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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 16B5FECE587 for ; Tue, 1 Oct 2019 16:41:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA1A8205C9 for ; Tue, 1 Oct 2019 16:41:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569948087; bh=vj/qwHHiJ4il+2uRSoB+681GnRxxk7xj4r+VUN9DvNo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BGDmL6o6ogKQ8fWzsTHzlADvMmtepvQQGRLu6VB5tBi2WsCfGLyYrcs/lVYyjdJ5J RghrCbDd6Asj63Bmee0S3OhVgj4gXfQUV98u8zFL89JBZnOYE5UYGukG7CUQxiEUPe GBNN1e5FVzI7iV1uqRPNHYmcOwtt3kfcLEpF52/A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730995AbfJAQlZ (ORCPT ); Tue, 1 Oct 2019 12:41:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:52880 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730896AbfJAQlV (ORCPT ); Tue, 1 Oct 2019 12:41:21 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4CB132168B; Tue, 1 Oct 2019 16:41:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569948081; bh=vj/qwHHiJ4il+2uRSoB+681GnRxxk7xj4r+VUN9DvNo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s4CRyY+6yAqwlsgF5b9vmNLjJITPk/nNyYvw41jzgyk4EX7cuF/HjMAhgWhsdhVGG a5iVE6nkwHPd3nyVHm+jsOQk0gnOejp6au95BZqWc3JQp5iWUg8fzfsxfihNoWLQjv ZuAl1w05dJ5dx1m58x9C2SV9+JH+ElUfyxVV4hf8= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , syzbot , Jakub Kicinski , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.3 70/71] sch_netem: fix a divide by zero in tabledist() Date: Tue, 1 Oct 2019 12:39:20 -0400 Message-Id: <20191001163922.14735-70-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191001163922.14735-1-sashal@kernel.org> References: <20191001163922.14735-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet [ Upstream commit b41d936b5ecfdb3a4abc525ce6402a6c49cffddc ] syzbot managed to crash the kernel in tabledist() loading an empty distribution table. t = dist->table[rnd % dist->size]; Simply return an error when such load is attempted. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/sch_netem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index b17f2ed970e29..f5cb35e550f8d 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -777,7 +777,7 @@ static int get_dist_table(struct Qdisc *sch, struct disttable **tbl, struct disttable *d; int i; - if (n > NETEM_DIST_MAX) + if (!n || n > NETEM_DIST_MAX) return -EINVAL; d = kvmalloc(sizeof(struct disttable) + n * sizeof(s16), GFP_KERNEL); -- 2.20.1