iscsi-target: Avoid OFMarker + IFMarker negotiation

This patch fixes a v4.2+ regression introduced by commit c04a6091
that removed support for obsolete sync-and-steering markers usage
as originally defined in RFC-3720.

The regression would involve attempting to send OFMarker=No +
IFMarker=No keys during opertional negotiation login phase,
including when initiators did not actually propose these keys.

The result for MSFT iSCSI initiators would be random junk in
TCP stream after the last successful login request was been sent
signaling the move to full feature phase (FFP) operation.

To address this bug, go ahead and avoid negotiating these keys
by default unless the initiator explicitly proposes them, but
still respond to them with 'No' if they are proposed.

Reported-by: Dragan Milivojević <galileo@pkm-inc.com>
Bisected-by: Christophe Vu-Brugier <cvubrugier@fastmail.fm>
Tested-by: Christophe Vu-Brugier <cvubrugier@fastmail.fm>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/target/iscsi/iscsi_target_parameters.c b/drivers/target/iscsi/iscsi_target_parameters.c
index e8a52f7d6204fc7c3e68fe5ad24f8e393ed0e16b..51d1734d5390409e2c98a34c4ad9fc787c1fc362 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_parameters.c
+++ b/drivers/target/iscsi/iscsi_target_parameters.c
@@ -407,6 +407,7 @@ int iscsi_create_default_params(struct iscsi_param_list **param_list_ptr)
                        TYPERANGE_UTF8, USE_INITIAL_ONLY);
        if (!param)
                goto out;
+
        /*
         * Extra parameters for ISER from RFC-5046
         */
@@ -496,9 +497,9 @@ int iscsi_set_keys_to_negotiate(
                } else if (!strcmp(param->name, SESSIONTYPE)) {
                        SET_PSTATE_NEGOTIATE(param);
                } else if (!strcmp(param->name, IFMARKER)) {
-                       SET_PSTATE_NEGOTIATE(param);
+                       SET_PSTATE_REJECT(param);
                } else if (!strcmp(param->name, OFMARKER)) {
-                       SET_PSTATE_NEGOTIATE(param);
+                       SET_PSTATE_REJECT(param);
                } else if (!strcmp(param->name, IFMARKINT)) {
                        SET_PSTATE_REJECT(param);
                } else if (!strcmp(param->name, OFMARKINT)) {