From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/cris/arch-v10/kernel/ptrace.c | 314 +++++++++++++++++++++++++++++++++++++ 1 file changed, 314 insertions(+) create mode 100644 arch/cris/arch-v10/kernel/ptrace.c (limited to 'arch/cris/arch-v10/kernel/ptrace.c') diff --git a/arch/cris/arch-v10/kernel/ptrace.c b/arch/cris/arch-v10/kernel/ptrace.c new file mode 100644 index 00000000000..da15db8ae48 --- /dev/null +++ b/arch/cris/arch-v10/kernel/ptrace.c @@ -0,0 +1,314 @@ +/* + * Copyright (C) 2000-2003, Axis Communications AB. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +/* + * Determines which bits in DCCR the user has access to. + * 1 = access, 0 = no access. + */ +#define DCCR_MASK 0x0000001f /* XNZVC */ + +/* + * Get contents of register REGNO in task TASK. + */ +inline long get_reg(struct task_struct *task, unsigned int regno) +{ + /* USP is a special case, it's not in the pt_regs struct but + * in the tasks thread struct + */ + + if (regno == PT_USP) + return task->thread.usp; + else if (regno < PT_MAX) + return ((unsigned long *)user_regs(task->thread_info))[regno]; + else + return 0; +} + +/* + * Write contents of register REGNO in task TASK. + */ +inline int put_reg(struct task_struct *task, unsigned int regno, + unsigned long data) +{ + if (regno == PT_USP) + task->thread.usp = data; + else if (regno < PT_MAX) + ((unsigned long *)user_regs(task->thread_info))[regno] = data; + else + return -1; + return 0; +} + +/* + * Called by kernel/ptrace.c when detaching. + * + * Make sure the single step bit is not set. + */ +void +ptrace_disable(struct task_struct *child) +{ + /* Todo - pending singlesteps? */ +} + +/* + * Note that this implementation of ptrace behaves differently from vanilla + * ptrace. Contrary to what the man page says, in the PTRACE_PEEKTEXT, + * PTRACE_PEEKDATA, and PTRACE_PEEKUSER requests the data variable is not + * ignored. Instead, the data variable is expected to point at a location + * (in user space) where the result of the ptrace call is written (instead of + * being returned). + */ +asmlinkage int +sys_ptrace(long request, long pid, long addr, long data) +{ + struct task_struct *child; + int ret; + unsigned long __user *datap = (unsigned long __user *)data; + + lock_kernel(); + ret = -EPERM; + + if (request == PTRACE_TRACEME) { + if (current->ptrace & PT_PTRACED) + goto out; + + current->ptrace |= PT_PTRACED; + ret = 0; + goto out; + } + + ret = -ESRCH; + read_lock(&tasklist_lock); + child = find_task_by_pid(pid); + + if (child) + get_task_struct(child); + + read_unlock(&tasklist_lock); + + if (!child) + goto out; + + ret = -EPERM; + + if (pid == 1) /* Leave the init process alone! */ + goto out_tsk; + + if (request == PTRACE_ATTACH) { + ret = ptrace_attach(child); + goto out_tsk; + } + + ret = ptrace_check_attach(child, request == PTRACE_KILL); + if (ret < 0) + goto out_tsk; + + switch (request) { + /* Read word at location address. */ + case PTRACE_PEEKTEXT: + case PTRACE_PEEKDATA: { + unsigned long tmp; + int copied; + + copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); + ret = -EIO; + + if (copied != sizeof(tmp)) + break; + + ret = put_user(tmp,datap); + break; + } + + /* Read the word at location address in the USER area. */ + case PTRACE_PEEKUSR: { + unsigned long tmp; + + ret = -EIO; + if ((addr & 3) || addr < 0 || addr > PT_MAX << 2) + break; + + tmp = get_reg(child, addr >> 2); + ret = put_user(tmp, datap); + break; + } + + /* Write the word at location address. */ + case PTRACE_POKETEXT: + case PTRACE_POKEDATA: + ret = 0; + + if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data)) + break; + + ret = -EIO; + break; + + /* Write the word at location address in the USER area. */ + case PTRACE_POKEUSR: + ret = -EIO; + if ((addr & 3) || addr < 0 || addr > PT_MAX << 2) + break; + + addr >>= 2; + + if (addr == PT_DCCR) { + /* don't allow the tracing process to change stuff like + * interrupt enable, kernel/user bit, dma enables etc. + */ + data &= DCCR_MASK; + data |= get_reg(child, PT_DCCR) & ~DCCR_MASK; + } + if (put_reg(child, addr, data)) + break; + ret = 0; + break; + + case PTRACE_SYSCALL: + case PTRACE_CONT: + ret = -EIO; + + if ((unsigned long) data > _NSIG) + break; + + if (request == PTRACE_SYSCALL) { + set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + } + else { + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + } + + child->exit_code = data; + + /* TODO: make sure any pending breakpoint is killed */ + wake_up_process(child); + ret = 0; + + break; + + /* Make the child exit by sending it a sigkill. */ + case PTRACE_KILL: + ret = 0; + + if (child->state == TASK_ZOMBIE) + break; + + child->exit_code = SIGKILL; + + /* TODO: make sure any pending breakpoint is killed */ + wake_up_process(child); + break; + + /* Set the trap flag. */ + case PTRACE_SINGLESTEP: + ret = -EIO; + + if ((unsigned long) data > _NSIG) + break; + + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + + /* TODO: set some clever breakpoint mechanism... */ + + child->exit_code = data; + wake_up_process(child); + ret = 0; + break; + + case PTRACE_DETACH: + ret = ptrace_detach(child, data); + break; + + /* Get all GP registers from the child. */ + case PTRACE_GETREGS: { + int i; + unsigned long tmp; + + for (i = 0; i <= PT_MAX; i++) { + tmp = get_reg(child, i); + + if (put_user(tmp, datap)) { + ret = -EFAULT; + goto out_tsk; + } + + data += sizeof(long); + } + + ret = 0; + break; + } + + /* Set all GP registers in the child. */ + case PTRACE_SETREGS: { + int i; + unsigned long tmp; + + for (i = 0; i <= PT_MAX; i++) { + if (get_user(tmp, datap)) { + ret = -EFAULT; + goto out_tsk; + } + + if (i == PT_DCCR) { + tmp &= DCCR_MASK; + tmp |= get_reg(child, PT_DCCR) & ~DCCR_MASK; + } + + put_reg(child, i, tmp); + data += sizeof(long); + } + + ret = 0; + break; + } + + default: + ret = ptrace_request(child, request, addr, data); + break; + } +out_tsk: + put_task_struct(child); +out: + unlock_kernel(); + return ret; +} + +void do_syscall_trace(void) +{ + if (!test_thread_flag(TIF_SYSCALL_TRACE)) + return; + + if (!(current->ptrace & PT_PTRACED)) + return; + + /* the 0x80 provides a way for the tracing parent to distinguish + between a syscall stop and SIGTRAP delivery */ + ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) + ? 0x80 : 0)); + + /* + * This isn't the same as continuing with a signal, but it will do for + * normal use. + */ + if (current->exit_code) { + send_sig(current->exit_code, current, 1); + current->exit_code = 0; + } +} -- cgit v1.2.3