Looks good to me.
Acked-by: Hyunchul Lee <hyc.lee@xxxxxxxxx>
2021년 10월 5일 (화) 오전 10:20, Namjae Jeon <linkinjeon@xxxxxxxxxx>님이 작성:
>
> Tom suggested to use buf_data_size that is already calculated, to verify
> these offsets.
>
> Cc: Tom Talpey <tom@xxxxxxxxxx>
> Cc: Ronnie Sahlberg <ronniesahlberg@xxxxxxxxx>
> Cc: Ralph Böhme <slow@xxxxxxxxx>
> Cc: Steve French <smfrench@xxxxxxxxx>
> Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
> Cc: Hyunchul Lee <hyc.lee@xxxxxxxxx>
> Suggested-by: Tom Talpey <tom@xxxxxxxxxx>
> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
> ---
> v2:
> - change data type of buf_data_size to signed to validate
> smb2_transfrom_hdr size.
> fs/ksmbd/smb2pdu.c | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> index b06361313889..bb030e4366ad 100644
> --- a/fs/ksmbd/smb2pdu.c
> +++ b/fs/ksmbd/smb2pdu.c
> @@ -8452,20 +8452,18 @@ int smb3_decrypt_req(struct ksmbd_work *work)
> struct smb2_hdr *hdr;
> unsigned int pdu_length = get_rfc1002_len(buf);
> struct kvec iov[2];
> - unsigned int buf_data_size = pdu_length + 4 -
> + int buf_data_size = pdu_length + 4 -
> sizeof(struct smb2_transform_hdr);
> struct smb2_transform_hdr *tr_hdr = (struct smb2_transform_hdr *)buf;
> int rc = 0;
>
> - if (pdu_length + 4 <
> - sizeof(struct smb2_transform_hdr) + sizeof(struct smb2_hdr)) {
> + if (buf_data_size < sizeof(struct smb2_hdr)) {
> pr_err("Transform message is too small (%u)\n",
> pdu_length);
> return -ECONNABORTED;
> }
>
> - if (pdu_length + 4 <
> - le32_to_cpu(tr_hdr->OriginalMessageSize) + sizeof(struct smb2_transform_hdr)) {
> + if (buf_data_size < le32_to_cpu(tr_hdr->OriginalMessageSize)) {
> pr_err("Transform message is broken\n");
> return -ECONNABORTED;
> }
> --
> 2.25.1
>
--
Thanks,
Hyunchul
