From 1eb2cded45b35816085c1f962933c187d970f9dc Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 6 May 2024 10:28:12 +0000 Subject: net: annotate writes on dev->mtu from ndo_change_mtu() Simon reported that ndo_change_mtu() methods were never updated to use WRITE_ONCE(dev->mtu, new_mtu) as hinted in commit 501a90c94510 ("inet: protect against too small mtu values.") We read dev->mtu without holding RTNL in many places, with READ_ONCE() annotations. It is time to take care of ndo_change_mtu() methods to use corresponding WRITE_ONCE() Signed-off-by: Eric Dumazet Reported-by: Simon Horman Closes: https://lore.kernel.org/netdev/20240505144608.GB67882@kernel.org/ Reviewed-by: Jacob Keller Reviewed-by: Sabrina Dubroca Reviewed-by: Simon Horman Acked-by: Shannon Nelson Link: https://lore.kernel.org/r/20240506102812.3025432-1-edumazet@google.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/atheros/ag71xx.c | 2 +- drivers/net/ethernet/atheros/alx/main.c | 2 +- drivers/net/ethernet/atheros/atl1c/atl1c_main.c | 2 +- drivers/net/ethernet/atheros/atl1e/atl1e_main.c | 2 +- drivers/net/ethernet/atheros/atlx/atl1.c | 2 +- drivers/net/ethernet/atheros/atlx/atl2.c | 2 +- 6 files changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/net/ethernet/atheros') diff --git a/drivers/net/ethernet/atheros/ag71xx.c b/drivers/net/ethernet/atheros/ag71xx.c index 0f2f400b5bc4..a38be924cdaa 100644 --- a/drivers/net/ethernet/atheros/ag71xx.c +++ b/drivers/net/ethernet/atheros/ag71xx.c @@ -1788,7 +1788,7 @@ static int ag71xx_change_mtu(struct net_device *ndev, int new_mtu) { struct ag71xx *ag = netdev_priv(ndev); - ndev->mtu = new_mtu; + WRITE_ONCE(ndev->mtu, new_mtu); ag71xx_wr(ag, AG71XX_REG_MAC_MFL, ag71xx_max_frame_len(ndev->mtu)); diff --git a/drivers/net/ethernet/atheros/alx/main.c b/drivers/net/ethernet/atheros/alx/main.c index 49bb9a8f00e6..3d28654e5df7 100644 --- a/drivers/net/ethernet/atheros/alx/main.c +++ b/drivers/net/ethernet/atheros/alx/main.c @@ -1176,7 +1176,7 @@ static int alx_change_mtu(struct net_device *netdev, int mtu) struct alx_priv *alx = netdev_priv(netdev); int max_frame = ALX_MAX_FRAME_LEN(mtu); - netdev->mtu = mtu; + WRITE_ONCE(netdev->mtu, mtu); alx->hw.mtu = mtu; alx->rxbuf_size = max(max_frame, ALX_DEF_RXBUF_SIZE); netdev_update_features(netdev); diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c index 46cdc32b4e31..c571614b1d50 100644 --- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c +++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c @@ -561,7 +561,7 @@ static int atl1c_change_mtu(struct net_device *netdev, int new_mtu) if (netif_running(netdev)) { while (test_and_set_bit(__AT_RESETTING, &adapter->flags)) msleep(1); - netdev->mtu = new_mtu; + WRITE_ONCE(netdev->mtu, new_mtu); adapter->hw.max_frame_size = new_mtu; atl1c_set_rxbufsize(adapter, netdev); atl1c_down(adapter); diff --git a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c index 5f2a6fcba967..9b778b34b67e 100644 --- a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c +++ b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c @@ -428,7 +428,7 @@ static int atl1e_change_mtu(struct net_device *netdev, int new_mtu) if (netif_running(netdev)) { while (test_and_set_bit(__AT_RESETTING, &adapter->flags)) msleep(1); - netdev->mtu = new_mtu; + WRITE_ONCE(netdev->mtu, new_mtu); adapter->hw.max_frame_size = new_mtu; adapter->hw.rx_jumbo_th = (max_frame + 7) >> 3; atl1e_down(adapter); diff --git a/drivers/net/ethernet/atheros/atlx/atl1.c b/drivers/net/ethernet/atheros/atlx/atl1.c index a9014d7932db..3afd3627ce48 100644 --- a/drivers/net/ethernet/atheros/atlx/atl1.c +++ b/drivers/net/ethernet/atheros/atlx/atl1.c @@ -2687,7 +2687,7 @@ static int atl1_change_mtu(struct net_device *netdev, int new_mtu) adapter->rx_buffer_len = (max_frame + 7) & ~7; adapter->hw.rx_jumbo_th = adapter->rx_buffer_len / 8; - netdev->mtu = new_mtu; + WRITE_ONCE(netdev->mtu, new_mtu); if (netif_running(netdev)) { atl1_down(adapter); atl1_up(adapter); diff --git a/drivers/net/ethernet/atheros/atlx/atl2.c b/drivers/net/ethernet/atheros/atlx/atl2.c index bcfc9488125b..fa9a4919f25d 100644 --- a/drivers/net/ethernet/atheros/atlx/atl2.c +++ b/drivers/net/ethernet/atheros/atlx/atl2.c @@ -905,7 +905,7 @@ static int atl2_change_mtu(struct net_device *netdev, int new_mtu) struct atl2_hw *hw = &adapter->hw; /* set MTU */ - netdev->mtu = new_mtu; + WRITE_ONCE(netdev->mtu, new_mtu); hw->max_frame_size = new_mtu; ATL2_WRITE_REG(hw, REG_MTU, new_mtu + ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN); -- cgit v1.2.3