[PATCH] qed: iscsi: limit command queue array fill to the ramrod array size

[Pengpeng Hou]

qed_sp_iscsi_func_start() validates p_params->num_queues against the
number of command queues exposed by the hardware resource table, but it
then uses that count to fill q_params.cq_cmdq_sb_num_arr[] in the SCSI
init ramrod. That array is fixed at SCSI_MAX_NUM_OF_CMDQS entries.

The in-tree qedi caller derives num_queues from the device's reported
num_cqs and the online CPU count, so current-tree callers can request
more queues than fit in the fixed ramrod array on sufficiently large
systems even though the existing hardware-resource check passes.

Reject queue counts that exceed the command queue array capacity before
filling the ramrod.

Signed-off-by: Pengpeng Hou <pengpeng@xxxxxxxxxxx>
---
 drivers/net/ethernet/qlogic/qed/qed_iscsi.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/net/ethernet/qlogic/qed/qed_iscsi.c b/drivers/net/ethernet/qlogic/qed/qed_iscsi.c
index e16808291338..62cf85f9a042 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_iscsi.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_iscsi.c
@@ -177,6 +177,15 @@ qed_sp_iscsi_func_start(struct qed_hwfn *p_hwfn,
 		return -EINVAL;
 	}
 
+	if (p_params->num_queues > ARRAY_SIZE(p_queue->cq_cmdq_sb_num_arr)) {
+		DP_ERR(p_hwfn,
+		       "Cannot fit %u queues in %zu command queue slots. Aborting function start\n",
+		       p_params->num_queues,
+		       ARRAY_SIZE(p_queue->cq_cmdq_sb_num_arr));
+		qed_sp_destroy_request(p_hwfn, p_ent);
+		return -EINVAL;
+	}
+
 	val = p_params->half_way_close_timeout;
 	p_init->half_way_close_timeout = cpu_to_le16(val);
 	p_init->num_sq_pages_in_ring = p_params->num_sq_pages_in_ring;
-- 
2.50.1 (Apple Git-155)