1/*-
2 * Copyright (c) 2013 Dmitry Chagin
3 * Copyright (c) 2004 Tim J. Robbins
4 * Copyright (c) 2003 Peter Wemm
5 * Copyright (c) 2002 Doug Rabson
6 * Copyright (c) 1998-1999 Andrew Gallatin
7 * Copyright (c) 1994-1996 S��ren Schmidt
8 * All rights reserved.
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 *    in this position and unchanged.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. The name of the author may not be used to endorse or promote products
20 *    derived from this software without specific prior written permission
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD$");
36
37#define	__ELF_WORD_SIZE	64
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/exec.h>
42#include <sys/fcntl.h>
43#include <sys/imgact.h>
44#include <sys/imgact_elf.h>
45#include <sys/kernel.h>
46#include <sys/ktr.h>
47#include <sys/lock.h>
48#include <sys/malloc.h>
49#include <sys/module.h>
50#include <sys/mutex.h>
51#include <sys/proc.h>
52#include <sys/resourcevar.h>
53#include <sys/signalvar.h>
54#include <sys/syscallsubr.h>
55#include <sys/sysctl.h>
56#include <sys/sysent.h>
57#include <sys/sysproto.h>
58#include <sys/vnode.h>
59#include <sys/eventhandler.h>
60
61#include <vm/vm.h>
62#include <vm/pmap.h>
63#include <vm/vm_extern.h>
64#include <vm/vm_map.h>
65#include <vm/vm_object.h>
66#include <vm/vm_page.h>
67#include <vm/vm_param.h>
68
69#include <machine/cpu.h>
70#include <machine/md_var.h>
71#include <machine/pcb.h>
72#include <machine/specialreg.h>
73#include <machine/trap.h>
74
75#include <amd64/linux/linux.h>
76#include <amd64/linux/linux_proto.h>
77#include <compat/linux/linux_emul.h>
78#include <compat/linux/linux_ioctl.h>
79#include <compat/linux/linux_mib.h>
80#include <compat/linux/linux_misc.h>
81#include <compat/linux/linux_signal.h>
82#include <compat/linux/linux_sysproto.h>
83#include <compat/linux/linux_util.h>
84#include <compat/linux/linux_vdso.h>
85
86MODULE_VERSION(linux64, 1);
87
88const char *linux_kplatform;
89static int linux_szsigcode;
90static vm_object_t linux_shared_page_obj;
91static char *linux_shared_page_mapping;
92extern char _binary_linux_locore_o_start;
93extern char _binary_linux_locore_o_end;
94
95extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL];
96
97SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler);
98
99static int	linux_copyout_strings(struct image_params *imgp,
100		    uintptr_t *stack_base);
101static int	linux_fixup_elf(uintptr_t *stack_base,
102		    struct image_params *iparams);
103static bool	linux_trans_osrel(const Elf_Note *note, int32_t *osrel);
104static void	linux_vdso_install(void *param);
105static void	linux_vdso_deinstall(void *param);
106static void	linux_set_syscall_retval(struct thread *td, int error);
107static int	linux_fetch_syscall_args(struct thread *td);
108static void	linux_exec_setregs(struct thread *td, struct image_params *imgp,
109		    uintptr_t stack);
110static int	linux_vsyscall(struct thread *td);
111
112#define LINUX_T_UNKNOWN  255
113static int _bsd_to_linux_trapcode[] = {
114	LINUX_T_UNKNOWN,	/* 0 */
115	6,			/* 1  T_PRIVINFLT */
116	LINUX_T_UNKNOWN,	/* 2 */
117	3,			/* 3  T_BPTFLT */
118	LINUX_T_UNKNOWN,	/* 4 */
119	LINUX_T_UNKNOWN,	/* 5 */
120	16,			/* 6  T_ARITHTRAP */
121	254,			/* 7  T_ASTFLT */
122	LINUX_T_UNKNOWN,	/* 8 */
123	13,			/* 9  T_PROTFLT */
124	1,			/* 10 T_TRCTRAP */
125	LINUX_T_UNKNOWN,	/* 11 */
126	14,			/* 12 T_PAGEFLT */
127	LINUX_T_UNKNOWN,	/* 13 */
128	17,			/* 14 T_ALIGNFLT */
129	LINUX_T_UNKNOWN,	/* 15 */
130	LINUX_T_UNKNOWN,	/* 16 */
131	LINUX_T_UNKNOWN,	/* 17 */
132	0,			/* 18 T_DIVIDE */
133	2,			/* 19 T_NMI */
134	4,			/* 20 T_OFLOW */
135	5,			/* 21 T_BOUND */
136	7,			/* 22 T_DNA */
137	8,			/* 23 T_DOUBLEFLT */
138	9,			/* 24 T_FPOPFLT */
139	10,			/* 25 T_TSSFLT */
140	11,			/* 26 T_SEGNPFLT */
141	12,			/* 27 T_STKFLT */
142	18,			/* 28 T_MCHK */
143	19,			/* 29 T_XMMFLT */
144	15			/* 30 T_RESERVED */
145};
146#define bsd_to_linux_trapcode(code) \
147    ((code)<nitems(_bsd_to_linux_trapcode)? \
148     _bsd_to_linux_trapcode[(code)]: \
149     LINUX_T_UNKNOWN)
150
151LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode);
152LINUX_VDSO_SYM_CHAR(linux_platform);
153
154/*
155 * If FreeBSD & Linux have a difference of opinion about what a trap
156 * means, deal with it here.
157 *
158 * MPSAFE
159 */
160static int
161linux_translate_traps(int signal, int trap_code)
162{
163
164	if (signal != SIGBUS)
165		return (signal);
166	switch (trap_code) {
167	case T_PROTFLT:
168	case T_TSSFLT:
169	case T_DOUBLEFLT:
170	case T_PAGEFLT:
171		return (SIGSEGV);
172	default:
173		return (signal);
174	}
175}
176
177static int
178linux_fetch_syscall_args(struct thread *td)
179{
180	struct proc *p;
181	struct trapframe *frame;
182	struct syscall_args *sa;
183
184	p = td->td_proc;
185	frame = td->td_frame;
186	sa = &td->td_sa;
187
188	sa->args[0] = frame->tf_rdi;
189	sa->args[1] = frame->tf_rsi;
190	sa->args[2] = frame->tf_rdx;
191	sa->args[3] = frame->tf_rcx;
192	sa->args[4] = frame->tf_r8;
193	sa->args[5] = frame->tf_r9;
194	sa->code = frame->tf_rax;
195
196	if (sa->code >= p->p_sysent->sv_size)
197		/* nosys */
198		sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1];
199	else
200		sa->callp = &p->p_sysent->sv_table[sa->code];
201
202	td->td_retval[0] = 0;
203	return (0);
204}
205
206static void
207linux_set_syscall_retval(struct thread *td, int error)
208{
209	struct trapframe *frame;
210
211	frame = td->td_frame;
212
213	switch (error) {
214	case 0:
215		frame->tf_rax = td->td_retval[0];
216 		frame->tf_r10 = frame->tf_rcx;
217		break;
218
219	case ERESTART:
220		/*
221		 * Reconstruct pc, we know that 'syscall' is 2 bytes,
222		 * lcall $X,y is 7 bytes, int 0x80 is 2 bytes.
223		 * We saved this in tf_err.
224		 *
225		 */
226		frame->tf_rip -= frame->tf_err;
227		frame->tf_r10 = frame->tf_rcx;
228		break;
229
230	case EJUSTRETURN:
231		break;
232
233	default:
234		frame->tf_rax = bsd_to_linux_errno(error);
235		frame->tf_r10 = frame->tf_rcx;
236		break;
237	}
238
239	/*
240	 * Differently from FreeBSD native ABI, on Linux only %rcx
241	 * and %r11 values are not preserved across the syscall.
242	 * Require full context restore to get all registers except
243	 * those two restored at return to usermode.
244	 *
245	 * XXX: Would be great to be able to avoid PCB_FULL_IRET
246	 *      for the error == 0 case.
247	 */
248	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
249}
250
251static int
252linux_copyout_auxargs(struct image_params *imgp, uintptr_t base)
253{
254	Elf_Auxargs *args;
255	Elf_Auxinfo *argarray, *pos;
256	struct proc *p;
257	int error, issetugid;
258
259	p = imgp->proc;
260	args = (Elf64_Auxargs *)imgp->auxargs;
261	argarray = pos = malloc(LINUX_AT_COUNT * sizeof(*pos), M_TEMP,
262	    M_WAITOK | M_ZERO);
263
264	issetugid = p->p_flag & P_SUGID ? 1 : 0;
265	AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR,
266	    imgp->proc->p_sysent->sv_shared_page_base);
267	AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature);
268	AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz);
269	AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
270	AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
271	AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
272	AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz);
273	AUXARGS_ENTRY(pos, AT_BASE, args->base);
274	AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
275	AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
276	AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid);
277	AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid);
278	AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid);
279	AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid);
280	AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid);
281	AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform));
282	AUXARGS_ENTRY_PTR(pos, LINUX_AT_RANDOM, imgp->canary);
283	if (imgp->execpathp != 0)
284		AUXARGS_ENTRY_PTR(pos, LINUX_AT_EXECFN, imgp->execpathp);
285	if (args->execfd != -1)
286		AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
287	AUXARGS_ENTRY(pos, AT_NULL, 0);
288
289	free(imgp->auxargs, M_TEMP);
290	imgp->auxargs = NULL;
291	KASSERT(pos - argarray <= LINUX_AT_COUNT, ("Too many auxargs"));
292
293	error = copyout(argarray, (void *)base,
294	    sizeof(*argarray) * LINUX_AT_COUNT);
295	free(argarray, M_TEMP);
296	return (error);
297}
298
299static int
300linux_fixup_elf(uintptr_t *stack_base, struct image_params *imgp)
301{
302	Elf_Addr *base;
303
304	base = (Elf64_Addr *)*stack_base;
305	base--;
306	if (suword(base, (uint64_t)imgp->args->argc) == -1)
307		return (EFAULT);
308
309	*stack_base = (uintptr_t)base;
310	return (0);
311}
312
313/*
314 * Copy strings out to the new process address space, constructing new arg
315 * and env vector tables. Return a pointer to the base so that it can be used
316 * as the initial stack pointer.
317 */
318static int
319linux_copyout_strings(struct image_params *imgp, uintptr_t *stack_base)
320{
321	int argc, envc, error;
322	char **vectp;
323	char *stringp;
324	uintptr_t destp, ustringp;
325	struct ps_strings *arginfo;
326	char canary[LINUX_AT_RANDOM_LEN];
327	size_t execpath_len;
328	struct proc *p;
329
330	/* Calculate string base and vector table pointers. */
331	if (imgp->execpath != NULL && imgp->auxargs != NULL)
332		execpath_len = strlen(imgp->execpath) + 1;
333	else
334		execpath_len = 0;
335
336	p = imgp->proc;
337	arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings;
338	destp = (uintptr_t)arginfo;
339
340	if (execpath_len != 0) {
341		destp -= execpath_len;
342		destp = rounddown2(destp, sizeof(void *));
343		imgp->execpathp = (void *)destp;
344		error = copyout(imgp->execpath, imgp->execpathp, execpath_len);
345		if (error != 0)
346			return (error);
347	}
348
349	/* Prepare the canary for SSP. */
350	arc4rand(canary, sizeof(canary), 0);
351	destp -= roundup(sizeof(canary), sizeof(void *));
352	imgp->canary = (void *)destp;
353	error = copyout(canary, imgp->canary, sizeof(canary));
354	if (error != 0)
355		return (error);
356
357	/* Allocate room for the argument and environment strings. */
358	destp -= ARG_MAX - imgp->args->stringspace;
359	destp = rounddown2(destp, sizeof(void *));
360	ustringp = destp;
361
362	if (imgp->auxargs) {
363		/*
364		 * Allocate room on the stack for the ELF auxargs
365		 * array.  It has LINUX_AT_COUNT entries.
366		 */
367		destp -= LINUX_AT_COUNT * sizeof(Elf64_Auxinfo);
368		destp = rounddown2(destp, sizeof(void *));
369	}
370
371	vectp = (char **)destp;
372
373	/*
374	 * Allocate room for the argv[] and env vectors including the
375	 * terminating NULL pointers.
376	 */
377	vectp -= imgp->args->argc + 1 + imgp->args->envc + 1;
378
379	/*
380	 * Starting with 2.24, glibc depends on a 16-byte stack alignment.
381	 * One "long argc" will be prepended later.
382	 */
383	vectp = (char **)((((uintptr_t)vectp + 8) & ~0xF) - 8);
384
385	/* vectp also becomes our initial stack base. */
386	*stack_base = (uintptr_t)vectp;
387
388	stringp = imgp->args->begin_argv;
389	argc = imgp->args->argc;
390	envc = imgp->args->envc;
391
392	/* Copy out strings - arguments and environment. */
393	error = copyout(stringp, (void *)ustringp,
394	    ARG_MAX - imgp->args->stringspace);
395	if (error != 0)
396		return (error);
397
398	/* Fill in "ps_strings" struct for ps, w, etc. */
399	if (suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp) != 0 ||
400	    suword(&arginfo->ps_nargvstr, argc) != 0)
401		return (EFAULT);
402
403	/* Fill in argument portion of vector table. */
404	for (; argc > 0; --argc) {
405		if (suword(vectp++, ustringp) != 0)
406			return (EFAULT);
407		while (*stringp++ != 0)
408			ustringp++;
409		ustringp++;
410	}
411
412	/* A null vector table pointer separates the argp's from the envp's. */
413	if (suword(vectp++, 0) != 0)
414		return (EFAULT);
415
416	if (suword(&arginfo->ps_envstr, (long)(intptr_t)vectp) != 0 ||
417	    suword(&arginfo->ps_nenvstr, envc) != 0)
418		return (EFAULT);
419
420	/* Fill in environment portion of vector table. */
421	for (; envc > 0; --envc) {
422		if (suword(vectp++, ustringp) != 0)
423			return (EFAULT);
424		while (*stringp++ != 0)
425			ustringp++;
426		ustringp++;
427	}
428
429	/* The end of the vector table is a null pointer. */
430	if (suword(vectp, 0) != 0)
431		return (EFAULT);
432
433	if (imgp->auxargs) {
434		vectp++;
435		error = imgp->sysent->sv_copyout_auxargs(imgp,
436		    (uintptr_t)vectp);
437		if (error != 0)
438			return (error);
439	}
440
441	return (0);
442}
443
444/*
445 * Reset registers to default values on exec.
446 */
447static void
448linux_exec_setregs(struct thread *td, struct image_params *imgp,
449    uintptr_t stack)
450{
451	struct trapframe *regs;
452	struct pcb *pcb;
453	register_t saved_rflags;
454
455	regs = td->td_frame;
456	pcb = td->td_pcb;
457
458	if (td->td_proc->p_md.md_ldt != NULL)
459		user_ldt_free(td);
460
461	pcb->pcb_fsbase = 0;
462	pcb->pcb_gsbase = 0;
463	clear_pcb_flags(pcb, PCB_32BIT);
464	pcb->pcb_initial_fpucw = __LINUX_NPXCW__;
465	set_pcb_flags(pcb, PCB_FULL_IRET);
466
467	saved_rflags = regs->tf_rflags & PSL_T;
468	bzero((char *)regs, sizeof(struct trapframe));
469	regs->tf_rip = imgp->entry_addr;
470	regs->tf_rsp = stack;
471	regs->tf_rflags = PSL_USER | saved_rflags;
472	regs->tf_ss = _udatasel;
473	regs->tf_cs = _ucodesel;
474	regs->tf_ds = _udatasel;
475	regs->tf_es = _udatasel;
476	regs->tf_fs = _ufssel;
477	regs->tf_gs = _ugssel;
478	regs->tf_flags = TF_HASSEGS;
479
480	x86_clear_dbregs(pcb);
481
482	/*
483	 * Drop the FP state if we hold it, so that the process gets a
484	 * clean FP state if it uses the FPU again.
485	 */
486	fpstate_drop(td);
487}
488
489/*
490 * Copied from amd64/amd64/machdep.c
491 *
492 * XXX fpu state need? don't think so
493 */
494int
495linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args)
496{
497	struct proc *p;
498	struct l_ucontext uc;
499	struct l_sigcontext *context;
500	struct trapframe *regs;
501	unsigned long rflags;
502	int error;
503	ksiginfo_t ksi;
504
505	regs = td->td_frame;
506	error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc));
507	if (error != 0)
508		return (error);
509
510	p = td->td_proc;
511	context = &uc.uc_mcontext;
512	rflags = context->sc_rflags;
513
514	/*
515	 * Don't allow users to change privileged or reserved flags.
516	 */
517	/*
518	 * XXX do allow users to change the privileged flag PSL_RF.
519	 * The cpu sets PSL_RF in tf_rflags for faults.  Debuggers
520	 * should sometimes set it there too.  tf_rflags is kept in
521	 * the signal context during signal handling and there is no
522	 * other place to remember it, so the PSL_RF bit may be
523	 * corrupted by the signal handler without us knowing.
524	 * Corruption of the PSL_RF bit at worst causes one more or
525	 * one less debugger trap, so allowing it is fairly harmless.
526	 */
527
528#define RFLAG_SECURE(ef, oef)     ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
529	if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
530		printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags);
531		return (EINVAL);
532	}
533
534	/*
535	 * Don't allow users to load a valid privileged %cs.  Let the
536	 * hardware check for invalid selectors, excess privilege in
537	 * other selectors, invalid %eip's and invalid %esp's.
538	 */
539#define CS_SECURE(cs)           (ISPL(cs) == SEL_UPL)
540	if (!CS_SECURE(context->sc_cs)) {
541		printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs);
542		ksiginfo_init_trap(&ksi);
543		ksi.ksi_signo = SIGBUS;
544		ksi.ksi_code = BUS_OBJERR;
545		ksi.ksi_trapno = T_PROTFLT;
546		ksi.ksi_addr = (void *)regs->tf_rip;
547		trapsignal(td, &ksi);
548		return (EINVAL);
549	}
550
551	PROC_LOCK(p);
552	linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask);
553	SIG_CANTMASK(td->td_sigmask);
554	signotify(td);
555	PROC_UNLOCK(p);
556
557	regs->tf_rdi    = context->sc_rdi;
558	regs->tf_rsi    = context->sc_rsi;
559	regs->tf_rdx    = context->sc_rdx;
560	regs->tf_rbp    = context->sc_rbp;
561	regs->tf_rbx    = context->sc_rbx;
562	regs->tf_rcx    = context->sc_rcx;
563	regs->tf_rax    = context->sc_rax;
564	regs->tf_rip    = context->sc_rip;
565	regs->tf_rsp    = context->sc_rsp;
566	regs->tf_r8     = context->sc_r8;
567	regs->tf_r9     = context->sc_r9;
568	regs->tf_r10    = context->sc_r10;
569	regs->tf_r11    = context->sc_r11;
570	regs->tf_r12    = context->sc_r12;
571	regs->tf_r13    = context->sc_r13;
572	regs->tf_r14    = context->sc_r14;
573	regs->tf_r15    = context->sc_r15;
574	regs->tf_cs     = context->sc_cs;
575	regs->tf_err    = context->sc_err;
576	regs->tf_rflags = rflags;
577
578	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
579	return (EJUSTRETURN);
580}
581
582/*
583 * copied from amd64/amd64/machdep.c
584 *
585 * Send an interrupt to process.
586 */
587static void
588linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
589{
590	struct l_rt_sigframe sf, *sfp;
591	struct proc *p;
592	struct thread *td;
593	struct sigacts *psp;
594	caddr_t sp;
595	struct trapframe *regs;
596	int sig, code;
597	int oonstack;
598
599	td = curthread;
600	p = td->td_proc;
601	PROC_LOCK_ASSERT(p, MA_OWNED);
602	sig = ksi->ksi_signo;
603	psp = p->p_sigacts;
604	code = ksi->ksi_code;
605	mtx_assert(&psp->ps_mtx, MA_OWNED);
606	regs = td->td_frame;
607	oonstack = sigonstack(regs->tf_rsp);
608
609	LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u",
610	    catcher, sig, mask, code);
611
612	/* Allocate space for the signal handler context. */
613	if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
614	    SIGISMEMBER(psp->ps_sigonstack, sig)) {
615		sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size -
616		    sizeof(struct l_rt_sigframe);
617	} else
618		sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128;
619	/* Align to 16 bytes. */
620	sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul);
621	mtx_unlock(&psp->ps_mtx);
622
623	/* Translate the signal. */
624	sig = bsd_to_linux_signal(sig);
625
626	/* Save user context. */
627	bzero(&sf, sizeof(sf));
628	bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask);
629	bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask);
630
631	sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp);
632	sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size;
633	sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
634	    ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE;
635	PROC_UNLOCK(p);
636
637	sf.sf_sc.uc_mcontext.sc_rdi    = regs->tf_rdi;
638	sf.sf_sc.uc_mcontext.sc_rsi    = regs->tf_rsi;
639	sf.sf_sc.uc_mcontext.sc_rdx    = regs->tf_rdx;
640	sf.sf_sc.uc_mcontext.sc_rbp    = regs->tf_rbp;
641	sf.sf_sc.uc_mcontext.sc_rbx    = regs->tf_rbx;
642	sf.sf_sc.uc_mcontext.sc_rcx    = regs->tf_rcx;
643	sf.sf_sc.uc_mcontext.sc_rax    = regs->tf_rax;
644	sf.sf_sc.uc_mcontext.sc_rip    = regs->tf_rip;
645	sf.sf_sc.uc_mcontext.sc_rsp    = regs->tf_rsp;
646	sf.sf_sc.uc_mcontext.sc_r8     = regs->tf_r8;
647	sf.sf_sc.uc_mcontext.sc_r9     = regs->tf_r9;
648	sf.sf_sc.uc_mcontext.sc_r10    = regs->tf_r10;
649	sf.sf_sc.uc_mcontext.sc_r11    = regs->tf_r11;
650	sf.sf_sc.uc_mcontext.sc_r12    = regs->tf_r12;
651	sf.sf_sc.uc_mcontext.sc_r13    = regs->tf_r13;
652	sf.sf_sc.uc_mcontext.sc_r14    = regs->tf_r14;
653	sf.sf_sc.uc_mcontext.sc_r15    = regs->tf_r15;
654	sf.sf_sc.uc_mcontext.sc_cs     = regs->tf_cs;
655	sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags;
656	sf.sf_sc.uc_mcontext.sc_err    = regs->tf_err;
657	sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code);
658	sf.sf_sc.uc_mcontext.sc_cr2    = (register_t)ksi->ksi_addr;
659
660	/* Build the argument list for the signal handler. */
661	regs->tf_rdi = sig;			/* arg 1 in %rdi */
662	regs->tf_rax = 0;
663	regs->tf_rsi = (register_t)&sfp->sf_si;	/* arg 2 in %rsi */
664	regs->tf_rdx = (register_t)&sfp->sf_sc;	/* arg 3 in %rdx */
665
666	sf.sf_handler = catcher;
667	/* Fill in POSIX parts. */
668	ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig);
669
670	/* Copy the sigframe out to the user's stack. */
671	if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
672		PROC_LOCK(p);
673		sigexit(td, SIGILL);
674	}
675
676	regs->tf_rsp = (long)sfp;
677	regs->tf_rip = linux_rt_sigcode;
678	regs->tf_rflags &= ~(PSL_T | PSL_D);
679	regs->tf_cs = _ucodesel;
680	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
681	PROC_LOCK(p);
682	mtx_lock(&psp->ps_mtx);
683}
684
685#define	LINUX_VSYSCALL_START		(-10UL << 20)
686#define	LINUX_VSYSCALL_SZ		1024
687
688const unsigned long linux_vsyscall_vector[] = {
689	LINUX_SYS_gettimeofday,
690	LINUX_SYS_linux_time,
691	LINUX_SYS_linux_getcpu,
692};
693
694static int
695linux_vsyscall(struct thread *td)
696{
697	struct trapframe *frame;
698	uint64_t retqaddr;
699	int code, traced;
700	int error;
701
702	frame = td->td_frame;
703
704	/* Check %rip for vsyscall area. */
705	if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START))
706		return (EINVAL);
707	if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0)
708		return (EINVAL);
709	code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ;
710	if (code >= nitems(linux_vsyscall_vector))
711		return (EINVAL);
712
713	/*
714	 * vsyscall called as callq *(%rax), so we must
715	 * use return address from %rsp and also fixup %rsp.
716	 */
717	error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr));
718	if (error)
719		return (error);
720
721	frame->tf_rip = retqaddr;
722	frame->tf_rax = linux_vsyscall_vector[code];
723	frame->tf_rsp += 8;
724
725	traced = (frame->tf_flags & PSL_T);
726
727	amd64_syscall(td, traced);
728
729	return (0);
730}
731
732struct sysentvec elf_linux_sysvec = {
733	.sv_size	= LINUX_SYS_MAXSYSCALL,
734	.sv_table	= linux_sysent,
735	.sv_transtrap	= linux_translate_traps,
736	.sv_fixup	= linux_fixup_elf,
737	.sv_sendsig	= linux_rt_sendsig,
738	.sv_sigcode	= &_binary_linux_locore_o_start,
739	.sv_szsigcode	= &linux_szsigcode,
740	.sv_name	= "Linux ELF64",
741	.sv_coredump	= elf64_coredump,
742	.sv_imgact_try	= linux_exec_imgact_try,
743	.sv_minsigstksz	= LINUX_MINSIGSTKSZ,
744	.sv_minuser	= VM_MIN_ADDRESS,
745	.sv_maxuser	= VM_MAXUSER_ADDRESS_LA48,
746	.sv_usrstack	= USRSTACK_LA48,
747	.sv_psstrings	= PS_STRINGS_LA48,
748	.sv_stackprot	= VM_PROT_ALL,
749	.sv_copyout_auxargs = linux_copyout_auxargs,
750	.sv_copyout_strings = linux_copyout_strings,
751	.sv_setregs	= linux_exec_setregs,
752	.sv_fixlimit	= NULL,
753	.sv_maxssiz	= NULL,
754	.sv_flags	= SV_ABI_LINUX | SV_LP64 | SV_SHP | SV_SIG_DISCIGN |
755	    SV_SIG_WAITNDQ,
756	.sv_set_syscall_retval = linux_set_syscall_retval,
757	.sv_fetch_syscall_args = linux_fetch_syscall_args,
758	.sv_syscallnames = NULL,
759	.sv_shared_page_base = SHAREDPAGE_LA48,
760	.sv_shared_page_len = PAGE_SIZE,
761	.sv_schedtail	= linux_schedtail,
762	.sv_thread_detach = linux_thread_detach,
763	.sv_trap	= linux_vsyscall,
764	.sv_onexec	= linux_on_exec,
765	.sv_onexit	= linux_on_exit,
766	.sv_ontdexit	= linux_thread_dtor,
767	.sv_setid_allowed = &linux_setid_allowed_query,
768};
769
770static void
771linux_vdso_install(void *param)
772{
773
774	amd64_lower_shared_page(&elf_linux_sysvec);
775
776	linux_szsigcode = (&_binary_linux_locore_o_end -
777	    &_binary_linux_locore_o_start);
778
779	if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len)
780		panic("Linux invalid vdso size\n");
781
782	__elfN(linux_vdso_fixup)(&elf_linux_sysvec);
783
784	linux_shared_page_obj = __elfN(linux_shared_page_init)
785	    (&linux_shared_page_mapping);
786
787	__elfN(linux_vdso_reloc)(&elf_linux_sysvec);
788
789	bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping,
790	    linux_szsigcode);
791	elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj;
792
793	linux_kplatform = linux_shared_page_mapping +
794	    (linux_platform - (caddr_t)elf_linux_sysvec.sv_shared_page_base);
795}
796SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY,
797    linux_vdso_install, NULL);
798
799static void
800linux_vdso_deinstall(void *param)
801{
802
803	__elfN(linux_shared_page_fini)(linux_shared_page_obj,
804	    linux_shared_page_mapping);
805}
806SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST,
807    linux_vdso_deinstall, NULL);
808
809static char GNULINUX_ABI_VENDOR[] = "GNU";
810static int GNULINUX_ABI_DESC = 0;
811
812static bool
813linux_trans_osrel(const Elf_Note *note, int32_t *osrel)
814{
815	const Elf32_Word *desc;
816	uintptr_t p;
817
818	p = (uintptr_t)(note + 1);
819	p += roundup2(note->n_namesz, sizeof(Elf32_Addr));
820
821	desc = (const Elf32_Word *)p;
822	if (desc[0] != GNULINUX_ABI_DESC)
823		return (false);
824
825	/*
826	 * For Linux we encode osrel using the Linux convention of
827	 * 	(version << 16) | (major << 8) | (minor)
828	 * See macro in linux_mib.h
829	 */
830	*osrel = LINUX_KERNVER(desc[1], desc[2], desc[3]);
831
832	return (true);
833}
834
835static Elf_Brandnote linux64_brandnote = {
836	.hdr.n_namesz	= sizeof(GNULINUX_ABI_VENDOR),
837	.hdr.n_descsz	= 16,
838	.hdr.n_type	= 1,
839	.vendor		= GNULINUX_ABI_VENDOR,
840	.flags		= BN_TRANSLATE_OSREL,
841	.trans_osrel	= linux_trans_osrel
842};
843
844static Elf64_Brandinfo linux_glibc2brand = {
845	.brand		= ELFOSABI_LINUX,
846	.machine	= EM_X86_64,
847	.compat_3_brand	= "Linux",
848	.emul_path	= linux_emul_path,
849	.interp_path	= "/lib64/ld-linux-x86-64.so.2",
850	.sysvec		= &elf_linux_sysvec,
851	.interp_newpath	= NULL,
852	.brand_note	= &linux64_brandnote,
853	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
854};
855
856static Elf64_Brandinfo linux_glibc2brandshort = {
857	.brand		= ELFOSABI_LINUX,
858	.machine	= EM_X86_64,
859	.compat_3_brand	= "Linux",
860	.emul_path	= linux_emul_path,
861	.interp_path	= "/lib64/ld-linux.so.2",
862	.sysvec		= &elf_linux_sysvec,
863	.interp_newpath	= NULL,
864	.brand_note	= &linux64_brandnote,
865	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
866};
867
868static Elf64_Brandinfo linux_muslbrand = {
869	.brand		= ELFOSABI_LINUX,
870	.machine	= EM_X86_64,
871	.compat_3_brand	= "Linux",
872	.emul_path	= linux_emul_path,
873	.interp_path	= "/lib/ld-musl-x86_64.so.1",
874	.sysvec		= &elf_linux_sysvec,
875	.interp_newpath	= NULL,
876	.brand_note	= &linux64_brandnote,
877	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
878};
879
880Elf64_Brandinfo *linux_brandlist[] = {
881	&linux_glibc2brand,
882	&linux_glibc2brandshort,
883	&linux_muslbrand,
884	NULL
885};
886
887static int
888linux64_elf_modevent(module_t mod, int type, void *data)
889{
890	Elf64_Brandinfo **brandinfo;
891	int error;
892	struct linux_ioctl_handler **lihp;
893
894	error = 0;
895
896	switch(type) {
897	case MOD_LOAD:
898		for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL;
899		     ++brandinfo)
900			if (elf64_insert_brand_entry(*brandinfo) < 0)
901				error = EINVAL;
902		if (error == 0) {
903			SET_FOREACH(lihp, linux_ioctl_handler_set)
904				linux_ioctl_register_handler(*lihp);
905			stclohz = (stathz ? stathz : hz);
906			if (bootverbose)
907				printf("Linux x86-64 ELF exec handler installed\n");
908		} else
909			printf("cannot insert Linux x86-64 ELF brand handler\n");
910		break;
911	case MOD_UNLOAD:
912		for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL;
913		     ++brandinfo)
914			if (elf64_brand_inuse(*brandinfo))
915				error = EBUSY;
916		if (error == 0) {
917			for (brandinfo = &linux_brandlist[0];
918			     *brandinfo != NULL; ++brandinfo)
919				if (elf64_remove_brand_entry(*brandinfo) < 0)
920					error = EINVAL;
921		}
922		if (error == 0) {
923			SET_FOREACH(lihp, linux_ioctl_handler_set)
924				linux_ioctl_unregister_handler(*lihp);
925			if (bootverbose)
926				printf("Linux ELF exec handler removed\n");
927		} else
928			printf("Could not deinstall ELF interpreter entry\n");
929		break;
930	default:
931		return (EOPNOTSUPP);
932	}
933	return (error);
934}
935
936static moduledata_t linux64_elf_mod = {
937	"linux64elf",
938	linux64_elf_modevent,
939	0
940};
941
942DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY);
943MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1);
944FEATURE(linux64, "Linux 64bit support");
945