[PATCH 11/18] IB/isert: Fix use after free during conn cleanup

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


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
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);

[Index of Archives]     [Linux SCSI]     [Kernel Newbies]     [Linux SCSI Target Infrastructure]     [Share Photos]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Linux IIO]     [Device Mapper]

  Powered by Linux