Merge tag 'v4.2-rc8' into drm-next

Linux 4.2-rc8

Backmerge required for Intel so they can fix their -next tree up properly.

12 files changed, 132 insertions, 90 deletions

diff --git a/net/9p/client.c b/net/9p/client.c
index 498454b3c06c..ea79ee9a7348 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -1541,6 +1541,7 @@ p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
         struct p9_client *clnt = fid->clnt;
         struct p9_req_t *req;
         int total = 0;
+        *err = 0;
 
         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
                    fid->fid, (unsigned long long) offset, (int)iov_iter_count(to));
@@ -1620,6 +1621,7 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
         struct p9_client *clnt = fid->clnt;
         struct p9_req_t *req;
         int total = 0;
+        *err = 0;
 
         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
                                 fid->fid, (unsigned long long) offset,
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index 5e953297d3b2..5809b39c1922 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -595,8 +595,11 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
         /* increase the refcounter of the related vlan */
         vlan = batadv_softif_vlan_get(bat_priv, vid);
         if (WARN(!vlan, "adding TT local entry %pM to non-existent VLAN %d",
-                 addr, BATADV_PRINT_VID(vid)))
+                 addr, BATADV_PRINT_VID(vid))) {
+                kfree(tt_local);
+                tt_local = NULL;
                 goto out;
+        }
 
         batadv_dbg(BATADV_DBG_TT, bat_priv,
                    "Creating new local tt entry: %pM (vid: %d, ttvn: %d)\n",
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 0b39dcc65b94..1285eaf5dc22 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1591,7 +1591,7 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br,
                 break;
         }
 
-        if (skb_trimmed)
+        if (skb_trimmed && skb_trimmed != skb)
                 kfree_skb(skb_trimmed);
 
         return err;
@@ -1636,7 +1636,7 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
                 break;
         }
 
-        if (skb_trimmed)
+        if (skb_trimmed && skb_trimmed != skb)
                 kfree_skb(skb_trimmed);
 
         return err;
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index b6a19ca0f99e..7b84330e5d30 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -340,7 +340,7 @@ struct sk_buff *build_skb(void *data, unsigned int frag_size)
 
         if (skb && frag_size) {
                 skb->head_frag = 1;
-                if (virt_to_head_page(data)->pfmemalloc)
+                if (page_is_pfmemalloc(virt_to_head_page(data)))
                         skb->pfmemalloc = 1;
         }
         return skb;
@@ -4022,8 +4022,8 @@ EXPORT_SYMBOL(skb_checksum_setup);
  * Otherwise returns the provided skb. Returns NULL in error cases
  * (e.g. transport_len exceeds skb length or out-of-memory).
  *
- * Caller needs to set the skb transport header and release the returned skb.
- * Provided skb is consumed.
+ * Caller needs to set the skb transport header and free any returned skb if it
+ * differs from the provided skb.
  */
 static struct sk_buff *skb_checksum_maybe_trim(struct sk_buff *skb,
                                                unsigned int transport_len)
@@ -4032,16 +4032,12 @@ static struct sk_buff *skb_checksum_maybe_trim(struct sk_buff *skb,
         unsigned int len = skb_transport_offset(skb) + transport_len;
         int ret;
 
-        if (skb->len < len) {
-                kfree_skb(skb);
+        if (skb->len < len)
                 return NULL;
-        } else if (skb->len == len) {
+        else if (skb->len == len)
                 return skb;
-        }
 
         skb_chk = skb_clone(skb, GFP_ATOMIC);
-        kfree_skb(skb);
-
         if (!skb_chk)
                 return NULL;
 
@@ -4066,8 +4062,8 @@ static struct sk_buff *skb_checksum_maybe_trim(struct sk_buff *skb,
  * If the skb has data beyond the given transport length, then a
  * trimmed & cloned skb is checked and returned.
  *
- * Caller needs to set the skb transport header and release the returned skb.
- * Provided skb is consumed.
+ * Caller needs to set the skb transport header and free any returned skb if it
+ * differs from the provided skb.
  */
 struct sk_buff *skb_checksum_trimmed(struct sk_buff *skb,
                                      unsigned int transport_len,
@@ -4079,23 +4075,26 @@ struct sk_buff *skb_checksum_trimmed(struct sk_buff *skb,
 
         skb_chk = skb_checksum_maybe_trim(skb, transport_len);
         if (!skb_chk)
-                return NULL;
+                goto err;
 
-        if (!pskb_may_pull(skb_chk, offset)) {
-                kfree_skb(skb_chk);
-                return NULL;
-        }
+        if (!pskb_may_pull(skb_chk, offset))
+                goto err;
 
         __skb_pull(skb_chk, offset);
         ret = skb_chkf(skb_chk);
         __skb_push(skb_chk, offset);
 
-        if (ret) {
-                kfree_skb(skb_chk);
-                return NULL;
-        }
+        if (ret)
+                goto err;
 
         return skb_chk;
+
+err:
+        if (skb_chk && skb_chk != skb)
+                kfree_skb(skb_chk);
+
+        return NULL;
+
 }
 EXPORT_SYMBOL(skb_checksum_trimmed);
 
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 37c4bb89a708..b0c6258ffb79 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -2465,7 +2465,7 @@ static struct key_vector *fib_route_get_idx(struct fib_route_iter *iter,
                 key = l->key + 1;
                 iter->pos++;
 
-                if (pos-- <= 0)
+                if (--pos <= 0)
                         break;
 
                 l = NULL;
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 651cdf648ec4..9fdfd9deac11 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1435,33 +1435,35 @@ static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
         struct sk_buff *skb_chk;
         unsigned int transport_len;
         unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
-        int ret;
+        int ret = -EINVAL;
 
         transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb);
 
-        skb_get(skb);
         skb_chk = skb_checksum_trimmed(skb, transport_len,
                                        ip_mc_validate_checksum);
         if (!skb_chk)
-                return -EINVAL;
+                goto err;
 
-        if (!pskb_may_pull(skb_chk, len)) {
-                kfree_skb(skb_chk);
-                return -EINVAL;
-        }
+        if (!pskb_may_pull(skb_chk, len))
+                goto err;
 
         ret = ip_mc_check_igmp_msg(skb_chk);
-        if (ret) {
-                kfree_skb(skb_chk);
-                return ret;
-        }
+        if (ret)
+                goto err;
 
         if (skb_trimmed)
                 *skb_trimmed = skb_chk;
-        else
+        /* free now unneeded clone */
+        else if (skb_chk != skb)
                 kfree_skb(skb_chk);
 
-        return 0;
+        ret = 0;
+
+err:
+        if (ret && skb_chk && skb_chk != skb)
+                kfree_skb(skb_chk);
+
+        return ret;
 }
 
 /**
@@ -1470,7 +1472,7 @@ static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
  * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional)
  *
  * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
- * skb network and transport headers accordingly and returns zero.
+ * skb transport header accordingly and returns zero.
  *
  * -EINVAL: A broken packet was detected, i.e. it violates some internet
  *  standard
@@ -1485,7 +1487,8 @@ static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
  * to leave the original skb and its full frame unchanged (which might be
  * desirable for layer 2 frame jugglers).
  *
- * The caller needs to release a reference count from any returned skb_trimmed.
+ * Caller needs to set the skb network header and free any returned skb if it
+ * differs from the provided skb.
  */
 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
 {
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 05e3145f7dc3..134957159c27 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -593,7 +593,7 @@ static bool reqsk_queue_unlink(struct request_sock_queue *queue,
         }
 
         spin_unlock(&queue->syn_wait_lock);
-        if (del_timer_sync(&req->rsk_timer))
+        if (timer_pending(&req->rsk_timer) && del_timer_sync(&req->rsk_timer))
                 reqsk_put(req);
         return found;
 }
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 433231ccfb17..0330ab2e2b63 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -41,8 +41,6 @@ static int tcp_syn_retries_min = 1;
 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
 static int ip_ping_group_range_min[] = { 0, 0 };
 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
-static int min_sndbuf = SOCK_MIN_SNDBUF;
-static int min_rcvbuf = SOCK_MIN_RCVBUF;
 
 /* Update system visible IP port range */
 static void set_local_port_range(struct net *net, int range[2])
@@ -530,7 +528,7 @@ static struct ctl_table ipv4_table[] = {
                 .maxlen         = sizeof(sysctl_tcp_wmem),
                 .mode           = 0644,
                 .proc_handler   = proc_dointvec_minmax,
-                .extra1         = &min_sndbuf,
+                .extra1         = &one,
         },
         {
                 .procname       = "tcp_notsent_lowat",
@@ -545,7 +543,7 @@ static struct ctl_table ipv4_table[] = {
                 .maxlen         = sizeof(sysctl_tcp_rmem),
                 .mode           = 0644,
                 .proc_handler   = proc_dointvec_minmax,
-                .extra1         = &min_rcvbuf,
+                .extra1         = &one,
         },
         {
                 .procname       = "tcp_app_win",
@@ -758,7 +756,7 @@ static struct ctl_table ipv4_table[] = {
                 .maxlen         = sizeof(sysctl_udp_rmem_min),
                 .mode           = 0644,
                 .proc_handler   = proc_dointvec_minmax,
-                .extra1         = &min_rcvbuf,
+                .extra1         = &one
         },
         {
                 .procname       = "udp_wmem_min",
@@ -766,7 +764,7 @@ static struct ctl_table ipv4_table[] = {
                 .maxlen         = sizeof(sysctl_udp_wmem_min),
                 .mode           = 0644,
                 .proc_handler   = proc_dointvec_minmax,
-                .extra1         = &min_sndbuf,
+                .extra1         = &one
         },
         { }
 };
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 55d19861ab20..548c6237b1e7 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -172,6 +172,8 @@ static void rt6_free_pcpu(struct rt6_info *non_pcpu_rt)
                         *ppcpu_rt = NULL;
                 }
         }
+
+        non_pcpu_rt->rt6i_pcpu = NULL;
 }
 
 static void rt6_release(struct rt6_info *rt)
diff --git a/net/ipv6/mcast_snoop.c b/net/ipv6/mcast_snoop.c
index df8afe5ab31e..9405b04eecc6 100644
--- a/net/ipv6/mcast_snoop.c
+++ b/net/ipv6/mcast_snoop.c
@@ -143,34 +143,36 @@ static int __ipv6_mc_check_mld(struct sk_buff *skb,
         struct sk_buff *skb_chk = NULL;
         unsigned int transport_len;
         unsigned int len = skb_transport_offset(skb) + sizeof(struct mld_msg);
-        int ret;
+        int ret = -EINVAL;
 
         transport_len = ntohs(ipv6_hdr(skb)->payload_len);
         transport_len -= skb_transport_offset(skb) - sizeof(struct ipv6hdr);
 
-        skb_get(skb);
         skb_chk = skb_checksum_trimmed(skb, transport_len,
                                        ipv6_mc_validate_checksum);
         if (!skb_chk)
-                return -EINVAL;
+                goto err;
 
-        if (!pskb_may_pull(skb_chk, len)) {
-                kfree_skb(skb_chk);
-                return -EINVAL;
-        }
+        if (!pskb_may_pull(skb_chk, len))
+                goto err;
 
         ret = ipv6_mc_check_mld_msg(skb_chk);
-        if (ret) {
-                kfree_skb(skb_chk);
-                return ret;
-        }
+        if (ret)
+                goto err;
 
         if (skb_trimmed)
                 *skb_trimmed = skb_chk;
-        else
+        /* free now unneeded clone */
+        else if (skb_chk != skb)
                 kfree_skb(skb_chk);
 
-        return 0;
+        ret = 0;
+
+err:
+        if (ret && skb_chk && skb_chk != skb)
+                kfree_skb(skb_chk);
+
+        return ret;
 }
 
 /**
@@ -179,7 +181,7 @@ static int __ipv6_mc_check_mld(struct sk_buff *skb,
  * @skb_trimmed: to store an skb pointer trimmed to IPv6 packet tail (optional)
  *
  * Checks whether an IPv6 packet is a valid MLD packet. If so sets
- * skb network and transport headers accordingly and returns zero.
+ * skb transport header accordingly and returns zero.
  *
  * -EINVAL: A broken packet was detected, i.e. it violates some internet
  *  standard
@@ -194,7 +196,8 @@ static int __ipv6_mc_check_mld(struct sk_buff *skb,
  * to leave the original skb and its full frame unchanged (which might be
  * desirable for layer 2 frame jugglers).
  *
- * The caller needs to release a reference count from any returned skb_trimmed.
+ * Caller needs to set the skb network header and free any returned skb if it
+ * differs from the provided skb.
  */
 int ipv6_mc_check_mld(struct sk_buff *skb, struct sk_buff **skb_trimmed)
 {
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);
 
diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c
index 247552a7f6c2..3ece7d1034c8 100644
--- a/net/mac80211/rc80211_minstrel.c
+++ b/net/mac80211/rc80211_minstrel.c
@@ -92,14 +92,15 @@ int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma)
 static inline void
 minstrel_sort_best_tp_rates(struct minstrel_sta_info *mi, int i, u8 *tp_list)
 {
-        int j = MAX_THR_RATES;
-        struct minstrel_rate_stats *tmp_mrs = &mi->r[j - 1].stats;
+        int j;
+        struct minstrel_rate_stats *tmp_mrs;
         struct minstrel_rate_stats *cur_mrs = &mi->r[i].stats;
 
-        while (j > 0 && (minstrel_get_tp_avg(&mi->r[i], cur_mrs->prob_ewma) >
-               minstrel_get_tp_avg(&mi->r[tp_list[j - 1]], tmp_mrs->prob_ewma))) {
-                j--;
+        for (j = MAX_THR_RATES; j > 0; --j) {
                 tmp_mrs = &mi->r[tp_list[j - 1]].stats;
+                if (minstrel_get_tp_avg(&mi->r[i], cur_mrs->prob_ewma) <=
+                    minstrel_get_tp_avg(&mi->r[tp_list[j - 1]], tmp_mrs->prob_ewma))
+                        break;
         }
 
         if (j < MAX_THR_RATES - 1)