diff options
Diffstat (limited to 'arch/sh/kernel/ptrace.c')
-rw-r--r-- | arch/sh/kernel/ptrace.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/arch/sh/kernel/ptrace.c b/arch/sh/kernel/ptrace.c new file mode 100644 index 000000000000..1b0dfb4d8ea4 --- /dev/null +++ b/arch/sh/kernel/ptrace.c @@ -0,0 +1,320 @@ +/* + * linux/arch/sh/kernel/ptrace.c + * + * Original x86 implementation: + * By Ross Biro 1/23/92 + * edited by Linus Torvalds + * + * SuperH version: Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka + * + */ + +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/smp_lock.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/user.h> +#include <linux/slab.h> +#include <linux/security.h> + +#include <asm/io.h> +#include <asm/uaccess.h> +#include <asm/pgtable.h> +#include <asm/system.h> +#include <asm/processor.h> +#include <asm/mmu_context.h> + +/* + * does not yet catch signals sent when the child dies. + * in exit.c or in signal.c. + */ + +/* + * This routine will get a word off of the process kernel stack. + */ +static inline int get_stack_long(struct task_struct *task, int offset) +{ + unsigned char *stack; + + stack = (unsigned char *) + task->thread_info + THREAD_SIZE - sizeof(struct pt_regs) +#ifdef CONFIG_SH_DSP + - sizeof(struct pt_dspregs) +#endif + - sizeof(unsigned long); + stack += offset; + return (*((int *)stack)); +} + +/* + * This routine will put a word on the process kernel stack. + */ +static inline int put_stack_long(struct task_struct *task, int offset, + unsigned long data) +{ + unsigned char *stack; + + stack = (unsigned char *) + task->thread_info + THREAD_SIZE - sizeof(struct pt_regs) +#ifdef CONFIG_SH_DSP + - sizeof(struct pt_dspregs) +#endif + - sizeof(unsigned long); + stack += offset; + *(unsigned long *) stack = data; + return 0; +} + +/* + * Called by kernel/ptrace.c when detaching.. + * + * Make sure single step bits etc are not set. + */ +void ptrace_disable(struct task_struct *child) +{ + /* nothing to do.. */ +} + +asmlinkage int sys_ptrace(long request, long pid, long addr, long data) +{ + struct task_struct *child; + struct user * dummy = NULL; + int ret; + + lock_kernel(); + ret = -EPERM; + if (request == PTRACE_TRACEME) { + /* are we already being traced? */ + if (current->ptrace & PT_PTRACED) + goto out; + ret = security_ptrace(current->parent, current); + if (ret) + goto out; + /* set the ptrace bit in the process flags. */ + 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) /* you may not mess with init */ + 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) { + /* when I and D space are separate, these will need to be fixed. */ + case PTRACE_PEEKTEXT: /* read word at location addr. */ + 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,(unsigned long *) data); + break; + } + + /* read the word at location addr in the USER area. */ + case PTRACE_PEEKUSR: { + unsigned long tmp; + + ret = -EIO; + if ((addr & 3) || addr < 0 || + addr > sizeof(struct user) - 3) + break; + + if (addr < sizeof(struct pt_regs)) + tmp = get_stack_long(child, addr); + else if (addr >= (long) &dummy->fpu && + addr < (long) &dummy->u_fpvalid) { + if (!tsk_used_math(child)) { + if (addr == (long)&dummy->fpu.fpscr) + tmp = FPSCR_INIT; + else + tmp = 0; + } else + tmp = ((long *)&child->thread.fpu) + [(addr - (long)&dummy->fpu) >> 2]; + } else if (addr == (long) &dummy->u_fpvalid) + tmp = !!tsk_used_math(child); + else + tmp = 0; + ret = put_user(tmp, (unsigned long *)data); + break; + } + + /* when I and D space are separate, this will have to be fixed. */ + case PTRACE_POKETEXT: /* write the word at location addr. */ + case PTRACE_POKEDATA: + ret = 0; + if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data)) + break; + ret = -EIO; + break; + + case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ + ret = -EIO; + if ((addr & 3) || addr < 0 || + addr > sizeof(struct user) - 3) + break; + + if (addr < sizeof(struct pt_regs)) + ret = put_stack_long(child, addr, data); + else if (addr >= (long) &dummy->fpu && + addr < (long) &dummy->u_fpvalid) { + set_stopped_child_used_math(child); + ((long *)&child->thread.fpu) + [(addr - (long)&dummy->fpu) >> 2] = data; + ret = 0; + } else if (addr == (long) &dummy->u_fpvalid) { + conditional_stopped_child_used_math(data, child); + ret = 0; + } + break; + + case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ + case PTRACE_CONT: { /* restart after signal. */ + 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; + wake_up_process(child); + ret = 0; + break; + } + +/* + * make the child exit. Best I can do is send it a sigkill. + * perhaps it should be put in the status that it wants to + * exit. + */ + case PTRACE_KILL: { + ret = 0; + if (child->exit_state == EXIT_ZOMBIE) /* already dead */ + break; + child->exit_code = SIGKILL; + wake_up_process(child); + break; + } + + case PTRACE_SINGLESTEP: { /* set the trap flag. */ + long pc; + struct pt_regs *dummy = NULL; + + ret = -EIO; + if ((unsigned long) data > _NSIG) + break; + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + if ((child->ptrace & PT_DTRACE) == 0) { + /* Spurious delayed TF traps may occur */ + child->ptrace |= PT_DTRACE; + } + + pc = get_stack_long(child, (long)&dummy->pc); + + /* Next scheduling will set up UBC */ + if (child->thread.ubc_pc == 0) + ubc_usercnt += 1; + child->thread.ubc_pc = pc; + + child->exit_code = data; + /* give it a chance to run. */ + wake_up_process(child); + ret = 0; + break; + } + + case PTRACE_DETACH: /* detach a process that was attached. */ + ret = ptrace_detach(child, data); + break; + +#ifdef CONFIG_SH_DSP + case PTRACE_GETDSPREGS: { + unsigned long dp; + + ret = -EIO; + dp = ((unsigned long) child) + THREAD_SIZE - + sizeof(struct pt_dspregs); + if (*((int *) (dp - 4)) == SR_FD) { + copy_to_user(addr, (void *) dp, + sizeof(struct pt_dspregs)); + ret = 0; + } + break; + } + + case PTRACE_SETDSPREGS: { + unsigned long dp; + int i; + + ret = -EIO; + dp = ((unsigned long) child) + THREAD_SIZE - + sizeof(struct pt_dspregs); + if (*((int *) (dp - 4)) == SR_FD) { + copy_from_user((void *) dp, addr, + sizeof(struct pt_dspregs)); + ret = 0; + } + break; + } +#endif + default: + ret = ptrace_request(child, request, addr, data); + break; + } +out_tsk: + put_task_struct(child); +out: + unlock_kernel(); + return ret; +} + +asmlinkage void do_syscall_trace(void) +{ + struct task_struct *tsk = current; + + if (!test_thread_flag(TIF_SYSCALL_TRACE)) + return; + if (!(tsk->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. strace only continues with a signal if the + * stopping signal is not SIGTRAP. -brl + */ + if (tsk->exit_code) { + send_sig(tsk->exit_code, tsk, 1); + tsk->exit_code = 0; + } +} |