From 5bad87348c70bb4d36e876523aade31e9dedd2fc Mon Sep 17 00:00:00 2001 From: Marcelo Ricardo Leitner Date: Fri, 2 Dec 2016 07:46:38 -0200 Subject: [PATCH] netfilter: x_tables: avoid warn and OOM killer on vmalloc call Andrey Konovalov reported that this vmalloc call is based on an userspace request and that it's spewing traces, which may flood the logs and cause DoS if abused. Florian Westphal also mentioned that this call should not trigger OOM killer. This patch brings the vmalloc call in sync to kmalloc and disables the warn trace on allocation failure and also disable OOM killer invocation. Note, however, that under such stress situation, other places may trigger OOM killer invocation. Reported-by: Andrey Konovalov Cc: Florian Westphal Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: Pablo Neira Ayuso --- net/netfilter/x_tables.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index f6ce4a7036e6..2ff499680cc6 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -959,7 +959,9 @@ struct xt_table_info *xt_alloc_table_info(unsigned int size) if (sz <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) info = kmalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY); if (!info) { - info = vmalloc(sz); + info = __vmalloc(sz, GFP_KERNEL | __GFP_NOWARN | + __GFP_NORETRY | __GFP_HIGHMEM, + PAGE_KERNEL); if (!info) return NULL; } -- 2.20.1