We can end up freeing a command too early during conn cleanup by doing:
1. Send iserts N 1MB writes.
2. Pull cable or down the port isert is using.
3. isert_wait_conn's call to isert_put_unsol_pending_cmds races
with a running isert_send_done -> isert_completion_put -> isert_put_cmd
where isert_put_unsol_pending_cmds sees the cmd on the conn_cmd_list
and it does a isert_put_cmd which will free the cmd. Then isert_send_done
is run and will access the freed command while doing it's normal command
completion:
isert_completion_put -> isert_put_cmd -> transport_generic_free_cmd
This patch has us increment write_data_done, so
isert_put_unsol_pending_cmds can correctly detect commands which will we
will not be calling isert_send_done for.
Fixes: 38a2d0d429f1 ("IB/isert: convert to the generic RDMA READ/WRITE API")
[code written and suggested by]
Suggested-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
Reviewed-by: Maurizio Lombardi <mlombard@xxxxxxxxxx>
---
drivers/infiniband/ulp/isert/ib_isert.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index 516fa37494e1..a44da60352f6 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -1636,7 +1636,7 @@ isert_rdma_read_done(struct ib_cq *cq, struct ib_wc *wc)
if (isert_prot_cmd(isert_conn, se_cmd))
ret = isert_check_pi_status(se_cmd, isert_cmd->rw.reg->mr);
isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
- cmd->write_data_done = 0;
+ cmd->write_data_done = se_cmd->data_length; /* done fetching data */
isert_dbg("Cmd: %p RDMA_READ comp calling execute_cmd\n", isert_cmd);
spin_lock_bh(&cmd->istate_lock);
--
2.31.1
