ksmbd: smbd: fix missing client's memory region invalidation

if the Channel of a SMB2 WRITE request is
SMB2_CHANNEL_RDMA_V1_INVALIDTE, a client
does not invalidate its memory regions but
ksmbd must do it by sending a SMB2 WRITE response
with IB_WR_SEND_WITH_INV.

But if errors occur while processing a SMB2
READ/WRITE request, ksmbd sends a response
with IB_WR_SEND. So a client could use memory
regions already in use.

Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 867ed98..15f331d 100644 (file)
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -6124,25 +6124,33 @@ out:
        return err;
 }
 
-static ssize_t smb2_read_rdma_channel(struct ksmbd_work *work,
-                                     struct smb2_read_req *req, void *data_buf,
-                                     size_t length)
+static int smb2_set_remote_key_for_rdma(struct ksmbd_work *work,
+                                       struct smb2_buffer_desc_v1 *desc,
+                                       __le32 Channel,
+                                       __le16 ChannelInfoOffset,
+                                       __le16 ChannelInfoLength)
 {
-       struct smb2_buffer_desc_v1 *desc =
-               (struct smb2_buffer_desc_v1 *)&req->Buffer[0];
-       int err;
-
        if (work->conn->dialect == SMB30_PROT_ID &&
-           req->Channel != SMB2_CHANNEL_RDMA_V1)
+           Channel != SMB2_CHANNEL_RDMA_V1)
                return -EINVAL;
 
-       if (req->ReadChannelInfoOffset == 0 ||
-           le16_to_cpu(req->ReadChannelInfoLength) < sizeof(*desc))
+       if (ChannelInfoOffset == 0 ||
+           le16_to_cpu(ChannelInfoLength) < sizeof(*desc))
                return -EINVAL;
 
        work->need_invalidate_rkey =
-               (req->Channel == SMB2_CHANNEL_RDMA_V1_INVALIDATE);
+               (Channel == SMB2_CHANNEL_RDMA_V1_INVALIDATE);
        work->remote_key = le32_to_cpu(desc->token);
+       return 0;
+}
+
+static ssize_t smb2_read_rdma_channel(struct ksmbd_work *work,
+                                     struct smb2_read_req *req, void *data_buf,
+                                     size_t length)
+{
+       struct smb2_buffer_desc_v1 *desc =
+               (struct smb2_buffer_desc_v1 *)&req->Buffer[0];
+       int err;
 
        err = ksmbd_conn_rdma_write(work->conn, data_buf, length,
                                    le32_to_cpu(desc->token),
@@ -6165,7 +6173,7 @@ int smb2_read(struct ksmbd_work *work)
        struct ksmbd_conn *conn = work->conn;
        struct smb2_read_req *req;
        struct smb2_read_rsp *rsp;
-       struct ksmbd_file *fp;
+       struct ksmbd_file *fp = NULL;
        loff_t offset;
        size_t length, mincount;
        ssize_t nbytes = 0, remain_bytes = 0;
@@ -6179,6 +6187,18 @@ int smb2_read(struct ksmbd_work *work)
                return smb2_read_pipe(work);
        }
 
+       if (req->Channel == SMB2_CHANNEL_RDMA_V1_INVALIDATE ||
+           req->Channel == SMB2_CHANNEL_RDMA_V1) {
+               err = smb2_set_remote_key_for_rdma(work,
+                                                  (struct smb2_buffer_desc_v1 *)
+                                                  &req->Buffer[0],
+                                                  req->Channel,
+                                                  req->ReadChannelInfoOffset,
+                                                  req->ReadChannelInfoLength);
+               if (err)
+                       goto out;
+       }
+
        fp = ksmbd_lookup_fd_slow(work, le64_to_cpu(req->VolatileFileId),
                                  le64_to_cpu(req->PersistentFileId));
        if (!fp) {
@@ -6364,21 +6384,6 @@ static ssize_t smb2_write_rdma_channel(struct ksmbd_work *work,
 
        desc = (struct smb2_buffer_desc_v1 *)&req->Buffer[0];
 
-       if (work->conn->dialect == SMB30_PROT_ID &&
-           req->Channel != SMB2_CHANNEL_RDMA_V1)
-               return -EINVAL;
-
-       if (req->Length != 0 || req->DataOffset != 0)
-               return -EINVAL;
-
-       if (req->WriteChannelInfoOffset == 0 ||
-           le16_to_cpu(req->WriteChannelInfoLength) < sizeof(*desc))
-               return -EINVAL;
-
-       work->need_invalidate_rkey =
-               (req->Channel == SMB2_CHANNEL_RDMA_V1_INVALIDATE);
-       work->remote_key = le32_to_cpu(desc->token);
-
        data_buf = kvmalloc(length, GFP_KERNEL | __GFP_ZERO);
        if (!data_buf)
                return -ENOMEM;
@@ -6425,6 +6430,20 @@ int smb2_write(struct ksmbd_work *work)
                return smb2_write_pipe(work);
        }
 
+       if (req->Channel == SMB2_CHANNEL_RDMA_V1 ||
+           req->Channel == SMB2_CHANNEL_RDMA_V1_INVALIDATE) {
+               if (req->Length != 0 || req->DataOffset != 0)
+                       return -EINVAL;
+               err = smb2_set_remote_key_for_rdma(work,
+                                                  (struct smb2_buffer_desc_v1 *)
+                                                  &req->Buffer[0],
+                                                  req->Channel,
+                                                  req->WriteChannelInfoOffset,
+                                                  req->WriteChannelInfoLength);
+               if (err)
+                       goto out;
+       }
+
        if (!test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE)) {
                ksmbd_debug(SMB, "User does not have write permission\n");
                err = -EACCES;