From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764894AbXLQV2V (ORCPT ); Mon, 17 Dec 2007 16:28:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764822AbXLQV1S (ORCPT ); Mon, 17 Dec 2007 16:27:18 -0500 Received: from rv-out-0910.google.com ([209.85.198.187]:21847 "EHLO rv-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762408AbXLQV1Q (ORCPT ); Mon, 17 Dec 2007 16:27:16 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:content-type:date:message-id:mime-version:x-mailer:content-transfer-encoding; b=l8eQbBrv+tscM4s+MJ52gV2pu1Ch/YJWCiJqShVmK94mWiQ8EKxAqjwVmkF9VrfEIPaUuLhKNrRJYPhgggtR/c+ugOq+keLDrZiP8aiSBgb+/8Sxlip8zVADk4gwdkAfrEe+jgG/+x0hzJ61a4Dn0l/qfhDbgM2SV7lma8LEVUE= Subject: [PATCH 2/4] x86: kprobe cleanup resume_execution From: Harvey Harrison To: Ingo Molnar Cc: Ananth N Mavinakayanahalli , Jim Keniston , Roland McGrath , Arjan van de Ven , prasanna@in.ibm.com, anil.s.keshavamurthy@intel.com, davem@davemloft.net, systemtap-ml , LKML , Andrew Morton Content-Type: text/plain Date: Mon, 17 Dec 2007 13:27:01 -0800 Message-Id: <1197926821.23402.29.camel@brick> Mime-Version: 1.0 X-Mailer: Evolution 2.12.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch cleans up and fixes bugs in resume_execution on x86-64. Kprobes for x86-64 may cause a kernel crash if it inserted on "iret" instruction. "call absolute" case 0x9a is invalid on x86-64, so we don't need treat it, leave it ifdef X86_32. - Add "iret"(0xcf) case.to X86_64 - Fold jmp absolute (0xea) handling into iret/ret/lret handling Based on patch from Masami Hiramatsu Signed-off-by: Harvey Harrison --- arch/x86/kernel/kprobes.c | 11 +++-------- 1 files changed, 3 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c index 9130c01..64c702c 100644 --- a/arch/x86/kernel/kprobes.c +++ b/arch/x86/kernel/kprobes.c @@ -748,12 +748,13 @@ static void __kprobes resume_execution(struct kprobe *p, *tos &= ~(TF_MASK | IF_MASK); *tos |= kcb->kprobe_old_flags; break; - case 0xc2: /* ret/lret */ + case 0xc2: /* iret/ret/lret */ case 0xc3: case 0xca: case 0xcb: + case 0xcf: + case 0xea: /* jmp absolute -- ip is correct */ #ifdef CONFIG_X86_32 - case 0xcf: /* iret */ /* ip is already adjusted, no more changes required */ p->ainsn.boostable = 1; #endif @@ -783,12 +784,6 @@ static void __kprobes resume_execution(struct kprobe *p, goto no_change; } break; - case 0xea: /* jmp absolute -- ip is correct */ -#ifdef CONFIG_X86_32 - /* ip is already adjusted, no more changes required */ - p->ainsn.boostable = 1; -#endif - goto no_change; default: break; } -- 1.5.4.rc0.1083.gf568