вот так выглядит более правильно
diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 3c8af63..7ca2e4f 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -6,7 +6,7 @@
#include <linux/mutex.h>
#include <net/sock.h>

-extern void unix_inflight(struct file *fp);
+extern int unix_inflight(struct file *fp);
extern void unix_notinflight(struct file *fp);
extern void unix_gc(void);
extern void wait_for_unix_gc(void);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index cb552e2..673ea9c 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -572,11 +572,17 @@ static struct proto unix_proto = {
  */
static struct lock_class_key af_unix_sk_receive_queue_lock_key;

+#define UNIX_INFLIGHT_TRIGGER_GC 128
+extern bool gc_in_progress;
+
static struct sock * unix_create1(struct socket *sock)
{
        struct sock *sk = NULL;
        struct unix_sock *u;

+       if (atomic_read(&unix_tot_inflight) > UNIX_INFLIGHT_TRIGGER_GC && !gc_in_progress)
+               unix_gc();
+
        if (atomic_read(&unix_nr_socks) >= 2*get_max_files())
                goto out;

@@ -1268,6 +1274,7 @@ EXPORT_SYMBOL_GPL(unix_destruct_fds);
static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
{
        int i;
+       int rc = 0;
        /*
         * Need to duplicate file references for the sake of garbage
@@ -1278,10 +1285,13 @@ static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
        if (!UNIXCB(skb).fp)
                return -ENOMEM;

-       for (i=scm->fp->count-1; i>=0; i--)
-               unix_inflight(scm->fp->fp[i]);
+       for (i=scm->fp->count-1; i>=0; i--) {
+               rc = unix_inflight(scm->fp->fp[i]);
+               if (rc)
+                       break;
+       }
        skb->destructor = unix_destruct_fds;
-       return 0;
+       return rc;
}

/*
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index 5f96cea..4042e9a 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -124,21 +124,25 @@ static struct sock *unix_get_socket(struct file *filp)
  *     descriptor if it is for an AF_UNIX socket.
  */

-void unix_inflight(struct file *fp)
+int unix_inflight(struct file *fp)
{
+       int ret = 0;
        struct sock *s = unix_get_socket(fp);
        if(s) {
                struct unix_sock *u = unix_sk(s);
                spin_lock(&unix_gc_lock);
-               if (atomic_inc_return(&u->inflight) == 1) {
+               ret = atomic_inc_return(&u->inflight);
+               if (ret == 1) {

                        BUG_ON(!list_empty(&u->link));
                        list_add_tail(&u->link, &gc_inflight_list);
                } else {
                        BUG_ON(list_empty(&u->link));
                }
                atomic_inc(&unix_tot_inflight);
+               ret = ret > get_max_files();
                spin_unlock(&unix_gc_lock);
        }
+       return ret;
}
EXPORT_SYMBOL_GPL(unix_notinflight);

@@ -270,7 +274,7 @@ static void inc_inflight_move_tail(struct unix_sock *u)
                list_move_tail(&u->link, &gc_candidates);
}

-static bool gc_in_progress = false;
+bool gc_in_progress = false;

void wait_for_unix_gc(void)
{

ну и для параноиков sysctl -w fs.files-max=1000