[PATCH v3 74/88] scsi: qla2xxx: Clamp max_npiv_vports to VP_CTRL bitmap capacity

[Nilesh Javali <njavali@marvell.com>]

ha->max_npiv_vports is taken from firmware (mcp->mb[11]) and only
constrained so that (max_npiv_vports + 1) is a multiple of
MIN_MULTI_ID_FABRIC, which permits values of 63, 127, 191 and 255.
NPIV vports are then allocated up to that count.

VP enable uses the VP_CONFIG IOCB, which addresses a vport through a
plain vp_index byte, so a vp_index beyond 128 is enabled without issue.
VP disable, however, uses the VP_CTRL IOCB, which selects target vports
through the fixed 128-bit vp_idx_map bitmap. qla24xx_control_vp()
rejects a vp_index past that bitmap and the IOCB builder cannot set a bit
beyond 127, yet qla24xx_vport_delete() frees the local state regardless.
A vport with vp_index > 128 can therefore be created and enabled but
never disabled, leaving it permanently active in firmware: a resource
leak.

Cap ha->max_npiv_vports at init to the vp_idx_map capacity so such
vports are never created. This collapses 191/255 to 127 (still
modulo-valid) and leaves the real-world 63/127 cases unaffected.

Fixes: 4d0ea24769c8 ("[SCSI] qla2xxx: Retrieve max-NPIV support capabilities from FW.")
Cc: stable@vger.kernel.org
Reported-by: Sashiko <sashiko-dev@google.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
---
 drivers/scsi/qla2xxx/qla_fw.h   |  4 ++++
 drivers/scsi/qla2xxx/qla_init.c | 13 +++++++++++++
 drivers/scsi/qla2xxx/qla_mid.c  |  2 +-
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/qla2xxx/qla_fw.h b/drivers/scsi/qla2xxx/qla_fw.h
index b29abcc7f74f..98bc4a57b59b 100644
--- a/drivers/scsi/qla2xxx/qla_fw.h
+++ b/drivers/scsi/qla2xxx/qla_fw.h
@@ -1442,6 +1442,10 @@ struct vp_ctrl_entry_24xx {
 	uint8_t reserved_5[24];
 };
 
+/* vp_idx_map is a 128-bit (16-byte) bitmap selecting target VPs. */
+#define VP_CTRL_IDX_MAP_BITS \
+	(sizeof_field(struct vp_ctrl_entry_24xx, vp_idx_map) * 8)
+
 /*
  * Modify Virtual Port Configuration IOCB
  */
diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index d678e27213a9..1f20ab386003 100644
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -4412,6 +4412,19 @@ qla2x00_setup_chip(scsi_qla_host_t *vha)
 					    MIN_MULTI_ID_FABRIC))
 						ha->max_npiv_vports =
 						    MIN_MULTI_ID_FABRIC - 1;
+
+					/*
+					 * The VP_CTRL IOCB selects target VPs
+					 * through the fixed vp_idx_map bitmap,
+					 * so a vp_index beyond it can be enabled
+					 * via VP_CONFIG but never disabled via
+					 * VP_CTRL, leaking the VP.  Cap the count
+					 * to the bitmap capacity.
+					 */
+					if (ha->max_npiv_vports >=
+					    VP_CTRL_IDX_MAP_BITS)
+						ha->max_npiv_vports =
+						    VP_CTRL_IDX_MAP_BITS - 1;
 				}
 				qlt_config_nvram_with_fw_version(vha);
 				qla2x00_get_resource_cnts(vha);
diff --git a/drivers/scsi/qla2xxx/qla_mid.c b/drivers/scsi/qla2xxx/qla_mid.c
index 33bfc61d8165..4ad23d206add 100644
--- a/drivers/scsi/qla2xxx/qla_mid.c
+++ b/drivers/scsi/qla2xxx/qla_mid.c
@@ -996,7 +996,7 @@ int qla24xx_control_vp(scsi_qla_host_t *vha, int cmd)
 	 * (16-byte) vp_idx_map bitmap, so vp_index must fit within it even
 	 * if firmware advertises more NPIV vports.
 	 */
-	if (vp_index > sizeof_field(struct vp_ctrl_entry_24xx, vp_idx_map) * 8)
+	if (vp_index > VP_CTRL_IDX_MAP_BITS)
 		return QLA_PARAMETER_ERROR;
 
 	/* ref: INIT */
-- 
2.47.3