[NET]: /proc/net/if_inet6 may drop some data.

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 00f6df4bc133c3f1f2f5c272abcf5ae5204a52c9..286e5eef4ebb508b4edb253c2b2d82630e421a0b 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2149,59 +2149,65 @@ struct if6_iter_state {
        int bucket;
 };
 
-static inline struct inet6_ifaddr *if6_get_bucket(struct seq_file *seq, loff_t *pos)
+static struct inet6_ifaddr *if6_get_first(struct seq_file *seq)
 {
-       int i;
        struct inet6_ifaddr *ifa = NULL;
-       loff_t l = *pos;
        struct if6_iter_state *state = seq->private;
 
-       for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket)
-               for (i = 0, ifa = inet6_addr_lst[state->bucket]; ifa; ++i, ifa=ifa->lst_next) {
-                       if (l--)
-                               continue;
-                       *pos = i;
-                       goto out;
-               }
-out:
+       for (state->bucket = 0; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
+               ifa = inet6_addr_lst[state->bucket];
+               if (ifa)
+                       break;
+       }
+       return ifa;
+}
+
+static struct inet6_ifaddr *if6_get_next(struct seq_file *seq, struct inet6_ifaddr *ifa)
+{
+       struct if6_iter_state *state = seq->private;
+
+       ifa = ifa->lst_next;
+try_again:
+       if (!ifa && ++state->bucket < IN6_ADDR_HSIZE) {
+               ifa = inet6_addr_lst[state->bucket];
+               goto try_again;
+       }
        return ifa;
 }
 
+static struct inet6_ifaddr *if6_get_idx(struct seq_file *seq, loff_t pos)
+{
+       struct inet6_ifaddr *ifa = if6_get_first(seq);
+
+       if (ifa)
+               while(pos && (ifa = if6_get_next(seq, ifa)) != NULL)
+                       --pos;
+       return pos ? NULL : ifa;
+}
+
 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
 {
        read_lock_bh(&addrconf_hash_lock);
-       return *pos ? if6_get_bucket(seq, pos) : SEQ_START_TOKEN;
+       return if6_get_idx(seq, *pos);
 }
 
 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
        struct inet6_ifaddr *ifa;
-       struct if6_iter_state *state;
-
-       if (v == SEQ_START_TOKEN) {
-               ifa = if6_get_bucket(seq, pos);
-               goto out;
-       }
-
-       state = seq->private;
 
-       ifa = v;
-       ifa = ifa->lst_next;
-       if (ifa)
-               goto out;
-
-       if (++state->bucket >= IN6_ADDR_HSIZE)
-               goto out;
-
-       *pos = 0;
-       ifa = if6_get_bucket(seq, pos);
-out:
+       ifa = if6_get_next(seq, v);
        ++*pos;
        return ifa;
 }
 
-static inline void if6_iface_seq_show(struct seq_file *seq, struct inet6_ifaddr *ifp)
+static void if6_seq_stop(struct seq_file *seq, void *v)
+{
+       read_unlock_bh(&addrconf_hash_lock);
+}
+
+static int if6_seq_show(struct seq_file *seq, void *v)
 {
+       struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
        seq_printf(seq,
                   "%04x%04x%04x%04x%04x%04x%04x%04x %02x %02x %02x %02x %8s\n",
                   NIP6(ifp->addr),
@@ -2210,22 +2216,9 @@ static inline void if6_iface_seq_show(struct seq_file *seq, struct inet6_ifaddr
                   ifp->scope,
                   ifp->flags,
                   ifp->idev->dev->name);
-}
-
-static int if6_seq_show(struct seq_file *seq, void *v)
-{
-       if (v == SEQ_START_TOKEN)
-               return 0;
-       else
-               if6_iface_seq_show(seq, v);
        return 0;
 }
 
-static void if6_seq_stop(struct seq_file *seq, void *v)
-{
-       read_unlock_bh(&addrconf_hash_lock);
-}
-
 static struct seq_operations if6_seq_ops = {
        .start  = if6_seq_start,
        .next   = if6_seq_next,