diff options
Diffstat (limited to 'arch/mips/kernel/ptrace32.c')
-rw-r--r-- | arch/mips/kernel/ptrace32.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/arch/mips/kernel/ptrace32.c b/arch/mips/kernel/ptrace32.c new file mode 100644 index 00000000000..611dee919d5 --- /dev/null +++ b/arch/mips/kernel/ptrace32.c @@ -0,0 +1,285 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 1992 Ross Biro + * Copyright (C) Linus Torvalds + * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle + * Copyright (C) 1996 David S. Miller + * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com + * Copyright (C) 1999 MIPS Technologies, Inc. + * Copyright (C) 2000 Ulf Carlsson + * + * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit + * binaries. + */ +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/smp.h> +#include <linux/smp_lock.h> +#include <linux/user.h> +#include <linux/security.h> + +#include <asm/cpu.h> +#include <asm/fpu.h> +#include <asm/mipsregs.h> +#include <asm/pgtable.h> +#include <asm/page.h> +#include <asm/system.h> +#include <asm/uaccess.h> +#include <asm/bootinfo.h> + +/* + * Tracing a 32-bit process with a 64-bit strace and vice versa will not + * work. I don't know how to fix this. + */ +asmlinkage int sys32_ptrace(int request, int pid, int addr, int data) +{ + struct task_struct *child; + int ret; + +#if 0 + printk("ptrace(r=%d,pid=%d,addr=%08lx,data=%08lx)\n", + (int) request, (int) pid, (unsigned long) addr, + (unsigned long) data); +#endif + lock_kernel(); + ret = -EPERM; + if (request == PTRACE_TRACEME) { + /* are we already being traced? */ + if (current->ptrace & PT_PTRACED) + goto out; + if ((ret = security_ptrace(current->parent, current))) + 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 int 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 int *) (unsigned long) data); + break; + } + + /* Read the word at location addr in the USER area. */ + case PTRACE_PEEKUSR: { + struct pt_regs *regs; + unsigned int tmp; + + regs = (struct pt_regs *) ((unsigned long) child->thread_info + + THREAD_SIZE - 32 - sizeof(struct pt_regs)); + ret = 0; /* Default return value. */ + + switch (addr) { + case 0 ... 31: + tmp = regs->regs[addr]; + break; + case FPR_BASE ... FPR_BASE + 31: + if (tsk_used_math(child)) { + fpureg_t *fregs = get_fpu_regs(child); + + /* + * The odd registers are actually the high + * order bits of the values stored in the even + * registers - unless we're using r2k_switch.S. + */ + if (addr & 1) + tmp = (unsigned long) (fregs[((addr & ~1) - 32)] >> 32); + else + tmp = (unsigned long) (fregs[(addr - 32)] & 0xffffffff); + } else { + tmp = -1; /* FP not yet used */ + } + break; + case PC: + tmp = regs->cp0_epc; + break; + case CAUSE: + tmp = regs->cp0_cause; + break; + case BADVADDR: + tmp = regs->cp0_badvaddr; + break; + case MMHI: + tmp = regs->hi; + break; + case MMLO: + tmp = regs->lo; + break; + case FPC_CSR: + if (cpu_has_fpu) + tmp = child->thread.fpu.hard.fcr31; + else + tmp = child->thread.fpu.soft.fcr31; + break; + case FPC_EIR: { /* implementation / version register */ + unsigned int flags; + + if (!cpu_has_fpu) + break; + + flags = read_c0_status(); + __enable_fpu(); + __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp)); + write_c0_status(flags); + break; + } + default: + tmp = 0; + ret = -EIO; + goto out_tsk; + } + ret = put_user(tmp, (unsigned *) (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: { + struct pt_regs *regs; + ret = 0; + regs = (struct pt_regs *) ((unsigned long) child->thread_info + + THREAD_SIZE - 32 - sizeof(struct pt_regs)); + + switch (addr) { + case 0 ... 31: + regs->regs[addr] = data; + break; + case FPR_BASE ... FPR_BASE + 31: { + fpureg_t *fregs = get_fpu_regs(child); + + if (!tsk_used_math(child)) { + /* FP not yet used */ + memset(&child->thread.fpu.hard, ~0, + sizeof(child->thread.fpu.hard)); + child->thread.fpu.hard.fcr31 = 0; + } + /* + * The odd registers are actually the high order bits + * of the values stored in the even registers - unless + * we're using r2k_switch.S. + */ + if (addr & 1) { + fregs[(addr & ~1) - FPR_BASE] &= 0xffffffff; + fregs[(addr & ~1) - FPR_BASE] |= ((unsigned long long) data) << 32; + } else { + fregs[addr - FPR_BASE] &= ~0xffffffffLL; + /* Must cast, lest sign extension fill upper + bits! */ + fregs[addr - FPR_BASE] |= (unsigned int)data; + } + break; + } + case PC: + regs->cp0_epc = data; + break; + case MMHI: + regs->hi = data; + break; + case MMLO: + regs->lo = data; + break; + case FPC_CSR: + if (cpu_has_fpu) + child->thread.fpu.hard.fcr31 = data; + else + child->thread.fpu.soft.fcr31 = data; + break; + default: + /* The rest are not allowed. */ + ret = -EIO; + break; + } + break; + } + + case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ + case PTRACE_CONT: { /* restart after signal. */ + ret = -EIO; + if ((unsigned int) 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_DETACH: /* detach a process that was attached. */ + ret = ptrace_detach(child, data); + break; + + default: + ret = ptrace_request(child, request, addr, data); + break; + } + +out_tsk: + put_task_struct(child); +out: + unlock_kernel(); + return ret; +} |