1 /*- 2 * SPDX-License-Identifier: BSD-4-Clause 3 * 4 * Copyright (C) 1994, David Greenman 5 * Copyright (c) 1990, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the University of Utah, and William Jolitz. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 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. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 */ 39 40 #include <sys/cdefs.h> 41 __FBSDID("$FreeBSD$"); 42 43 /* 44 * 386 Trap and System call handling 45 */ 46 47 #include "opt_clock.h" 48 #include "opt_compat.h" 49 #include "opt_cpu.h" 50 #include "opt_isa.h" 51 52 #include <sys/param.h> 53 #include <sys/bus.h> 54 #include <sys/systm.h> 55 #include <sys/proc.h> 56 #include <sys/pioctl.h> 57 #include <sys/kernel.h> 58 #include <sys/ktr.h> 59 #include <sys/lock.h> 60 #include <sys/mutex.h> 61 #include <sys/proc.h> 62 #include <sys/ptrace.h> 63 #include <sys/resourcevar.h> 64 #include <sys/signalvar.h> 65 #include <sys/syscall.h> 66 #include <sys/sysctl.h> 67 #include <sys/sysent.h> 68 #include <sys/uio.h> 69 #include <sys/vmmeter.h> 70 #include <security/audit/audit.h> 71 72 #include <vm/vm.h> 73 #include <vm/vm_param.h> 74 #include <vm/pmap.h> 75 #include <vm/vm_kern.h> 76 #include <vm/vm_map.h> 77 #include <vm/vm_page.h> 78 #include <vm/vm_extern.h> 79 80 #include <machine/cpu.h> 81 #include <machine/intr_machdep.h> 82 #include <machine/md_var.h> 83 84 #include <compat/freebsd32/freebsd32_signal.h> 85 #include <compat/freebsd32/freebsd32_util.h> 86 #include <compat/ia32/ia32_signal.h> 87 #include <machine/psl.h> 88 #include <machine/segments.h> 89 #include <machine/specialreg.h> 90 #include <machine/sysarch.h> 91 #include <machine/frame.h> 92 #include <machine/md_var.h> 93 #include <machine/pcb.h> 94 #include <machine/cpufunc.h> 95 96 #define IDTVEC(name) __CONCAT(X,name) 97 98 extern inthand_t IDTVEC(int0x80_syscall), IDTVEC(int0x80_syscall_pti), 99 IDTVEC(rsvd), IDTVEC(rsvd_pti); 100 101 void ia32_syscall(struct trapframe *frame); /* Called from asm code */ 102 103 void 104 ia32_set_syscall_retval(struct thread *td, int error) 105 { 106 107 cpu_set_syscall_retval(td, error); 108 } 109 110 int 111 ia32_fetch_syscall_args(struct thread *td) 112 { 113 struct proc *p; 114 struct trapframe *frame; 115 struct syscall_args *sa; 116 caddr_t params; 117 u_int32_t args[8], tmp; 118 int error, i; 119 120 p = td->td_proc; 121 frame = td->td_frame; 122 sa = &td->td_sa; 123 124 params = (caddr_t)frame->tf_rsp + sizeof(u_int32_t); 125 sa->code = frame->tf_rax; 126 127 /* 128 * Need to check if this is a 32 bit or 64 bit syscall. 129 */ 130 if (sa->code == SYS_syscall) { 131 /* 132 * Code is first argument, followed by actual args. 133 */ 134 error = fueword32(params, &tmp); 135 if (error == -1) 136 return (EFAULT); 137 sa->code = tmp; 138 params += sizeof(int); 139 } else if (sa->code == SYS___syscall) { 140 /* 141 * Like syscall, but code is a quad, so as to maintain 142 * quad alignment for the rest of the arguments. 143 * We use a 32-bit fetch in case params is not 144 * aligned. 145 */ 146 error = fueword32(params, &tmp); 147 if (error == -1) 148 return (EFAULT); 149 sa->code = tmp; 150 params += sizeof(quad_t); 151 } 152 if (p->p_sysent->sv_mask) 153 sa->code &= p->p_sysent->sv_mask; 154 if (sa->code >= p->p_sysent->sv_size) 155 sa->callp = &p->p_sysent->sv_table[0]; 156 else 157 sa->callp = &p->p_sysent->sv_table[sa->code]; 158 sa->narg = sa->callp->sy_narg; 159 160 if (params != NULL && sa->narg != 0) 161 error = copyin(params, (caddr_t)args, 162 (u_int)(sa->narg * sizeof(int))); 163 else 164 error = 0; 165 166 for (i = 0; i < sa->narg; i++) 167 sa->args[i] = args[i]; 168 169 if (error == 0) { 170 td->td_retval[0] = 0; 171 td->td_retval[1] = frame->tf_rdx; 172 } 173 174 return (error); 175 } 176 177 #include "../../kern/subr_syscall.c" 178 179 void 180 ia32_syscall(struct trapframe *frame) 181 { 182 struct thread *td; 183 register_t orig_tf_rflags; 184 int error; 185 ksiginfo_t ksi; 186 187 orig_tf_rflags = frame->tf_rflags; 188 td = curthread; 189 td->td_frame = frame; 190 191 error = syscallenter(td); 192 193 /* 194 * Traced syscall. 195 */ 196 if (orig_tf_rflags & PSL_T) { 197 frame->tf_rflags &= ~PSL_T; 198 ksiginfo_init_trap(&ksi); 199 ksi.ksi_signo = SIGTRAP; 200 ksi.ksi_code = TRAP_TRACE; 201 ksi.ksi_addr = (void *)frame->tf_rip; 202 trapsignal(td, &ksi); 203 } 204 205 syscallret(td, error); 206 } 207 208 static void 209 ia32_syscall_enable(void *dummy) 210 { 211 212 setidt(IDT_SYSCALL, pti ? &IDTVEC(int0x80_syscall_pti) : 213 &IDTVEC(int0x80_syscall), SDT_SYSIGT, SEL_UPL, 0); 214 } 215 216 static void 217 ia32_syscall_disable(void *dummy) 218 { 219 220 setidt(IDT_SYSCALL, pti ? &IDTVEC(rsvd_pti) : &IDTVEC(rsvd), 221 SDT_SYSIGT, SEL_KPL, 0); 222 } 223 224 SYSINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_enable, NULL); 225 SYSUNINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_disable, NULL); 226 227 #ifdef COMPAT_43 228 int 229 setup_lcall_gate(void) 230 { 231 struct i386_ldt_args uap; 232 struct user_segment_descriptor desc; 233 uint32_t lcall_addr; 234 int error; 235 236 bzero(&uap, sizeof(uap)); 237 uap.start = 0; 238 uap.num = 1; 239 lcall_addr = curproc->p_sysent->sv_psstrings - sz_lcall_tramp; 240 bzero(&desc, sizeof(desc)); 241 desc.sd_type = SDT_MEMERA; 242 desc.sd_dpl = SEL_UPL; 243 desc.sd_p = 1; 244 desc.sd_def32 = 1; 245 desc.sd_gran = 1; 246 desc.sd_lolimit = 0xffff; 247 desc.sd_hilimit = 0xf; 248 desc.sd_lobase = lcall_addr; 249 desc.sd_hibase = lcall_addr >> 24; 250 error = amd64_set_ldt(curthread, &uap, &desc); 251 if (error != 0) 252 return (error); 253 254 return (0); 255 } 256 #endif 257