From owner-dev-commits-src-branches@freebsd.org Tue Aug 31 19:09:46 2021 Return-Path: Delivered-To: dev-commits-src-branches@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 9AC2267355F; Tue, 31 Aug 2021 19:09:46 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4GzcFQ19xFz4scT; Tue, 31 Aug 2021 19:09:46 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id B97151748A; Tue, 31 Aug 2021 19:09:45 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 17VJ9jlb074200; Tue, 31 Aug 2021 19:09:45 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 17VJ9jT4074199; Tue, 31 Aug 2021 19:09:45 GMT (envelope-from git) Date: Tue, 31 Aug 2021 19:09:45 GMT Message-Id: <202108311909.17VJ9jT4074199@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: 17093b04c34e - stable/13 - arm64: fix a potential KVA leak in pmap_demote_l1() MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: 17093b04c34e50f2de649b64d95e96492639472e Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-branches@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commits to the stable branches of the FreeBSD src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 31 Aug 2021 19:09:46 -0000 The branch stable/13 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=17093b04c34e50f2de649b64d95e96492639472e commit 17093b04c34e50f2de649b64d95e96492639472e Author: Alan Cox AuthorDate: 2021-06-26 03:29:38 +0000 Commit: Mark Johnston CommitDate: 2021-08-31 19:09:23 +0000 arm64: fix a potential KVA leak in pmap_demote_l1() In the unlikely event that the 1 GB page mapping being demoted is used to access the L1 page table page containing the 1 GB page mapping and the vm_page_alloc() to allocate a new L2 page table page fails, we would leak a page of kernel virtual address space. Fix this leak. (cherry picked from commit 5dd84e315a9f777772017f9f628aa67f08a6493a) --- sys/arm64/arm64/pmap.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/sys/arm64/arm64/pmap.c b/sys/arm64/arm64/pmap.c index 0220c0e8710b..4a5dff98f308 100644 --- a/sys/arm64/arm64/pmap.c +++ b/sys/arm64/arm64/pmap.c @@ -6219,7 +6219,8 @@ pmap_demote_l1(pmap_t pmap, pt_entry_t *l1, vm_offset_t va) VM_ALLOC_NOOBJ | VM_ALLOC_WIRED)) == NULL) { CTR2(KTR_PMAP, "pmap_demote_l1: failure for va %#lx" " in pmap %p", va, pmap); - return (NULL); + l2 = NULL; + goto fail; } l2phys = VM_PAGE_TO_PHYS(ml2); @@ -6248,6 +6249,7 @@ pmap_demote_l1(pmap_t pmap, pt_entry_t *l1, vm_offset_t va) pmap_update_entry(pmap, l1, l2phys | L1_TABLE, va, PAGE_SIZE); +fail: if (tmpl1 != 0) { pmap_kremove(tmpl1); kva_free(tmpl1, PAGE_SIZE);