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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A27DC433DF for ; Mon, 1 Jun 2020 18:58:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 59BBE206C3 for ; Mon, 1 Jun 2020 18:58:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591037900; bh=2nbYkoHGHDeWm117cRo145SBRUcKKDtsBNqmmUFHlfo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=eu/6tuy6Im0n0+qW5lysR6FB9Zctq7H676wD7R05Q6cf8/EwT1oqjTAYWgcEVwd/0 uMc9NGxBFWqCYAO9MsiR5fCdGDm+cvyCFkqvhi84+JKLpVZW9BXss1CvmfgtM3uGnR 7qSGm6kvZa54JhXTguaAs/7s0BBx0jmT9HjiyBCs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728736AbgFAS6Q (ORCPT ); Mon, 1 Jun 2020 14:58:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:41766 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729325AbgFAR7U (ORCPT ); Mon, 1 Jun 2020 13:59:20 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CD2632076B; Mon, 1 Jun 2020 17:59:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591034360; bh=2nbYkoHGHDeWm117cRo145SBRUcKKDtsBNqmmUFHlfo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TcsUf/NRXjd+MevWhK9GquwmcTmELeaWSK2tO8ML2li3YHttggWfDHZe3+H20hg4T S897E3iA5nPeyLlTK55yTU5wI2FyPfAHHbILINWIinJnN8ZymAesuL/nk7Gop1in6O TZOFS4Njz0IsZgqAruQ5bHiLdYygcoyXRPYXvdsY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Liviu Dudau , Andrew Morton , Chintan Pandya , Andrey Ryabinin , Linus Torvalds , Guenter Roeck Subject: [PATCH 4.9 59/61] mm/vmalloc.c: dont dereference possible NULL pointer in __vunmap() Date: Mon, 1 Jun 2020 19:54:06 +0200 Message-Id: <20200601174022.410196971@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200601174010.316778377@linuxfoundation.org> References: <20200601174010.316778377@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Liviu Dudau commit 6ade20327dbb808882888ed8ccded71e93067cf9 upstream. find_vmap_area() can return a NULL pointer and we're going to dereference it without checking it first. Use the existing find_vm_area() function which does exactly what we want and checks for the NULL pointer. Link: http://lkml.kernel.org/r/20181228171009.22269-1-liviu@dudau.co.uk Fixes: f3c01d2f3ade ("mm: vmalloc: avoid racy handling of debugobjects in vunmap") Signed-off-by: Liviu Dudau Reviewed-by: Andrew Morton Cc: Chintan Pandya Cc: Andrey Ryabinin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- mm/vmalloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1499,7 +1499,7 @@ static void __vunmap(const void *addr, i addr)) return; - area = find_vmap_area((unsigned long)addr)->vm; + area = find_vm_area(addr); if (unlikely(!area)) { WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n", addr);