@@ -714,11 +714,13 @@ static void check_lifetime(struct work_struct *work)
rcu_read_lock();
hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
unsigned long age, tstamp;
+ u32 preferred_lft;
u32 valid_lft;
if (ifa->ifa_flags & IFA_F_PERMANENT)
continue;
+ preferred_lft = READ_ONCE(ifa->ifa_preferred_lft);
valid_lft = READ_ONCE(ifa->ifa_valid_lft);
tstamp = READ_ONCE(ifa->ifa_tstamp);
/* We try to batch several events at once. */
@@ -728,20 +730,18 @@ static void check_lifetime(struct work_struct *work)
if (valid_lft != INFINITY_LIFE_TIME &&
age >= valid_lft) {
change_needed = true;
- } else if (ifa->ifa_preferred_lft ==
+ } else if (preferred_lft ==
INFINITY_LIFE_TIME) {
continue;
- } else if (age >= ifa->ifa_preferred_lft) {
+ } else if (age >= preferred_lft) {
if (time_before(tstamp + valid_lft * HZ, next))
next = tstamp + valid_lft * HZ;
if (!(ifa->ifa_flags & IFA_F_DEPRECATED))
change_needed = true;
- } else if (time_before(tstamp +
- ifa->ifa_preferred_lft * HZ,
+ } else if (time_before(tstamp + preferred_lft * HZ,
next)) {
- next = tstamp +
- ifa->ifa_preferred_lft * HZ;
+ next = tstamp + preferred_lft * HZ;
}
}
rcu_read_unlock();
@@ -818,7 +818,7 @@ static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft,
if (addrconf_finite_timeout(timeout)) {
if (timeout == 0)
ifa->ifa_flags |= IFA_F_DEPRECATED;
- ifa->ifa_preferred_lft = timeout;
+ WRITE_ONCE(ifa->ifa_preferred_lft, timeout);
}
WRITE_ONCE(ifa->ifa_tstamp, jiffies);
if (!ifa->ifa_cstamp)
@@ -1698,7 +1698,7 @@ static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
tstamp = READ_ONCE(ifa->ifa_tstamp);
if (!(ifm->ifa_flags & IFA_F_PERMANENT)) {
- preferred = ifa->ifa_preferred_lft;
+ preferred = READ_ONCE(ifa->ifa_preferred_lft);
valid = READ_ONCE(ifa->ifa_valid_lft);
if (preferred != INFINITY_LIFE_TIME) {
long tval = (jiffies - tstamp) / HZ;
ifa->ifa_preferred_lft can be read locklessly. Add appropriate READ_ONCE()/WRITE_ONCE() annotations. Signed-off-by: Eric Dumazet <edumazet@google.com> --- net/ipv4/devinet.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)