[PATCH 11/30] netfilter: x_tables: cap allocations at 512 mbyte
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: 2018-03-12 17:59:36
Subsystem:
netfilter, networking [general], the rest · Maintainers:
Pablo Neira Ayuso, Florian Westphal, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Florian Westphal <fw@strlen.de> Arbitrary limit, however, this still allows huge rulesets (> 1 million rules). This helps with automated fuzzer as it prevents oom-killer invocation. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- net/netfilter/x_tables.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 4e6cbb38e616..dc68ac49614a 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c@@ -40,6 +40,7 @@ MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module"); #define XT_PCPU_BLOCK_SIZE 4096 +#define XT_MAX_TABLE_SIZE (512 * 1024 * 1024) struct compat_delta { unsigned int offset; /* offset in kernel */
@@ -1117,7 +1118,7 @@ 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)) + if (sz < sizeof(*info) || sz >= XT_MAX_TABLE_SIZE) return NULL; /* __GFP_NORETRY is not fully supported by kvmalloc but it should
--
2.11.0