ksmbd: set unique value to volume serial field in FS_VOLUME_INFORMATION

Steve French reported ksmbd set fixed value to volume serial field in
FS_VOLUME_INFORMATION. Volume serial value needs to be set to a unique
value for client fscache. This patch set crc value that is generated
with share name, path name and netbios name to volume serial.

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org # v5.15
Reported-by: Steve French <smfrench@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/ksmbd/Kconfig b/fs/ksmbd/Kconfig
index b83cbd7..6af339c 100644 (file)
--- a/fs/ksmbd/Kconfig
+++ b/fs/ksmbd/Kconfig
@@ -19,6 +19,7 @@ config SMB_SERVER
        select CRYPTO_GCM
        select ASN1
        select OID_REGISTRY
+       select CRC32
        default n
        help
          Choose Y here if you want to allow SMB3 compliant clients

diff --git a/fs/ksmbd/server.c b/fs/ksmbd/server.c
index 2a2b213..36d368e 100644 (file)
--- a/fs/ksmbd/server.c
+++ b/fs/ksmbd/server.c
@@ -632,5 +632,6 @@ MODULE_SOFTDEP("pre: sha512");
 MODULE_SOFTDEP("pre: aead2");
 MODULE_SOFTDEP("pre: ccm");
 MODULE_SOFTDEP("pre: gcm");
+MODULE_SOFTDEP("pre: crc32");
 module_init(ksmbd_server_init)
 module_exit(ksmbd_server_exit)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index a925e0f..04f82b5 100644 (file)
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -4892,11 +4892,18 @@ static int smb2_get_info_filesystem(struct ksmbd_work *work,
        {
                struct filesystem_vol_info *info;
                size_t sz;
+               unsigned int serial_crc = 0;
 
                info = (struct filesystem_vol_info *)(rsp->Buffer);
                info->VolumeCreationTime = 0;
+               serial_crc = crc32_le(serial_crc, share->name,
+                                     strlen(share->name));
+               serial_crc = crc32_le(serial_crc, share->path,
+                                     strlen(share->path));
+               serial_crc = crc32_le(serial_crc, ksmbd_netbios_name(),
+                                     strlen(ksmbd_netbios_name()));
                /* Taking dummy value of serial number*/
-               info->SerialNumber = cpu_to_le32(0xbc3ac512);
+               info->SerialNumber = cpu_to_le32(serial_crc);
                len = smbConvertToUTF16((__le16 *)info->VolumeLabel,
                                        share->name, PATH_MAX,
                                        conn->local_nls, 0);