--- zzzz-none-000/linux-2.6.28.10/mm/slab.c	2009-05-02 18:54:43.000000000 +0000
+++ puma5-6360-529/linux-2.6.28.10/mm/slab.c	2010-06-29 10:08:17.000000000 +0000
@@ -2865,6 +2865,13 @@
 
 	printk(KERN_ERR "%p: redzone 1:0x%llx, redzone 2:0x%llx.\n",
 			obj, redzone1, redzone2);
+	if (cache->flags & SLAB_STORE_USER) {
+		printk(KERN_ERR "Last user: [<%p>]",
+			*dbg_userword(cache, obj));
+		print_symbol("(%s)",
+				(unsigned long)*dbg_userword(cache, obj));
+		printk("\n");
+	}
 }
 
 static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
@@ -3081,7 +3088,7 @@
 		*dbg_redzone1(cachep, objp) = RED_ACTIVE;
 		*dbg_redzone2(cachep, objp) = RED_ACTIVE;
 	}
-#ifdef CONFIG_DEBUG_SLAB_LEAK
+#if defined(CONFIG_DEBUG_SLAB_LEAK) || defined(CONFIG_NET_DEBUG_SKBUFF_LEAK)
 	{
 		struct slab *slabp;
 		unsigned objnr;
@@ -3103,8 +3110,26 @@
 	return objp;
 }
 #else
+#if defined(CONFIG_NET_DEBUG_SKBUFF_LEAK)
+static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
+				gfp_t flags, void *objp, void *caller)
+{
+	if (!objp)
+		return objp;
+	{
+		struct slab *slabp;
+		unsigned objnr;
+
+		slabp = page_get_slab(virt_to_head_page(objp));
+		objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size;
+		slab_bufctl(slabp)[objnr] = BUFCTL_ACTIVE;
+	}
+	return objp;
+}
+#else
 #define cache_alloc_debugcheck_after(a,b,objp,d) (objp)
 #endif
+#endif
 
 #ifdef CONFIG_FAILSLAB
 
@@ -4329,12 +4354,22 @@
 	.release	= seq_release,
 };
 
-#ifdef CONFIG_DEBUG_SLAB_LEAK
+#if defined(CONFIG_DEBUG_SLAB_LEAK) || defined(CONFIG_NET_DEBUG_SKBUFF_LEAK)
 
-static void *leaks_start(struct seq_file *m, loff_t *pos)
+static void show_symbol(struct seq_file *m, unsigned long address)
 {
-	mutex_lock(&cache_chain_mutex);
-	return seq_list_start(&cache_chain, *pos);
+#ifdef CONFIG_KALLSYMS
+	unsigned long offset, size;
+	char modname[MODULE_NAME_LEN], name[KSYM_NAME_LEN];
+
+	if (lookup_symbol_attrs(address, &size, &offset, modname, name) == 0) {
+		seq_printf(m, "%s+%#lx/%#lx", name, offset, size);
+		if (modname[0])
+			seq_printf(m, " [%s]", modname);
+		return;
+	}
+#endif
+	seq_printf(m, "%p", (void *)address);
 }
 
 static inline int add_caller(unsigned long *n, unsigned long v)
@@ -4367,6 +4402,17 @@
 	return 1;
 }
 
+
+#endif
+
+#ifdef CONFIG_DEBUG_SLAB_LEAK
+
+static void *leaks_start(struct seq_file *m, loff_t *pos)
+{
+	mutex_lock(&cache_chain_mutex);
+	return seq_list_start(&cache_chain, *pos);
+}
+
 static void handle_slab(unsigned long *n, struct kmem_cache *c, struct slab *s)
 {
 	void *p;
@@ -4381,22 +4427,6 @@
 	}
 }
 
-static void show_symbol(struct seq_file *m, unsigned long address)
-{
-#ifdef CONFIG_KALLSYMS
-	unsigned long offset, size;
-	char modname[MODULE_NAME_LEN], name[KSYM_NAME_LEN];
-
-	if (lookup_symbol_attrs(address, &size, &offset, modname, name) == 0) {
-		seq_printf(m, "%s+%#lx/%#lx", name, offset, size);
-		if (modname[0])
-			seq_printf(m, " [%s]", modname);
-		return;
-	}
-#endif
-	seq_printf(m, "%p", (void *)address);
-}
-
 static int leaks_show(struct seq_file *m, void *p)
 {
 	struct kmem_cache *cachep = list_entry(p, struct kmem_cache, next);
@@ -4489,12 +4519,130 @@
 };
 #endif
 
+#ifdef CONFIG_NET_DEBUG_SKBUFF_LEAK
+
+#include <linux/skbuff.h>
+
+static void *skbuff_leaks_start(struct seq_file *m, loff_t *pos)
+{
+	mutex_lock(&cache_chain_mutex);
+	return seq_list_start(&cache_chain, *pos);
+}
+
+static void skbuff_handle_slab(unsigned long *n, struct kmem_cache *c, struct slab *s)
+{
+	void *p;
+	int i;
+	if (n[0] == n[1])
+		return;
+	for (i = 0, p = s->s_mem; i < c->num; i++, p += c->buffer_size) {
+		struct sk_buff *skb;
+		if (slab_bufctl(s)[i] != BUFCTL_ACTIVE)
+		    continue;
+		skb = (struct sk_buff *)p;
+		if (!add_caller(n, (unsigned long)skb->last_user))
+			return;
+	}
+}
+
+static int skbuff_leaks_show(struct seq_file *m, void *p)
+{
+	struct kmem_cache *cachep = list_entry(p, struct kmem_cache, next);
+	struct slab *slabp;
+	struct kmem_list3 *l3;
+	const char *name;
+	unsigned long *n = m->private;
+	int node;
+	int i;
+
+	if (strncmp(cachep->name, "skbuff_", 7) != 0)
+		return 0;
+
+	/* OK, we can do it */
+	n[1] = 0;
+
+	for_each_online_node(node) {
+		l3 = cachep->nodelists[node];
+		if (!l3)
+			continue;
+
+		check_irq_on();
+		spin_lock_irq(&l3->list_lock);
+
+		list_for_each_entry(slabp, &l3->slabs_full, list)
+			skbuff_handle_slab(n, cachep, slabp);
+		list_for_each_entry(slabp, &l3->slabs_partial, list)
+			skbuff_handle_slab(n, cachep, slabp);
+		spin_unlock_irq(&l3->list_lock);
+	}
+	name = cachep->name;
+	if (n[0] == n[1]) {
+		/* Increase the buffer size */
+		mutex_unlock(&cache_chain_mutex);
+		m->private = kzalloc(n[0] * 4 * sizeof(unsigned long), GFP_KERNEL);
+		if (!m->private) {
+			/* Too bad, we are really out */
+			m->private = n;
+			mutex_lock(&cache_chain_mutex);
+			return -ENOMEM;
+		}
+		*(unsigned long *)m->private = n[0] * 2;
+		kfree(n);
+		mutex_lock(&cache_chain_mutex);
+		/* Now make sure this entry will be retried */
+		m->count = m->size;
+		return 0;
+	}
+	for (i = 0; i < n[1]; i++) {
+		seq_printf(m, "%s: %lu ", name, n[2*i+3]);
+		show_symbol(m, n[2*i+2]);
+		seq_putc(m, '\n');
+	}
+
+	return 0;
+}
+
+static const struct seq_operations skbuffstats_op = {
+	.start = skbuff_leaks_start,
+	.next = s_next,
+	.stop = s_stop,
+	.show = skbuff_leaks_show,
+};
+
+static int skbuffstats_open(struct inode *inode, struct file *file)
+{
+	unsigned long *n = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	int ret = -ENOMEM;
+	if (n) {
+		ret = seq_open(file, &skbuffstats_op);
+		if (!ret) {
+			struct seq_file *m = file->private_data;
+			*n = PAGE_SIZE / (2 * sizeof(unsigned long));
+			m->private = n;
+			n = NULL;
+		}
+		kfree(n);
+	}
+	return ret;
+}
+
+static const struct file_operations proc_skbuffstats_operations = {
+	.open		= skbuffstats_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release_private,
+};
+#endif /* CONFIG_NET_DEBUG_SKBUFF_LEAK */
+
 static int __init slab_proc_init(void)
 {
 	proc_create("slabinfo",S_IWUSR|S_IRUGO,NULL,&proc_slabinfo_operations);
 #ifdef CONFIG_DEBUG_SLAB_LEAK
 	proc_create("slab_allocators", 0, NULL, &proc_slabstats_operations);
 #endif
+#ifdef CONFIG_NET_DEBUG_SKBUFF_LEAK
+	proc_create("skbuff_last_user", 0, NULL, &proc_skbuffstats_operations);
+#endif
 	return 0;
 }
 module_init(slab_proc_init);