[PATCH net 6/6] bnxt_en: Fix possible corruption in DCB parameters from firmware.

[Michael Chan]

From: Sankar Patchineelam <sankar.patchinee...@broadcom.com>

hwrm_send_message() is replaced with _hwrm_send_message(), and
hwrm_cmd_lock mutex lock is grabbed for the whole period of
firmware call until the firmware DCB parameters have been copied.
This will prevent possible corruption of the firmware data.

Fixes: 7df4ae9fe855 ("bnxt_en: Implement DCBNL to support host-based DCBX.")
Signed-off-by: Sankar Patchineelam <sankar.patchinee...@broadcom.com>
Signed-off-by: Michael Chan <michael.c...@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c 
b/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c
index aa1f3a2..fed37cd 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c
@@ -50,7 +50,9 @@ static int bnxt_hwrm_queue_pri2cos_qcfg(struct bnxt *bp, 
struct ieee_ets *ets)
 
        bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_QUEUE_PRI2COS_QCFG, -1, -1);
        req.flags = cpu_to_le32(QUEUE_PRI2COS_QCFG_REQ_FLAGS_IVLAN);
-       rc = hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
+
+       mutex_lock(&bp->hwrm_cmd_lock);
+       rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
        if (!rc) {
                u8 *pri2cos = &resp->pri0_cos_queue_id;
                int i, j;
@@ -66,6 +68,7 @@ static int bnxt_hwrm_queue_pri2cos_qcfg(struct bnxt *bp, 
struct ieee_ets *ets)
                        }
                }
        }
+       mutex_unlock(&bp->hwrm_cmd_lock);
        return rc;
 }
 
@@ -119,9 +122,13 @@ static int bnxt_hwrm_queue_cos2bw_qcfg(struct bnxt *bp, 
struct ieee_ets *ets)
        int rc, i;
 
        bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_QUEUE_COS2BW_QCFG, -1, -1);
-       rc = hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
-       if (rc)
+
+       mutex_lock(&bp->hwrm_cmd_lock);
+       rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
+       if (rc) {
+               mutex_unlock(&bp->hwrm_cmd_lock);
                return rc;
+       }
 
        data = &resp->queue_id0 + offsetof(struct bnxt_cos2bw_cfg, queue_id);
        for (i = 0; i < bp->max_tc; i++, data += sizeof(cos2bw) - 4) {
@@ -143,6 +150,7 @@ static int bnxt_hwrm_queue_cos2bw_qcfg(struct bnxt *bp, 
struct ieee_ets *ets)
                        }
                }
        }
+       mutex_unlock(&bp->hwrm_cmd_lock);
        return 0;
 }
 
@@ -240,12 +248,17 @@ static int bnxt_hwrm_queue_pfc_qcfg(struct bnxt *bp, 
struct ieee_pfc *pfc)
        int rc;
 
        bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_QUEUE_PFCENABLE_QCFG, -1, -1);
-       rc = hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
-       if (rc)
+
+       mutex_lock(&bp->hwrm_cmd_lock);
+       rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
+       if (rc) {
+               mutex_unlock(&bp->hwrm_cmd_lock);
                return rc;
+       }
 
        pri_mask = le32_to_cpu(resp->flags);
        pfc->pfc_en = pri_mask;
+       mutex_unlock(&bp->hwrm_cmd_lock);
        return 0;
 }
 
-- 
1.8.3.1