From owner-svn-src-all@freebsd.org Thu Jan 3 16:26:53 2019 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 8570F142F5C7; Thu, 3 Jan 2019 16:26:53 +0000 (UTC) (envelope-from markj@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) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 2A34583EF8; Thu, 3 Jan 2019 16:26:53 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 181C923B2E; Thu, 3 Jan 2019 16:26:53 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x03GQqGD043416; Thu, 3 Jan 2019 16:26:52 GMT (envelope-from markj@FreeBSD.org) Received: (from markj@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x03GQqiw043415; Thu, 3 Jan 2019 16:26:52 GMT (envelope-from markj@FreeBSD.org) Message-Id: <201901031626.x03GQqiw043415@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: markj set sender to markj@FreeBSD.org using -f From: Mark Johnston Date: Thu, 3 Jan 2019 16:26:52 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r342736 - head/sys/riscv/riscv X-SVN-Group: head X-SVN-Commit-Author: markj X-SVN-Commit-Paths: head/sys/riscv/riscv X-SVN-Commit-Revision: 342736 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 2A34583EF8 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.93 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.995,0]; NEURAL_HAM_LONG(-1.00)[-0.998,0]; NEURAL_HAM_SHORT(-0.94)[-0.939,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 03 Jan 2019 16:26:53 -0000 Author: markj Date: Thu Jan 3 16:26:52 2019 New Revision: 342736 URL: https://svnweb.freebsd.org/changeset/base/342736 Log: Fix a use-after-free in the riscv pmap_release() implementation. Don't bother zeroing the top-level page before freeing it. Previously, the page was freed before being zeroed. Reviewed by: jhb, kib MFC after: 1 week Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D18720 Modified: head/sys/riscv/riscv/pmap.c Modified: head/sys/riscv/riscv/pmap.c ============================================================================== --- head/sys/riscv/riscv/pmap.c Thu Jan 3 16:24:03 2019 (r342735) +++ head/sys/riscv/riscv/pmap.c Thu Jan 3 16:26:52 2019 (r342736) @@ -1297,17 +1297,13 @@ pmap_release(pmap_t pmap) ("pmap_release: pmap resident count %ld != 0", pmap->pm_stats.resident_count)); - m = PHYS_TO_VM_PAGE(DMAP_TO_PHYS((vm_offset_t)pmap->pm_l1)); - vm_page_unwire_noq(m); - vm_page_free_zero(m); - - /* Remove pmap from the allpmaps list */ mtx_lock(&allpmaps_lock); LIST_REMOVE(pmap, pm_list); mtx_unlock(&allpmaps_lock); - /* Remove kernel pagetables */ - bzero(pmap->pm_l1, PAGE_SIZE); + m = PHYS_TO_VM_PAGE(DMAP_TO_PHYS((vm_offset_t)pmap->pm_l1)); + vm_page_unwire_noq(m); + vm_page_free(m); } #if 0