From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D7A5D19BCD for ; Wed, 7 Jun 2023 20:35:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50959C433EF; Wed, 7 Jun 2023 20:35:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1686170122; bh=a89S2RHs75bjz/PqFiImDOIrIL5j3o7AOXMwYacPgtE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DXjjZVJna4zFu166WQ3jaAIfGIXsGogmgzzg5CaXzH+QmaCVj4lQewau1jfl32sKQ j7wVnOjmAj1gvu+NTCQOkx3sYMOdscrCuLYdFQ55Q39bVe4OflWBWJvRUTh6+aaFII 6zOwFqo04CqojHCqahFREdgLNdDcWPO5o1hW+LS8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hangyu Hua , Simon Horman , Pieter Jansen van Vuuren , Paolo Abeni , Sasha Levin Subject: [PATCH 4.19 26/88] net/sched: flower: fix possible OOB write in fl_set_geneve_opt() Date: Wed, 7 Jun 2023 22:15:43 +0200 Message-ID: <20230607200859.913940786@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230607200854.030202132@linuxfoundation.org> References: <20230607200854.030202132@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Hangyu Hua [ Upstream commit 4d56304e5827c8cc8cc18c75343d283af7c4825c ] If we send two TCA_FLOWER_KEY_ENC_OPTS_GENEVE packets and their total size is 252 bytes(key->enc_opts.len = 252) then key->enc_opts.len = opt->length = data_len / 4 = 0 when the third TCA_FLOWER_KEY_ENC_OPTS_GENEVE packet enters fl_set_geneve_opt. This bypasses the next bounds check and results in an out-of-bounds. Fixes: 0a6e77784f49 ("net/sched: allow flower to match tunnel options") Signed-off-by: Hangyu Hua Reviewed-by: Simon Horman Reviewed-by: Pieter Jansen van Vuuren Link: https://lore.kernel.org/r/20230531102805.27090-1-hbh25y@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/sched/cls_flower.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index 6163648145c19..7ffa28a98d743 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -640,6 +640,9 @@ static int fl_set_geneve_opt(const struct nlattr *nla, struct fl_flow_key *key, if (option_len > sizeof(struct geneve_opt)) data_len = option_len - sizeof(struct geneve_opt); + if (key->enc_opts.len > FLOW_DIS_TUN_OPTS_MAX - 4) + return -ERANGE; + opt = (struct geneve_opt *)&key->enc_opts.data[key->enc_opts.len]; memset(opt, 0xff, option_len); opt->length = data_len / 4; -- 2.39.2