1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2011 Konstantin Belousov <kib@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 */
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/elf.h>
33 #include <sys/lock.h>
34 #include <sys/malloc.h>
35 #include <sys/mutex.h>
36 #include <sys/proc.h>
37 #include <sys/ptrace.h>
38 #include <sys/reg.h>
39 #include <sys/sysent.h>
40 #include <vm/vm.h>
41 #include <vm/pmap.h>
42 #include <machine/md_var.h>
43 #include <machine/pcb.h>
44 #include <machine/frame.h>
45 #include <machine/vmparam.h>
46
47 #ifdef COMPAT_FREEBSD32
48 struct ptrace_xstate_info32 {
49 uint32_t xsave_mask1, xsave_mask2;
50 uint32_t xsave_len;
51 };
52 #endif
53
54 static bool
get_segbases(struct regset * rs,struct thread * td,void * buf,size_t * sizep)55 get_segbases(struct regset *rs, struct thread *td, void *buf,
56 size_t *sizep)
57 {
58 struct segbasereg *reg;
59 struct pcb *pcb;
60
61 if (buf != NULL) {
62 KASSERT(*sizep == sizeof(*reg), ("%s: invalid size", __func__));
63 reg = buf;
64
65 pcb = td->td_pcb;
66 reg->r_fsbase = pcb->pcb_fsbase;
67 reg->r_gsbase = pcb->pcb_gsbase;
68 }
69 *sizep = sizeof(*reg);
70 return (true);
71 }
72
73 static bool
set_segbases(struct regset * rs,struct thread * td,void * buf,size_t size)74 set_segbases(struct regset *rs, struct thread *td, void *buf,
75 size_t size)
76 {
77 struct segbasereg *reg;
78 struct pcb *pcb;
79
80 KASSERT(size == sizeof(*reg), ("%s: invalid size", __func__));
81 reg = buf;
82
83 pcb = td->td_pcb;
84 set_pcb_flags(pcb, PCB_FULL_IRET);
85 pcb->pcb_fsbase = reg->r_fsbase;
86 td->td_frame->tf_fs = _ufssel;
87 pcb->pcb_gsbase = reg->r_gsbase;
88 td->td_frame->tf_gs = _ugssel;
89
90 return (true);
91 }
92
93 static struct regset regset_segbases = {
94 .note = NT_X86_SEGBASES,
95 .size = sizeof(struct segbasereg),
96 .get = get_segbases,
97 .set = set_segbases,
98 };
99 ELF_REGSET(regset_segbases);
100
101 #ifdef COMPAT_FREEBSD32
102 static bool
get_segbases32(struct regset * rs,struct thread * td,void * buf,size_t * sizep)103 get_segbases32(struct regset *rs, struct thread *td, void *buf,
104 size_t *sizep)
105 {
106 struct segbasereg32 *reg;
107 struct pcb *pcb;
108
109 if (buf != NULL) {
110 KASSERT(*sizep == sizeof(*reg), ("%s: invalid size", __func__));
111 reg = buf;
112
113 pcb = td->td_pcb;
114 reg->r_fsbase = (uint32_t)pcb->pcb_fsbase;
115 reg->r_gsbase = (uint32_t)pcb->pcb_gsbase;
116 }
117 *sizep = sizeof(*reg);
118 return (true);
119 }
120
121 static bool
set_segbases32(struct regset * rs,struct thread * td,void * buf,size_t size)122 set_segbases32(struct regset *rs, struct thread *td, void *buf,
123 size_t size)
124 {
125 struct segbasereg32 *reg;
126 struct pcb *pcb;
127
128 KASSERT(size == sizeof(*reg), ("%s: invalid size", __func__));
129 reg = buf;
130
131 pcb = td->td_pcb;
132 set_pcb_flags(pcb, PCB_FULL_IRET);
133 pcb->pcb_fsbase = reg->r_fsbase;
134 td->td_frame->tf_fs = _ufssel;
135 pcb->pcb_gsbase = reg->r_gsbase;
136 td->td_frame->tf_gs = _ugssel;
137
138 return (true);
139 }
140
141 static struct regset regset_segbases32 = {
142 .note = NT_X86_SEGBASES,
143 .size = sizeof(struct segbasereg32),
144 .get = get_segbases32,
145 .set = set_segbases32,
146 };
147 ELF32_REGSET(regset_segbases32);
148 #endif
149
150 static int
cpu_ptrace_xstate(struct thread * td,int req,void * addr,int data)151 cpu_ptrace_xstate(struct thread *td, int req, void *addr, int data)
152 {
153 struct ptrace_xstate_info info;
154 #ifdef COMPAT_FREEBSD32
155 struct ptrace_xstate_info32 info32;
156 #endif
157 char *savefpu;
158 int error;
159
160 if (!use_xsave)
161 return (EOPNOTSUPP);
162
163 switch (req) {
164 case PT_GETXSTATE_OLD:
165 fpugetregs(td);
166 savefpu = (char *)(get_pcb_user_save_td(td) + 1);
167 error = copyout(savefpu, addr,
168 cpu_max_ext_state_size - sizeof(struct savefpu));
169 break;
170
171 case PT_SETXSTATE_OLD:
172 if (data > cpu_max_ext_state_size - sizeof(struct savefpu)) {
173 error = EINVAL;
174 break;
175 }
176 savefpu = malloc(data, M_TEMP, M_WAITOK);
177 error = copyin(addr, savefpu, data);
178 if (error == 0) {
179 fpugetregs(td);
180 error = fpusetxstate(td, savefpu, data);
181 }
182 free(savefpu, M_TEMP);
183 break;
184
185 case PT_GETXSTATE_INFO:
186 #ifdef COMPAT_FREEBSD32
187 if (SV_CURPROC_FLAG(SV_ILP32)) {
188 if (data != sizeof(info32)) {
189 error = EINVAL;
190 } else {
191 info32.xsave_len = cpu_max_ext_state_size;
192 info32.xsave_mask1 = xsave_mask;
193 info32.xsave_mask2 = xsave_mask >> 32;
194 error = copyout(&info32, addr, data);
195 }
196 } else
197 #endif
198 {
199 if (data != sizeof(info)) {
200 error = EINVAL;
201 } else {
202 bzero(&info, sizeof(info));
203 info.xsave_len = cpu_max_ext_state_size;
204 info.xsave_mask = xsave_mask;
205 error = copyout(&info, addr, data);
206 }
207 }
208 break;
209
210 case PT_GETXSTATE:
211 fpugetregs(td);
212 savefpu = (char *)(get_pcb_user_save_td(td));
213 error = copyout(savefpu, addr, cpu_max_ext_state_size);
214 break;
215
216 case PT_SETXSTATE:
217 if (data < sizeof(struct savefpu) ||
218 data > cpu_max_ext_state_size) {
219 error = EINVAL;
220 break;
221 }
222 savefpu = malloc(data, M_TEMP, M_WAITOK);
223 error = copyin(addr, savefpu, data);
224 if (error == 0)
225 error = fpusetregs(td, (struct savefpu *)savefpu,
226 savefpu + sizeof(struct savefpu), data -
227 sizeof(struct savefpu));
228 free(savefpu, M_TEMP);
229 break;
230
231 default:
232 error = EINVAL;
233 break;
234 }
235
236 return (error);
237 }
238
239 static void
cpu_ptrace_setbase(struct thread * td,int req,register_t r)240 cpu_ptrace_setbase(struct thread *td, int req, register_t r)
241 {
242 struct pcb *pcb;
243
244 pcb = td->td_pcb;
245 set_pcb_flags(pcb, PCB_FULL_IRET);
246 if (req == PT_SETFSBASE) {
247 pcb->pcb_fsbase = r;
248 td->td_frame->tf_fs = _ufssel;
249 } else {
250 pcb->pcb_gsbase = r;
251 td->td_frame->tf_gs = _ugssel;
252 }
253 }
254
255 #ifdef COMPAT_FREEBSD32
256 #define PT_I386_GETXMMREGS (PT_FIRSTMACH + 0)
257 #define PT_I386_SETXMMREGS (PT_FIRSTMACH + 1)
258
259 static int
cpu32_ptrace(struct thread * td,int req,void * addr,int data)260 cpu32_ptrace(struct thread *td, int req, void *addr, int data)
261 {
262 struct savefpu *fpstate;
263 struct pcb *pcb;
264 uint32_t r;
265 int error;
266
267 switch (req) {
268 case PT_I386_GETXMMREGS:
269 fpugetregs(td);
270 error = copyout(get_pcb_user_save_td(td), addr,
271 sizeof(*fpstate));
272 break;
273
274 case PT_I386_SETXMMREGS:
275 fpugetregs(td);
276 fpstate = get_pcb_user_save_td(td);
277 error = copyin(addr, fpstate, sizeof(*fpstate));
278 fpstate->sv_env.en_mxcsr &= cpu_mxcsr_mask;
279 break;
280
281 case PT_GETXSTATE_OLD:
282 case PT_SETXSTATE_OLD:
283 case PT_GETXSTATE_INFO:
284 case PT_GETXSTATE:
285 case PT_SETXSTATE:
286 error = cpu_ptrace_xstate(td, req, addr, data);
287 break;
288
289 case PT_GETFSBASE:
290 case PT_GETGSBASE:
291 if (!SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
292 error = EINVAL;
293 break;
294 }
295 pcb = td->td_pcb;
296 if (td == curthread)
297 update_pcb_bases(pcb);
298 r = req == PT_GETFSBASE ? pcb->pcb_fsbase : pcb->pcb_gsbase;
299 error = copyout(&r, addr, sizeof(r));
300 break;
301
302 case PT_SETFSBASE:
303 case PT_SETGSBASE:
304 if (!SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
305 error = EINVAL;
306 break;
307 }
308 error = copyin(addr, &r, sizeof(r));
309 if (error != 0)
310 break;
311 cpu_ptrace_setbase(td, req, r);
312 break;
313
314 default:
315 error = EINVAL;
316 break;
317 }
318
319 return (error);
320 }
321 #endif
322
323 int
cpu_ptrace(struct thread * td,int req,void * addr,int data)324 cpu_ptrace(struct thread *td, int req, void *addr, int data)
325 {
326 register_t *r, rv;
327 struct pcb *pcb;
328 int error;
329
330 #ifdef COMPAT_FREEBSD32
331 if (SV_CURPROC_FLAG(SV_ILP32))
332 return (cpu32_ptrace(td, req, addr, data));
333 #endif
334
335 /* Support old values of PT_GETXSTATE_OLD and PT_SETXSTATE_OLD. */
336 if (req == PT_FIRSTMACH + 0)
337 req = PT_GETXSTATE_OLD;
338 if (req == PT_FIRSTMACH + 1)
339 req = PT_SETXSTATE_OLD;
340
341 switch (req) {
342 case PT_GETXSTATE_OLD:
343 case PT_SETXSTATE_OLD:
344 case PT_GETXSTATE_INFO:
345 case PT_GETXSTATE:
346 case PT_SETXSTATE:
347 error = cpu_ptrace_xstate(td, req, addr, data);
348 break;
349
350 case PT_GETFSBASE:
351 case PT_GETGSBASE:
352 pcb = td->td_pcb;
353 if (td == curthread)
354 update_pcb_bases(pcb);
355 r = req == PT_GETFSBASE ? &pcb->pcb_fsbase : &pcb->pcb_gsbase;
356 error = copyout(r, addr, sizeof(*r));
357 break;
358
359 case PT_SETFSBASE:
360 case PT_SETGSBASE:
361 error = copyin(addr, &rv, sizeof(rv));
362 if (error != 0)
363 break;
364 if (rv >= td->td_proc->p_sysent->sv_maxuser) {
365 error = EINVAL;
366 break;
367 }
368 cpu_ptrace_setbase(td, req, rv);
369 break;
370
371 default:
372 error = EINVAL;
373 break;
374 }
375
376 return (error);
377 }
378
379 int
ptrace_set_pc(struct thread * td,unsigned long addr)380 ptrace_set_pc(struct thread *td, unsigned long addr)
381 {
382
383 td->td_frame->tf_rip = addr;
384 set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
385 return (0);
386 }
387
388 int
ptrace_single_step(struct thread * td)389 ptrace_single_step(struct thread *td)
390 {
391
392 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
393 if ((td->td_frame->tf_rflags & PSL_T) == 0) {
394 td->td_frame->tf_rflags |= PSL_T;
395 td->td_dbgflags |= TDB_STEP;
396 }
397 return (0);
398 }
399
400 int
ptrace_clear_single_step(struct thread * td)401 ptrace_clear_single_step(struct thread *td)
402 {
403
404 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
405 td->td_frame->tf_rflags &= ~PSL_T;
406 td->td_dbgflags &= ~TDB_STEP;
407 return (0);
408 }
409