[NETFILTER]: Fix OOPSes on machines with discontiguous cpu numbering.

Original patch by Harald Welte, with feedback from Herbert Xu
and testing by Sébastien Bernard.

EBTABLES, ARP tables, and IP/IP6 tables all assume that cpus
are numbered linearly.  That is not necessarily true.

This patch fixes that up by calculating the largest possible
cpu number, and allocating enough per-cpu structure space given
that.

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

1 files changed, 17 insertions, 10 deletions

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index c454014..f8ffbf6 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -26,6 +26,7 @@
 #include <linux/spinlock.h>
 #include <asm/uaccess.h>
 #include <linux/smp.h>
+#include <linux/cpumask.h>
 #include <net/sock.h>
 /* needed for logical [in,out]-dev filtering */
 #include "../br_private.h"
@@ -823,10 +824,11 @@ static int translate_table(struct ebt_replace *repl,
 		/* this will get free'd in do_replace()/ebt_register_table()
 		   if an error occurs */
 		newinfo->chainstack = (struct ebt_chainstack **)
-		   vmalloc(num_possible_cpus() * sizeof(struct ebt_chainstack));
+		   vmalloc((highest_possible_processor_id()+1) 
+				   		* sizeof(struct ebt_chainstack));
 		if (!newinfo->chainstack)
 			return -ENOMEM;
-		for (i = 0; i < num_possible_cpus(); i++) {
+		for_each_cpu(i) {
 			newinfo->chainstack[i] =
 			   vmalloc(udc_cnt * sizeof(struct ebt_chainstack));
 			if (!newinfo->chainstack[i]) {
@@ -895,9 +897,12 @@ static void get_counters(struct ebt_counter *oldcounters,
 
 	/* counters of cpu 0 */
 	memcpy(counters, oldcounters,
-	   sizeof(struct ebt_counter) * nentries);
+	       sizeof(struct ebt_counter) * nentries);
+
 	/* add other counters to those of cpu 0 */
-	for (cpu = 1; cpu < num_possible_cpus(); cpu++) {
+	for_each_cpu(cpu) {
+		if (cpu == 0)
+			continue;
 		counter_base = COUNTER_BASE(oldcounters, nentries, cpu);
 		for (i = 0; i < nentries; i++) {
 			counters[i].pcnt += counter_base[i].pcnt;
@@ -929,7 +934,8 @@ static int do_replace(void __user *user, unsigned int len)
 		BUGPRINT("Entries_size never zero\n");
 		return -EINVAL;
 	}
-	countersize = COUNTER_OFFSET(tmp.nentries) * num_possible_cpus();
+	countersize = COUNTER_OFFSET(tmp.nentries) * 
+					(highest_possible_processor_id()+1);
 	newinfo = (struct ebt_table_info *)
 	   vmalloc(sizeof(struct ebt_table_info) + countersize);
 	if (!newinfo)
@@ -1022,7 +1028,7 @@ static int do_replace(void __user *user, unsigned int len)
 
 	vfree(table->entries);
 	if (table->chainstack) {
-		for (i = 0; i < num_possible_cpus(); i++)
+		for_each_cpu(i)
 			vfree(table->chainstack[i]);
 		vfree(table->chainstack);
 	}
@@ -1040,7 +1046,7 @@ free_counterstmp:
 	vfree(counterstmp);
 	/* can be initialized in translate_table() */
 	if (newinfo->chainstack) {
-		for (i = 0; i < num_possible_cpus(); i++)
+		for_each_cpu(i)
 			vfree(newinfo->chainstack[i]);
 		vfree(newinfo->chainstack);
 	}
@@ -1132,7 +1138,8 @@ int ebt_register_table(struct ebt_table *table)
 		return -EINVAL;
 	}
 
-	countersize = COUNTER_OFFSET(table->table->nentries) * num_possible_cpus();
+	countersize = COUNTER_OFFSET(table->table->nentries) *
+					(highest_possible_processor_id()+1);
 	newinfo = (struct ebt_table_info *)
 	   vmalloc(sizeof(struct ebt_table_info) + countersize);
 	ret = -ENOMEM;
@@ -1186,7 +1193,7 @@ free_unlock:
 	up(&ebt_mutex);
 free_chainstack:
 	if (newinfo->chainstack) {
-		for (i = 0; i < num_possible_cpus(); i++)
+		for_each_cpu(i)
 			vfree(newinfo->chainstack[i]);
 		vfree(newinfo->chainstack);
 	}
@@ -1209,7 +1216,7 @@ void ebt_unregister_table(struct ebt_table *table)
 	up(&ebt_mutex);
 	vfree(table->private->entries);
 	if (table->private->chainstack) {
-		for (i = 0; i < num_possible_cpus(); i++)
+		for_each_cpu(i)
 			vfree(table->private->chainstack[i]);
 		vfree(table->private->chainstack);
 	}