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 39263C433FE for ; Wed, 23 Nov 2022 09:07:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237072AbiKWJH3 (ORCPT ); Wed, 23 Nov 2022 04:07:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45350 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237172AbiKWJHD (ORCPT ); Wed, 23 Nov 2022 04:07:03 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F32D10611A for ; Wed, 23 Nov 2022 01:06:48 -0800 (PST) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 382C961B4D for ; Wed, 23 Nov 2022 09:06:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 290A4C433D6; Wed, 23 Nov 2022 09:06:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669194392; bh=6hxc6MPuHJj9vFFflZOhIMbK1Bnk4vLqq1DobuXLxT8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rtPi3RQS+8j3ZGfRbEddC9fFNO9mqnMnvQVRs4SnPKn8EHHIkWU95fdlTiOoC1dKb Ogu2nPqas+KfzMLniRXQam2rvBSuXljcwk9Pdz6CTX3ObImugRU5vHhPZipvLmrUxV aTltoLcJhKKCjtdBgl8z/25HKx35bsBhL6opIvRg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yang Yingliang , Damien Le Moal , Sasha Levin Subject: [PATCH 4.19 064/114] ata: libata-transport: fix double ata_host_put() in ata_tport_add() Date: Wed, 23 Nov 2022 09:50:51 +0100 Message-Id: <20221123084554.446886094@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123084551.864610302@linuxfoundation.org> References: <20221123084551.864610302@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: stable@vger.kernel.org From: Yang Yingliang [ Upstream commit 8c76310740807ade5ecdab5888f70ecb6d35732e ] In the error path in ata_tport_add(), when calling put_device(), ata_tport_release() is called, it will put the refcount of 'ap->host'. And then ata_host_put() is called again, the refcount is decreased to 0, ata_host_release() is called, all ports are freed and set to null. When unbinding the device after failure, ata_host_stop() is called to release the resources, it leads a null-ptr-deref(), because all the ports all freed and null. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 CPU: 7 PID: 18671 Comm: modprobe Kdump: loaded Tainted: G E 6.1.0-rc3+ #8 pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : ata_host_stop+0x3c/0x84 [libata] lr : release_nodes+0x64/0xd0 Call trace: ata_host_stop+0x3c/0x84 [libata] release_nodes+0x64/0xd0 devres_release_all+0xbc/0x1b0 device_unbind_cleanup+0x20/0x70 really_probe+0x158/0x320 __driver_probe_device+0x84/0x120 driver_probe_device+0x44/0x120 __driver_attach+0xb4/0x220 bus_for_each_dev+0x78/0xdc driver_attach+0x2c/0x40 bus_add_driver+0x184/0x240 driver_register+0x80/0x13c __pci_register_driver+0x4c/0x60 ahci_pci_driver_init+0x30/0x1000 [ahci] Fix this by removing redundant ata_host_put() in the error path. Fixes: 2623c7a5f279 ("libata: add refcounting to ata_host") Signed-off-by: Yang Yingliang Signed-off-by: Damien Le Moal Signed-off-by: Sasha Levin --- drivers/ata/libata-transport.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/ata/libata-transport.c b/drivers/ata/libata-transport.c index 43a91495ee67..f04f4f977400 100644 --- a/drivers/ata/libata-transport.c +++ b/drivers/ata/libata-transport.c @@ -317,7 +317,6 @@ int ata_tport_add(struct device *parent, tport_err: transport_destroy_device(dev); put_device(dev); - ata_host_put(ap->host); return error; } -- 2.35.1