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authorLinus Torvalds <torvalds@linux-foundation.org>2015-08-20 12:32:28 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-08-20 12:32:28 -0700
commit28e55d072312f8b418b58ab379ac0a8667ddbfce (patch)
tree823929fee70178ef05de98d0fafb044606a95539 /net/ipv6/route.c
parent3d3e66ba2ced6c5ba7d960f106ba2d3a4444c4ab (diff)
parentfd7dec25a18f495e50d2040398fd263836ff3b28 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller: 1) Out of bounds array access in 802.11 minstrel code, from Adrien Schildknecht. 2) Don't use skb_get() in IGMP/MLD code paths, as this makes pskb_may_pull() BUG. From Linus Luessing. 3) Fix off by one in ipv4 route dumping code, from Andy Whitcroft. 4) Fix deadlock in reqsk_queue_unlink(), from Eric Dumazet. 5) Fix ppp device deregistration wrt. netns deletion, from Guillaume Nault. 6) Fix deadlock when creating per-cpu ipv6 routes, from Martin KaFai Lau. 7) Fix memory leak in batman-adv code, from Sven Eckelmann. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: batman-adv: Fix memory leak on tt add with invalid vlan net: phy: fix semicolon.cocci warnings net: qmi_wwan: add HP lt4111 LTE/EV-DO/HSPA+ Gobi 4G Module be2net: avoid vxlan offloading on multichannel configs ipv6: Fix a potential deadlock when creating pcpu rt ipv6: Add rt6_make_pcpu_route() ipv6: Remove un-used argument from ip6_dst_alloc() net: phy: workaround for buggy cable detection by LAN8700 after cable plugging net: ethernet: micrel: fix an error code ppp: fix device unregistration upon netns deletion net: phy: fix PHY_RUNNING in phy_state_machine Revert "net: limit tcp/udp rmem/wmem to SOCK_{RCV,SND}BUF_MIN" inet: fix potential deadlock in reqsk_queue_unlink() gianfar: Restore link state settings after MAC reset ipv4: off-by-one in continuation handling in /proc/net/route net: fix wrong skb_get() usage / crash in IGMP/MLD parsing code mac80211: fix invalid read in minstrel_sort_best_tp_rates()
Diffstat (limited to 'net/ipv6/route.c')
-rw-r--r--net/ipv6/route.c79
1 files changed, 55 insertions, 24 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 9de4d2bcd916..d15586490cec 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -318,8 +318,7 @@ static const struct rt6_info ip6_blk_hole_entry_template = {
/* allocate dst with ip6_dst_ops */
static struct rt6_info *__ip6_dst_alloc(struct net *net,
struct net_device *dev,
- int flags,
- struct fib6_table *table)
+ int flags)
{
struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
0, DST_OBSOLETE_FORCE_CHK, flags);
@@ -336,10 +335,9 @@ static struct rt6_info *__ip6_dst_alloc(struct net *net,
static struct rt6_info *ip6_dst_alloc(struct net *net,
struct net_device *dev,
- int flags,
- struct fib6_table *table)
+ int flags)
{
- struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags, table);
+ struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
if (rt) {
rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
@@ -950,8 +948,7 @@ static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
ort = (struct rt6_info *)ort->dst.from;
- rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev,
- 0, ort->rt6i_table);
+ rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
if (!rt)
return NULL;
@@ -983,8 +980,7 @@ static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
struct rt6_info *pcpu_rt;
pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
- rt->dst.dev, rt->dst.flags,
- rt->rt6i_table);
+ rt->dst.dev, rt->dst.flags);
if (!pcpu_rt)
return NULL;
@@ -997,32 +993,53 @@ static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
/* It should be called with read_lock_bh(&tb6_lock) acquired */
static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
{
- struct rt6_info *pcpu_rt, *prev, **p;
+ struct rt6_info *pcpu_rt, **p;
p = this_cpu_ptr(rt->rt6i_pcpu);
pcpu_rt = *p;
- if (pcpu_rt)
- goto done;
+ if (pcpu_rt) {
+ dst_hold(&pcpu_rt->dst);
+ rt6_dst_from_metrics_check(pcpu_rt);
+ }
+ return pcpu_rt;
+}
+
+static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
+{
+ struct fib6_table *table = rt->rt6i_table;
+ struct rt6_info *pcpu_rt, *prev, **p;
pcpu_rt = ip6_rt_pcpu_alloc(rt);
if (!pcpu_rt) {
struct net *net = dev_net(rt->dst.dev);
- pcpu_rt = net->ipv6.ip6_null_entry;
- goto done;
+ dst_hold(&net->ipv6.ip6_null_entry->dst);
+ return net->ipv6.ip6_null_entry;
}
- prev = cmpxchg(p, NULL, pcpu_rt);
- if (prev) {
- /* If someone did it before us, return prev instead */
+ read_lock_bh(&table->tb6_lock);
+ if (rt->rt6i_pcpu) {
+ p = this_cpu_ptr(rt->rt6i_pcpu);
+ prev = cmpxchg(p, NULL, pcpu_rt);
+ if (prev) {
+ /* If someone did it before us, return prev instead */
+ dst_destroy(&pcpu_rt->dst);
+ pcpu_rt = prev;
+ }
+ } else {
+ /* rt has been removed from the fib6 tree
+ * before we have a chance to acquire the read_lock.
+ * In this case, don't brother to create a pcpu rt
+ * since rt is going away anyway. The next
+ * dst_check() will trigger a re-lookup.
+ */
dst_destroy(&pcpu_rt->dst);
- pcpu_rt = prev;
+ pcpu_rt = rt;
}
-
-done:
dst_hold(&pcpu_rt->dst);
rt6_dst_from_metrics_check(pcpu_rt);
+ read_unlock_bh(&table->tb6_lock);
return pcpu_rt;
}
@@ -1097,9 +1114,22 @@ redo_rt6_select:
rt->dst.lastuse = jiffies;
rt->dst.__use++;
pcpu_rt = rt6_get_pcpu_route(rt);
- read_unlock_bh(&table->tb6_lock);
+
+ if (pcpu_rt) {
+ read_unlock_bh(&table->tb6_lock);
+ } else {
+ /* We have to do the read_unlock first
+ * because rt6_make_pcpu_route() may trigger
+ * ip6_dst_gc() which will take the write_lock.
+ */
+ dst_hold(&rt->dst);
+ read_unlock_bh(&table->tb6_lock);
+ pcpu_rt = rt6_make_pcpu_route(rt);
+ dst_release(&rt->dst);
+ }
return pcpu_rt;
+
}
}
@@ -1555,7 +1585,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
if (unlikely(!idev))
return ERR_PTR(-ENODEV);
- rt = ip6_dst_alloc(net, dev, 0, NULL);
+ rt = ip6_dst_alloc(net, dev, 0);
if (unlikely(!rt)) {
in6_dev_put(idev);
dst = ERR_PTR(-ENOMEM);
@@ -1742,7 +1772,8 @@ int ip6_route_add(struct fib6_config *cfg)
if (!table)
goto out;
- rt = ip6_dst_alloc(net, NULL, (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT, table);
+ rt = ip6_dst_alloc(net, NULL,
+ (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
if (!rt) {
err = -ENOMEM;
@@ -2399,7 +2430,7 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
{
struct net *net = dev_net(idev->dev);
struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
- DST_NOCOUNT, NULL);
+ DST_NOCOUNT);
if (!rt)
return ERR_PTR(-ENOMEM);