From: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Date: Tue, 23 Aug 2022 20:52:02 +0800
Subject: [PATCH] cifs: Add helper function to check smb1+ server
Git-commit: d291e703f420d5f8f999fe54f360d54d213bddb4
References: bsc#1190317
Patch-mainline: v6.0-rc3

SMB1 server's header_preamble_size is not 0, add use is_smb1 function
to simplify the code, no actual functional changes.

Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
 fs/cifs/cifsencrypt.c |    3 +--
 fs/cifs/cifsglob.h    |    5 +++++
 fs/cifs/connect.c     |   10 +++++-----
 fs/cifs/transport.c   |    4 ++--
 4 files changed, 13 insertions(+), 9 deletions(-)

--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -44,10 +44,9 @@ int __cifs_calc_signature(struct smb_rqs
 	int rc;
 	struct kvec *iov = rqst->rq_iov;
 	int n_vec = rqst->rq_nvec;
-	bool is_smb2 = HEADER_PREAMBLE_SIZE(server) == 0;
 
 	/* iov[0] is actual data and not the rfc1002 length for SMB2+ */
-	if (is_smb2) {
+	if (!is_smb1(server)) {
 		if (iov[0].iov_len <= 4)
 			return -EIO;
 		i = 0;
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -807,6 +807,11 @@ struct TCP_Server_Info {
 #endif
 };
 
+static inline bool is_smb1(struct TCP_Server_Info *server)
+{
+	return HEADER_PREAMBLE_SIZE(server) != 0;
+}
+
 struct cifs_credits {
 	unsigned int value;
 	unsigned int instance;
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -996,7 +996,7 @@ smb2_get_credits_from_hdr(char *buffer,
 	/*
 	 * SMB1 does not use credits.
 	 */
-	if (HEADER_PREAMBLE_SIZE(server))
+	if (is_smb1(server))
 		return 0;
 
 	return le16_to_cpu(shdr->CreditRequest);
@@ -1199,7 +1199,7 @@ smb2_add_credits_from_hdr(char *buffer,
 	/*
 	 * SMB1 does not use credits.
 	 */
-	if (HEADER_PREAMBLE_SIZE(server))
+	if (is_smb1(server))
 		return;
 
 	if (shdr->CreditRequest) {
@@ -1255,10 +1255,10 @@ cifs_demultiplex_thread(void *p)
 		if (length < 0)
 			continue;
 
-		if (HEADER_PREAMBLE_SIZE(server) == 0)
-			server->total_read = 0;
-		else
+		if (is_smb1(server))
 			server->total_read = length;
+		else
+			server->total_read = 0;
 
 		/*
 		 * The right amount was read from socket - 4 bytes,
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -271,7 +271,7 @@ smb_rqst_len(struct TCP_Server_Info *ser
 	int nvec;
 	unsigned long buflen = 0;
 
-	if (HEADER_PREAMBLE_SIZE(server) == 0 && rqst->rq_nvec >= 2 &&
+	if (!is_smb1(server) && rqst->rq_nvec >= 2 &&
 	    rqst->rq_iov[0].iov_len == 4) {
 		iov = &rqst->rq_iov[1];
 		nvec = rqst->rq_nvec - 1;
@@ -358,7 +358,7 @@ __smb_send_rqst(struct TCP_Server_Info *
 	sigprocmask(SIG_BLOCK, &mask, &oldmask);
 
 	/* Generate a rfc1002 marker for SMB2+ */
-	if (HEADER_PREAMBLE_SIZE(server) == 0) {
+	if (!is_smb1(server)) {
 		struct kvec hiov = {
 			.iov_base = &rfc1002_marker,
 			.iov_len  = 4