Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932437AbXLTNPg (ORCPT ); Thu, 20 Dec 2007 08:15:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760235AbXLTNP2 (ORCPT ); Thu, 20 Dec 2007 08:15:28 -0500 Received: from mga09.intel.com ([134.134.136.24]:49185 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753428AbXLTNP1 (ORCPT ); Thu, 20 Dec 2007 08:15:27 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.24,189,1196668800"; d="scan'208";a="247601704" Date: Thu, 20 Dec 2007 14:05:30 +0100 From: Markus Metzger To: ak@suse.de, hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@elte.hu, tglx@linutronix.de Cc: markus.t.metzger@intel.com, markus.t.metzger@gmail.com, suresh.b.siddha@intel.com, roland@redhat.com, akpm@linux-foundation.org, mtk.manpages@gmail.com Subject: [patch 1/5] x86, ptrace: rlimit BTS buffer allocation Message-ID: <20071220140530.A29536@sedona.ch.intel.com> Mime-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.2.5i Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5990 Lines: 224 Check the rlimit of the tracing task for total and locked memory when allocating the BTS buffer. Signed-off-by: Markus Metzger --- Index: linux-2.6-x86/arch/x86/kernel/ptrace.c =================================================================== --- linux-2.6-x86.orig/arch/x86/kernel/ptrace.c 2007-12-20 13:51:21.%N +0100 +++ linux-2.6-x86/arch/x86/kernel/ptrace.c 2007-12-20 13:51:45.%N +0100 @@ -620,12 +620,80 @@ return i; } +static int ptrace_bts_realloc(struct task_struct *child, + int size, int reduce_size) +{ + unsigned long rlim, vm; + int ret, old_size; + + if (size < 0) + return -EINVAL; + + old_size = ds_get_bts_size((void *)child->thread.ds_area_msr); + if (old_size < 0) + return old_size; + + ret = ds_free((void **)&child->thread.ds_area_msr); + if (ret < 0) + goto out; + + size >>= PAGE_SHIFT; + old_size >>= PAGE_SHIFT; + + current->mm->total_vm -= old_size; + current->mm->locked_vm -= old_size; + + if (size == 0) + goto out; + + rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT; + vm = current->mm->total_vm + size; + if (rlim < vm) { + ret = -ENOMEM; + + if (!reduce_size) + goto out; + + size = rlim - current->mm->total_vm; + if (size <= 0) + goto out; + } + + rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT; + vm = current->mm->locked_vm + size; + if (rlim < vm) { + ret = -ENOMEM; + + if (!reduce_size) + goto out; + + size = rlim - current->mm->locked_vm; + if (size <= 0) + goto out; + } + + ret = ds_allocate((void **)&child->thread.ds_area_msr, + size << PAGE_SHIFT); + if (ret < 0) + goto out; + + current->mm->total_vm += size; + current->mm->locked_vm += size; + +out: + if (child->thread.ds_area_msr) + set_tsk_thread_flag(child, TIF_DS_AREA_MSR); + else + clear_tsk_thread_flag(child, TIF_DS_AREA_MSR); + + return ret; +} + static int ptrace_bts_config(struct task_struct *child, const struct ptrace_bts_config __user *ucfg) { struct ptrace_bts_config cfg; - unsigned long debugctl_mask; - int bts_size, ret; + int bts_size, ret = 0; void *ds; if (copy_from_user(&cfg, ucfg, sizeof(cfg))) @@ -638,59 +706,46 @@ if (bts_size < 0) return bts_size; } + cfg.size = PAGE_ALIGN(cfg.size); if (bts_size != cfg.size) { - ret = ds_free((void **)&child->thread.ds_area_msr); + ret = ptrace_bts_realloc(child, cfg.size, + cfg.flags & PTRACE_BTS_O_CUT_SIZE); if (ret < 0) - return ret; + goto errout; - if (cfg.size > 0) - ret = ds_allocate((void **)&child->thread.ds_area_msr, - cfg.size); ds = (void *)child->thread.ds_area_msr; - if (ds) - set_tsk_thread_flag(child, TIF_DS_AREA_MSR); - else - clear_tsk_thread_flag(child, TIF_DS_AREA_MSR); - - if (ret < 0) - return ret; - - bts_size = ds_get_bts_size(ds); - if (bts_size <= 0) - return bts_size; } - if (ds) { - if (cfg.flags & PTRACE_BTS_O_SIGNAL) { - ret = ds_set_overflow(ds, DS_O_SIGNAL); - } else { - ret = ds_set_overflow(ds, DS_O_WRAP); - } - if (ret < 0) - return ret; - } - - debugctl_mask = ds_debugctl_mask(); - if (ds && (cfg.flags & PTRACE_BTS_O_TRACE)) { - child->thread.debugctlmsr |= debugctl_mask; - set_tsk_thread_flag(child, TIF_DEBUGCTLMSR); - } else { - /* there is no way for us to check whether we 'own' - * the respective bits in the DEBUGCTL MSR, we're - * about to clear */ - child->thread.debugctlmsr &= ~debugctl_mask; + if (cfg.flags & PTRACE_BTS_O_SIGNAL) + ret = ds_set_overflow(ds, DS_O_SIGNAL); + else + ret = ds_set_overflow(ds, DS_O_WRAP); + if (ret < 0) + goto errout; - if (!child->thread.debugctlmsr) - clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR); - } + if (cfg.flags & PTRACE_BTS_O_TRACE) + child->thread.debugctlmsr |= ds_debugctl_mask(); + else + child->thread.debugctlmsr &= ~ds_debugctl_mask(); - if (ds && (cfg.flags & PTRACE_BTS_O_SCHED)) + if (cfg.flags & PTRACE_BTS_O_SCHED) set_tsk_thread_flag(child, TIF_BTS_TRACE_TS); else clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS); - return 0; +out: + if (child->thread.debugctlmsr) + set_tsk_thread_flag(child, TIF_DEBUGCTLMSR); + else + clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR); + + return ret; + +errout: + child->thread.debugctlmsr &= ~ds_debugctl_mask(); + clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS); + goto out; } static int ptrace_bts_status(struct task_struct *child, @@ -726,7 +781,7 @@ { struct bts_struct rec = { .qualifier = qualifier, - .variant.jiffies = jiffies + .variant.jiffies = jiffies_64 }; ptrace_bts_write_record(tsk, &rec); @@ -743,10 +798,12 @@ #ifdef TIF_SYSCALL_EMU clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); #endif - ptrace_bts_config(child, /* options = */ 0); if (child->thread.ds_area_msr) { - ds_free((void **)&child->thread.ds_area_msr); - clear_tsk_thread_flag(child, TIF_DS_AREA_MSR); + ptrace_bts_realloc(child, 0, 0); + child->thread.debugctlmsr &= ~ds_debugctl_mask(); + if (!child->thread.debugctlmsr) + clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR); + clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS); } } --------------------------------------------------------------------- Intel GmbH Dornacher Strasse 1 85622 Feldkirchen/Muenchen Germany Sitz der Gesellschaft: Feldkirchen bei Muenchen Geschaeftsfuehrer: Douglas Lusk, Peter Gleissner, Hannes Schwaderer Registergericht: Muenchen HRB 47456 Ust.-IdNr. 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