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/pasemi/pasemi_mac.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/ethernet/pasemi/pasemi_mac.c') diff --git a/drivers/net/ethernet/pasemi/pasemi_mac.c b/drivers/net/ethernet/pasemi/pasemi_mac.c index ed7dd0a04235..62ba269da902 100644 --- a/drivers/net/ethernet/pasemi/pasemi_mac.c +++ b/drivers/net/ethernet/pasemi/pasemi_mac.c @@ -1639,7 +1639,7 @@ static int pasemi_mac_change_mtu(struct net_device *dev, int new_mtu) reg |= PAS_MAC_CFG_MACCFG_MAXF(new_mtu + ETH_HLEN + 4); write_mac_reg(mac, PAS_MAC_CFG_MACCFG, reg); - dev->mtu = new_mtu; + WRITE_ONCE(dev->mtu, new_mtu); /* MTU + ETH_HLEN + VLAN_HLEN + 2 64B cachelines */ mac->bufsz = new_mtu + ETH_HLEN + ETH_FCS_LEN + LOCAL_SKB_ALIGN + 128; -- cgit v1.2.3-70-g09d2