[SCSI] iscsi_tcp: fix partial digest recv

When a digest is spread across two network buffers, we currently
ignore this and try to check the digest with the partial buffer.
Or course this fails. This patch has use iscsi_tcp_copy to
copy the whole digest before testing it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 5d292d0b65ec1cec4302806f003a0cfe43490f31..d91e8949c71e40ea12b6f7e406f0a4bbef381861 100644 (file)
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -648,10 +648,9 @@ iscsi_ctask_copy(struct iscsi_tcp_conn *tcp_conn, struct iscsi_cmd_task *ctask,
  *     byte counters.
  **/
 static inline int
-iscsi_tcp_copy(struct iscsi_conn *conn)
+iscsi_tcp_copy(struct iscsi_conn *conn, int buf_size)
 {
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       int buf_size = tcp_conn->in.datalen;
        int buf_left = buf_size - tcp_conn->data_copied;
        int size = min(tcp_conn->in.copy, buf_left);
        int rc;
@@ -812,7 +811,7 @@ iscsi_data_recv(struct iscsi_conn *conn)
                 * Collect data segment to the connection's data
                 * placeholder
                 */
-               if (iscsi_tcp_copy(conn)) {
+               if (iscsi_tcp_copy(conn, tcp_conn->in.datalen)) {
                        rc = -EAGAIN;
                        goto exit;
                }
@@ -899,10 +898,15 @@ more:
 
                debug_tcp("extra data_recv offset %d copy %d\n",
                          tcp_conn->in.offset, tcp_conn->in.copy);
-               skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
-                               &recv_digest, 4);
-               tcp_conn->in.offset += 4;
-               tcp_conn->in.copy -= 4;
+               rc = iscsi_tcp_copy(conn, sizeof(uint32_t));
+               if (rc) {
+                       if (rc == -EAGAIN)
+                               goto again;
+                       iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+                       return 0;
+               }
+
+               memcpy(&recv_digest, conn->data, sizeof(uint32_t));
                if (recv_digest != tcp_conn->in.datadgst) {
                        debug_tcp("iscsi_tcp: data digest error!"
                                  "0x%x != 0x%x\n", recv_digest,
@@ -942,9 +946,10 @@ more:
                                                     &sg, 1);
                        }
                        crypto_digest_final(tcp_conn->rx_tfm,
-                                           (u8 *) & tcp_conn->in.datadgst);
+                                           (u8 *) &tcp_conn->in.datadgst);
                        debug_tcp("rx digest 0x%x\n", tcp_conn->in.datadgst);
                        tcp_conn->in_progress = IN_PROGRESS_DDIGEST_RECV;
+                       tcp_conn->data_copied = 0;
                } else
                        tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
        }