From 9a63b999ae5435d82a5c353c6b1467100f857742 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Mon, 11 Oct 2021 12:48:31 +0900 Subject: [PATCH] ksmbd: fix potencial 32bit overflow from data area check in smb2_write DataOffset and Length validation can be potencial 32bit overflow. This patch fix it. Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/ksmbd/smb2pdu.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index 79b296abe04e..7b4689f2df49 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -6197,8 +6197,7 @@ static noinline int smb2_write_pipe(struct ksmbd_work *work) (offsetof(struct smb2_write_req, Buffer) - 4)) { data_buf = (char *)&req->Buffer[0]; } else { - if ((le16_to_cpu(req->DataOffset) > get_rfc1002_len(req)) || - (le16_to_cpu(req->DataOffset) + length > get_rfc1002_len(req))) { + if ((u64)le16_to_cpu(req->DataOffset) + length > get_rfc1002_len(req)) { pr_err("invalid write data offset %u, smb_len %u\n", le16_to_cpu(req->DataOffset), get_rfc1002_len(req)); @@ -6356,8 +6355,7 @@ int smb2_write(struct ksmbd_work *work) (offsetof(struct smb2_write_req, Buffer) - 4)) { data_buf = (char *)&req->Buffer[0]; } else { - if ((le16_to_cpu(req->DataOffset) > get_rfc1002_len(req)) || - (le16_to_cpu(req->DataOffset) + length > get_rfc1002_len(req))) { + if ((u64)le16_to_cpu(req->DataOffset) + length > get_rfc1002_len(req)) { pr_err("invalid write data offset %u, smb_len %u\n", le16_to_cpu(req->DataOffset), get_rfc1002_len(req));