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 338D0C433DF for ; Mon, 1 Jun 2020 18:59:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 10762207DA for ; Mon, 1 Jun 2020 18:59:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591037991; bh=Tny3VTVURpEgeM+9w0M0n1RNAkfCIp6+8DfMnH6Z1FY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UccMuOxzTbV3DSYK+95xgKE2hW3MWPM9xaA5FfFoqMY7cKIgiofj8WtZ8jc4yY9LZ 7P7x99tAiOdmfYhnYMEvzM+Tciyl1FeVSc+vLABhZig5NbSNpP2MfyWlMF8Ua4YCGC CACsUAe1r23Crs39a4wlCWukVCykMW43dAB7T09Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728796AbgFAR47 (ORCPT ); Mon, 1 Jun 2020 13:56:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:37876 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728791AbgFAR46 (ORCPT ); Mon, 1 Jun 2020 13:56:58 -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 0D84F207DA; Mon, 1 Jun 2020 17:56:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591034218; bh=Tny3VTVURpEgeM+9w0M0n1RNAkfCIp6+8DfMnH6Z1FY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HUljWw7akgkmxwALXjPSpy9WoN0pLTj9l7TCww2O7ufO3VR5wOQphLWDVaFU9jcFc YLfYeSUZ5cFimVCfTZXHrl3LwbbNkgp88a+6jUFtfwf3VZN/gIyRTVLhspgZicREIu Z06X5xN1Zl/5rzjuDVM7QQV6xY72v2T4hoTMIeOo= 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 4.4 45/48] mm/vmalloc.c: dont dereference possible NULL pointer in __vunmap() Date: Mon, 1 Jun 2020 19:53:55 +0200 Message-Id: <20200601174004.957880557@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200601173952.175939894@linuxfoundation.org> References: <20200601173952.175939894@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 @@ -1464,7 +1464,7 @@ 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);