From e7135f484994494a38071e3653a83d21d305f50c Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 28 Feb 2024 13:54:28 +0000 Subject: ipv6: annotate data-races around cnf.mtu6 idev->cnf.mtu6 might be read locklessly, add appropriate READ_ONCE() and WRITE_ONCE() annotations. Signed-off-by: Eric Dumazet Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 4 ++-- net/ipv6/ndisc.c | 4 ++-- net/ipv6/route.c | 6 +++--- 3 files changed, 7 insertions(+), 7 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 6975685f55ea..1b534edc7ca2 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3671,7 +3671,7 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event, if (idev) { rt6_mtu_change(dev, dev->mtu); - idev->cnf.mtu6 = dev->mtu; + WRITE_ONCE(idev->cnf.mtu6, dev->mtu); break; } @@ -3763,7 +3763,7 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event, if (idev->cnf.mtu6 != dev->mtu && dev->mtu >= IPV6_MIN_MTU) { rt6_mtu_change(dev, dev->mtu); - idev->cnf.mtu6 = dev->mtu; + WRITE_ONCE(idev->cnf.mtu6, dev->mtu); } WRITE_ONCE(idev->tstamp, jiffies); inet6_ifinfo_notify(RTM_NEWLINK, idev); diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 8523f0595b01..e96d79cd34d2 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -1578,8 +1578,8 @@ skip_routeinfo: if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) { ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu); - } else if (in6_dev->cnf.mtu6 != mtu) { - in6_dev->cnf.mtu6 = mtu; + } else if (READ_ONCE(in6_dev->cnf.mtu6) != mtu) { + WRITE_ONCE(in6_dev->cnf.mtu6, mtu); fib6_metric_set(rt, RTAX_MTU, mtu); rt6_mtu_change(skb->dev, mtu); } diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 707d65bc9c0e..66c685b0b619 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1596,7 +1596,7 @@ static unsigned int fib6_mtu(const struct fib6_result *res) rcu_read_lock(); idev = __in6_dev_get(dev); - mtu = idev->cnf.mtu6; + mtu = READ_ONCE(idev->cnf.mtu6); rcu_read_unlock(); } @@ -3249,8 +3249,8 @@ u32 ip6_mtu_from_fib6(const struct fib6_result *res, mtu = IPV6_MIN_MTU; idev = __in6_dev_get(dev); - if (idev && idev->cnf.mtu6 > mtu) - mtu = idev->cnf.mtu6; + if (idev) + mtu = max_t(u32, mtu, READ_ONCE(idev->cnf.mtu6)); } mtu = min_t(unsigned int, mtu, IP6_MAX_MTU); -- cgit