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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 696C1C6FA82 for ; Tue, 13 Sep 2022 15:21:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236097AbiIMPVW (ORCPT ); Tue, 13 Sep 2022 11:21:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235782AbiIMPTW (ORCPT ); Tue, 13 Sep 2022 11:19:22 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33E337AC37; Tue, 13 Sep 2022 07:36:08 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 5DA43B80F9D; Tue, 13 Sep 2022 14:34:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A263FC433C1; Tue, 13 Sep 2022 14:34:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1663079661; bh=fl+1UOIJlFEE2wyNt2W4lBZHymVKH/kugNQe66C4Z6U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qw0qJYEyS/kEYm8morrU2ImrdBBQJeOI4dcoigJHY3AIN3ysKukEg0QjJG+V+WWb3 Z3eHrYpAyNAcOb5CQ/hVg/LKQwM+WiqR4k8GkYpvp+B23I1v9D/XgXJcx4f31e5gID Ss+9f+m4hKSKyOS4xEv1ZpN7rNZ8lvbHFNl4L3hM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Duoming Zhou , "David S. Miller" , Sasha Levin Subject: [PATCH 4.14 07/61] ethernet: rocker: fix sleep in atomic context bug in neigh_timer_handler Date: Tue, 13 Sep 2022 16:07:09 +0200 Message-Id: <20220913140346.835357179@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220913140346.422813036@linuxfoundation.org> References: <20220913140346.422813036@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Duoming Zhou [ Upstream commit c0955bf957be4bead01fae1d791476260da7325d ] The function neigh_timer_handler() is a timer handler that runs in an atomic context. When used by rocker, neigh_timer_handler() calls "kzalloc(.., GFP_KERNEL)" that may sleep. As a result, the sleep in atomic context bug will happen. One of the processes is shown below: ofdpa_fib4_add() ... neigh_add_timer() (wait a timer) neigh_timer_handler() neigh_release() neigh_destroy() rocker_port_neigh_destroy() rocker_world_port_neigh_destroy() ofdpa_port_neigh_destroy() ofdpa_port_ipv4_neigh() kzalloc(sizeof(.., GFP_KERNEL) //may sleep This patch changes the gfp_t parameter of kzalloc() from GFP_KERNEL to GFP_ATOMIC in order to mitigate the bug. Fixes: 00fc0c51e35b ("rocker: Change world_ops API and implementation to be switchdev independant") Signed-off-by: Duoming Zhou Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/rocker/rocker_ofdpa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/rocker/rocker_ofdpa.c b/drivers/net/ethernet/rocker/rocker_ofdpa.c index 0653b70723a34..5dad40257e12e 100644 --- a/drivers/net/ethernet/rocker/rocker_ofdpa.c +++ b/drivers/net/ethernet/rocker/rocker_ofdpa.c @@ -1277,7 +1277,7 @@ static int ofdpa_port_ipv4_neigh(struct ofdpa_port *ofdpa_port, bool removing; int err = 0; - entry = kzalloc(sizeof(*entry), GFP_KERNEL); + entry = kzalloc(sizeof(*entry), GFP_ATOMIC); if (!entry) return -ENOMEM; -- 2.35.1