Subject: [PATCH 28/36] bnxt_en: Protect bnxt_set_eee() and bnxt_set_pauseparam() with mutex.

From: Michael Chan <[email-masked]>
Date: Sun, 20 Sep 2020 21:08:56 -0400

[ Upstream commit a53906908148d64423398a62c4435efb0d09652c ]

All changes related to bp->link_info require the protection of the
link_lock mutex.  It's not sufficient to rely just on RTNL.

Fixes: 163e9ef63641 ("bnxt_en: Fix race when modifying pause settings.")
Reviewed-by: Edwin Peer <[email-masked]>
Signed-off-by: Michael Chan <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 31 ++++++++++++-------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index fd01bcc8e28d..1d15ff08f176 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -1665,9 +1665,12 @@ static int bnxt_set_pauseparam(struct net_device *dev,
 	if (!BNXT_SINGLE_PF(bp))
 		return -EOPNOTSUPP;
 
+	mutex_lock(&bp->link_lock);
 	if (epause->autoneg) {
-		if (!(link_info->autoneg & BNXT_AUTONEG_SPEED))
-			return -EINVAL;
+		if (!(link_info->autoneg & BNXT_AUTONEG_SPEED)) {
+			rc = -EINVAL;
+			goto pause_exit;
+		}
 
 		link_info->autoneg |= BNXT_AUTONEG_FLOW_CTRL;
 		if (bp->hwrm_spec_code >= 0x10201)
@@ -1688,11 +1691,11 @@ static int bnxt_set_pauseparam(struct net_device *dev,
 	if (epause->tx_pause)
 		link_info->req_flow_ctrl |= BNXT_LINK_PAUSE_TX;
 
-	if (netif_running(dev)) {
-		mutex_lock(&bp->link_lock);
+	if (netif_running(dev))
 		rc = bnxt_hwrm_set_pause(bp);
-		mutex_unlock(&bp->link_lock);
-	}
+
+pause_exit:
+	mutex_unlock(&bp->link_lock);
 	return rc;
 }
 
@@ -2397,8 +2400,7 @@ static int bnxt_set_eee(struct net_device *dev, struct ethtool_eee *edata)
 	struct bnxt *bp = netdev_priv(dev);
 	struct ethtool_eee *eee = &bp->eee;
 	struct bnxt_link_info *link_info = &bp->link_info;
-	u32 advertising =
-		 _bnxt_fw_to_ethtool_adv_spds(link_info->advertising, 0);
+	u32 advertising;
 	int rc = 0;
 
 	if (!BNXT_SINGLE_PF(bp))
@@ -2407,19 +2409,23 @@ static int bnxt_set_eee(struct net_device *dev, struct ethtool_eee *edata)
 	if (!(bp->flags & BNXT_FLAG_EEE_CAP))
 		return -EOPNOTSUPP;
 
+	mutex_lock(&bp->link_lock);
+	advertising = _bnxt_fw_to_ethtool_adv_spds(link_info->advertising, 0);
 	if (!edata->eee_enabled)
 		goto eee_ok;
 
 	if (!(link_info->autoneg & BNXT_AUTONEG_SPEED)) {
 		netdev_warn(dev, "EEE requires autoneg\n");
-		return -EINVAL;
+		rc = -EINVAL;
+		goto eee_exit;
 	}
 	if (edata->tx_lpi_enabled) {
 		if (bp->lpi_tmr_hi && (edata->tx_lpi_timer > bp->lpi_tmr_hi ||
 				       edata->tx_lpi_timer < bp->lpi_tmr_lo)) {
 			netdev_warn(dev, "Valid LPI timer range is %d and %d microsecs\n",
 				    bp->lpi_tmr_lo, bp->lpi_tmr_hi);
-			return -EINVAL;
+			rc = -EINVAL;
+			goto eee_exit;
 		} else if (!bp->lpi_tmr_hi) {
 			edata->tx_lpi_timer = eee->tx_lpi_timer;
 		}
@@ -2429,7 +2435,8 @@ static int bnxt_set_eee(struct net_device *dev, struct ethtool_eee *edata)
 	} else if (edata->advertised & ~advertising) {
 		netdev_warn(dev, "EEE advertised %x must be a subset of autoneg advertised speeds %x\n",
 			    edata->advertised, advertising);
-		return -EINVAL;
+		rc = -EINVAL;
+		goto eee_exit;
 	}
 
 	eee->advertised = edata->advertised;
@@ -2441,6 +2448,8 @@ static int bnxt_set_eee(struct net_device *dev, struct ethtool_eee *edata)
 	if (netif_running(dev))
 		rc = bnxt_hwrm_set_link_setting(bp, false, true);
 
+eee_exit:
+	mutex_unlock(&bp->link_lock);
 	return rc;
 }
 
-- 
2.26.2