From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: [PATCH 09/18] netfilter: x_tables: check for size overflow Date: Tue, 15 Mar 2016 02:27:53 +0100 Message-ID: <1458005282-24665-10-git-send-email-pablo@netfilter.org> References: <1458005282-24665-1-git-send-email-pablo@netfilter.org> Cc: davem@davemloft.net, netdev@vger.kernel.org To: netfilter-devel@vger.kernel.org Return-path: In-Reply-To: <1458005282-24665-1-git-send-email-pablo@netfilter.org> Sender: netfilter-devel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Florian Westphal Ben Hawkes says: integer overflow in xt_alloc_table_info, which on 32-bit systems can lead to small structure allocation and a copy_from_user based heap corruption. Reported-by: Ben Hawkes Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- 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 d0cd2b9..582c9cf 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -659,6 +659,9 @@ struct xt_table_info *xt_alloc_table_info(unsigned int size) struct xt_table_info *info = NULL; size_t sz = sizeof(*info) + size; + if (sz < sizeof(*info)) + return NULL; + /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */ if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages) return NULL; -- 2.1.4