target: Return error to initiator if SET TARGET PORT GROUPS emulation fails

The error paths in target_emulate_set_target_port_groups() are all
essentially "rc = -EINVAL; goto out;" but the code at "out:" ignores
rc and always returns success.  This means that even if eg explicit
ALUA is turned off, the initiator will always see a good SCSI status
for SET TARGET PORT GROUPS.

Fix this by returning rc as is intended.  It appears this bug was
added by the following patch:

commit 05d1c7c0d0db4cc25548d9aadebb416888a82327
Author: Andy Grover <agrover@redhat.com>
Date:   Wed Jul 20 19:13:28 2011 +0000

    target: Make all control CDBs scatter-gather

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c
index e624b83..9179997 100644 (file)
--- a/drivers/target/target_core_alua.c
+++ b/drivers/target/target_core_alua.c
@@ -374,8 +374,9 @@ int target_emulate_set_target_port_groups(struct se_cmd *cmd)
 
 out:
        transport_kunmap_data_sg(cmd);
-       target_complete_cmd(cmd, GOOD);
-       return 0;
+       if (!rc)
+               target_complete_cmd(cmd, GOOD);
+       return rc;
 }
 
 static inline int core_alua_state_nonoptimized(