[PATCH 5.15 173/917] ksmbd: set unique value to volume serial field in FS_VOLUME_INFORMATION

[Greg Kroah-Hartman]

From: Namjae Jeon <linkinjeon@xxxxxxxxxx>

commit 5d2f0b1083eb158bdff01dd557e2c25046c0a7d2 upstream.

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@xxxxxxxxxxxxxxx # v5.15
Reported-by: Steve French <smfrench@xxxxxxxxx>
Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 fs/ksmbd/Kconfig   |    1 +
 fs/ksmbd/server.c  |    1 +
 fs/ksmbd/smb2pdu.c |    9 ++++++++-
 3 files changed, 10 insertions(+), 1 deletion(-)

--- 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
--- 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)
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -4891,11 +4891,18 @@ static int smb2_get_info_filesystem(stru
 	{
 		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);