/* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * 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; 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 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: { struct pt_regs *regs; unsigned long tmp = 0; 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); #ifdef CONFIG_MIPS32 /* * 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); #endif #ifdef CONFIG_MIPS64 tmp = fregs[addr - FPR_BASE]; #endif } 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 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; } #ifdef CONFIG_MIPS32 /* * 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; fregs[addr - FPR_BASE] |= data; } #endif #ifdef CONFIG_MIPS64 fregs[addr - FPR_BASE] = data; #endif 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 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_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; } static inline int audit_arch() { #ifdef CONFIG_CPU_LITTLE_ENDIAN #ifdef CONFIG_MIPS64 if (!(current->thread.mflags & MF_32BIT_REGS)) return AUDIT_ARCH_MIPSEL64; #endif /* MIPS64 */ return AUDIT_ARCH_MIPSEL; #else /* big endian... */ #ifdef CONFIG_MIPS64 if (!(current->thread.mflags & MF_32BIT_REGS)) return AUDIT_ARCH_MIPS64; #endif /* MIPS64 */ return AUDIT_ARCH_MIPS; #endif /* endian */ } /* * Notification of system call entry/exit * - triggered by current->work.syscall_trace */ asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit) { if (unlikely(current->audit_context) && entryexit) audit_syscall_exit(current, AUDITSC_RESULT(regs->regs[2]), regs->regs[2]); if (!test_thread_flag(TIF_SYSCALL_TRACE)) goto out; if (!(current->ptrace & PT_PTRACED)) goto out; /* 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 (current->exit_code) { send_sig(current->exit_code, current, 1); current->exit_code = 0; } out: if (unlikely(current->audit_context) && !entryexit) audit_syscall_entry(current, audit_arch(), regs->regs[2], regs->regs[4], regs->regs[5], regs->regs[6], regs->regs[7]); }