diff options
| -rw-r--r-- | arch/x86/kernel/ptrace.c | 149 |
1 files changed, 103 insertions, 46 deletions
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index 3e34b14e8846..88ed1e74cee9 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -620,12 +620,80 @@ static int ptrace_bts_drain(struct task_struct *child, 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 @@ static int ptrace_bts_config(struct task_struct *child, 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 @@ void ptrace_bts_take_timestamp(struct task_struct *tsk, { struct bts_struct rec = { .qualifier = qualifier, - .variant.jiffies = jiffies + .variant.jiffies = jiffies_64 }; ptrace_bts_write_record(tsk, &rec); @@ -743,10 +798,12 @@ void ptrace_disable(struct task_struct *child) #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); } } |