Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Pavel Skripkin <paskripkin@gmail.com>
To:     jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us,
        davem@davemloft.net
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Pavel Skripkin <paskripkin@gmail.com>,
        syzbot+1071ad60cd7df39fdadb@syzkaller.appspotmail.com
Subject: [PATCH] net: sched: fix warning in tcindex_alloc_perfect_hash
Date:   Fri, 25 Jun 2021 23:23:48 +0300
Message-Id: <20210625202348.24560-1-paskripkin@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Syzbot reported warning in tcindex_alloc_perfect_hash. The problem
was in too big cp->hash, which triggers warning in kmalloc. Since
cp->hash comes from userspace, there is no need to warn if value
is not correct

Fixes: b9a24bb76bf6 ("net_sched: properly handle failure case of tcf_exts_init()")
Reported-and-tested-by: syzbot+1071ad60cd7df39fdadb@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
---
 net/sched/cls_tcindex.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index c4007b9cd16d..5b274534264c 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -304,7 +304,7 @@ static int tcindex_alloc_perfect_hash(struct net *net, struct tcindex_data *cp)
 	int i, err = 0;
 
 	cp->perfect = kcalloc(cp->hash, sizeof(struct tcindex_filter_result),
-			      GFP_KERNEL);
+			      GFP_KERNEL | __GFP_NOWARN);
 	if (!cp->perfect)
 		return -ENOMEM;
 
-- 
2.32.0