFF,CVAL(buf,pos+1)=(val)>>8)
 #define SSVAL(buf,pos,val) SSVALX((buf),(pos),((__u16)(val)))
 
-static void
-str_to_key(unsigned char *str, unsigned char *key)
-{
-	int i;
-
-	key[0] = str[0] >> 1;
-	key[1] = ((str[0] & 0x01) << 6) | (str[1] >> 2);
-	key[2] = ((str[1] & 0x03) << 5) | (str[2] >> 3);
-	key[3] = ((str[2] & 0x07) << 4) | (str[3] >> 4);
-	key[4] = ((str[3] & 0x0F) << 3) | (str[4] >> 5);
-	key[5] = ((str[4] & 0x1F) << 2) | (str[5] >> 6);
-	key[6] = ((str[5] & 0x3F) << 1) | (str[6] >> 7);
-	key[7] = str[6] & 0x7F;
-	for (i = 0; i < 8; i++)
-		key[i] = (key[i] << 1);
-}
-
-static int
-smbhash(unsigned char *out, const unsigned char *in, unsigned char *key)
-{
-	unsigned char key2[8];
-	struct des_ctx ctx;
-
-	str_to_key(key, key2);
-
-	if (fips_enabled) {
-		cifs_dbg(VFS, "FIPS compliance enabled: DES not permitted\n");
-		return -ENOENT;
-	}
-
-	des_expand_key(&ctx, key2, DES_KEY_SIZE);
-	des_encrypt(&ctx, out, in);
-	memzero_explicit(&ctx, sizeof(ctx));
-
-	return 0;
-}
-
-static int
-E_P16(unsigned char *p14, unsigned char *p16)
-{
-	int rc;
-	unsigned char sp8[8] =
-	    { 0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25 };
-
-	rc = smbhash(p16, sp8, p14);
-	if (rc)
-		return rc;
-	rc = smbhash(p16 + 8, sp8, p14 + 7);
-	return rc;
-}
-
-static int
-E_P24(unsigned char *p21, const unsigned char *c8, unsigned char *p24)
-{
-	int rc;
-
-	rc = smbhash(p24, c8, p21);
-	if (rc)
-		return rc;
-	rc = smbhash(p24 + 8, c8, p21 + 7);
-	if (rc)
-		return rc;
-	rc = smbhash(p24 + 16, c8, p21 + 14);
-	return rc;
-}
-
 /* produce a md4 message digest from data of length n bytes */
-int
+static int
 mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
 {
 	int rc;
-	struct crypto_shash *md4 = NULL;
-	struct sdesc *sdescmd4 = NULL;
-
-	rc = cifs_alloc_hash("md4", &md4, &sdescmd4);
-	if (rc)
-		goto mdfour_err;
+	struct md4_ctx mctx;
 
-	rc = crypto_shash_init(&sdescmd4->shash);
+	rc = cifs_md4_init(&mctx);
 	if (rc) {
-		cifs_dbg(VFS, "%s: Could not init md4 shash\n", __func__);
+		cifs_dbg(VFS, "%s: Could not init MD4\n", __func__);
 		goto mdfour_err;
 	}
-	rc = crypto_shash_update(&sdescmd4->shash, link_str, link_len);
+	rc = cifs_md4_update(&mctx, link_str, link_len);
 	if (rc) {
-		cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__);
+		cifs_dbg(VFS, "%s: Could not update MD4\n", __func__);
 		goto mdfour_err;
 	}
-	rc = crypto_shash_final(&sdescmd4->shash, md4_hash);
+	rc = cifs_md4_final(&mctx, md4_hash);
 	if (rc)
-		cifs_dbg(VFS, "%s: Could not generate md4 hash\n", __func__);
-
-mdfour_err:
-	cifs_free_hash(&md4, &sdescmd4);
-	return rc;
-}
-
-/*
-   This implements the X/Open SMB password encryption
-   It takes a password, a 8 byte "crypt key" and puts 24 bytes of
-   encrypted password into p24 */
-/* Note that password must be uppercased and null terminated */
-int
-SMBencrypt(unsigned char *passwd, const unsigned char *c8, unsigned char *p24)
-{
-	int rc;
-	unsigned char p14[14], p16[16], p21[21];
+		cifs_dbg(VFS, "%s: Could not finalize MD4\n", __func__);
 
-	memset(p14, '\0', 14);
-	memset(p16, '\0', 16);
-	memset(p21, '\0', 21);
-
-	memcpy(p14, passwd, 14);
-	rc = E_P16(p14, p16);
-	if (rc)
-		return rc;
-
-	memcpy(p21, p16, 16);
-	rc = E_P24(p21, c8, p24);
 
+mdfour_err:
 	return rc;
 }
 
@@ -186,25 +89,3 @@ E_md4hash(const unsigned char *passwd, unsigned char *p16,
 
 	return rc;
 }
-
-/* Does the NT MD4 hash then des encryption. */
-int
-SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24,
-		const struct nls_table *codepage)
-{
-	int rc;
-	unsigned char p16[16], p21[21];
-
-	memset(p16, '\0', 16);
-	memset(p21, '\0', 21);
-
-	rc = E_md4hash(passwd, p16, codepage);
-	if (rc) {
-		cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
-			 __func__, rc);
-		return rc;
-	}
-	memcpy(p21, p16, 16);
-	rc = E_P24(p21, c8, p24);
-	return rc;
-}
diff --git a/fs/cifs_common/Makefile b/fs/cifs_common/Makefile
new file mode 100644
index 000000000000..6fedd2f88a25
--- /dev/null
+++ b/fs/cifs_common/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for Linux filesystem routines that are shared by client and server.
+#
+
+obj-$(CONFIG_CIFS_COMMON) += cifs_arc4.o
+obj-$(CONFIG_CIFS_COMMON) += cifs_md4.o
diff --git a/fs/cifs_common/arc4.h b/fs/cifs_common/arc4.h
new file mode 100644
index 000000000000..12e71ec033a1
--- /dev/null
+++ b/fs/cifs_common/arc4.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Common values for ARC4 Cipher Algorithm
+ */
+
+#ifndef _CRYPTO_ARC4_H
+#define _CRYPTO_ARC4_H
+
+#include <linux/types.h>
+
+#define ARC4_MIN_KEY_SIZE	1
+#define ARC4_MAX_KEY_SIZE	256
+#define ARC4_BLOCK_SIZE		1
+
+struct arc4_ctx {
+	u32 S[256];
+	u32 x, y;
+};
+
+int cifs_arc4_setkey(struct arc4_ctx *ctx, const u8 *in_key, unsigned int key_len);
+void cifs_arc4_crypt(struct arc4_ctx *ctx, u8 *out, const u8 *in, unsigned int len);
+
+#endif /* _CRYPTO_ARC4_H */
diff --git a/fs/cifs_common/cifs_arc4.c b/fs/cifs_common/cifs_arc4.c
new file mode 100644
index 000000000000..b964cc682944
--- /dev/null
+++ b/fs/cifs_common/cifs_arc4.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Cryptographic API
+ *
+ * ARC4 Cipher Algorithm
+ *
+ * Jon Oberheide <jon@oberheide.org>
+ */
+
+#include <linux/module.h>
+#include "arc4.h"
+
+MODULE_LICENSE("GPL");
+
+int cifs_arc4_setkey(struct arc4_ctx *ctx, const u8 *in_key, unsigned int key_len)
+{
+	int i, j = 0, k = 0;
+
+	ctx->x = 1;
+	ctx->y = 0;
+
+	for (i = 0; i < 256; i++)
+		ctx->S[i] = i;
+
+	for (i = 0; i < 256; i++) {
+		u32 a = ctx->S[i];
+
+		j = (j + in_key[k] + a) & 0xff;
+		ctx->S[i] = ctx->S[j];
+		ctx->S[j] = a;
+		if (++k >= key_len)
+			k = 0;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cifs_arc4_setkey);
+
+void cifs_arc4_crypt(struct arc4_ctx *ctx, u8 *out, const u8 *in, unsigned int len)
+{
+	u32 *const S = ctx->S;
+	u32 x, y, a, b;
+	u32 ty, ta, tb;
+
+	if (len == 0)
+		return;
+
+	x = ctx->x;
+	y = ctx->y;
+
+	a = S[x];
+	y = (y + a) & 0xff;
+	b = S[y];
+
+	do {
+		S[y] = a;
+		a = (a + b) & 0xff;
+		S[x] = b;
+		x = (x + 1) & 0xff;
+		ta = S[x];
+		ty = (y + ta) & 0xff;
+		tb = S[ty];
+		*out++ = *in++ ^ S[a];
+		if (--len == 0)
+			break;
+		y = ty;
+		a = ta;
+		b = tb;
+	} while (true);
+
+	ctx->x = x;
+	ctx->y = y;
+}
+EXPORT_SYMBOL_GPL(cifs_arc4_crypt);
+
+static int __init
+init_cifs_common(void)
+{
+	return 0;
+}
+static void __init
+exit_cifs_common(void)
+{
+}
+
+module_init(init_cifs_common)
+module_exit(exit_cifs_common)
diff --git a/fs/cifs_common/cifs_md4.c b/fs/cifs_common/cifs_md4.c
new file mode 100644
index 000000000000..50f78cfc6ce9
--- /dev/null
+++ b/fs/cifs_common/cifs_md4.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cryptographic API.
+ *
+ * MD4 Message Digest Algorithm (RFC1320).
+ *
+ * Implementation derived from Andrew Tridgell and Steve French's
+ * CIFS MD4 implementation, and the cryptoapi implementation
+ * originally based on the public domain implementation written
+ * by Colin Plumb in 1993.
+ *
+ * Copyright (c) Andrew Tridgell 1997-1998.
+ * Modified by Steve French (sfrench@us.ibm.com) 2002
+ * Copyright (c) Cryptoapi developers.
+ * Copyright (c) 2002 David S. Miller (davem@redhat.com)
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ *
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <asm/byteorder.h>
+#include "md4.h"
+
+MODULE_LICENSE("GPL");
+
+static inline u32 lshift(u32 x, unsigned int s)
+{
+	x &= 0xFFFFFFFF;
+	return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
+}
+
+static inline u32 F(u32 x, u32 y, u32 z)
+{
+	return (x & y) | ((~x) & z);
+}
+
+static inline u32 G(u32 x, u32 y, u32 z)
+{
+	return (x & y) | (x & z) | (y & z);
+}
+
+static inline u32 H(u32 x, u32 y, u32 z)
+{
+	return x ^ y ^ z;
+}
+
+#define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s))
+#define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s))
+#define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s))
+
+static void md4_transform(u32 *hash, u32 const *in)
+{
+	u32 a, b, c, d;
+
+	a = hash[0];
+	b = hash[1];
+	c = hash[2];
+	d = hash[3];
+
+	ROUND1(a, b, c, d, in[0], 3);
+	ROUND1(d, a, b, c, in[1], 7);
+	ROUND1(c, d, a, b, in[2], 11);
+	ROUND1(b, c, d, a, in[3], 19);
+	ROUND1(a, b, c, d, in[4], 3);
+	ROUND1(d, a, b, c, in[5], 7);
+	ROUND1(c, d, a, b, in[6], 11);
+	ROUND1(b, c, d, a, in[7], 19);
+	ROUND1(a, b, c, d, in[8], 3);
+	ROUND1(d, a, b, c, in[9], 7);
+	ROUND1(c, d, a, b, in[10], 11);
+	ROUND1(b, c, d, a, in[11], 19);
+	ROUND1(a, b, c, d, in[12], 3);
+	ROUND1(d, a, b, c, in[13], 7);
+	ROUND1(c, d, a, b, in[14], 11);
+	ROUND1(b, c, d, a, in[15], 19);
+
+	ROUND2(a, b, c, d, in[0], 3);
+	ROUND2(d, a, b, c, in[4], 5);
+	ROUND2(c, d, a, b, in[8], 9);
+	ROUND2(b, c, d, a, in[12], 13);
+	ROUND2(a, b, c, d, in[1], 3);
+	ROUND2(d, a, b, c, in[5], 5);
+	ROUND2(c, d, a, b, in[9], 9);
+	ROUND2(b, c, d, a, in[13], 13);
+	ROUND2(a, b, c, d, in[2], 3);
+	ROUND2(d, a, b, c, in[6], 5);
+	ROUND2(c, d, a, b, in[10], 9);
+	ROUND2(b, c, d, a, in[14], 13);
+	ROUND2(a, b, c, d, in[3], 3);
+	ROUND2(d, a, b, c, in[7], 5);
+	ROUND2(c, d, a, b, in[11], 9);
+	ROUND2(b, c, d, a, in[15], 13);
+
+	ROUND3(a, b, c, d, in[0], 3);
+	ROUND3(d, a, b, c, in[8], 9);
+	ROUND3(c, d, a, b, in[4], 11);
+	ROUND3(b, c, d, a, in[12], 15);
+	ROUND3(a, b, c, d, in[2], 3);
+	ROUND3(d, a, b, c, in[10], 9);
+	ROUND3(c, d, a, b, in[6], 11);
+	ROUND3(b, c, d, a, in[14], 15);
+	ROUND3(a, b, c, d, in[1], 3);
+	ROUND3(d, a, b, c, in[9], 9);
+	ROUND3(c, d, a, b, in[5], 11);
+	ROUND3(b, c, d, a, in[13], 15);
+	ROUND3(a, b, c, d, in[3], 3);
+	ROUND3(d, a, b, c, in[11], 9);
+	ROUND3(c, d, a, b, in[7], 11);
+	ROUND3(b, c, d, a, in[15], 15);
+
+	hash[0] += a;
+	hash[1] += b;
+	hash[2] += c;
+	hash[3] += d;
+}
+
+static inline void md4_transform_helper(struct md4_ctx *ctx)
+{
+	le32_to_cpu_array(ctx->block, ARRAY_SIZE(ctx->block));
+	md4_transform(ctx->hash, ctx->block);
+}
+
+int cifs_md4_init(struct md4_ctx *mctx)
+{
+	memset(mctx, 0, sizeof(struct md4_ctx));
+	mctx->hash[0] = 0x67452301;
+	mctx->hash[1] = 0xefcdab89;
+	mctx->hash[2] = 0x98badcfe;
+	mctx->hash[3] = 0x10325476;
+	mctx->byte_count = 0;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cifs_md4_init);
+
+int cifs_md4_update(struct md4_ctx *mctx, const u8 *data, unsigned int len)
+{
+	const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
+
+	mctx->byte_count += len;
+
+	if (avail > len) {
+		memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
+		       data, len);
+		return 0;
+	}
+
+	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
+	       data, avail);
+
+	md4_transform_helper(mctx);
+	data += avail;
+	len -= avail;
+
+	while (len >= sizeof(mctx->block)) {
+		memcpy(mctx->block, data, sizeof(mctx->block));
+		md4_transform_helper(mctx);
+		data += sizeof(mctx->block);
+		len -= sizeof(mctx->block);
+	}
+
+	memcpy(mctx->block, data, len);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cifs_md4_update);
+
+int cifs_md4_final(struct md4_ctx *mctx, u8 *out)
+{
+	const unsigned int offset = mctx->byte_count & 0x3f;
+	char *p = (char *)mctx->block + offset;
+	int padding = 56 - (offset + 1);
+
+	*p++ = 0x80;
+	if (padding < 0) {
+		memset(p, 0x00, padding + sizeof(u64));
+		md4_transform_helper(mctx);
+		p = (char *)mctx->block;
+		padding = 56;
+	}
+
+	memset(p, 0, padding);
+	mctx->block[14] = mctx->byte_count << 3;
+	mctx->block[15] = mctx->byte_count >> 29;
+	le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
+			  sizeof(u64)) / sizeof(u32));
+	md4_transform(mctx->hash, mctx->block);
+	cpu_to_le32_array(mctx->hash, ARRAY_SIZE(mctx->hash));
+	memcpy(out, mctx->hash, sizeof(mctx->hash));
+	memset(mctx, 0, sizeof(*mctx));
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cifs_md4_final);
diff --git a/fs/cifs_common/md4.h b/fs/cifs_common/md4.h
new file mode 100644
index 000000000000..5337becc699a
--- /dev/null
+++ b/fs/cifs_common/md4.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Common values for ARC4 Cipher Algorithm
+ */
+
+#ifndef _CIFS_MD4_H
+#define _CIFS_MD4_H
+
+#include <linux/types.h>
+
+#define MD4_DIGEST_SIZE		16
+#define MD4_HMAC_BLOCK_SIZE	64
+#define MD4_BLOCK_WORDS		16
+#define MD4_HASH_WORDS		4
+
+struct md4_ctx {
+	u32 hash[MD4_HASH_WORDS];
+	u32 block[MD4_BLOCK_WORDS];
+	u64 byte_count;
+};
+
+
+int cifs_md4_init(struct md4_ctx *mctx);
+int cifs_md4_update(struct md4_ctx *mctx, const u8 *data, unsigned int len);
+int cifs_md4_final(struct md4_ctx *mctx, u8 *out);
+
+#endif /* _CIFS_MD4_H */