xref: /freebsd/sys/amd64/linux/linux_machdep.c (revision 38a52bd3)
1 /*-
2  * Copyright (c) 2004 Tim J. Robbins
3  * Copyright (c) 2002 Doug Rabson
4  * Copyright (c) 2000 Marcel Moolenaar
5  * All rights reserved.
6  * Copyright (c) 2013 Dmitry Chagin <dchagin@FreeBSD.org>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer
13  *    in this position and unchanged.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/param.h>
36 #include <sys/capsicum.h>
37 #include <sys/clock.h>
38 #include <sys/dirent.h>
39 #include <sys/fcntl.h>
40 #include <sys/file.h>
41 #include <sys/filedesc.h>
42 #include <sys/kernel.h>
43 #include <sys/ktr.h>
44 #include <sys/limits.h>
45 #include <sys/lock.h>
46 #include <sys/malloc.h>
47 #include <sys/mman.h>
48 #include <sys/mutex.h>
49 #include <sys/priv.h>
50 #include <sys/proc.h>
51 #include <sys/ptrace.h>
52 #include <sys/resource.h>
53 #include <sys/resourcevar.h>
54 #include <sys/sched.h>
55 #include <sys/syscallsubr.h>
56 #include <sys/sysproto.h>
57 #include <sys/systm.h>
58 #include <sys/unistd.h>
59 #include <sys/vnode.h>
60 #include <sys/wait.h>
61 
62 #include <security/mac/mac_framework.h>
63 
64 #include <ufs/ufs/extattr.h>
65 #include <ufs/ufs/quota.h>
66 #include <ufs/ufs/ufsmount.h>
67 
68 #include <machine/frame.h>
69 #include <machine/md_var.h>
70 #include <machine/pcb.h>
71 #include <machine/psl.h>
72 #include <machine/segments.h>
73 #include <machine/specialreg.h>
74 
75 #include <vm/pmap.h>
76 #include <vm/vm.h>
77 #include <vm/vm_extern.h>
78 #include <vm/vm_kern.h>
79 #include <vm/vm_map.h>
80 
81 #include <x86/ifunc.h>
82 #include <x86/reg.h>
83 #include <x86/sysarch.h>
84 
85 #include <amd64/linux/linux.h>
86 #include <amd64/linux/linux_proto.h>
87 #include <compat/linux/linux_emul.h>
88 #include <compat/linux/linux_file.h>
89 #include <compat/linux/linux_fork.h>
90 #include <compat/linux/linux_ipc.h>
91 #include <compat/linux/linux_misc.h>
92 #include <compat/linux/linux_mmap.h>
93 #include <compat/linux/linux_signal.h>
94 #include <compat/linux/linux_util.h>
95 
96 #define	LINUX_ARCH_AMD64		0xc000003e
97 
98 int
99 linux_set_upcall(struct thread *td, register_t stack)
100 {
101 
102 	if (stack)
103 		td->td_frame->tf_rsp = stack;
104 
105 	/*
106 	 * The newly created Linux thread returns
107 	 * to the user space by the same path that a parent does.
108 	 */
109 	td->td_frame->tf_rax = 0;
110 	return (0);
111 }
112 
113 int
114 linux_mmap2(struct thread *td, struct linux_mmap2_args *args)
115 {
116 
117 	return (linux_mmap_common(td, args->addr, args->len, args->prot,
118 		args->flags, args->fd, args->pgoff));
119 }
120 
121 int
122 linux_mprotect(struct thread *td, struct linux_mprotect_args *uap)
123 {
124 
125 	return (linux_mprotect_common(td, uap->addr, uap->len, uap->prot));
126 }
127 
128 int
129 linux_madvise(struct thread *td, struct linux_madvise_args *uap)
130 {
131 
132 	return (linux_madvise_common(td, uap->addr, uap->len, uap->behav));
133 }
134 
135 int
136 linux_iopl(struct thread *td, struct linux_iopl_args *args)
137 {
138 	int error;
139 
140 	LINUX_CTR(iopl);
141 
142 	if (args->level > 3)
143 		return (EINVAL);
144 	if ((error = priv_check(td, PRIV_IO)) != 0)
145 		return (error);
146 	if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
147 		return (error);
148 	td->td_frame->tf_rflags = (td->td_frame->tf_rflags & ~PSL_IOPL) |
149 	    (args->level * (PSL_IOPL / 3));
150 
151 	return (0);
152 }
153 
154 int
155 linux_pause(struct thread *td, struct linux_pause_args *args)
156 {
157 	struct proc *p = td->td_proc;
158 	sigset_t sigmask;
159 
160 	LINUX_CTR(pause);
161 
162 	PROC_LOCK(p);
163 	sigmask = td->td_sigmask;
164 	PROC_UNLOCK(p);
165 	return (kern_sigsuspend(td, sigmask));
166 }
167 
168 int
169 linux_arch_prctl(struct thread *td, struct linux_arch_prctl_args *args)
170 {
171 	unsigned long long cet[3];
172 	struct pcb *pcb;
173 	int error;
174 
175 	pcb = td->td_pcb;
176 	LINUX_CTR2(arch_prctl, "0x%x, %p", args->code, args->addr);
177 
178 	switch (args->code) {
179 	case LINUX_ARCH_SET_GS:
180 		if (args->addr < VM_MAXUSER_ADDRESS) {
181 			update_pcb_bases(pcb);
182 			pcb->pcb_gsbase = args->addr;
183 			td->td_frame->tf_gs = _ugssel;
184 			error = 0;
185 		} else
186 			error = EPERM;
187 		break;
188 	case LINUX_ARCH_SET_FS:
189 		if (args->addr < VM_MAXUSER_ADDRESS) {
190 			update_pcb_bases(pcb);
191 			pcb->pcb_fsbase = args->addr;
192 			td->td_frame->tf_fs = _ufssel;
193 			error = 0;
194 		} else
195 			error = EPERM;
196 		break;
197 	case LINUX_ARCH_GET_FS:
198 		error = copyout(&pcb->pcb_fsbase, PTRIN(args->addr),
199 		    sizeof(args->addr));
200 		break;
201 	case LINUX_ARCH_GET_GS:
202 		error = copyout(&pcb->pcb_gsbase, PTRIN(args->addr),
203 		    sizeof(args->addr));
204 		break;
205 	case LINUX_ARCH_CET_STATUS:
206 		memset(cet, 0, sizeof(cet));
207 		error = copyout(&cet, PTRIN(args->addr), sizeof(cet));
208 		break;
209 	default:
210 		linux_msg(td, "unsupported arch_prctl code %#x", args->code);
211 		error = EINVAL;
212 	}
213 	return (error);
214 }
215 
216 int
217 linux_set_cloned_tls(struct thread *td, void *desc)
218 {
219 	struct pcb *pcb;
220 
221 	if ((uint64_t)desc >= VM_MAXUSER_ADDRESS)
222 		return (EPERM);
223 
224 	pcb = td->td_pcb;
225 	update_pcb_bases(pcb);
226 	pcb->pcb_fsbase = (register_t)desc;
227 	td->td_frame->tf_fs = _ufssel;
228 
229 	return (0);
230 }
231 
232 int futex_xchgl_nosmap(int oparg, uint32_t *uaddr, int *oldval);
233 int futex_xchgl_smap(int oparg, uint32_t *uaddr, int *oldval);
234 DEFINE_IFUNC(, int, futex_xchgl, (int, uint32_t *, int *))
235 {
236 
237 	return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ?
238 	    futex_xchgl_smap : futex_xchgl_nosmap);
239 }
240 
241 int futex_addl_nosmap(int oparg, uint32_t *uaddr, int *oldval);
242 int futex_addl_smap(int oparg, uint32_t *uaddr, int *oldval);
243 DEFINE_IFUNC(, int, futex_addl, (int, uint32_t *, int *))
244 {
245 
246 	return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ?
247 	    futex_addl_smap : futex_addl_nosmap);
248 }
249 
250 int futex_orl_nosmap(int oparg, uint32_t *uaddr, int *oldval);
251 int futex_orl_smap(int oparg, uint32_t *uaddr, int *oldval);
252 DEFINE_IFUNC(, int, futex_orl, (int, uint32_t *, int *))
253 {
254 
255 	return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ?
256 	    futex_orl_smap : futex_orl_nosmap);
257 }
258 
259 int futex_andl_nosmap(int oparg, uint32_t *uaddr, int *oldval);
260 int futex_andl_smap(int oparg, uint32_t *uaddr, int *oldval);
261 DEFINE_IFUNC(, int, futex_andl, (int, uint32_t *, int *))
262 {
263 
264 	return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ?
265 	    futex_andl_smap : futex_andl_nosmap);
266 }
267 
268 int futex_xorl_nosmap(int oparg, uint32_t *uaddr, int *oldval);
269 int futex_xorl_smap(int oparg, uint32_t *uaddr, int *oldval);
270 DEFINE_IFUNC(, int, futex_xorl, (int, uint32_t *, int *))
271 {
272 
273 	return ((cpu_stdext_feature & CPUID_STDEXT_SMAP) != 0 ?
274 	    futex_xorl_smap : futex_xorl_nosmap);
275 }
276 
277 void
278 bsd_to_linux_regset(const struct reg *b_reg, struct linux_pt_regset *l_regset)
279 {
280 
281 	l_regset->r15 = b_reg->r_r15;
282 	l_regset->r14 = b_reg->r_r14;
283 	l_regset->r13 = b_reg->r_r13;
284 	l_regset->r12 = b_reg->r_r12;
285 	l_regset->rbp = b_reg->r_rbp;
286 	l_regset->rbx = b_reg->r_rbx;
287 	l_regset->r11 = b_reg->r_r11;
288 	l_regset->r10 = b_reg->r_r10;
289 	l_regset->r9 = b_reg->r_r9;
290 	l_regset->r8 = b_reg->r_r8;
291 	l_regset->rax = b_reg->r_rax;
292 	l_regset->rcx = b_reg->r_rcx;
293 	l_regset->rdx = b_reg->r_rdx;
294 	l_regset->rsi = b_reg->r_rsi;
295 	l_regset->rdi = b_reg->r_rdi;
296 	l_regset->orig_rax = b_reg->r_rax;
297 	l_regset->rip = b_reg->r_rip;
298 	l_regset->cs = b_reg->r_cs;
299 	l_regset->eflags = b_reg->r_rflags;
300 	l_regset->rsp = b_reg->r_rsp;
301 	l_regset->ss = b_reg->r_ss;
302 	l_regset->fs_base = 0;
303 	l_regset->gs_base = 0;
304 	l_regset->ds = b_reg->r_ds;
305 	l_regset->es = b_reg->r_es;
306 	l_regset->fs = b_reg->r_fs;
307 	l_regset->gs = b_reg->r_gs;
308 }
309 
310 void
311 linux_to_bsd_regset(struct reg *b_reg, const struct linux_pt_regset *l_regset)
312 {
313 
314 	b_reg->r_r15 = l_regset->r15;
315 	b_reg->r_r14 = l_regset->r14;
316 	b_reg->r_r13 = l_regset->r13;
317 	b_reg->r_r12 = l_regset->r12;
318 	b_reg->r_rbp = l_regset->rbp;
319 	b_reg->r_rbx = l_regset->rbx;
320 	b_reg->r_r11 = l_regset->r11;
321 	b_reg->r_r10 = l_regset->r10;
322 	b_reg->r_r9 = l_regset->r9;
323 	b_reg->r_r8 = l_regset->r8;
324 	b_reg->r_rax = l_regset->rax;
325 	b_reg->r_rcx = l_regset->rcx;
326 	b_reg->r_rdx = l_regset->rdx;
327 	b_reg->r_rsi = l_regset->rsi;
328 	b_reg->r_rdi = l_regset->rdi;
329 	b_reg->r_rax = l_regset->orig_rax;
330 	b_reg->r_rip = l_regset->rip;
331 	b_reg->r_cs = l_regset->cs;
332 	b_reg->r_rflags = l_regset->eflags;
333 	b_reg->r_rsp = l_regset->rsp;
334 	b_reg->r_ss = l_regset->ss;
335 	b_reg->r_ds = l_regset->ds;
336 	b_reg->r_es = l_regset->es;
337 	b_reg->r_fs = l_regset->fs;
338 	b_reg->r_gs = l_regset->gs;
339 }
340 
341 void
342 linux_ptrace_get_syscall_info_machdep(const struct reg *reg,
343     struct syscall_info *si)
344 {
345 
346 	si->arch = LINUX_ARCH_AMD64;
347 	si->instruction_pointer = reg->r_rip;
348 	si->stack_pointer = reg->r_rsp;
349 }
350 
351 int
352 linux_ptrace_getregs_machdep(struct thread *td, pid_t pid,
353     struct linux_pt_regset *l_regset)
354 {
355 	struct ptrace_lwpinfo lwpinfo;
356 	struct pcb *pcb;
357 	int error;
358 
359 	pcb = td->td_pcb;
360 	if (td == curthread)
361 		update_pcb_bases(pcb);
362 
363 	l_regset->fs_base = pcb->pcb_fsbase;
364 	l_regset->gs_base = pcb->pcb_gsbase;
365 
366 	error = kern_ptrace(td, PT_LWPINFO, pid, &lwpinfo, sizeof(lwpinfo));
367 	if (error != 0) {
368 		linux_msg(td, "PT_LWPINFO failed with error %d", error);
369 		return (error);
370 	}
371 	if ((lwpinfo.pl_flags & PL_FLAG_SCE) != 0) {
372 		/*
373 		 * Undo the mangling done in exception.S:fast_syscall_common().
374 		 */
375 		l_regset->r10 = l_regset->rcx;
376 	}
377 	if ((lwpinfo.pl_flags & (PL_FLAG_SCE | PL_FLAG_SCX)) != 0) {
378 		/*
379 		 * In Linux, the syscall number - passed to the syscall
380 		 * as rax - is preserved in orig_rax; rax gets overwritten
381 		 * with syscall return value.
382 		 */
383 		l_regset->orig_rax = lwpinfo.pl_syscall_code;
384 	}
385 
386 	return (0);
387 }
388