Commit 3ddc2231 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

inet: annotate data-races around ifa->ifa_flags 



ifa->ifa_flags can be read locklessly.

Add appropriate READ_ONCE()/WRITE_ONCE() annotations.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9f6fa3c4

net/ipv4/devinet.c

+13 −9
Original line number Diff line number Diff line
@@ -716,8 +716,10 @@ static void check_lifetime(struct work_struct *work) 
			unsigned long age, tstamp;

			u32 preferred_lft;

			u32 valid_lft;

			u32 flags;



			if (ifa->ifa_flags & IFA_F_PERMANENT)

			flags = READ_ONCE(ifa->ifa_flags);

			if (flags & IFA_F_PERMANENT)

				continue;



			preferred_lft = READ_ONCE(ifa->ifa_preferred_lft);
@@ -737,7 +739,7 @@ static void check_lifetime(struct work_struct *work) 
				if (time_before(tstamp + valid_lft * HZ, next))

					next = tstamp + valid_lft * HZ;



				if (!(ifa->ifa_flags & IFA_F_DEPRECATED))

				if (!(flags & IFA_F_DEPRECATED))

					change_needed = true;

			} else if (time_before(tstamp + preferred_lft * HZ,

					       next)) {
@@ -805,21 +807,23 @@ static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft, 
			     __u32 prefered_lft)

{

	unsigned long timeout;

	u32 flags;



	ifa->ifa_flags &= ~(IFA_F_PERMANENT | IFA_F_DEPRECATED);

	flags = ifa->ifa_flags & ~(IFA_F_PERMANENT | IFA_F_DEPRECATED);



	timeout = addrconf_timeout_fixup(valid_lft, HZ);

	if (addrconf_finite_timeout(timeout))

		WRITE_ONCE(ifa->ifa_valid_lft, timeout);

	else

		ifa->ifa_flags |= IFA_F_PERMANENT;

		flags |= IFA_F_PERMANENT;



	timeout = addrconf_timeout_fixup(prefered_lft, HZ);

	if (addrconf_finite_timeout(timeout)) {

		if (timeout == 0)

			ifa->ifa_flags |= IFA_F_DEPRECATED;

			flags |= IFA_F_DEPRECATED;

		WRITE_ONCE(ifa->ifa_preferred_lft, timeout);

	}

	WRITE_ONCE(ifa->ifa_flags, flags);

	WRITE_ONCE(ifa->ifa_tstamp, jiffies);

	if (!ifa->ifa_cstamp)

		WRITE_ONCE(ifa->ifa_cstamp, ifa->ifa_tstamp);
@@ -1313,7 +1317,7 @@ static __be32 in_dev_select_addr(const struct in_device *in_dev, 
	const struct in_ifaddr *ifa;



	in_dev_for_each_ifa_rcu(ifa, in_dev) {

		if (ifa->ifa_flags & IFA_F_SECONDARY)

		if (READ_ONCE(ifa->ifa_flags) & IFA_F_SECONDARY)

			continue;

		if (ifa->ifa_scope != RT_SCOPE_LINK &&

		    ifa->ifa_scope <= scope)
@@ -1341,7 +1345,7 @@ __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope) 
		localnet_scope = RT_SCOPE_LINK;



	in_dev_for_each_ifa_rcu(ifa, in_dev) {

		if (ifa->ifa_flags & IFA_F_SECONDARY)

		if (READ_ONCE(ifa->ifa_flags) & IFA_F_SECONDARY)

			continue;

		if (min(ifa->ifa_scope, localnet_scope) > scope)

			continue;
@@ -1688,7 +1692,7 @@ static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa, 
	ifm = nlmsg_data(nlh);

	ifm->ifa_family = AF_INET;

	ifm->ifa_prefixlen = ifa->ifa_prefixlen;

	ifm->ifa_flags = ifa->ifa_flags;

	ifm->ifa_flags = READ_ONCE(ifa->ifa_flags);

	ifm->ifa_scope = ifa->ifa_scope;

	ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
@@ -1728,7 +1732,7 @@ static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa, 
	     nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) ||

	    (ifa->ifa_proto &&

	     nla_put_u8(skb, IFA_PROTO, ifa->ifa_proto)) ||

	    nla_put_u32(skb, IFA_FLAGS, ifa->ifa_flags) ||

	    nla_put_u32(skb, IFA_FLAGS, ifm->ifa_flags) ||

	    (ifa->ifa_rt_priority &&

	     nla_put_u32(skb, IFA_RT_PRIORITY, ifa->ifa_rt_priority)) ||

	    put_cacheinfo(skb, READ_ONCE(ifa->ifa_cstamp), tstamp,