net: ipv4: Convert IP network timestamps to be y2038 safe
ICMP timestamp messages and IP source route options require
timestamps to be in milliseconds modulo 24 hours from
midnight UT format.
Add inet_current_timestamp() function to support this. The function
returns the required timestamp in network byte order.
Timestamp calculation is also changed to call ktime_get_real_ts64()
which uses struct timespec64. struct timespec64 is y2038 safe.
Previously it called getnstimeofday() which uses struct timespec.
struct timespec is not y2038 safe.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip.h b/include/net/ip.h
index cbb134b..fad74d3 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -240,6 +240,8 @@
}
#endif
+__be32 inet_current_timestamp(void);
+
/* From inetpeer.c */
extern int inet_peer_threshold;
extern int inet_peer_minttl;
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 209d1ed..0cc923f 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1380,6 +1380,32 @@
return pp;
}
+#define SECONDS_PER_DAY 86400
+
+/* inet_current_timestamp - Return IP network timestamp
+ *
+ * Return milliseconds since midnight in network byte order.
+ */
+__be32 inet_current_timestamp(void)
+{
+ u32 secs;
+ u32 msecs;
+ struct timespec64 ts;
+
+ ktime_get_real_ts64(&ts);
+
+ /* Get secs since midnight. */
+ (void)div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs);
+ /* Convert to msecs. */
+ msecs = secs * MSEC_PER_SEC;
+ /* Convert nsec to msec. */
+ msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC;
+
+ /* Convert to network byte order. */
+ return htons(msecs);
+}
+EXPORT_SYMBOL(inet_current_timestamp);
+
int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
{
if (sk->sk_family == AF_INET)
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 36e2697..6333489 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -931,7 +931,6 @@
*/
static bool icmp_timestamp(struct sk_buff *skb)
{
- struct timespec tv;
struct icmp_bxm icmp_param;
/*
* Too short.
@@ -942,9 +941,7 @@
/*
* Fill in the current time as ms since midnight UT:
*/
- getnstimeofday(&tv);
- icmp_param.data.times[1] = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC +
- tv.tv_nsec / NSEC_PER_MSEC);
+ icmp_param.data.times[1] = inet_current_timestamp();
icmp_param.data.times[2] = icmp_param.data.times[1];
if (skb_copy_bits(skb, 0, &icmp_param.data.times[0], 4))
BUG();
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index bd24679..4d158ff 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -58,10 +58,9 @@
if (opt->ts_needaddr)
ip_rt_get_source(iph+opt->ts+iph[opt->ts+2]-9, skb, rt);
if (opt->ts_needtime) {
- struct timespec tv;
__be32 midtime;
- getnstimeofday(&tv);
- midtime = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC + tv.tv_nsec / NSEC_PER_MSEC);
+
+ midtime = inet_current_timestamp();
memcpy(iph+opt->ts+iph[opt->ts+2]-5, &midtime, 4);
}
return;
@@ -415,11 +414,10 @@
break;
}
if (timeptr) {
- struct timespec tv;
- u32 midtime;
- getnstimeofday(&tv);
- midtime = (tv.tv_sec % 86400) * MSEC_PER_SEC + tv.tv_nsec / NSEC_PER_MSEC;
- put_unaligned_be32(midtime, timeptr);
+ __be32 midtime;
+
+ midtime = inet_current_timestamp();
+ memcpy(timeptr, &midtime, 4);
opt->is_changed = 1;
}
} else if ((optptr[3]&0xF) != IPOPT_TS_PRESPEC) {