[PATCH net-next 1/3] xfrm: use time64_t for in-kernel timestamps

From: Arnd Bergmann
Date: Mon Jun 18 2018 - 11:23:15 EST


The lifetime managment uses '__u64' timestamps on the user space
interface, but 'unsigned long' for reading the current time in the kernel
with get_seconds().

While this is probably safe beyond y2038, it will still overflow in 2106,
and the get_seconds() call is deprecated because fo that.

This changes the xfrm time handling to use time64_t consistently, along
with reading the time using the safer ktime_get_real_seconds(). It still
suffers from problems that can happen from a concurrent settimeofday()
call or (to a lesser degree) a leap second update, but since the time
stamps are part of the user API, there is nothing we can do to prevent
that.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
net/xfrm/xfrm_policy.c | 24 ++++++++++++------------
net/xfrm/xfrm_state.c | 10 +++++-----
2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 5f48251c1319..9f4afca8b4f5 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -182,8 +182,8 @@ static inline unsigned long make_jiffies(long secs)
static void xfrm_policy_timer(struct timer_list *t)
{
struct xfrm_policy *xp = from_timer(xp, t, timer);
- unsigned long now = get_seconds();
- long next = LONG_MAX;
+ time64_t now = ktime_get_real_seconds();
+ time64_t next = TIME64_MAX;
int warn = 0;
int dir;

@@ -195,7 +195,7 @@ static void xfrm_policy_timer(struct timer_list *t)
dir = xfrm_policy_id2dir(xp->index);

if (xp->lft.hard_add_expires_seconds) {
- long tmo = xp->lft.hard_add_expires_seconds +
+ time64_t tmo = xp->lft.hard_add_expires_seconds +
xp->curlft.add_time - now;
if (tmo <= 0)
goto expired;
@@ -203,7 +203,7 @@ static void xfrm_policy_timer(struct timer_list *t)
next = tmo;
}
if (xp->lft.hard_use_expires_seconds) {
- long tmo = xp->lft.hard_use_expires_seconds +
+ time64_t tmo = xp->lft.hard_use_expires_seconds +
(xp->curlft.use_time ? : xp->curlft.add_time) - now;
if (tmo <= 0)
goto expired;
@@ -211,7 +211,7 @@ static void xfrm_policy_timer(struct timer_list *t)
next = tmo;
}
if (xp->lft.soft_add_expires_seconds) {
- long tmo = xp->lft.soft_add_expires_seconds +
+ time64_t tmo = xp->lft.soft_add_expires_seconds +
xp->curlft.add_time - now;
if (tmo <= 0) {
warn = 1;
@@ -221,7 +221,7 @@ static void xfrm_policy_timer(struct timer_list *t)
next = tmo;
}
if (xp->lft.soft_use_expires_seconds) {
- long tmo = xp->lft.soft_use_expires_seconds +
+ time64_t tmo = xp->lft.soft_use_expires_seconds +
(xp->curlft.use_time ? : xp->curlft.add_time) - now;
if (tmo <= 0) {
warn = 1;
@@ -233,7 +233,7 @@ static void xfrm_policy_timer(struct timer_list *t)

if (warn)
km_policy_expired(xp, dir, 0, 0);
- if (next != LONG_MAX &&
+ if (next != TIME64_MAX &&
!mod_timer(&xp->timer, jiffies + make_jiffies(next)))
xfrm_pol_hold(xp);

@@ -783,7 +783,7 @@ int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
}
policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
- policy->curlft.add_time = get_seconds();
+ policy->curlft.add_time = ktime_get_real_seconds();
policy->curlft.use_time = 0;
if (!mod_timer(&policy->timer, jiffies + HZ))
xfrm_pol_hold(policy);
@@ -1268,7 +1268,7 @@ int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
old_pol = rcu_dereference_protected(sk->sk_policy[dir],
lockdep_is_held(&net->xfrm.xfrm_policy_lock));
if (pol) {
- pol->curlft.add_time = get_seconds();
+ pol->curlft.add_time = ktime_get_real_seconds();
pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
xfrm_sk_policy_link(pol, dir);
}
@@ -2234,7 +2234,7 @@ struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
}

for (i = 0; i < num_pols; i++)
- pols[i]->curlft.use_time = get_seconds();
+ pols[i]->curlft.use_time = ktime_get_real_seconds();

if (num_xfrms < 0) {
/* Prohibit the flow */
@@ -2446,7 +2446,7 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
return 1;
}

- pol->curlft.use_time = get_seconds();
+ pol->curlft.use_time = ktime_get_real_seconds();

pols[0] = pol;
npols++;
@@ -2460,7 +2460,7 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
return 0;
}
- pols[1]->curlft.use_time = get_seconds();
+ pols[1]->curlft.use_time = ktime_get_real_seconds();
npols++;
}
}
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 8308281f3253..1c2b6fdd9518 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -475,8 +475,8 @@ static enum hrtimer_restart xfrm_timer_handler(struct hrtimer *me)
{
struct tasklet_hrtimer *thr = container_of(me, struct tasklet_hrtimer, timer);
struct xfrm_state *x = container_of(thr, struct xfrm_state, mtimer);
- unsigned long now = get_seconds();
- long next = LONG_MAX;
+ time64_t now = ktime_get_real_seconds();
+ time64_t next = TIME64_MAX;
int warn = 0;
int err = 0;

@@ -537,7 +537,7 @@ static enum hrtimer_restart xfrm_timer_handler(struct hrtimer *me)
if (warn)
km_state_expired(x, 0, 0);
resched:
- if (next != LONG_MAX) {
+ if (next != TIME64_MAX) {
tasklet_hrtimer_start(&x->mtimer, ktime_set(next, 0), HRTIMER_MODE_REL);
}

@@ -577,7 +577,7 @@ struct xfrm_state *xfrm_state_alloc(struct net *net)
tasklet_hrtimer_init(&x->mtimer, xfrm_timer_handler,
CLOCK_BOOTTIME, HRTIMER_MODE_ABS);
timer_setup(&x->rtimer, xfrm_replay_timer_handler, 0);
- x->curlft.add_time = get_seconds();
+ x->curlft.add_time = ktime_get_real_seconds();
x->lft.soft_byte_limit = XFRM_INF;
x->lft.soft_packet_limit = XFRM_INF;
x->lft.hard_byte_limit = XFRM_INF;
@@ -1571,7 +1571,7 @@ EXPORT_SYMBOL(xfrm_state_update);
int xfrm_state_check_expire(struct xfrm_state *x)
{
if (!x->curlft.use_time)
- x->curlft.use_time = get_seconds();
+ x->curlft.use_time = ktime_get_real_seconds();

if (x->curlft.bytes >= x->lft.hard_byte_limit ||
x->curlft.packets >= x->lft.hard_packet_limit) {
--
2.9.0