2021-10-11 21:14 GMT+09:00, Hyunchul Lee <hyc.lee@xxxxxxxxx>:
> Add buffer validation for smb direct.
>
> Signed-off-by: Hyunchul Lee <hyc.lee@xxxxxxxxx>
> ---
> fs/ksmbd/transport_rdma.c | 15 ++++++++++++++-
> 1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/fs/ksmbd/transport_rdma.c b/fs/ksmbd/transport_rdma.c
> index 3a7fa23ba850..18f50e06ad15 100644
> --- a/fs/ksmbd/transport_rdma.c
> +++ b/fs/ksmbd/transport_rdma.c
> @@ -549,6 +549,10 @@ static void recv_done(struct ib_cq *cq, struct ib_wc
> *wc)
>
> switch (recvmsg->type) {
> case SMB_DIRECT_MSG_NEGOTIATE_REQ:
> + if (wc->byte_len < sizeof(struct smb_direct_negotiate_req)) {
> + put_empty_recvmsg(t, recvmsg);
> + return;
> + }
> t->negotiation_requested = true;
> t->full_packet_received = true;
> wake_up_interruptible(&t->wait_status);
> @@ -556,9 +560,18 @@ static void recv_done(struct ib_cq *cq, struct ib_wc
> *wc)
> case SMB_DIRECT_MSG_DATA_TRANSFER: {
> struct smb_direct_data_transfer *data_transfer =
> (struct smb_direct_data_transfer *)recvmsg->packet;
> - int data_length = le32_to_cpu(data_transfer->data_length);
> + int data_length;
int data_length = le32_to_cpu(data_transfer->data_length);
> int avail_recvmsg_count, receive_credits;
>
> + if (wc->byte_len < offsetof(struct smb_direct_data_transfer, padding) ||
> + (le32_to_cpu(data_transfer->data_length) > 0 &&
> + wc->byte_len < sizeof(struct smb_direct_data_transfer) +
> + le32_to_cpu(data_transfer->data_length))) {
32bit overflow is possible here?
> + put_empty_recvmsg(t, recvmsg);
> + return;
> + }
> +
> + data_length = le32_to_cpu(data_transfer->data_length);
this can be moved to the above to avoid redundant le conversion.
Thanks!
> if (data_length) {
> if (t->full_packet_received)
> recvmsg->first_segment = true;
> --
> 2.25.1
>
>
