From owner-svn-src-head@freebsd.org Wed May 30 03:48:28 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 A59E4EF9726; Wed, 30 May 2018 03:48:28 +0000 (UTC) (envelope-from jhibbits@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 54B026CEED; Wed, 30 May 2018 03:48:28 +0000 (UTC) (envelope-from jhibbits@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 35B0925597; Wed, 30 May 2018 03:48:28 +0000 (UTC) (envelope-from jhibbits@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id w4U3mS6g066085; Wed, 30 May 2018 03:48:28 GMT (envelope-from jhibbits@FreeBSD.org) Received: (from jhibbits@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w4U3mSKM066084; Wed, 30 May 2018 03:48:28 GMT (envelope-from jhibbits@FreeBSD.org) Message-Id: <201805300348.w4U3mSKM066084@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: jhibbits set sender to jhibbits@FreeBSD.org using -f From: Justin Hibbits Date: Wed, 30 May 2018 03:48:28 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r334370 - head/sys/cddl/dev/dtrace/powerpc X-SVN-Group: head X-SVN-Commit-Author: jhibbits X-SVN-Commit-Paths: head/sys/cddl/dev/dtrace/powerpc X-SVN-Commit-Revision: 334370 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.26 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: Wed, 30 May 2018 03:48:28 -0000 Author: jhibbits Date: Wed May 30 03:48:27 2018 New Revision: 334370 URL: https://svnweb.freebsd.org/changeset/base/334370 Log: Protect dtrace_getpcstack() from a NULL stack pointer in a trap frame Found when trying to use lockstat on a POWER9, the stack pointer (r1) could be NULL, and result in a NULL pointer dereference, crashing the kernel. Modified: head/sys/cddl/dev/dtrace/powerpc/dtrace_isa.c Modified: head/sys/cddl/dev/dtrace/powerpc/dtrace_isa.c ============================================================================== --- head/sys/cddl/dev/dtrace/powerpc/dtrace_isa.c Wed May 30 03:40:02 2018 (r334369) +++ head/sys/cddl/dev/dtrace/powerpc/dtrace_isa.c Wed May 30 03:48:27 2018 (r334370) @@ -98,6 +98,7 @@ static __inline uintptr_t dtrace_next_sp(uintptr_t sp) { vm_offset_t callpc; + uintptr_t *r1; struct trapframe *frame; #ifdef __powerpc64__ @@ -114,7 +115,10 @@ dtrace_next_sp(uintptr_t sp) callpc + OFFSET == (vm_offset_t) &asttrapexit)) { /* Access the trap frame */ frame = (struct trapframe *)(sp + FRAME_OFFSET); - return (*(uintptr_t *)(frame->fixreg[1])); + r1 = (uintptr_t *)frame->fixreg[1]; + if (r1 == NULL) + return (0); + return (*r1); } return (*(uintptr_t*)sp);