Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933519Ab3DGL5D (ORCPT ); Sun, 7 Apr 2013 07:57:03 -0400 Received: from e8.ny.us.ibm.com ([32.97.182.138]:39131 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761396Ab3DGL5B (ORCPT ); Sun, 7 Apr 2013 07:57:01 -0400 Date: Sun, 7 Apr 2013 17:21:14 +0530 From: Srikar Dronamraju To: Anton Arapov Cc: Oleg Nesterov , LKML , Josh Stone , Frank Eigler , Peter Zijlstra , Ingo Molnar , Ananth N Mavinakayanahalli , adrian.m.negreanu@intel.com, Torsten.Polle@gmx.de Subject: Re: [PATCH v1 4/9] uretprobes/ppc: Hijack return address Message-ID: <20130407115114.GD2186@linux.vnet.ibm.com> Reply-To: Srikar Dronamraju References: <1365004839-21982-1-git-send-email-anton@redhat.com> <1365004839-21982-5-git-send-email-anton@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1365004839-21982-5-git-send-email-anton@redhat.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13040711-9360-0000-0000-000011A2557C Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2059 Lines: 58 * Anton Arapov [2013-04-03 18:00:34]: > Hijack the return address and replace it with a trampoline address. > PowerPC implementation. > > Signed-off-by: Anton Arapov Acked-by: Srikar Dronamraju > --- > arch/powerpc/include/asm/uprobes.h | 1 + > arch/powerpc/kernel/uprobes.c | 13 +++++++++++++ > 2 files changed, 14 insertions(+) > > diff --git a/arch/powerpc/include/asm/uprobes.h b/arch/powerpc/include/asm/uprobes.h > index b532060..2301602 100644 > --- a/arch/powerpc/include/asm/uprobes.h > +++ b/arch/powerpc/include/asm/uprobes.h > @@ -51,4 +51,5 @@ extern int arch_uprobe_post_xol(struct arch_uprobe *aup, struct pt_regs *regs); > extern bool arch_uprobe_xol_was_trapped(struct task_struct *tsk); > extern int arch_uprobe_exception_notify(struct notifier_block *self, unsigned long val, void *data); > extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs); > +extern unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs); > #endif /* _ASM_UPROBES_H */ > diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c > index bc77834..567b975 100644 > --- a/arch/powerpc/kernel/uprobes.c > +++ b/arch/powerpc/kernel/uprobes.c > @@ -188,3 +188,16 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs) > > return false; > } > + > +unsigned long > +arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs) > +{ > + unsigned long orig_ret_vaddr; > + > + orig_ret_vaddr = regs->link; > + > + /* Replace the return addr with trampoline addr */ > + regs->link = trampoline_vaddr; > + > + return orig_ret_vaddr; > +} > -- > 1.8.1.4 > -- Thanks and Regards Srikar Dronamraju -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/