xref: /freebsd/sys/amd64/amd64/ptrace_machdep.c (revision 780fb4a2)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/malloc.h>
36 #include <sys/proc.h>
37 #include <sys/ptrace.h>
38 #include <sys/sysent.h>
39 #include <vm/vm.h>
40 #include <vm/pmap.h>
41 #include <machine/md_var.h>
42 #include <machine/pcb.h>
43 #include <machine/frame.h>
44 #include <machine/vmparam.h>
45 
46 #ifdef COMPAT_FREEBSD32
47 struct ptrace_xstate_info32 {
48 	uint32_t	xsave_mask1, xsave_mask2;
49 	uint32_t	xsave_len;
50 };
51 #endif
52 
53 static int
54 cpu_ptrace_xstate(struct thread *td, int req, void *addr, int data)
55 {
56 	struct ptrace_xstate_info info;
57 #ifdef COMPAT_FREEBSD32
58 	struct ptrace_xstate_info32 info32;
59 #endif
60 	char *savefpu;
61 	int error;
62 
63 	if (!use_xsave)
64 		return (EOPNOTSUPP);
65 
66 	switch (req) {
67 	case PT_GETXSTATE_OLD:
68 		fpugetregs(td);
69 		savefpu = (char *)(get_pcb_user_save_td(td) + 1);
70 		error = copyout(savefpu, addr,
71 		    cpu_max_ext_state_size - sizeof(struct savefpu));
72 		break;
73 
74 	case PT_SETXSTATE_OLD:
75 		if (data > cpu_max_ext_state_size - sizeof(struct savefpu)) {
76 			error = EINVAL;
77 			break;
78 		}
79 		savefpu = malloc(data, M_TEMP, M_WAITOK);
80 		error = copyin(addr, savefpu, data);
81 		if (error == 0) {
82 			fpugetregs(td);
83 			error = fpusetxstate(td, savefpu, data);
84 		}
85 		free(savefpu, M_TEMP);
86 		break;
87 
88 	case PT_GETXSTATE_INFO:
89 #ifdef COMPAT_FREEBSD32
90 		if (SV_CURPROC_FLAG(SV_ILP32)) {
91 			if (data != sizeof(info32)) {
92 				error = EINVAL;
93 			} else {
94 				info32.xsave_len = cpu_max_ext_state_size;
95 				info32.xsave_mask1 = xsave_mask;
96 				info32.xsave_mask2 = xsave_mask >> 32;
97 				error = copyout(&info32, addr, data);
98 			}
99 		} else
100 #endif
101 		{
102 			if (data != sizeof(info)) {
103 				error  = EINVAL;
104 			} else {
105 				bzero(&info, sizeof(info));
106 				info.xsave_len = cpu_max_ext_state_size;
107 				info.xsave_mask = xsave_mask;
108 				error = copyout(&info, addr, data);
109 			}
110 		}
111 		break;
112 
113 	case PT_GETXSTATE:
114 		fpugetregs(td);
115 		savefpu = (char *)(get_pcb_user_save_td(td));
116 		error = copyout(savefpu, addr, cpu_max_ext_state_size);
117 		break;
118 
119 	case PT_SETXSTATE:
120 		if (data < sizeof(struct savefpu) ||
121 		    data > cpu_max_ext_state_size) {
122 			error = EINVAL;
123 			break;
124 		}
125 		savefpu = malloc(data, M_TEMP, M_WAITOK);
126 		error = copyin(addr, savefpu, data);
127 		if (error == 0)
128 			error = fpusetregs(td, (struct savefpu *)savefpu,
129 			    savefpu + sizeof(struct savefpu), data -
130 			    sizeof(struct savefpu));
131 		free(savefpu, M_TEMP);
132 		break;
133 
134 	default:
135 		error = EINVAL;
136 		break;
137 	}
138 
139 	return (error);
140 }
141 
142 static void
143 cpu_ptrace_setbase(struct thread *td, int req, register_t r)
144 {
145 	struct pcb *pcb;
146 
147 	pcb = td->td_pcb;
148 	set_pcb_flags(pcb, PCB_FULL_IRET);
149 	if (req == PT_SETFSBASE) {
150 		pcb->pcb_fsbase = r;
151 		td->td_frame->tf_fs = _ufssel;
152 	} else {
153 		pcb->pcb_gsbase = r;
154 		td->td_frame->tf_gs = _ugssel;
155 	}
156 }
157 
158 #ifdef COMPAT_FREEBSD32
159 #define PT_I386_GETXMMREGS	(PT_FIRSTMACH + 0)
160 #define PT_I386_SETXMMREGS	(PT_FIRSTMACH + 1)
161 
162 static int
163 cpu32_ptrace(struct thread *td, int req, void *addr, int data)
164 {
165 	struct savefpu *fpstate;
166 	struct pcb *pcb;
167 	uint32_t r;
168 	int error;
169 
170 	switch (req) {
171 	case PT_I386_GETXMMREGS:
172 		fpugetregs(td);
173 		error = copyout(get_pcb_user_save_td(td), addr,
174 		    sizeof(*fpstate));
175 		break;
176 
177 	case PT_I386_SETXMMREGS:
178 		fpugetregs(td);
179 		fpstate = get_pcb_user_save_td(td);
180 		error = copyin(addr, fpstate, sizeof(*fpstate));
181 		fpstate->sv_env.en_mxcsr &= cpu_mxcsr_mask;
182 		break;
183 
184 	case PT_GETXSTATE_OLD:
185 	case PT_SETXSTATE_OLD:
186 	case PT_GETXSTATE_INFO:
187 	case PT_GETXSTATE:
188 	case PT_SETXSTATE:
189 		error = cpu_ptrace_xstate(td, req, addr, data);
190 		break;
191 
192 	case PT_GETFSBASE:
193 	case PT_GETGSBASE:
194 		if (!SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
195 			error = EINVAL;
196 			break;
197 		}
198 		pcb = td->td_pcb;
199 		if (td == curthread)
200 			update_pcb_bases(pcb);
201 		r = req == PT_GETFSBASE ? pcb->pcb_fsbase : pcb->pcb_gsbase;
202 		error = copyout(&r, addr, sizeof(r));
203 		break;
204 
205 	case PT_SETFSBASE:
206 	case PT_SETGSBASE:
207 		if (!SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
208 			error = EINVAL;
209 			break;
210 		}
211 		error = copyin(addr, &r, sizeof(r));
212 		if (error != 0)
213 			break;
214 		cpu_ptrace_setbase(td, req, r);
215 		break;
216 
217 	default:
218 		error = EINVAL;
219 		break;
220 	}
221 
222 	return (error);
223 }
224 #endif
225 
226 int
227 cpu_ptrace(struct thread *td, int req, void *addr, int data)
228 {
229 	register_t *r, rv;
230 	struct pcb *pcb;
231 	int error;
232 
233 #ifdef COMPAT_FREEBSD32
234 	if (SV_CURPROC_FLAG(SV_ILP32))
235 		return (cpu32_ptrace(td, req, addr, data));
236 #endif
237 
238 	/* Support old values of PT_GETXSTATE_OLD and PT_SETXSTATE_OLD. */
239 	if (req == PT_FIRSTMACH + 0)
240 		req = PT_GETXSTATE_OLD;
241 	if (req == PT_FIRSTMACH + 1)
242 		req = PT_SETXSTATE_OLD;
243 
244 	switch (req) {
245 	case PT_GETXSTATE_OLD:
246 	case PT_SETXSTATE_OLD:
247 	case PT_GETXSTATE_INFO:
248 	case PT_GETXSTATE:
249 	case PT_SETXSTATE:
250 		error = cpu_ptrace_xstate(td, req, addr, data);
251 		break;
252 
253 	case PT_GETFSBASE:
254 	case PT_GETGSBASE:
255 		pcb = td->td_pcb;
256 		if (td == curthread)
257 			update_pcb_bases(pcb);
258 		r = req == PT_GETFSBASE ? &pcb->pcb_fsbase : &pcb->pcb_gsbase;
259 		error = copyout(r, addr, sizeof(*r));
260 		break;
261 
262 	case PT_SETFSBASE:
263 	case PT_SETGSBASE:
264 		error = copyin(addr, &rv, sizeof(rv));
265 		if (error != 0)
266 			break;
267 		if (rv >= td->td_proc->p_sysent->sv_maxuser) {
268 			error = EINVAL;
269 			break;
270 		}
271 		cpu_ptrace_setbase(td, req, rv);
272 		break;
273 
274 	default:
275 		error = EINVAL;
276 		break;
277 	}
278 
279 	return (error);
280 }
281