From: Florian Westphal <fw@strlen.de>
To: netfilter-devel@vger.kernel.org
Cc: syzkaller-bugs@googlegroups.com, Florian Westphal <fw@strlen.de>,
syzbot+cf23983d697c26c34f60@syzkaller.appspotmail.com
Subject: [PATCH nf] netfilter: nft_osf: add missing check for DREG attribute
Date: Sat, 18 Jan 2020 11:27:25 +0100 [thread overview]
Message-ID: <20200118102725.30600-1-fw@strlen.de> (raw)
In-Reply-To: <000000000000d740e5059c65cbd0@google.com>
syzbot reports just another NULL deref crash because of missing test
for presence of the attribute.
Reported-by: syzbot+cf23983d697c26c34f60@syzkaller.appspotmail.com
Fixes: b96af92d6eaf9fadd ("netfilter: nf_tables: implement Passive OS fingerprint module in nft_osf")
Signed-off-by: Florian Westphal <fw@strlen.de>
---
net/netfilter/nft_osf.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
index f54d6ae15bb1..b42247aa48a9 100644
--- a/net/netfilter/nft_osf.c
+++ b/net/netfilter/nft_osf.c
@@ -61,6 +61,9 @@ static int nft_osf_init(const struct nft_ctx *ctx,
int err;
u8 ttl;
+ if (!tb[NFTA_OSF_DREG])
+ return -EINVAL;
+
if (tb[NFTA_OSF_TTL]) {
ttl = nla_get_u8(tb[NFTA_OSF_TTL]);
if (ttl > 2)
--
2.24.1
next prev parent reply other threads:[~2020-01-18 10:29 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-18 8:25 general protection fault in nft_parse_register syzbot
2020-01-18 10:27 ` Florian Westphal [this message]
2020-01-18 11:21 ` [PATCH nf] netfilter: nft_osf: add missing check for DREG attribute Fernando Fernández Mancera
2020-01-18 20:19 ` Pablo Neira Ayuso
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