ipvs: don't show negative times in ip_vs_conn
authorMatteo Croce <mcroce@redhat.com>
Tue, 31 Jul 2018 16:03:33 +0000 (18:03 +0200)
committerPablo Neira Ayuso <pablo@netfilter.org>
Thu, 16 Aug 2018 17:36:57 +0000 (19:36 +0200)
Since commit 500462a9de65 ("timers: Switch to a non-cascading wheel"),
timers duration can last even 12.5% more than the scheduled interval.

IPVS has two handlers, /proc/net/ip_vs_conn and /proc/net/ip_vs_conn_sync,
which shows the remaining time before that a connection expires.
The default expire time for a connection is 60 seconds, and the
expiration timer can fire even 4 seconds later than the scheduled time.
The expiration time is calculated subtracting jiffies to the scheduled
expiration time, and it's shown as a huge number when the timer fires late,
since both values are unsigned.

This can confuse script and tools which relies on it, like ipvsadm:

    root@mcroce-redhat:~# while ipvsadm -lc |grep SYN_RECV; do sleep 1 ; done
    TCP 00:05  SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 00:04  SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 00:03  SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 00:02  SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 00:01  SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 00:00  SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 68719476:44 SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 68719476:43 SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 68719476:42 SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 68719476:41 SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 68719476:40 SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000
    TCP 68719476:39 SYN_RECV    [fc00:1::1]:55732  [fc00:1::2]:8000   [fc00:2000::1]:8000

Signed-off-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
net/netfilter/ipvs/ip_vs_conn.c

index 0edc629..5b2b178 100644 (file)
@@ -1117,24 +1117,28 @@ static int ip_vs_conn_seq_show(struct seq_file *seq, void *v)
 #ifdef CONFIG_IP_VS_IPV6
                if (cp->af == AF_INET6)
                        seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X "
-                               "%s %04X %-11s %7lu%s\n",
+                               "%s %04X %-11s %7u%s\n",
                                ip_vs_proto_name(cp->protocol),
                                &cp->caddr.in6, ntohs(cp->cport),
                                &cp->vaddr.in6, ntohs(cp->vport),
                                dbuf, ntohs(cp->dport),
                                ip_vs_state_name(cp),
-                               (cp->timer.expires-jiffies)/HZ, pe_data);
+                               jiffies_delta_to_msecs(cp->timer.expires -
+                                                      jiffies) / 1000,
+                               pe_data);
                else
 #endif
                        seq_printf(seq,
                                "%-3s %08X %04X %08X %04X"
-                               " %s %04X %-11s %7lu%s\n",
+                               " %s %04X %-11s %7u%s\n",
                                ip_vs_proto_name(cp->protocol),
                                ntohl(cp->caddr.ip), ntohs(cp->cport),
                                ntohl(cp->vaddr.ip), ntohs(cp->vport),
                                dbuf, ntohs(cp->dport),
                                ip_vs_state_name(cp),
-                               (cp->timer.expires-jiffies)/HZ, pe_data);
+                               jiffies_delta_to_msecs(cp->timer.expires -
+                                                      jiffies) / 1000,
+                               pe_data);
        }
        return 0;
 }
@@ -1179,26 +1183,28 @@ static int ip_vs_conn_sync_seq_show(struct seq_file *seq, void *v)
 #ifdef CONFIG_IP_VS_IPV6
                if (cp->af == AF_INET6)
                        seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X "
-                               "%s %04X %-11s %-6s %7lu\n",
+                               "%s %04X %-11s %-6s %7u\n",
                                ip_vs_proto_name(cp->protocol),
                                &cp->caddr.in6, ntohs(cp->cport),
                                &cp->vaddr.in6, ntohs(cp->vport),
                                dbuf, ntohs(cp->dport),
                                ip_vs_state_name(cp),
                                ip_vs_origin_name(cp->flags),
-                               (cp->timer.expires-jiffies)/HZ);
+                               jiffies_delta_to_msecs(cp->timer.expires -
+                                                      jiffies) / 1000);
                else
 #endif
                        seq_printf(seq,
                                "%-3s %08X %04X %08X %04X "
-                               "%s %04X %-11s %-6s %7lu\n",
+                               "%s %04X %-11s %-6s %7u\n",
                                ip_vs_proto_name(cp->protocol),
                                ntohl(cp->caddr.ip), ntohs(cp->cport),
                                ntohl(cp->vaddr.ip), ntohs(cp->vport),
                                dbuf, ntohs(cp->dport),
                                ip_vs_state_name(cp),
                                ip_vs_origin_name(cp->flags),
-                               (cp->timer.expires-jiffies)/HZ);
+                               jiffies_delta_to_msecs(cp->timer.expires -
+                                                      jiffies) / 1000);
        }
        return 0;
 }