From patchwork Tue Apr 12 10:56:53 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Duoming Zhou X-Patchwork-Id: 12810626 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 3688BC4332F for ; Tue, 12 Apr 2022 12:00:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344538AbiDLMCT (ORCPT ); Tue, 12 Apr 2022 08:02:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42982 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244281AbiDLMCK (ORCPT ); Tue, 12 Apr 2022 08:02:10 -0400 Received: from zju.edu.cn (spam.zju.edu.cn [61.164.42.155]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id B43EE673DD; Tue, 12 Apr 2022 03:57:10 -0700 (PDT) Received: from ubuntu.localdomain (unknown [10.15.192.164]) by mail-app2 (Coremail) with SMTP id by_KCgBn3hX1WlVixrabAQ--.10506S4; Tue, 12 Apr 2022 18:57:03 +0800 (CST) From: Duoming Zhou To: krzk@kernel.org, linux-kernel@vger.kernel.org Cc: davem@davemloft.net, gregkh@linuxfoundation.org, alexander.deucher@amd.com, broonie@kernel.org, akpm@linux-foundation.org, netdev@vger.kernel.org, pabeni@redhat.com, Duoming Zhou Subject: [PATCH 2/2] drivers: nfc: nfcmrvl: fix double free bug in nfc_fw_download_done() Date: Tue, 12 Apr 2022 18:56:53 +0800 Message-Id: X-Mailer: git-send-email 2.17.1 In-Reply-To: References: In-Reply-To: References: X-CM-TRANSID: by_KCgBn3hX1WlVixrabAQ--.10506S4 X-Coremail-Antispam: 1UD129KBjvJXoW7Cw1DZFW8KF4ktF15tr43Jrb_yoW8CFyDpr WrGFy7Ar4DJr4YvFWFqFyDWrs8Cw47CryUGFZrG3yfZFn8tFyqyr1kGa4rZF4DWr48ta15 K39xJayUKanYvrJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvl1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s1l1IIY67AE w4v_Jr0_Jr4l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2 IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2 z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcV Aq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j 6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64 vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2IY04v7MxAIw28I cxkI7VAKI48JMxAIw28IcVCjz48v1sIEY20_GFWkJr1UJwCFx2IqxVCFs4IE7xkEbVWUJV W8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF 1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6x IIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvE x4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvj DU0xZFpf9x0JUdHUDUUUUU= X-CM-SenderInfo: qssqjiasttq6lmxovvfxof0/1tbiAgwSAVZdtZJwywAHsN Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org There are potential double free bug in nfc_fw_download_done(). The timer handler fw_dnld_timeout() and work item fw_dnld_rx_work() could both reach in fw_dnld_over() and nfc_fw_download_done() is not protected by any lock, which leads to double free. The race between fw_dnld_rx_work() and fw_dnld_timeout() can be shown as below: (Thread 1) | (Thread 2) fw_dnld_timeout | fw_dnld_rx_work | fw_dnld_over fw_dnld_over | nfc_fw_download_done nfc_fw_download_done | nfc_genl_fw_download_done nfc_genl_fw_download_done| nlmsg_free(msg) //(1) nlmsg_free(msg) //(2) | ... ... | The nlmsg_free() will deallocate sk_buff in position (1), but nlmsg_free will be deallocated again in position (2), which leads to double free. This patch adds spin_lock_irq() and check in fw_dnld_over() in order to synchronize among different threads that call fw_dnld_over(). So the double free bug could be prevented. Fixes: 3194c6870158e3 ("NFC: nfcmrvl: add firmware download support") Signed-off-by: Duoming Zhou Reviewed-by: Lin Ma Reported-by: kernel test robot Reported-by: kernel test robot --- drivers/nfc/nfcmrvl/fw_dnld.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/nfc/nfcmrvl/fw_dnld.c b/drivers/nfc/nfcmrvl/fw_dnld.c index c22a4556db5..7586a2f678d 100644 --- a/drivers/nfc/nfcmrvl/fw_dnld.c +++ b/drivers/nfc/nfcmrvl/fw_dnld.c @@ -116,7 +116,10 @@ static void fw_dnld_over(struct nfcmrvl_private *priv, u32 error) nfcmrvl_chip_halt(priv); } - nfc_fw_download_done(priv->ndev->nfc_dev, priv->fw_dnld.name, error); + spin_lock_irq(&priv->fw_dnld.lock); + if (dev->fw_download_in_progress) + nfc_fw_download_done(priv->ndev->nfc_dev, priv->fw_dnld.name, error); + spin_unlock_irq(&priv->fw_dnld.lock); } static void fw_dnld_timeout(struct timer_list *t)