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 if (td == curthread)
67 update_pcb_bases(pcb);
68 reg->r_fsbase = pcb->pcb_fsbase;
69 reg->r_gsbase = pcb->pcb_gsbase;
70 }
71 *sizep = sizeof(*reg);
72 return (true);
73 }
74
75 static bool
set_segbases(struct regset * rs,struct thread * td,void * buf,size_t size)76 set_segbases(struct regset *rs, struct thread *td, void *buf,
77 size_t size)
78 {
79 struct segbasereg *reg;
80 struct pcb *pcb;
81
82 KASSERT(size == sizeof(*reg), ("%s: invalid size", __func__));
83 reg = buf;
84
85 pcb = td->td_pcb;
86 set_pcb_flags(pcb, PCB_FULL_IRET);
87 pcb->pcb_fsbase = reg->r_fsbase;
88 td->td_frame->tf_fs = _ufssel;
89 pcb->pcb_gsbase = reg->r_gsbase;
90 td->td_frame->tf_gs = _ugssel;
91
92 return (true);
93 }
94
95 static struct regset regset_segbases = {
96 .note = NT_X86_SEGBASES,
97 .size = sizeof(struct segbasereg),
98 .get = get_segbases,
99 .set = set_segbases,
100 };
101 ELF_REGSET(regset_segbases);
102
103 #ifdef COMPAT_FREEBSD32
104 static bool
get_segbases32(struct regset * rs,struct thread * td,void * buf,size_t * sizep)105 get_segbases32(struct regset *rs, struct thread *td, void *buf,
106 size_t *sizep)
107 {
108 struct segbasereg32 *reg;
109 struct pcb *pcb;
110
111 if (buf != NULL) {
112 KASSERT(*sizep == sizeof(*reg), ("%s: invalid size", __func__));
113 reg = buf;
114
115 pcb = td->td_pcb;
116 if (td == curthread)
117 update_pcb_bases(pcb);
118 reg->r_fsbase = (uint32_t)pcb->pcb_fsbase;
119 reg->r_gsbase = (uint32_t)pcb->pcb_gsbase;
120 }
121 *sizep = sizeof(*reg);
122 return (true);
123 }
124
125 static bool
set_segbases32(struct regset * rs,struct thread * td,void * buf,size_t size)126 set_segbases32(struct regset *rs, struct thread *td, void *buf,
127 size_t size)
128 {
129 struct segbasereg32 *reg;
130 struct pcb *pcb;
131
132 KASSERT(size == sizeof(*reg), ("%s: invalid size", __func__));
133 reg = buf;
134
135 pcb = td->td_pcb;
136 set_pcb_flags(pcb, PCB_FULL_IRET);
137 pcb->pcb_fsbase = reg->r_fsbase;
138 td->td_frame->tf_fs = _ufssel;
139 pcb->pcb_gsbase = reg->r_gsbase;
140 td->td_frame->tf_gs = _ugssel;
141
142 return (true);
143 }
144
145 static struct regset regset_segbases32 = {
146 .note = NT_X86_SEGBASES,
147 .size = sizeof(struct segbasereg32),
148 .get = get_segbases32,
149 .set = set_segbases32,
150 };
151 ELF32_REGSET(regset_segbases32);
152 #endif
153
154 static int
cpu_ptrace_xstate(struct thread * td,int req,void * addr,int data)155 cpu_ptrace_xstate(struct thread *td, int req, void *addr, int data)
156 {
157 struct ptrace_xstate_info info;
158 #ifdef COMPAT_FREEBSD32
159 struct ptrace_xstate_info32 info32;
160 #endif
161 char *savefpu;
162 int error;
163
164 if (!use_xsave)
165 return (EOPNOTSUPP);
166
167 switch (req) {
168 case PT_GETXSTATE_OLD:
169 fpugetregs(td);
170 savefpu = (char *)(get_pcb_user_save_td(td) + 1);
171 error = copyout(savefpu, addr,
172 cpu_max_ext_state_size - sizeof(struct savefpu));
173 break;
174
175 case PT_SETXSTATE_OLD:
176 if (data > cpu_max_ext_state_size - sizeof(struct savefpu)) {
177 error = EINVAL;
178 break;
179 }
180 savefpu = malloc(data, M_TEMP, M_WAITOK);
181 error = copyin(addr, savefpu, data);
182 if (error == 0) {
183 fpugetregs(td);
184 error = fpusetxstate(td, savefpu, data);
185 }
186 free(savefpu, M_TEMP);
187 break;
188
189 case PT_GETXSTATE_INFO:
190 #ifdef COMPAT_FREEBSD32
191 if (SV_CURPROC_FLAG(SV_ILP32)) {
192 if (data != sizeof(info32)) {
193 error = EINVAL;
194 } else {
195 info32.xsave_len = cpu_max_ext_state_size;
196 info32.xsave_mask1 = xsave_mask;
197 info32.xsave_mask2 = xsave_mask >> 32;
198 error = copyout(&info32, addr, data);
199 }
200 } else
201 #endif
202 {
203 if (data != sizeof(info)) {
204 error = EINVAL;
205 } else {
206 bzero(&info, sizeof(info));
207 info.xsave_len = cpu_max_ext_state_size;
208 info.xsave_mask = xsave_mask;
209 error = copyout(&info, addr, data);
210 }
211 }
212 break;
213
214 case PT_GETXSTATE:
215 fpugetregs(td);
216 savefpu = (char *)(get_pcb_user_save_td(td));
217 error = copyout(savefpu, addr, cpu_max_ext_state_size);
218 break;
219
220 case PT_SETXSTATE:
221 if (data < sizeof(struct savefpu) ||
222 data > cpu_max_ext_state_size) {
223 error = EINVAL;
224 break;
225 }
226 savefpu = malloc(data, M_TEMP, M_WAITOK);
227 error = copyin(addr, savefpu, data);
228 if (error == 0)
229 error = fpusetregs(td, (struct savefpu *)savefpu,
230 savefpu + sizeof(struct savefpu), data -
231 sizeof(struct savefpu));
232 free(savefpu, M_TEMP);
233 break;
234
235 default:
236 error = EINVAL;
237 break;
238 }
239
240 return (error);
241 }
242
243 static void
cpu_ptrace_setbase(struct thread * td,int req,register_t r)244 cpu_ptrace_setbase(struct thread *td, int req, register_t r)
245 {
246 struct pcb *pcb;
247
248 pcb = td->td_pcb;
249 set_pcb_flags(pcb, PCB_FULL_IRET);
250 if (req == PT_SETFSBASE) {
251 pcb->pcb_fsbase = r;
252 td->td_frame->tf_fs = _ufssel;
253 } else {
254 pcb->pcb_gsbase = r;
255 td->td_frame->tf_gs = _ugssel;
256 }
257 }
258
259 #ifdef COMPAT_FREEBSD32
260 #define PT_I386_GETXMMREGS (PT_FIRSTMACH + 0)
261 #define PT_I386_SETXMMREGS (PT_FIRSTMACH + 1)
262
263 static int
cpu32_ptrace(struct thread * td,int req,void * addr,int data)264 cpu32_ptrace(struct thread *td, int req, void *addr, int data)
265 {
266 struct savefpu *fpstate;
267 struct pcb *pcb;
268 uint32_t r;
269 int error;
270
271 switch (req) {
272 case PT_I386_GETXMMREGS:
273 fpugetregs(td);
274 error = copyout(get_pcb_user_save_td(td), addr,
275 sizeof(*fpstate));
276 break;
277
278 case PT_I386_SETXMMREGS:
279 fpugetregs(td);
280 fpstate = get_pcb_user_save_td(td);
281 error = copyin(addr, fpstate, sizeof(*fpstate));
282 fpstate->sv_env.en_mxcsr &= cpu_mxcsr_mask;
283 break;
284
285 case PT_GETXSTATE_OLD:
286 case PT_SETXSTATE_OLD:
287 case PT_GETXSTATE_INFO:
288 case PT_GETXSTATE:
289 case PT_SETXSTATE:
290 error = cpu_ptrace_xstate(td, req, addr, data);
291 break;
292
293 case PT_GETFSBASE:
294 case PT_GETGSBASE:
295 if (!SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
296 error = EINVAL;
297 break;
298 }
299 pcb = td->td_pcb;
300 if (td == curthread)
301 update_pcb_bases(pcb);
302 r = req == PT_GETFSBASE ? pcb->pcb_fsbase : pcb->pcb_gsbase;
303 error = copyout(&r, addr, sizeof(r));
304 break;
305
306 case PT_SETFSBASE:
307 case PT_SETGSBASE:
308 if (!SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
309 error = EINVAL;
310 break;
311 }
312 error = copyin(addr, &r, sizeof(r));
313 if (error != 0)
314 break;
315 cpu_ptrace_setbase(td, req, r);
316 break;
317
318 default:
319 error = EINVAL;
320 break;
321 }
322
323 return (error);
324 }
325 #endif
326
327 int
cpu_ptrace(struct thread * td,int req,void * addr,int data)328 cpu_ptrace(struct thread *td, int req, void *addr, int data)
329 {
330 register_t *r, rv;
331 struct pcb *pcb;
332 int error;
333
334 #ifdef COMPAT_FREEBSD32
335 if (SV_CURPROC_FLAG(SV_ILP32))
336 return (cpu32_ptrace(td, req, addr, data));
337 #endif
338
339 /* Support old values of PT_GETXSTATE_OLD and PT_SETXSTATE_OLD. */
340 if (req == PT_FIRSTMACH + 0)
341 req = PT_GETXSTATE_OLD;
342 if (req == PT_FIRSTMACH + 1)
343 req = PT_SETXSTATE_OLD;
344
345 switch (req) {
346 case PT_GETXSTATE_OLD:
347 case PT_SETXSTATE_OLD:
348 case PT_GETXSTATE_INFO:
349 case PT_GETXSTATE:
350 case PT_SETXSTATE:
351 error = cpu_ptrace_xstate(td, req, addr, data);
352 break;
353
354 case PT_GETFSBASE:
355 case PT_GETGSBASE:
356 pcb = td->td_pcb;
357 if (td == curthread)
358 update_pcb_bases(pcb);
359 r = req == PT_GETFSBASE ? &pcb->pcb_fsbase : &pcb->pcb_gsbase;
360 error = copyout(r, addr, sizeof(*r));
361 break;
362
363 case PT_SETFSBASE:
364 case PT_SETGSBASE:
365 error = copyin(addr, &rv, sizeof(rv));
366 if (error != 0)
367 break;
368 if (rv >= td->td_proc->p_sysent->sv_maxuser) {
369 error = EINVAL;
370 break;
371 }
372 cpu_ptrace_setbase(td, req, rv);
373 break;
374
375 default:
376 error = EINVAL;
377 break;
378 }
379
380 return (error);
381 }
382
383 int
ptrace_set_pc(struct thread * td,unsigned long addr)384 ptrace_set_pc(struct thread *td, unsigned long addr)
385 {
386
387 td->td_frame->tf_rip = addr;
388 set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
389 return (0);
390 }
391
392 int
ptrace_single_step(struct thread * td)393 ptrace_single_step(struct thread *td)
394 {
395
396 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
397 if ((td->td_frame->tf_rflags & PSL_T) == 0) {
398 td->td_frame->tf_rflags |= PSL_T;
399 td->td_dbgflags |= TDB_STEP;
400 }
401 return (0);
402 }
403
404 int
ptrace_clear_single_step(struct thread * td)405 ptrace_clear_single_step(struct thread *td)
406 {
407
408 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
409 td->td_frame->tf_rflags &= ~PSL_T;
410 td->td_dbgflags &= ~TDB_STEP;
411 return (0);
412 }
413