From patchwork Thu May 14 00:50:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 11547601 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 915CD618 for ; Thu, 14 May 2020 00:50:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 718012065C for ; Thu, 14 May 2020 00:50:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="cICuSj3G" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 718012065C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5DD5280040; Wed, 13 May 2020 20:50:47 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 58D3D8003E; Wed, 13 May 2020 20:50:47 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4CA3280040; Wed, 13 May 2020 20:50:47 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0193.hostedemail.com [216.40.44.193]) by kanga.kvack.org (Postfix) with ESMTP id 308858003E for ; Wed, 13 May 2020 20:50:47 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id E1609181AEF0B for ; Thu, 14 May 2020 00:50:46 +0000 (UTC) X-FDA: 76813494492.06.gate86_40ff4d1ee0809 X-Spam-Summary: 2,0,0,98f6c303f82ee0f1,d41d8cd98f00b204,akpm@linux-foundation.org,,RULES_HIT:41:355:379:800:960:967:973:988:989:1260:1263:1345:1359:1381:1431:1437:1534:1541:1711:1730:1747:1777:1792:2198:2199:2393:2525:2553:2559:2563:2682:2685:2693:2859:2902:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3352:3865:3866:3867:3868:3870:3871:3872:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4321:5007:6261:6653:6737:7576:7904:8599:8660:8784:9025:9545:10004:10913:11026:11658:11914:12043:12048:12296:12297:12438:12517:12519:12555:12679:12783:12986:13069:13141:13148:13230:13311:13357:13846:14181:14384:14721:14849:21080:21220:21451:21627:21795:21939:21990:30003:30051:30054:30090,0,RBL:198.145.29.99:@linux-foundation.org:.lbl8.mailshell.net-62.2.0.100 64.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:16,LUA_SUMMARY:none X-HE-Tag: gate86_40ff4d1ee0809 X-Filterd-Recvd-Size: 3169 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf42.hostedemail.com (Postfix) with ESMTP for ; Thu, 14 May 2020 00:50:46 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 2899C20659; Thu, 14 May 2020 00:50:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589417446; bh=Tdtld1+Gnw5tiHHt44huteu6KhlPLFd73svzDCQU12s=; h=Date:From:To:Subject:In-Reply-To:From; b=cICuSj3G19aX3qajhRq+bh0umsFvSZtD7NnTYRXYd0B/EhUKHGip2mkNB5ZZvFw9Z ygX5B1GVQdFgYd4Dl/F93Its4qTyoGUHfe+4zn4JTBkqsLjf9ApBzE3Vixqwredem3 rDd6w43F+m6qfupoNg2F25VXj10+KIG/Vpcq5eZw= Date: Wed, 13 May 2020 17:50:44 -0700 From: Andrew Morton To: aarcange@redhat.com, akpm@linux-foundation.org, bgeffon@google.com, joel@joelfernandes.org, kirill.shutemov@linux.intel.com, linux-mm@kvack.org, lokeshgidra@google.com, minchan@kernel.org, mm-commits@vger.kernel.org, mst@redhat.com, sonnyrao@google.com, torvalds@linux-foundation.org, vbabka@suse.cz Subject: [patch 4/7] userfaultfd: fix remap event with MREMAP_DONTUNMAP Message-ID: <20200514005044.jvPMHXtzZ%akpm@linux-foundation.org> In-Reply-To: <20200513175005.1f4839360c18c0238df292d1@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Brian Geffon Subject: userfaultfd: fix remap event with MREMAP_DONTUNMAP A user is not required to set a new address when using MREMAP_DONTUNMAP as it can be used without MREMAP_FIXED. When doing so the remap event will use new_addr which may not have been set and we didn't propagate it back other then in the return value of remap_to. Because ret is always the new address it's probably more correct to use it rather than new_addr on the remap_event_complete call, and it resolves this bug. Link: http://lkml.kernel.org/r/20200506172158.218366-1-bgeffon@google.com Fixes: e346b3813067d4b ("mm/mremap: add MREMAP_DONTUNMAP to mremap()") Signed-off-by: Brian Geffon Cc: Lokesh Gidra Cc: Minchan Kim Cc: Kirill A. Shutemov Cc: Vlastimil Babka Cc: "Michael S . Tsirkin" Cc: Andrea Arcangeli Cc: Sonny Rao Cc: Joel Fernandes Signed-off-by: Andrew Morton --- mm/mremap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/mremap.c~userfaultfd-fix-remap-event-with-mremap_dontunmap +++ a/mm/mremap.c @@ -794,7 +794,7 @@ out: if (locked && new_len > old_len) mm_populate(new_addr + old_len, new_len - old_len); userfaultfd_unmap_complete(mm, &uf_unmap_early); - mremap_userfaultfd_complete(&uf, addr, new_addr, old_len); + mremap_userfaultfd_complete(&uf, addr, ret, old_len); userfaultfd_unmap_complete(mm, &uf_unmap); return ret; }