Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c988d1e8 authored by Jiri Pirko's avatar Jiri Pirko Committed by David S. Miller
Browse files

net: ipv4: fix schedule while atomic bug in check_lifetime() 



move might_sleep operations out of the rcu_read_lock() section.
Also fix iterating over ifa_dev->ifa_list

Introduced by: commit 5c766d64 "ipv4: introduce address lifetime"

Signed-off-by: default avatarJiri Pirko <jiri@resnulli.us>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 05a324b9

net/ipv4/devinet.c

+42 −16
Original line number Diff line number Diff line
@@ -587,13 +587,16 @@ static void check_lifetime(struct work_struct *work) 
{

	unsigned long now, next, next_sec, next_sched;

	struct in_ifaddr *ifa;

	struct hlist_node *n;

	int i;



	now = jiffies;

	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);



	rcu_read_lock();

	for (i = 0; i < IN4_ADDR_HSIZE; i++) {

		bool change_needed = false;



		rcu_read_lock();

		hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {

			unsigned long age;
@@ -606,16 +609,7 @@ static void check_lifetime(struct work_struct *work) 


			if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&

			    age >= ifa->ifa_valid_lft) {

				struct in_ifaddr **ifap ;



				rtnl_lock();

				for (ifap = &ifa->ifa_dev->ifa_list;

				     *ifap != NULL; ifap = &ifa->ifa_next) {

					if (*ifap == ifa)

						inet_del_ifa(ifa->ifa_dev,

							     ifap, 1);

				}

				rtnl_unlock();

				change_needed = true;

			} else if (ifa->ifa_preferred_lft ==

				   INFINITY_LIFE_TIME) {

				continue;
@@ -625,10 +619,8 @@ static void check_lifetime(struct work_struct *work) 
					next = ifa->ifa_tstamp +

					       ifa->ifa_valid_lft * HZ;



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

					ifa->ifa_flags |= IFA_F_DEPRECATED;

					rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);

				}

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

					change_needed = true;

			} else if (time_before(ifa->ifa_tstamp +

					       ifa->ifa_preferred_lft * HZ,

					       next)) {
@@ -636,8 +628,42 @@ static void check_lifetime(struct work_struct *work) 
				       ifa->ifa_preferred_lft * HZ;

			}

		}

	}

		rcu_read_unlock();

		if (!change_needed)

			continue;

		rtnl_lock();

		hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {

			unsigned long age;



			if (ifa->ifa_flags & IFA_F_PERMANENT)

				continue;



			/* We try to batch several events at once. */

			age = (now - ifa->ifa_tstamp +

			       ADDRCONF_TIMER_FUZZ_MINUS) / HZ;



			if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&

			    age >= ifa->ifa_valid_lft) {

				struct in_ifaddr **ifap;



				for (ifap = &ifa->ifa_dev->ifa_list;

				     *ifap != NULL; ifap = &(*ifap)->ifa_next) {

					if (*ifap == ifa) {

						inet_del_ifa(ifa->ifa_dev,

							     ifap, 1);

						break;

					}

				}

			} else if (ifa->ifa_preferred_lft !=

				   INFINITY_LIFE_TIME &&

				   age >= ifa->ifa_preferred_lft &&

				   !(ifa->ifa_flags & IFA_F_DEPRECATED)) {

				ifa->ifa_flags |= IFA_F_DEPRECATED;

				rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);

			}

		}

		rtnl_unlock();

	}



	next_sec = round_jiffies_up(next);

	next_sched = next;