From ad57c140b86de638bc841a913fbbd87b4204abf2 Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Thu, 4 Jun 2015 19:49:21 +0300 Subject: [PATCH] iser-target: Fix possible use-after-free commit 524630d5824c7a75aab568c6bd1423fd748cd3bb upstream. iser connection termination process happens in 2 stages: - isert_wait_conn: - resumes rdma disconnect - wait for session commands - wait for flush completions (post a marked wr to signal we are done) - wait for logout completion - queue work for connection cleanup (depends on disconnected/timewait events) - isert_free_conn - last reference put on the connection In case we are terminating during IOs, we might be posting send/recv requests after we posted the last work request which might lead to a use-after-free condition in isert_handle_wc. After we posted the last wr in isert_wait_conn we are guaranteed that no successful completions will follow (meaning no new work request posts may happen) but other flush errors might still come. So before we put the last reference on the connection, we repeat the process of posting a marked work request (isert_wait4flush) in order to make sure all pending completions were flushed. Signed-off-by: Sagi Grimberg Signed-off-by: Jenny Falkovich Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/ulp/isert/ib_isert.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c index 1b1644113e690..ac72ece701605 100644 --- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -3313,6 +3313,7 @@ static void isert_free_conn(struct iscsi_conn *conn) { struct isert_conn *isert_conn = conn->context; + isert_wait4flush(isert_conn); isert_put_conn(isert_conn); } -- 2.47.2