From 31018830a260ab4623413644a63be8af54dc816a Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 27 Feb 2018 19:42:32 +0100
Subject: [PATCH 06/19] netfilter: x_tables: limit allocation requests for blob
rule heads
Git-commit: 9d5c12a7c08f67999772065afd50fb222072114e
Patch-mainline: v4.17-rc1
References: git-fixes
This is a very conservative limit (134217728 rules), but good
enough to not trigger frequent oom from syzkaller.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Denis Kirjanov <dkirjanov@suse.com>
---
net/netfilter/x_tables.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 6804253c94e3..5cb719a877cd 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -777,6 +777,9 @@ EXPORT_SYMBOL(xt_check_entry_offsets);
*/
unsigned int *xt_alloc_entry_offsets(unsigned int size)
{
+ if (size > XT_MAX_TABLE_SIZE / sizeof(unsigned int))
+ return NULL;
+
return kvmalloc_array(size, sizeof(unsigned int), GFP_KERNEL | __GFP_ZERO);
}
--
2.16.4