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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7B7B2C433EF for ; Fri, 12 Nov 2021 12:07:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6522D60F0F for ; Fri, 12 Nov 2021 12:07:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235078AbhKLMJu (ORCPT ); Fri, 12 Nov 2021 07:09:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36546 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234910AbhKLMJn (ORCPT ); Fri, 12 Nov 2021 07:09:43 -0500 Received: from mail-pf1-x430.google.com (mail-pf1-x430.google.com [IPv6:2607:f8b0:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B602BC061203; Fri, 12 Nov 2021 04:06:52 -0800 (PST) Received: by mail-pf1-x430.google.com with SMTP id c4so8345834pfj.2; Fri, 12 Nov 2021 04:06:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=MIyRtrqfmfv9Q70WA5OuleW3S97RwfmhJIbO/13nPI0=; b=eUrb7nENr9K/JwpH4dsIeY4/ml8fLrNKUXppJa64u3i+7roPNJxy6uMNnHS2YadqUZ yCPkY8CybmqjnJT6khQDAItloHqXM9bZZUIkOdyMYTXVK5m/36NwK9b+FLviishKTAIO YYkRqV+0h3lAmwuQgRtb+P4tkD3JnOCdy4yY9kZx/kG+Q3jVoPT/vSqlN7FP/5HtMBDQ bF/KmXFYQpClbh1z0IYOwhDQmY35nM+9i1KzpdMYL/6e4EjeOlfMYXpmeP+fqyejc+lE S7Gh16ymepXekxve8I7zwHXpMASvM5Ckjgc2m9yXaEGq8hN9bjmfWRmkFbDtISNIgNml s8+w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=MIyRtrqfmfv9Q70WA5OuleW3S97RwfmhJIbO/13nPI0=; b=QmMGqb8A9SKjJWwdxDPtH0oiTJpnWh1JdLs+jtnO8hSXAmAGAkAbKy2nwiSiFBO517 PJQjSMYHVeA0xWcth6ipXJPT/bb6o4LJJwgHwZTki3ko0g0o7ZqsV19UMyI8vkK5VGrL x8CigZ10grSNVZo5gL1V+bHbwa6v2aIjz8Wg3H4wCp+8ISa6RWVRJzr1djxrxYtHUtt5 YQT5ESMO72a61Is3DaAP1FC0yiAZXSpqM0/sUveyXrMkpVnltj6A/NZdHIOEt0ZamcyJ iMAqJNHxeIec1eJlfEY8+ikZlZTeRXQS18C91gOGvmcZ23yVFTRShvBKsmt99/KhUmIj ha8g== X-Gm-Message-State: AOAM532c9C+Yq+/oAhUWE7e6EX8cKe/TS7K7lhKIkdl77iAfm8QwYIGN ErrjYPRuhfUJkXfMwLPlBkdl+4L2prr3JDqfQcbSWQ== X-Google-Smtp-Source: ABdhPJx8ypXWbxfOJRQS60YeMql/1h8CczQ/+31wcaOfd4KGWHLiyyGTBRhCBrI4M6Pm9qh361QThQ== X-Received: by 2002:a63:5c13:: with SMTP id q19mr9459006pgb.350.1636718812226; Fri, 12 Nov 2021 04:06:52 -0800 (PST) Received: from fanta-arch.localdomain ([148.163.172.142]) by smtp.gmail.com with ESMTPSA id f15sm7058837pfe.171.2021.11.12.04.06.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 Nov 2021 04:06:51 -0800 (PST) From: Letu Ren To: skashyap@marvell.com, jhasan@marvell.com, jejb@linux.ibm.com, martin.petersen@oracle.com Cc: GR-QLogic-Storage-Upstream@marvell.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Letu Ren , Zheyu Ma , Wende Tan Subject: [PATCH] scsi: qedf: Fix a UAF bug in __qedf_probe Date: Fri, 12 Nov 2021 20:06:41 +0800 Message-Id: <20211112120641.16073-1-fantasquex@gmail.com> X-Mailer: git-send-email 2.33.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In __qedf_probe, if `qedf->cdev` is NULL which means qed_ops->common->probe() failed, then the program will goto label err1, scsi_host_put() will free `lport->host` pointer. Because the memory `qedf` points to is allocated by libfc_host_alloc(), it will be freed by scsi_host_put(). However, the if statement below label err0 only checks whether qedf is NULL but doesn't check whether the memory has been freed. So a UAF bug occurred. There are two ways to get to the statements below err0. the first one is described as before. `qedf` should be set to NULL. The second way is goto `err0` directly. In this way `qedf` hasn't been changed and it has the initial value `NULL`. So the program wont't go to the if statement in any situation. The KASAN logs are as follows: [ 2.312969] BUG: KASAN: use-after-free in __qedf_probe+0x5dcf/0x6bc0 [ 2.312969] [ 2.312969] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 2.312969] Call Trace: [ 2.312969] dump_stack_lvl+0x59/0x7b [ 2.312969] print_address_description+0x7c/0x3b0 [ 2.312969] ? __qedf_probe+0x5dcf/0x6bc0 [ 2.312969] __kasan_report+0x160/0x1c0 [ 2.312969] ? __qedf_probe+0x5dcf/0x6bc0 [ 2.312969] kasan_report+0x4b/0x70 [ 2.312969] ? kobject_put+0x25d/0x290 [ 2.312969] kasan_check_range+0x2ca/0x310 [ 2.312969] __qedf_probe+0x5dcf/0x6bc0 [ 2.312969] ? selinux_kernfs_init_security+0xdc/0x5f0 [ 2.312969] ? trace_rpm_return_int_rcuidle+0x18/0x120 [ 2.312969] ? rpm_resume+0xa5c/0x16e0 [ 2.312969] ? qedf_get_generic_tlv_data+0x160/0x160 [ 2.312969] local_pci_probe+0x13c/0x1f0 [ 2.312969] pci_device_probe+0x37e/0x6c0 Reported-by: Zheyu Ma Signed-off-by: Letu Ren Co-developed-by: Wende Tan Signed-off-by: Wende Tan --- drivers/scsi/qedf/qedf_main.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/drivers/scsi/qedf/qedf_main.c b/drivers/scsi/qedf/qedf_main.c index 42d0d941dba5..3ea552acd82a 100644 --- a/drivers/scsi/qedf/qedf_main.c +++ b/drivers/scsi/qedf/qedf_main.c @@ -3683,11 +3683,6 @@ static int __qedf_probe(struct pci_dev *pdev, int mode) err1: scsi_host_put(lport->host); err0: - if (qedf) { - QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_DISC, "Probe done.\n"); - - clear_bit(QEDF_PROBING, &qedf->flags); - } return rc; } -- 2.33.1