From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754821Ab2J3Bl5 (ORCPT ); Mon, 29 Oct 2012 21:41:57 -0400 Received: from smtp.outflux.net ([198.145.64.163]:56171 "EHLO smtp.outflux.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751629Ab2J3Bl4 (ORCPT ); Mon, 29 Oct 2012 21:41:56 -0400 From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Russell King , Will Deacon , Will Drewry , Geremy Condra , Kees Cook Subject: [PATCH 2/4] arch/arm: move secure_computing into trace Date: Mon, 29 Oct 2012 17:41:20 -0700 Message-Id: <1351557682-20983-3-git-send-email-keescook@chromium.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1351557682-20983-1-git-send-email-keescook@chromium.org> References: <1351557682-20983-1-git-send-email-keescook@chromium.org> X-HELO: www.outflux.net Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Will Drewry There is very little difference in the TIF_SECCOMP and TIF_SYSCALL_TRACE path in entry-common.S. In order to add support for CONFIG_HAVE_ARCH_SECCOMP_FILTER without mangling the assembly too badly, seccomp was moved into the syscall_trace_enter() handler. Additionally, the return value for secure_computing() is now checked and a -1 value will result in the system call being skipped. Signed-off-by: Will Drewry Signed-off-by: Kees Cook --- arch/arm/kernel/entry-common.S | 9 ++------- arch/arm/kernel/ptrace.c | 3 +++ 2 files changed, 5 insertions(+), 7 deletions(-) diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 3471175..c781012 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -418,13 +418,8 @@ local_restart: stmdb sp!, {r4, r5} @ push fifth and sixth args #ifdef CONFIG_SECCOMP - tst r10, #_TIF_SECCOMP - beq 1f - mov r0, scno - bl __secure_computing - add r0, sp, #S_R0 + S_OFF @ pointer to regs - ldmia r0, {r0 - r3} @ have to reload r0 - r3 -1: + tst r10, #_TIF_SECCOMP @ is seccomp enabled? + bne __sys_trace #endif tst r10, #_TIF_SYSCALL_WORK @ are we tracing syscalls? diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c index 739db3a..aa4d93f 100644 --- a/arch/arm/kernel/ptrace.c +++ b/arch/arm/kernel/ptrace.c @@ -923,6 +923,9 @@ static int ptrace_syscall_trace(struct pt_regs *regs, int scno, current_thread_info()->syscall = scno; + if (dir == PTRACE_SYSCALL_ENTER && secure_computing(scno) == -1) + return -1; + if (!test_thread_flag(TIF_SYSCALL_TRACE)) return scno; -- 1.7.9.5