1 /* $NetBSD: linux_ptrace.c,v 1.14 2008/12/17 20:51:33 cegger Exp $ */ 2 3 /*- 4 * Copyright (c) 1999 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matthias Scheler. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.14 2008/12/17 20:51:33 cegger Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/malloc.h> 38 #include <sys/mount.h> 39 #include <sys/proc.h> 40 #include <sys/ptrace.h> 41 #include <sys/systm.h> 42 #include <sys/syscallargs.h> 43 #include <uvm/uvm_extern.h> 44 45 #include <machine/reg.h> 46 47 #include <compat/linux/common/linux_types.h> 48 #include <compat/linux/common/linux_ptrace.h> 49 #include <compat/linux/common/linux_signal.h> 50 51 #include <compat/linux/common/linux_util.h> 52 #include <compat/linux/common/linux_machdep.h> 53 #include <compat/linux/common/linux_emuldata.h> 54 #include <compat/linux/common/linux_exec.h> /* for emul_linux */ 55 56 #include <compat/linux/linux_syscallargs.h> 57 58 #include <lib/libkern/libkern.h> /* for offsetof() */ 59 60 /* 61 * On ARMv2, uregs contains R0--R15, orig_R0. 62 * On ARMv3 and later, it's R0--R15, CPSR, orig_R0. 63 * As far as I can see, Linux doesn't initialise orig_R0 on ARMv2, so we 64 * just produce the ARMv3 version. 65 */ 66 67 struct linux_reg { 68 long uregs[18]; 69 }; 70 71 #define LINUX_REG_R0 0 72 #define LINUX_REG_R1 1 73 #define LINUX_REG_R2 2 74 #define LINUX_REG_R3 3 75 #define LINUX_REG_R4 4 76 #define LINUX_REG_R5 5 77 #define LINUX_REG_R6 6 78 #define LINUX_REG_R7 7 79 #define LINUX_REG_R8 8 80 #define LINUX_REG_R9 9 81 #define LINUX_REG_R10 10 82 #define LINUX_REG_FP 11 83 #define LINUX_REG_IP 12 84 #define LINUX_REG_SP 13 85 #define LINUX_REG_LR 14 86 #define LINUX_REG_PC 15 87 #define LINUX_REG_CPSR 16 88 #define LINUX_REG_ORIG_R0 17 89 90 int linux_ptrace_disabled = 1; /* bitrotted */ 91 92 int 93 linux_sys_ptrace_arch(struct lwp *l, const struct linux_sys_ptrace_args *uap, register_t *retval) 94 { 95 /* { 96 syscallarg(int) request; 97 syscallarg(int) pid; 98 syscallarg(int) addr; 99 syscallarg(int) data; 100 } */ 101 struct proc *p = l->l_proc; 102 int request, error; 103 struct proc *t; /* target process */ 104 struct lwp *lt; 105 struct reg *regs = NULL; 106 struct fpreg *fpregs = NULL; 107 struct linux_reg *linux_regs = NULL; 108 struct linux_fpreg *linux_fpregs = NULL; 109 110 if (linux_ptrace_disabled) 111 return ENOSYS; 112 113 request = SCARG(uap, request); 114 115 if ((request != LINUX_PTRACE_GETREGS) && 116 (request != LINUX_PTRACE_SETREGS)) 117 return EIO; 118 119 /* Find the process we're supposed to be operating on. */ 120 if ((t = pfind(SCARG(uap, pid))) == NULL) 121 return ESRCH; 122 123 /* 124 * You can't do what you want to the process if: 125 * (1) It's not being traced at all, 126 */ 127 if (!ISSET(t->p_slflag, PSL_TRACED)) 128 return EPERM; 129 130 /* 131 * (2) it's being traced by procfs (which has 132 * different signal delivery semantics), 133 */ 134 if (ISSET(t->p_slflag, PSL_FSTRACE)) 135 return EBUSY; 136 137 /* 138 * (3) it's not being traced by _you_, or 139 */ 140 if (t->p_pptr != p) 141 return EBUSY; 142 143 /* 144 * (4) it's not currently stopped. 145 */ 146 if (t->p_stat != SSTOP || !t->p_waited) 147 return EBUSY; 148 149 /* XXX NJWLWP 150 * The entire ptrace interface needs work to be useful to 151 * a process with multiple LWPs. For the moment, we'll 152 * just kluge this and fail on others. 153 */ 154 155 if (p->p_nlwps > 1) 156 return (ENOSYS); 157 158 lt = LIST_FIRST(&t->p_lwps); 159 160 *retval = 0; 161 162 switch (request) { 163 case LINUX_PTRACE_GETREGS: 164 regs = malloc(sizeof(struct reg), M_TEMP, M_WAITOK); 165 linux_regs = malloc(sizeof(struct linux_reg), 166 M_TEMP, M_WAITOK); 167 168 error = process_read_regs(lt, regs); 169 if (error != 0) 170 goto out; 171 172 memcpy(linux_regs->uregs, regs->r, 13 * sizeof(register_t)); 173 linux_regs->uregs[LINUX_REG_SP] = regs->r_sp; 174 linux_regs->uregs[LINUX_REG_LR] = regs->r_lr; 175 linux_regs->uregs[LINUX_REG_PC] = regs->r_pc; 176 linux_regs->uregs[LINUX_REG_CPSR] = regs->r_cpsr; 177 linux_regs->uregs[LINUX_REG_ORIG_R0] = regs->r[0]; 178 179 error = copyout(linux_regs, (void *)SCARG(uap, data), 180 sizeof(struct linux_reg)); 181 goto out; 182 183 case LINUX_PTRACE_SETREGS: 184 regs = malloc(sizeof(struct reg), M_TEMP, M_WAITOK); 185 linux_regs = malloc(sizeof(struct linux_reg), 186 M_TEMP, M_WAITOK); 187 188 error = copyin((void *)SCARG(uap, data), linux_regs, 189 sizeof(struct linux_reg)); 190 if (error != 0) 191 goto out; 192 193 memcpy(regs->r, linux_regs->uregs, 13 * sizeof(register_t)); 194 regs->r_sp = linux_regs->uregs[LINUX_REG_SP]; 195 regs->r_lr = linux_regs->uregs[LINUX_REG_LR]; 196 regs->r_pc = linux_regs->uregs[LINUX_REG_PC]; 197 regs->r_cpsr = linux_regs->uregs[LINUX_REG_CPSR]; 198 199 error = process_write_regs(lt, regs); 200 goto out; 201 202 default: 203 /* never reached */ 204 break; 205 } 206 207 return EIO; 208 209 out: 210 if (regs) 211 free(regs, M_TEMP); 212 if (fpregs) 213 free(fpregs, M_TEMP); 214 if (linux_regs) 215 free(linux_regs, M_TEMP); 216 if (linux_fpregs) 217 free(linux_fpregs, M_TEMP); 218 return (error); 219 220 } 221