[PATCH 5.14 171/172] netfilter: nf_tables: Fix oversized kvmalloc() calls

From: Greg Kroah-Hartman
Date: Mon Oct 04 2021 - 09:42:36 EST


From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>

commit 45928afe94a094bcda9af858b96673d59bc4a0e9 upstream.

The commit 7661809d493b ("mm: don't allow oversized kvmalloc() calls")
limits the max allocatable memory via kvmalloc() to MAX_INT.

Reported-by: syzbot+cd43695a64bcd21b8596@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netfilter/nf_tables_api.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4336,7 +4336,7 @@ static int nf_tables_newset(struct sk_bu
if (ops->privsize != NULL)
size = ops->privsize(nla, &desc);
alloc_size = sizeof(*set) + size + udlen;
- if (alloc_size < size)
+ if (alloc_size < size || alloc_size > INT_MAX)
return -ENOMEM;
set = kvzalloc(alloc_size, GFP_KERNEL);
if (!set)