From owner-svn-src-head@freebsd.org Mon Nov 26 20:52:55 2018 Return-Path: Delivered-To: svn-src-head@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 2514E1144369; Mon, 26 Nov 2018 20:52:55 +0000 (UTC) (envelope-from vangyzen@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id C01DE6AA1B; Mon, 26 Nov 2018 20:52:54 +0000 (UTC) (envelope-from vangyzen@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 A1215112BB; Mon, 26 Nov 2018 20:52:54 +0000 (UTC) (envelope-from vangyzen@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id wAQKqski022339; Mon, 26 Nov 2018 20:52:54 GMT (envelope-from vangyzen@FreeBSD.org) Received: (from vangyzen@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id wAQKqsPi022337; Mon, 26 Nov 2018 20:52:54 GMT (envelope-from vangyzen@FreeBSD.org) Message-Id: <201811262052.wAQKqsPi022337@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: vangyzen set sender to vangyzen@FreeBSD.org using -f From: Eric van Gyzen Date: Mon, 26 Nov 2018 20:52:54 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r340995 - in head/sys: arm/arm arm64/arm64 riscv/riscv X-SVN-Group: head X-SVN-Commit-Author: vangyzen X-SVN-Commit-Paths: in head/sys: arm/arm arm64/arm64 riscv/riscv X-SVN-Commit-Revision: 340995 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: C01DE6AA1B X-Spamd-Result: default: False [1.48 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_SPAM_SHORT(0.27)[0.274,0]; NEURAL_SPAM_MEDIUM(0.56)[0.562,0]; NEURAL_SPAM_LONG(0.64)[0.643,0] X-Rspamd-Server: mx1.freebsd.org X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 26 Nov 2018 20:52:55 -0000 Author: vangyzen Date: Mon Nov 26 20:52:53 2018 New Revision: 340995 URL: https://svnweb.freebsd.org/changeset/base/340995 Log: Prevent kernel stack disclosure in signal delivery On arm64 and riscv platforms, sendsig() failed to zero the signal frame before copying it out to userspace. Zero it. On arm, I believe all the contents of the frame were initialized, so there was no disclosure. However, explicitly zero the whole frame because that fact could inadvertently change in the future, it's more clear to the reader, and I could be wrong in the first place. MFC after: 2 days Security: similar to FreeBSD-EN-18:12.mem and CVE-2018-17155 Sponsored by: Dell EMC Isilon Modified: head/sys/arm/arm/machdep.c head/sys/arm64/arm64/machdep.c head/sys/riscv/riscv/machdep.c Modified: head/sys/arm/arm/machdep.c ============================================================================== --- head/sys/arm/arm/machdep.c Mon Nov 26 20:50:55 2018 (r340994) +++ head/sys/arm/arm/machdep.c Mon Nov 26 20:52:53 2018 (r340995) @@ -641,6 +641,7 @@ sendsig(catcher, ksi, mask) /* make the stack aligned */ fp = (struct sigframe *)STACKALIGN(fp); /* Populate the siginfo frame. */ + bzero(&frame, sizeof(frame)); get_mcontext(td, &frame.sf_uc.uc_mcontext, 0); #ifdef VFP get_vfpcontext(td, &frame.sf_vfp); Modified: head/sys/arm64/arm64/machdep.c ============================================================================== --- head/sys/arm64/arm64/machdep.c Mon Nov 26 20:50:55 2018 (r340994) +++ head/sys/arm64/arm64/machdep.c Mon Nov 26 20:52:53 2018 (r340995) @@ -656,6 +656,7 @@ sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask fp = (struct sigframe *)STACKALIGN(fp); /* Fill in the frame to copy out */ + bzero(&frame, sizeof(frame)); get_mcontext(td, &frame.sf_uc.uc_mcontext, 0); get_fpcontext(td, &frame.sf_uc.uc_mcontext); frame.sf_si = ksi->ksi_info; Modified: head/sys/riscv/riscv/machdep.c ============================================================================== --- head/sys/riscv/riscv/machdep.c Mon Nov 26 20:50:55 2018 (r340994) +++ head/sys/riscv/riscv/machdep.c Mon Nov 26 20:52:53 2018 (r340995) @@ -582,6 +582,7 @@ sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask fp = (struct sigframe *)STACKALIGN(fp); /* Fill in the frame to copy out */ + bzero(&frame, sizeof(frame)); get_mcontext(td, &frame.sf_uc.uc_mcontext, 0); get_fpcontext(td, &frame.sf_uc.uc_mcontext); frame.sf_si = ksi->ksi_info;