From: Ronnie Sahlberg <lsahlber@redhat.com>
Date: Wed, 22 Aug 2018 12:19:24 +1000
Subject: [PATCH] cifs: check if SMB2 PDU size has been padded and suppress the
warning
Git-commit: e6c47dd0da1e3a484e778046fc10da0b20606a86
Patch-mainline: v4.19-rc1
References: bsc#1144333
Some SMB2/3 servers, Win2016 but possibly others too, adds padding
not only between PDUs in a compound but also to the final PDU.
This padding extends the PDU to a multiple of 8 bytes.
Check if the unexpected length looks like this might be the case
and avoid triggering the log messages for :
"SMB2 server sent bad RFC1001 len %d not %d\n"
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Aurelien Aptel <aaptel@suse.com>
---
fs/cifs/smb2misc.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 303d4592ebe7..db0453660ff6 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -237,6 +237,13 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
if (clc_len == len + 1)
return 0;
+ /*
+ * Some windows servers (win2016) will pad also the final
+ * PDU in a compound to 8 bytes.
+ */
+ if (((clc_len + 7) & ~7) == len)
+ return 0;
+
/*
* MacOS server pads after SMB2.1 write response with 3 bytes
* of junk. Other servers match RFC1001 len to actual
--
2.16.4