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linux_machdep.c revision 1.48.4.2
      1 /*	$NetBSD: linux_machdep.c,v 1.48.4.2 2020/01/21 19:19:16 martin Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2005 Emmanuel Dreyfus, all rights reserved.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  * 3. All advertising materials mentioning features or use of this software
     15  *    must display the following acknowledgement:
     16  *	This product includes software developed by Emmanuel Dreyfus
     17  * 4. The name of the author may not be used to endorse or promote
     18  *    products derived from this software without specific prior written
     19  *    permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR AND CONTRIBUTORS ``AS IS''
     22  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
     23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
     25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     31  * POSSIBILITY OF SUCH DAMAGE.
     32  */
     33 
     34 #include <sys/cdefs.h>
     35 
     36 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.48.4.2 2020/01/21 19:19:16 martin Exp $");
     37 
     38 #include <sys/param.h>
     39 #include <sys/types.h>
     40 #include <sys/systm.h>
     41 #include <sys/signal.h>
     42 #include <sys/exec.h>
     43 #include <sys/proc.h>
     44 #include <sys/ptrace.h> /* for process_read_fpregs() */
     45 #include <sys/ucontext.h>
     46 #include <sys/conf.h>
     47 
     48 #include <machine/reg.h>
     49 #include <machine/pcb.h>
     50 #include <machine/mcontext.h>
     51 #include <machine/specialreg.h>
     52 #include <machine/vmparam.h>
     53 #include <machine/cpufunc.h>
     54 #include <x86/include/sysarch.h>
     55 
     56 /*
     57  * To see whether wscons is configured (for virtual console ioctl calls).
     58  */
     59 #if defined(_KERNEL_OPT)
     60 #include "wsdisplay.h"
     61 #endif
     62 #if (NWSDISPLAY > 0)
     63 #include <dev/wscons/wsconsio.h>
     64 #include <dev/wscons/wsdisplay_usl_io.h>
     65 #endif
     66 
     67 
     68 #include <compat/linux/common/linux_signal.h>
     69 #include <compat/linux/common/linux_errno.h>
     70 #include <compat/linux/common/linux_exec.h>
     71 #include <compat/linux/common/linux_ioctl.h>
     72 #include <compat/linux/common/linux_prctl.h>
     73 #include <compat/linux/common/linux_machdep.h>
     74 #include <compat/linux/common/linux_ipc.h>
     75 #include <compat/linux/common/linux_sem.h>
     76 #include <compat/linux/linux_syscall.h>
     77 #include <compat/linux/linux_syscallargs.h>
     78 
     79 static void linux_buildcontext(struct lwp *, void *, void *);
     80 
     81 void
     82 linux_setregs(struct lwp *l, struct exec_package *epp, vaddr_t stack)
     83 {
     84 	struct pcb *pcb = lwp_getpcb(l);
     85 	struct trapframe *tf;
     86 
     87 	fpu_save_area_clear(l, __NetBSD_NPXCW__);
     88 	pcb->pcb_flags = 0;
     89 
     90 	l->l_proc->p_flag &= ~PK_32;
     91 
     92 	tf = l->l_md.md_regs;
     93 	tf->tf_rax = 0;
     94 	tf->tf_rbx = 0;
     95 	tf->tf_rcx = epp->ep_entry;
     96 	tf->tf_rdx = 0;
     97 	tf->tf_rsi = 0;
     98 	tf->tf_rdi = 0;
     99 	tf->tf_rbp = 0;
    100 	tf->tf_rsp = stack;
    101 	tf->tf_r8 = 0;
    102 	tf->tf_r9 = 0;
    103 	tf->tf_r10 = 0;
    104 	tf->tf_r11 = 0;
    105 	tf->tf_r12 = 0;
    106 	tf->tf_r13 = 0;
    107 	tf->tf_r14 = 0;
    108 	tf->tf_r15 = 0;
    109 	tf->tf_rip = epp->ep_entry;
    110 	tf->tf_rflags = PSL_USERSET;
    111 	tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL);
    112 	tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL);
    113 	tf->tf_ds = GSEL(GUDATA_SEL, SEL_UPL);
    114 	tf->tf_es = 0;
    115 	cpu_fsgs_zero(l);
    116 
    117 	return;
    118 }
    119 
    120 void
    121 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
    122 {
    123 	struct lwp *l = curlwp;
    124 	struct proc *p = l->l_proc;
    125 	struct pcb *pcb = lwp_getpcb(l);
    126 	struct sigacts *ps = p->p_sigacts;
    127 	int onstack, error;
    128 	int sig = ksi->ksi_signo;
    129 	struct linux_rt_sigframe *sfp, sigframe;
    130 	struct linux__fpstate *fpsp;
    131 	struct fpreg fpregs;
    132 	struct trapframe *tf = l->l_md.md_regs;
    133 	sig_t catcher = SIGACTION(p, sig).sa_handler;
    134 	linux_sigset_t lmask;
    135 	char *sp;
    136 
    137 	/* Do we need to jump onto the signal stack? */
    138 	onstack =
    139 	    (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
    140 	    (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
    141 
    142 	/* Allocate space for the signal handler context. */
    143 	if (onstack)
    144 		sp = ((char *)l->l_sigstk.ss_sp +
    145 		    l->l_sigstk.ss_size);
    146 	else
    147 		sp = (char *)tf->tf_rsp - 128;
    148 
    149 	/* Save FPU state */
    150 	sp = (char *) (((long)sp - sizeof (*fpsp)) & ~0xfUL);
    151 	fpsp = (struct linux__fpstate *)sp;
    152 
    153 	/*
    154 	 * Populate the rt_sigframe
    155 	 */
    156 	sp = (char *)
    157 	    ((((long)sp - sizeof(struct linux_rt_sigframe)) & ~0xfUL) - 8);
    158 	sfp = (struct linux_rt_sigframe *)sp;
    159 
    160 	memset(&sigframe, 0, sizeof(sigframe));
    161 	if (ps->sa_sigdesc[sig].sd_vers != 0)
    162 		sigframe.pretcode =
    163 		    (char *)(u_long)ps->sa_sigdesc[sig].sd_tramp;
    164 	else
    165 		sigframe.pretcode = NULL;
    166 
    167 	/*
    168 	 * The user context
    169 	 */
    170 	sigframe.uc.luc_flags = 0;
    171 	sigframe.uc.luc_link = NULL;
    172 
    173 	/* This is used regardless of SA_ONSTACK in Linux */
    174 	sigframe.uc.luc_stack.ss_sp = l->l_sigstk.ss_sp;
    175 	sigframe.uc.luc_stack.ss_size = l->l_sigstk.ss_size;
    176 	sigframe.uc.luc_stack.ss_flags = 0;
    177 	if (l->l_sigstk.ss_flags & SS_ONSTACK)
    178 		sigframe.uc.luc_stack.ss_flags |= LINUX_SS_ONSTACK;
    179 	if (l->l_sigstk.ss_flags & SS_DISABLE)
    180 		sigframe.uc.luc_stack.ss_flags |= LINUX_SS_DISABLE;
    181 
    182 	sigframe.uc.luc_mcontext.r8 = tf->tf_r8;
    183 	sigframe.uc.luc_mcontext.r9 = tf->tf_r9;
    184 	sigframe.uc.luc_mcontext.r10 = tf->tf_r10;
    185 	sigframe.uc.luc_mcontext.r11 = tf->tf_r11;
    186 	sigframe.uc.luc_mcontext.r12 = tf->tf_r12;
    187 	sigframe.uc.luc_mcontext.r13 = tf->tf_r13;
    188 	sigframe.uc.luc_mcontext.r14 = tf->tf_r14;
    189 	sigframe.uc.luc_mcontext.r15 = tf->tf_r15;
    190 	sigframe.uc.luc_mcontext.rdi = tf->tf_rdi;
    191 	sigframe.uc.luc_mcontext.rsi = tf->tf_rsi;
    192 	sigframe.uc.luc_mcontext.rbp = tf->tf_rbp;
    193 	sigframe.uc.luc_mcontext.rbx = tf->tf_rbx;
    194 	sigframe.uc.luc_mcontext.rdx = tf->tf_rdx;
    195 	sigframe.uc.luc_mcontext.rax = tf->tf_rax;
    196 	sigframe.uc.luc_mcontext.rcx = tf->tf_rcx;
    197 	sigframe.uc.luc_mcontext.rsp = tf->tf_rsp;
    198 	sigframe.uc.luc_mcontext.rip = tf->tf_rip;
    199 	sigframe.uc.luc_mcontext.eflags = tf->tf_rflags;
    200 	sigframe.uc.luc_mcontext.cs = tf->tf_cs;
    201 	sigframe.uc.luc_mcontext.gs = tf->tf_gs;
    202 	sigframe.uc.luc_mcontext.fs = tf->tf_fs;
    203 	sigframe.uc.luc_mcontext.err = tf->tf_err;
    204 	sigframe.uc.luc_mcontext.trapno = tf->tf_trapno;
    205 	native_to_linux_sigset(&lmask, mask);
    206 	sigframe.uc.luc_mcontext.oldmask = lmask.sig[0];
    207 	sigframe.uc.luc_mcontext.cr2 = (long)pcb->pcb_onfault;
    208 	sigframe.uc.luc_mcontext.fpstate = fpsp;
    209 	native_to_linux_sigset(&sigframe.uc.luc_sigmask, mask);
    210 	native_to_linux_siginfo(&sigframe.info, &ksi->ksi_info);
    211 	sendsig_reset(l, sig);
    212 	mutex_exit(p->p_lock);
    213 	error = 0;
    214 
    215 	/*
    216 	 * Save FPU state, if any
    217 	 */
    218 	if (fpsp != NULL) {
    219 		size_t fp_size = sizeof fpregs;
    220 		/* The netbsd and linux structures both match the fxsave data */
    221 		(void)process_read_fpregs(l, &fpregs, &fp_size);
    222 		error = copyout(&fpregs, fpsp, sizeof(*fpsp));
    223 	}
    224 
    225 	if (error == 0)
    226 		error = copyout(&sigframe, sp, sizeof(sigframe));
    227 
    228 	mutex_enter(p->p_lock);
    229 
    230 	if (error != 0) {
    231 		sigexit(l, SIGILL);
    232 		return;
    233 	}
    234 
    235 	if ((vaddr_t)catcher >= VM_MAXUSER_ADDRESS) {
    236 		sigexit(l, SIGILL);
    237 		return;
    238 	}
    239 
    240 	linux_buildcontext(l, catcher, sp);
    241 	tf->tf_rdi = sigframe.info.lsi_signo;
    242 	tf->tf_rax = 0;
    243 	tf->tf_rsi = (long)&sfp->info;
    244 	tf->tf_rdx = (long)&sfp->uc;
    245 
    246 	/*
    247 	 * Remember we use signal stack
    248 	 */
    249 	if (onstack)
    250 		l->l_sigstk.ss_flags |= SS_ONSTACK;
    251 	return;
    252 }
    253 
    254 int
    255 linux_sys_modify_ldt(struct lwp *l, const struct linux_sys_modify_ldt_args *v, register_t *retval)
    256 {
    257 	return 0;
    258 }
    259 
    260 int
    261 linux_sys_iopl(struct lwp *l, const struct linux_sys_iopl_args *v, register_t *retval)
    262 {
    263 	return 0;
    264 }
    265 
    266 int
    267 linux_sys_ioperm(struct lwp *l, const struct linux_sys_ioperm_args *v, register_t *retval)
    268 {
    269 	return 0;
    270 }
    271 
    272 dev_t
    273 linux_fakedev(dev_t dev, int raw)
    274 {
    275 
    276        extern const struct cdevsw ptc_cdevsw, pts_cdevsw;
    277        const struct cdevsw *cd = cdevsw_lookup(dev);
    278 
    279        if (raw) {
    280 #if (NWSDISPLAY > 0)
    281 	       extern const struct cdevsw wsdisplay_cdevsw;
    282 	       if (cd == &wsdisplay_cdevsw)
    283 		       return makedev(LINUX_CONS_MAJOR, (minor(dev) + 1));
    284 #endif
    285        }
    286 
    287        if (cd == &ptc_cdevsw)
    288 	       return makedev(LINUX_PTC_MAJOR, minor(dev));
    289        if (cd == &pts_cdevsw)
    290 	       return makedev(LINUX_PTS_MAJOR, minor(dev));
    291 
    292 	return ((minor(dev) & 0xff) | ((major(dev) & 0xfff) << 8)
    293 	    | (((unsigned long long int) (minor(dev) & ~0xff)) << 12)
    294 	    | (((unsigned long long int) (major(dev) & ~0xfff)) << 32));
    295 }
    296 
    297 int
    298 linux_machdepioctl(struct lwp *l, const struct linux_sys_ioctl_args *v, register_t *retval)
    299 {
    300 	return 0;
    301 }
    302 
    303 int
    304 linux_sys_rt_sigreturn(struct lwp *l, const void *v, register_t *retval)
    305 {
    306 	struct linux_ucontext *luctx;
    307 	struct trapframe *tf = l->l_md.md_regs;
    308 	struct linux_sigcontext *lsigctx;
    309 	struct linux_rt_sigframe frame, *fp;
    310 	ucontext_t uctx;
    311 	mcontext_t *mctx;
    312 	struct fxsave *fxarea;
    313 	int error;
    314 
    315 	fp = (struct linux_rt_sigframe *)(tf->tf_rsp - 8);
    316 	if ((error = copyin(fp, &frame, sizeof(frame))) != 0) {
    317 		mutex_enter(l->l_proc->p_lock);
    318 		sigexit(l, SIGILL);
    319 		return error;
    320 	}
    321 	luctx = &frame.uc;
    322 	lsigctx = &luctx->luc_mcontext;
    323 
    324 	memset(&uctx, 0, sizeof(uctx));
    325 	mctx = (mcontext_t *)&uctx.uc_mcontext;
    326 	fxarea = (struct fxsave *)&mctx->__fpregs;
    327 
    328 	/*
    329 	 * Set the flags. Linux always have CPU, stack and signal state,
    330 	 * FPU is optional. uc_flags is not used to tell what we have.
    331 	 */
    332 	uctx.uc_flags = (_UC_SIGMASK|_UC_CPU|_UC_STACK|_UC_CLRSTACK);
    333 	if (lsigctx->fpstate != NULL)
    334 		uctx.uc_flags |= _UC_FPU;
    335 	uctx.uc_link = NULL;
    336 
    337 	/*
    338 	 * Signal set
    339 	 */
    340 	linux_to_native_sigset(&uctx.uc_sigmask, &luctx->luc_sigmask);
    341 
    342 	/*
    343 	 * CPU state
    344 	 */
    345 	mctx->__gregs[_REG_R8] = lsigctx->r8;
    346 	mctx->__gregs[_REG_R9] = lsigctx->r9;
    347 	mctx->__gregs[_REG_R10] = lsigctx->r10;
    348 	mctx->__gregs[_REG_R11] = lsigctx->r11;
    349 	mctx->__gregs[_REG_R12] = lsigctx->r12;
    350 	mctx->__gregs[_REG_R13] = lsigctx->r13;
    351 	mctx->__gregs[_REG_R14] = lsigctx->r14;
    352 	mctx->__gregs[_REG_R15] = lsigctx->r15;
    353 	mctx->__gregs[_REG_RDI] = lsigctx->rdi;
    354 	mctx->__gregs[_REG_RSI] = lsigctx->rsi;
    355 	mctx->__gregs[_REG_RBP] = lsigctx->rbp;
    356 	mctx->__gregs[_REG_RBX] = lsigctx->rbx;
    357 	mctx->__gregs[_REG_RAX] = lsigctx->rax;
    358 	mctx->__gregs[_REG_RDX] = lsigctx->rdx;
    359 	mctx->__gregs[_REG_RCX] = lsigctx->rcx;
    360 	mctx->__gregs[_REG_RIP] = lsigctx->rip;
    361 	mctx->__gregs[_REG_RFLAGS] = lsigctx->eflags;
    362 	mctx->__gregs[_REG_CS] = lsigctx->cs;
    363 	mctx->__gregs[_REG_GS] = lsigctx->gs;
    364 	mctx->__gregs[_REG_FS] = lsigctx->fs;
    365 	mctx->__gregs[_REG_ERR] = lsigctx->err;
    366 	mctx->__gregs[_REG_TRAPNO] = lsigctx->trapno;
    367 	mctx->__gregs[_REG_ES] = tf->tf_es;
    368 	mctx->__gregs[_REG_DS] = tf->tf_ds;
    369 	mctx->__gregs[_REG_RSP] = lsigctx->rsp; /* XXX */
    370 	mctx->__gregs[_REG_SS] = tf->tf_ss;
    371 
    372 	/*
    373 	 * FPU state
    374 	 */
    375 	if (lsigctx->fpstate != NULL) {
    376 		/* Both structures match the fxstate data */
    377 		error = copyin(lsigctx->fpstate, fxarea, sizeof(*fxarea));
    378 		if (error != 0) {
    379 			mutex_enter(l->l_proc->p_lock);
    380 			sigexit(l, SIGILL);
    381 			return error;
    382 		}
    383 	}
    384 
    385 	/*
    386 	 * And the stack
    387 	 */
    388 	uctx.uc_stack.ss_flags = 0;
    389 	if (luctx->luc_stack.ss_flags & LINUX_SS_ONSTACK)
    390 		uctx.uc_stack.ss_flags |= SS_ONSTACK;
    391 
    392 	if (luctx->luc_stack.ss_flags & LINUX_SS_DISABLE)
    393 		uctx.uc_stack.ss_flags |= SS_DISABLE;
    394 
    395 	uctx.uc_stack.ss_sp = luctx->luc_stack.ss_sp;
    396 	uctx.uc_stack.ss_size = luctx->luc_stack.ss_size;
    397 
    398 	/*
    399 	 * And let setucontext deal with that.
    400 	 */
    401 	mutex_enter(l->l_proc->p_lock);
    402 	error = setucontext(l, &uctx);
    403 	mutex_exit(l->l_proc->p_lock);
    404 	if (error)
    405 		return error;
    406 
    407 	return EJUSTRETURN;
    408 }
    409 
    410 int
    411 linux_sys_arch_prctl(struct lwp *l,
    412     const struct linux_sys_arch_prctl_args *uap, register_t *retval)
    413 {
    414 	/* {
    415 		syscallarg(int) code;
    416 		syscallarg(unsigned long) addr;
    417 	} */
    418 	void *addr = (void *)SCARG(uap, addr);
    419 
    420 	switch(SCARG(uap, code)) {
    421 	case LINUX_ARCH_SET_GS:
    422 		return x86_set_sdbase(addr, 'g', l, true);
    423 
    424 	case LINUX_ARCH_GET_GS:
    425 		return x86_get_sdbase(addr, 'g');
    426 
    427 	case LINUX_ARCH_SET_FS:
    428 		return x86_set_sdbase(addr, 'f', l, true);
    429 
    430 	case LINUX_ARCH_GET_FS:
    431 		return x86_get_sdbase(addr, 'f');
    432 
    433 	default:
    434 #ifdef DEBUG_LINUX
    435 		printf("linux_sys_arch_prctl: unexpected code %d\n",
    436 		    SCARG(uap, code));
    437 #endif
    438 		return EINVAL;
    439 	}
    440 	/* NOTREACHED */
    441 }
    442 
    443 const int linux_vsyscall_to_syscall[] = {
    444 	LINUX_SYS_gettimeofday,
    445 	LINUX_SYS_time,
    446 	LINUX_SYS_nosys,	/* nosys */
    447 	LINUX_SYS_nosys,	/* nosys */
    448 };
    449 
    450 int
    451 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg)
    452 {
    453 	struct trapframe *tf = arg;
    454 	uint64_t retaddr;
    455 	size_t vsyscallnr;
    456 
    457 	/*
    458 	 * Check for a vsyscall. %rip must be the fault address,
    459 	 * and the address must be in the Linux vsyscall area.
    460 	 * Also, vsyscalls are only done at 1024-byte boundaries.
    461 	 */
    462 
    463 	if (__predict_true(trapaddr < LINUX_VSYSCALL_START))
    464 		return 0;
    465 
    466 	if (trapaddr != tf->tf_rip)
    467 		return 0;
    468 
    469 	if ((tf->tf_rip & (LINUX_VSYSCALL_SIZE - 1)) != 0)
    470 		return 0;
    471 
    472 	vsyscallnr = (tf->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SIZE;
    473 
    474 	if (vsyscallnr > LINUX_VSYSCALL_MAXNR)
    475 		return 0;
    476 
    477 	/*
    478 	 * Get the return address from the top of the stack,
    479 	 * and fix up the return address.
    480 	 * This assumes the faulting instruction was callq *reg,
    481 	 * which is the only way that vsyscalls are ever entered.
    482 	 */
    483 	if (copyin((void *)tf->tf_rsp, &retaddr, sizeof retaddr) != 0)
    484 		return 0;
    485 	if ((vaddr_t)retaddr >= VM_MAXUSER_ADDRESS)
    486 		return 0;
    487 	tf->tf_rip = retaddr;
    488 	tf->tf_rax = linux_vsyscall_to_syscall[vsyscallnr];
    489 	tf->tf_rsp += 8;	/* "pop" the return address */
    490 
    491 #if 0
    492 	printf("usertrap: rip %p rsp %p retaddr %p vsys %d sys %d\n",
    493 	    (void *)tf->tf_rip, (void *)tf->tf_rsp, (void *)retaddr,
    494 	    vsyscallnr, (int)tf->tf_rax);
    495 #endif
    496 
    497 	(*l->l_proc->p_md.md_syscall)(tf);
    498 
    499 	return 1;
    500 }
    501 
    502 static void
    503 linux_buildcontext(struct lwp *l, void *catcher, void *f)
    504 {
    505 	struct trapframe *tf = l->l_md.md_regs;
    506 
    507 	tf->tf_ds = GSEL(GUDATA_SEL, SEL_UPL);
    508 	tf->tf_rip = (u_int64_t)catcher;
    509 	tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL);
    510 	tf->tf_rflags &= ~PSL_CLEARSIG;
    511 	tf->tf_rsp = (u_int64_t)f;
    512 	tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL);
    513 }
    514