From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9910CC433EF for ; Tue, 5 Oct 2021 13:52:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80757604D1 for ; Tue, 5 Oct 2021 13:52:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236002AbhJENyE (ORCPT ); Tue, 5 Oct 2021 09:54:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:60480 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235480AbhJENxF (ORCPT ); Tue, 5 Oct 2021 09:53:05 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id AC62E61989; Tue, 5 Oct 2021 13:51:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1633441870; bh=OTrccWwKPffRiq3S6lIt8TgRqj+9/RN0ax0h0LgFrls=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oNKZ6yxRKPie7Fg07LuPpcALLxRuWgOw/vB2Vk1LIZ+u7r6cOw2JO8rItrzEaCYV2 qp4+y8BhqLblvcTHBNZ1KEenNN8lh1TNxIMlP3Rqhjzr2eb2KaEnm5mWYomhSNgX2X Kh4ZB3h78dE6P+45obM8QRiGBtCdKKd07F/vUtmeUL7RvxrBiZAYCt1jmGWh7eonw0 B/SMzjn2vHSn6vWfzDmTnw47nToECxtgUn/ZZjz6W+7cbJtU4eF2M4y9MZ7hzzIyvO koGfkWgDyeF0+ZEmptSTNA4MldcZi72yZj3icMhSZgHRNYH7A//hUQY6b3CDYAqkj/ yB1DlwdZVPHNw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?=E7=8E=8B=E8=B4=87?= , Abaci , "David S . Miller" , Sasha Levin , jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us, kuba@kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.14 25/40] net: prevent user from passing illegal stab size Date: Tue, 5 Oct 2021 09:50:04 -0400 Message-Id: <20211005135020.214291-25-sashal@kernel.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211005135020.214291-1-sashal@kernel.org> References: <20211005135020.214291-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: 王贇 [ Upstream commit b193e15ac69d56f35e1d8e2b5d16cbd47764d053 ] We observed below report when playing with netlink sock: UBSAN: shift-out-of-bounds in net/sched/sch_api.c:580:10 shift exponent 249 is too large for 32-bit type CPU: 0 PID: 685 Comm: a.out Not tainted Call Trace: dump_stack_lvl+0x8d/0xcf ubsan_epilogue+0xa/0x4e __ubsan_handle_shift_out_of_bounds+0x161/0x182 __qdisc_calculate_pkt_len+0xf0/0x190 __dev_queue_xmit+0x2ed/0x15b0 it seems like kernel won't check the stab log value passing from user, and will use the insane value later to calculate pkt_len. This patch just add a check on the size/cell_log to avoid insane calculation. Reported-by: Abaci Signed-off-by: Michael Wang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- include/net/pkt_sched.h | 1 + net/sched/sch_api.c | 6 ++++++ 2 files changed, 7 insertions(+) diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index 6d7b12cba015..bf79f3a890af 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -11,6 +11,7 @@ #include #define DEFAULT_TX_QUEUE_LEN 1000 +#define STAB_SIZE_LOG_MAX 30 struct qdisc_walker { int stop; diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index f87d07736a14..148edd0e71e3 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -513,6 +513,12 @@ static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt, return stab; } + if (s->size_log > STAB_SIZE_LOG_MAX || + s->cell_log > STAB_SIZE_LOG_MAX) { + NL_SET_ERR_MSG(extack, "Invalid logarithmic size of size table"); + return ERR_PTR(-EINVAL); + } + stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL); if (!stab) return ERR_PTR(-ENOMEM); -- 2.33.0