From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E01BE22D280; Fri, 4 Oct 2024 18:31:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728066692; cv=none; b=cvmrATTMblRSULYkFlapGuNXVh/p9/H1Zzn8qGoNZ9DGpfnY25EXV1TlJCPfiGbb2krJkMplvnOOqFTZ7rzq8CZdGqIXsaqLff2elQYFFvhOg1xbt/+qEK0ASVP9CYs63YirZCko5gy4Ukovl1iaZOP8ROtJHGBRdlobyi2mbPY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728066692; c=relaxed/simple; bh=R+64p4hwRnDv9uSJCRD1eyJF5TnVQ5rxxFQxgICrCrg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=niHrppqnbqnMq2RF37sNNI7OQwE3ty4K6GxF7sYebslbxFq7m+/EIUIJDQ6fHOLKGHBusSoELrKF//8wUpurDylzP/lO2hfX78QkTohJC6f2+NIo5JZ6B6C3Q/ZC5ktTW39bTufj7YXJ/E9pcxfTgUwqwX+LwWDfAOjQ3MZvcpQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hI2OS9r7; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hI2OS9r7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4AAAAC4CECD; Fri, 4 Oct 2024 18:31:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728066691; bh=R+64p4hwRnDv9uSJCRD1eyJF5TnVQ5rxxFQxgICrCrg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hI2OS9r71XeP/BpeIjhoMJ1qI8IWJN2ufOyP02WUy7Z/DF1O0FqBNczBlN2zHV3QH zNgOdrnqc/8XQgfDq6eDQ+jyk5C/73HKMXEUHSxgiG353sms0lMtLrgGmsYyawB9k8 QKuFD23tlRfejp3YwcrI2yiaOQSTXAZR1tsBifM1oOojzXEc6IQV8OnZxDg+lZVsVW hlliaSB6exbViHxosJHL/j0uqDfcMr0ebdcukg3u5tKrubGJqGw5+BVcMjSNZJCo4l I18S6tGzj5uvbXnX90DqUZmxby3rPvJ2XgLQ/PrTU1aGyyXupVVEGN2XfxGj9KvUu0 9XA6PPIe3a49w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Kaixin Wang , Logan Gunthorpe , Jon Mason , Sasha Levin , kurt.schwemmer@microsemi.com, dave.jiang@intel.com, allenbh@gmail.com, linux-pci@vger.kernel.org, ntb@lists.linux.dev Subject: [PATCH AUTOSEL 5.4 14/21] ntb: ntb_hw_switchtec: Fix use after free vulnerability in switchtec_ntb_remove due to race condition Date: Fri, 4 Oct 2024 14:30:49 -0400 Message-ID: <20241004183105.3675901-14-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241004183105.3675901-1-sashal@kernel.org> References: <20241004183105.3675901-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.284 Content-Transfer-Encoding: 8bit From: Kaixin Wang [ Upstream commit e51aded92d42784313ba16c12f4f88cc4f973bbb ] In the switchtec_ntb_add function, it can call switchtec_ntb_init_sndev function, then &sndev->check_link_status_work is bound with check_link_status_work. switchtec_ntb_link_notification may be called to start the work. If we remove the module which will call switchtec_ntb_remove to make cleanup, it will free sndev through kfree(sndev), while the work mentioned above will be used. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | check_link_status_work switchtec_ntb_remove | kfree(sndev); | | if (sndev->link_force_down) | // use sndev Fix it by ensuring that the work is canceled before proceeding with the cleanup in switchtec_ntb_remove. Signed-off-by: Kaixin Wang Reviewed-by: Logan Gunthorpe Signed-off-by: Jon Mason Signed-off-by: Sasha Levin --- drivers/ntb/hw/mscc/ntb_hw_switchtec.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c index 86ffa716eaf22..db9be3ce1cd0d 100644 --- a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c +++ b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c @@ -1558,6 +1558,7 @@ static void switchtec_ntb_remove(struct device *dev, switchtec_ntb_deinit_db_msg_irq(sndev); switchtec_ntb_deinit_shared_mw(sndev); switchtec_ntb_deinit_crosslink(sndev); + cancel_work_sync(&sndev->check_link_status_work); kfree(sndev); dev_info(dev, "ntb device unregistered\n"); } -- 2.43.0