From patchwork Sat Aug 27 15:38:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Duoming Zhou X-Patchwork-Id: 12957041 X-Patchwork-Delegate: kuba@kernel.org 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 B2FD1C0502A for ; Sat, 27 Aug 2022 15:42:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233469AbiH0Pmu (ORCPT ); Sat, 27 Aug 2022 11:42:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230144AbiH0Pmt (ORCPT ); Sat, 27 Aug 2022 11:42:49 -0400 Received: from zg8tmja5ljk3lje4ms43mwaa.icoremail.net (zg8tmja5ljk3lje4ms43mwaa.icoremail.net [209.97.181.73]) by lindbergh.monkeyblade.net (Postfix) with SMTP id 7F3FF642CE; Sat, 27 Aug 2022 08:42:46 -0700 (PDT) Received: from ubuntu.localdomain (unknown [218.12.17.21]) by mail-app4 (Coremail) with SMTP id cS_KCgDnet1nOgpjW00nBA--.27577S2; Sat, 27 Aug 2022 23:38:23 +0800 (CST) From: Duoming Zhou To: netdev@vger.kernel.org Cc: jiri@resnulli.us, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, linux-kernel@vger.kernel.org, Duoming Zhou Subject: [PATCH net] ethernet: rocker: fix sleep in atomic context bug in neigh_timer_handler Date: Sat, 27 Aug 2022 23:38:15 +0800 Message-Id: <20220827153815.124475-1-duoming@zju.edu.cn> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: cS_KCgDnet1nOgpjW00nBA--.27577S2 X-Coremail-Antispam: 1UD129KBjvJXoW7KF47GF18tF43uFWrKryDKFg_yoW8XrWrpa yrWFyjqF1kKF90ga1DXanYvrWrZ3WUAF9rG3WI9w15Zws2qrWDAF9YkFyY9FW0yFy8ZF4Y 9F18Aw13AFnFy3JanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUym14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26F1j6w1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1l42xK82IYc2Ij64vI r41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8Gjc xK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0 cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE42xK8V AvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E 14v26r1j6r4UYxBIdaVFxhVjvjDU0xZFpf9x0JUdHUDUUUUU= X-CM-SenderInfo: qssqjiasttq6lmxovvfxof0/1tbiAgIPAVZdtbMKaAAFsk Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org 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 --- 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 bc70c6abd6a..58cf7cc54f4 100644 --- a/drivers/net/ethernet/rocker/rocker_ofdpa.c +++ b/drivers/net/ethernet/rocker/rocker_ofdpa.c @@ -1273,7 +1273,7 @@ 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;