Revert "ipv6: remove max_size check inline with ipv4"
This reverts commit dd56c5790dc3484f3c89fd4e21735c796a82b40d which is
commit af6d10345ca76670c1b7c37799f0d5576ccef277 upstream.
It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.
Bug: 161946584
Change-Id: I7e768b45f1b301807a89234d2af0fd025a13396e
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
diff --git a/include/net/dst_ops.h b/include/net/dst_ops.h
index 632086b..88ff7bb 100644
--- a/include/net/dst_ops.h
+++ b/include/net/dst_ops.h
@@ -16,7 +16,7 @@
unsigned short family;
unsigned int gc_thresh;
- void (*gc)(struct dst_ops *ops);
+ int (*gc)(struct dst_ops *ops);
struct dst_entry * (*check)(struct dst_entry *, __u32 cookie);
unsigned int (*default_advmss)(const struct dst_entry *);
unsigned int (*mtu)(const struct dst_entry *);
diff --git a/net/core/dst.c b/net/core/dst.c
index 453ec8a..fb3bcba 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -83,8 +83,12 @@
if (ops->gc &&
!(flags & DST_NOCOUNT) &&
- dst_entries_get_fast(ops) > ops->gc_thresh)
- ops->gc(ops);
+ dst_entries_get_fast(ops) > ops->gc_thresh) {
+ if (ops->gc(ops)) {
+ pr_notice_ratelimited("Route cache is full: consider increasing sysctl net.ipv6.route.max_size.\n");
+ return NULL;
+ }
+ }
dst = kmem_cache_alloc(ops->kmem_cachep, GFP_ATOMIC);
if (!dst)
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ca833f3..9b9f72d 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -89,7 +89,7 @@
static void ip6_dst_destroy(struct dst_entry *);
static void ip6_dst_ifdown(struct dst_entry *,
struct net_device *dev, int how);
-static void ip6_dst_gc(struct dst_ops *ops);
+static int ip6_dst_gc(struct dst_ops *ops);
static int ip6_pkt_discard(struct sk_buff *skb);
static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
@@ -3184,20 +3184,22 @@
return dst;
}
-static void ip6_dst_gc(struct dst_ops *ops)
+static int ip6_dst_gc(struct dst_ops *ops)
{
struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
+ int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
int entries;
entries = dst_entries_get_fast(ops);
- if (entries > ops->gc_thresh)
+ if (entries > rt_max_size)
entries = dst_entries_get_slow(ops);
- if (time_after(rt_last_gc + rt_min_interval, jiffies))
+ if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
+ entries <= rt_max_size)
goto out;
net->ipv6.ip6_rt_gc_expire++;
@@ -3207,6 +3209,7 @@
net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
out:
net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
+ return entries > rt_max_size;
}
static int ip6_nh_lookup_table(struct net *net, struct fib6_config *cfg,
@@ -6336,7 +6339,7 @@
#endif
net->ipv6.sysctl.flush_delay = 0;
- net->ipv6.sysctl.ip6_rt_max_size = INT_MAX;
+ net->ipv6.sysctl.ip6_rt_max_size = 4096;
net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
