Dave,

One more late-breaking fix in the nl80211 code, the fix for the
nl80211_fam.attrbuf race Linus ran into and analysed.  Hopefully it
looks familiar... :-)

Let me know if there are problems!

John

---

The following changes since commit eb064c3b49931dc73bba59887019c7f5cb97d322:

  vxlan: fix check for migration of static entry (2013-06-19 00:50:58 -0700)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless.git for-davem

for you to fetch changes up to 4067c666f2dccf56f5db5c182713e68c40d46013:

  Merge branch 'master' of 
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem 
(2013-06-19 15:24:36 -0400)

----------------------------------------------------------------

Johannes Berg (1):
      nl80211: fix attrbuf access race by allocating a separate one

John W. Linville (2):
      Merge branch 'for-john' of git://git.kernel.org/.../jberg/mac80211
      Merge branch 'master' of git://git.kernel.org/.../linville/wireless into 
for-davem

 net/wireless/nl80211.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index d5aed3b..b14b7e3 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1564,12 +1564,17 @@ static int nl80211_dump_wiphy(struct sk_buff *skb, 
struct netlink_callback *cb)
        struct cfg80211_registered_device *dev;
        s64 filter_wiphy = -1;
        bool split = false;
-       struct nlattr **tb = nl80211_fam.attrbuf;
+       struct nlattr **tb;
        int res;
 
+       /* will be zeroed in nlmsg_parse() */
+       tb = kmalloc(sizeof(*tb) * (NL80211_ATTR_MAX + 1), GFP_KERNEL);
+       if (!tb)
+               return -ENOMEM;
+
        mutex_lock(&cfg80211_mutex);
        res = nlmsg_parse(cb->nlh, GENL_HDRLEN + nl80211_fam.hdrsize,
-                         tb, nl80211_fam.maxattr, nl80211_policy);
+                         tb, NL80211_ATTR_MAX, nl80211_policy);
        if (res == 0) {
                split = tb[NL80211_ATTR_SPLIT_WIPHY_DUMP];
                if (tb[NL80211_ATTR_WIPHY])
@@ -1583,6 +1588,7 @@ static int nl80211_dump_wiphy(struct sk_buff *skb, struct 
netlink_callback *cb)
                        netdev = dev_get_by_index(sock_net(skb->sk), ifidx);
                        if (!netdev) {
                                mutex_unlock(&cfg80211_mutex);
+                               kfree(tb);
                                return -ENODEV;
                        }
                        if (netdev->ieee80211_ptr) {
@@ -1593,6 +1599,7 @@ static int nl80211_dump_wiphy(struct sk_buff *skb, struct 
netlink_callback *cb)
                        dev_put(netdev);
                }
        }
+       kfree(tb);
 
        list_for_each_entry(dev, &cfg80211_rdev_list, list) {
                if (!net_eq(wiphy_net(&dev->wiphy), sock_net(skb->sk)))
-- 
John W. Linville                Someday the world will need a hero, and you
linvi...@tuxdriver.com                  might be all we have.  Be ready.

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