CIFS: Fix credit calculation for encrypted reads with errors

We do need to account for credits received in error responses
to read requests on encrypted sessions.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

1 files changed, 14 insertions, 10 deletions

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index fa8d2e1076c8..73f9c6af4065 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -3207,11 +3207,23 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
                         server->ops->is_status_pending(buf, server, 0))
                 return -1;
 
-        rdata->result = server->ops->map_error(buf, false);
+        /* set up first two iov to get credits */
+        rdata->iov[0].iov_base = buf;
+        rdata->iov[0].iov_len = 4;
+        rdata->iov[1].iov_base = buf + 4;
+        rdata->iov[1].iov_len =
+                min_t(unsigned int, buf_len, server->vals->read_rsp_size) - 4;
+        cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
+                 rdata->iov[0].iov_base, rdata->iov[0].iov_len);
+        cifs_dbg(FYI, "1: iov_base=%p iov_len=%zu\n",
+                 rdata->iov[1].iov_base, rdata->iov[1].iov_len);
+
+        rdata->result = server->ops->map_error(buf, true);
         if (rdata->result != 0) {
                 cifs_dbg(FYI, "%s: server returned error %d\n",
                          __func__, rdata->result);
-                dequeue_mid(mid, rdata->result);
+                /* normal error on read response */
+                dequeue_mid(mid, false);
                 return 0;
         }
 
@@ -3284,14 +3296,6 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
                 return 0;
         }
 
-        /* set up first iov for signature check */
-        rdata->iov[0].iov_base = buf;
-        rdata->iov[0].iov_len = 4;
-        rdata->iov[1].iov_base = buf + 4;
-        rdata->iov[1].iov_len = server->vals->read_rsp_size - 4;
-        cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
-                 rdata->iov[0].iov_base, server->vals->read_rsp_size);
-
         length = rdata->copy_into_pages(server, rdata, &iter);
 
         kfree(bvec);