diff mbox series

ksmbd: add buffer validation for smb direct

Message ID 20211011121404.26392-1-hyc.lee@gmail.com
State New
Headers show
Series ksmbd: add buffer validation for smb direct | expand

Commit Message

Hyunchul Lee Oct. 11, 2021, 12:14 p.m. UTC
Add buffer validation for smb direct.

Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
---
 fs/ksmbd/transport_rdma.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

Comments

Namjae Jeon Oct. 12, 2021, 8:01 a.m. UTC | #1
2021-10-11 21:14 GMT+09:00, Hyunchul Lee <hyc.lee@gmail.com>:
> Add buffer validation for smb direct.
>
> Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
> ---
>  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
>
>
Hyunchul Lee Oct. 12, 2021, 11:10 p.m. UTC | #2
2021년 10월 12일 (화) 오후 5:01, Namjae Jeon <linkinjeon@kernel.org>님이 작성:
>
> 2021-10-11 21:14 GMT+09:00, Hyunchul Lee <hyc.lee@gmail.com>:
> > Add buffer validation for smb direct.
> >
> > Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
> > ---
> >  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?

Yes, type casting is needed.

>
> > +                     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.

Okay, I will move this.
Thank you for your comments.

>
> Thanks!
> >               if (data_length) {
> >                       if (t->full_packet_received)
> >                               recvmsg->first_segment = true;
> > --
> > 2.25.1
> >
> >
diff mbox series

Patch

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 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))) {
+			put_empty_recvmsg(t, recvmsg);
+			return;
+		}
+
+		data_length = le32_to_cpu(data_transfer->data_length);
 		if (data_length) {
 			if (t->full_packet_received)
 				recvmsg->first_segment = true;