Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Conflicts:
	drivers/net/bonding/bond_main.c
	drivers/net/ethernet/mellanox/mlxsw/spectrum.h
	drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c

The bond_main.c and mellanox switch conflicts were cases of
overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 20 insertions, 4 deletions

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index e6d35569f757..c5bf5ef2bf89 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1513,6 +1513,21 @@ static void unix_destruct_scm(struct sk_buff *skb)
         sock_wfree(skb);
 }
 
+/*
+ * The "user->unix_inflight" variable is protected by the garbage
+ * collection lock, and we just read it locklessly here. If you go
+ * over the limit, there might be a tiny race in actually noticing
+ * it across threads. Tough.
+ */
+static inline bool too_many_unix_fds(struct task_struct *p)
+{
+        struct user_struct *user = current_user();
+
+        if (unlikely(user->unix_inflight > task_rlimit(p, RLIMIT_NOFILE)))
+                return !capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN);
+        return false;
+}
+
 #define MAX_RECURSION_LEVEL 4
 
 static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
@@ -1521,6 +1536,9 @@ static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
         unsigned char max_level = 0;
         int unix_sock_count = 0;
 
+        if (too_many_unix_fds(current))
+                return -ETOOMANYREFS;
+
         for (i = scm->fp->count - 1; i >= 0; i--) {
                 struct sock *sk = unix_get_socket(scm->fp->fp[i]);
 
@@ -1542,10 +1560,8 @@ static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
         if (!UNIXCB(skb).fp)
                 return -ENOMEM;
 
-        if (unix_sock_count) {
-                for (i = scm->fp->count - 1; i >= 0; i--)
-                        unix_inflight(scm->fp->fp[i]);
-        }
+        for (i = scm->fp->count - 1; i >= 0; i--)
+                unix_inflight(scm->fp->fp[i]);
         return max_level;
 }