From: Aurelien Aptel <aaptel@suse.com>
Date: Fri, 21 May 2021 17:19:27 +0200
Subject: [PATCH] cifs: set server->cipher_type to AES-128-CCM for SMB3.0
Git-commit: 6d2fcfe6b517fe7cbf2687adfb0a16cdcd5d9243
References: bsc#1190317
Patch-mainline: v5.13-rc4
SMB3.0 doesn't have encryption negotiate context but simply uses
the SMB2_GLOBAL_CAP_ENCRYPTION flag.
When that flag is present in the neg response cifs.ko uses AES-128-CCM
which is the only cipher available in this context.
cipher_type was set to the server cipher only when parsing encryption
negotiate context (SMB3.1.1).
For SMB3.0 it was set to 0. This means cipher_type value can be 0 or 1
for AES-128-CCM.
Fix this by checking for SMB3.0 and encryption capability and setting
cipher_type appropriately.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
fs/cifs/smb2pdu.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 9f24eb88297a..c205f93e0a10 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -958,6 +958,13 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
/* Internal types */
server->capabilities |= SMB2_NT_FIND | SMB2_LARGE_FILES;
+ /*
+ * SMB3.0 supports only 1 cipher and doesn't have a encryption neg context
+ * Set the cipher type manually.
+ */
+ if (server->dialect == SMB30_PROT_ID && (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION))
+ server->cipher_type = SMB2_ENCRYPTION_AES128_CCM;
+
security_blob = smb2_get_data_area_len(&blob_offset, &blob_length,
(struct smb2_sync_hdr *)rsp);
/*
--
2.33.0