1 /*- 2 * Copyright (C) 1994, David Greenman 3 * Copyright (c) 1990, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the University of Utah, and William Jolitz. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 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. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 */ 37 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 /* 42 * 386 Trap and System call handling 43 */ 44 45 #include "opt_clock.h" 46 #include "opt_compat.h" 47 #include "opt_cpu.h" 48 #include "opt_isa.h" 49 50 #include <sys/param.h> 51 #include <sys/bus.h> 52 #include <sys/systm.h> 53 #include <sys/proc.h> 54 #include <sys/pioctl.h> 55 #include <sys/kernel.h> 56 #include <sys/ktr.h> 57 #include <sys/lock.h> 58 #include <sys/mutex.h> 59 #include <sys/proc.h> 60 #include <sys/ptrace.h> 61 #include <sys/resourcevar.h> 62 #include <sys/signalvar.h> 63 #include <sys/syscall.h> 64 #include <sys/sysctl.h> 65 #include <sys/sysent.h> 66 #include <sys/uio.h> 67 #include <sys/vmmeter.h> 68 #include <security/audit/audit.h> 69 70 #include <vm/vm.h> 71 #include <vm/vm_param.h> 72 #include <vm/pmap.h> 73 #include <vm/vm_kern.h> 74 #include <vm/vm_map.h> 75 #include <vm/vm_page.h> 76 #include <vm/vm_extern.h> 77 78 #include <machine/cpu.h> 79 #include <machine/intr_machdep.h> 80 #include <machine/md_var.h> 81 82 #include <compat/freebsd32/freebsd32_signal.h> 83 #include <compat/freebsd32/freebsd32_util.h> 84 #include <compat/ia32/ia32_signal.h> 85 #include <machine/psl.h> 86 #include <machine/segments.h> 87 #include <machine/specialreg.h> 88 #include <machine/sysarch.h> 89 #include <machine/frame.h> 90 #include <machine/md_var.h> 91 #include <machine/pcb.h> 92 #include <machine/cpufunc.h> 93 94 #define IDTVEC(name) __CONCAT(X,name) 95 96 extern inthand_t IDTVEC(int0x80_syscall), IDTVEC(rsvd); 97 98 void ia32_syscall(struct trapframe *frame); /* Called from asm code */ 99 100 void 101 ia32_set_syscall_retval(struct thread *td, int error) 102 { 103 104 cpu_set_syscall_retval(td, error); 105 } 106 107 int 108 ia32_fetch_syscall_args(struct thread *td, struct syscall_args *sa) 109 { 110 struct proc *p; 111 struct trapframe *frame; 112 caddr_t params; 113 u_int32_t args[8], tmp; 114 int error, i; 115 116 p = td->td_proc; 117 frame = td->td_frame; 118 119 params = (caddr_t)frame->tf_rsp + sizeof(u_int32_t); 120 sa->code = frame->tf_rax; 121 122 /* 123 * Need to check if this is a 32 bit or 64 bit syscall. 124 */ 125 if (sa->code == SYS_syscall) { 126 /* 127 * Code is first argument, followed by actual args. 128 */ 129 error = fueword32(params, &tmp); 130 if (error == -1) 131 return (EFAULT); 132 sa->code = tmp; 133 params += sizeof(int); 134 } else if (sa->code == SYS___syscall) { 135 /* 136 * Like syscall, but code is a quad, so as to maintain 137 * quad alignment for the rest of the arguments. 138 * We use a 32-bit fetch in case params is not 139 * aligned. 140 */ 141 error = fueword32(params, &tmp); 142 if (error == -1) 143 return (EFAULT); 144 sa->code = tmp; 145 params += sizeof(quad_t); 146 } 147 if (p->p_sysent->sv_mask) 148 sa->code &= p->p_sysent->sv_mask; 149 if (sa->code >= p->p_sysent->sv_size) 150 sa->callp = &p->p_sysent->sv_table[0]; 151 else 152 sa->callp = &p->p_sysent->sv_table[sa->code]; 153 sa->narg = sa->callp->sy_narg; 154 155 if (params != NULL && sa->narg != 0) 156 error = copyin(params, (caddr_t)args, 157 (u_int)(sa->narg * sizeof(int))); 158 else 159 error = 0; 160 161 for (i = 0; i < sa->narg; i++) 162 sa->args[i] = args[i]; 163 164 if (error == 0) { 165 td->td_retval[0] = 0; 166 td->td_retval[1] = frame->tf_rdx; 167 } 168 169 return (error); 170 } 171 172 #include "../../kern/subr_syscall.c" 173 174 void 175 ia32_syscall(struct trapframe *frame) 176 { 177 struct thread *td; 178 struct syscall_args sa; 179 register_t orig_tf_rflags; 180 int error; 181 ksiginfo_t ksi; 182 183 orig_tf_rflags = frame->tf_rflags; 184 td = curthread; 185 td->td_frame = frame; 186 187 error = syscallenter(td, &sa); 188 189 /* 190 * Traced syscall. 191 */ 192 if (orig_tf_rflags & PSL_T) { 193 frame->tf_rflags &= ~PSL_T; 194 ksiginfo_init_trap(&ksi); 195 ksi.ksi_signo = SIGTRAP; 196 ksi.ksi_code = TRAP_TRACE; 197 ksi.ksi_addr = (void *)frame->tf_rip; 198 trapsignal(td, &ksi); 199 } 200 201 syscallret(td, error, &sa); 202 } 203 204 static void 205 ia32_syscall_enable(void *dummy) 206 { 207 208 setidt(IDT_SYSCALL, &IDTVEC(int0x80_syscall), SDT_SYSIGT, SEL_UPL, 0); 209 } 210 211 static void 212 ia32_syscall_disable(void *dummy) 213 { 214 215 setidt(IDT_SYSCALL, &IDTVEC(rsvd), SDT_SYSIGT, SEL_KPL, 0); 216 } 217 218 SYSINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_enable, NULL); 219 SYSUNINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_disable, NULL); 220 221 #ifdef COMPAT_43 222 int 223 setup_lcall_gate(void) 224 { 225 struct i386_ldt_args uap; 226 struct user_segment_descriptor descs[2]; 227 struct gate_descriptor *ssd; 228 uint32_t lcall_addr; 229 int error; 230 231 bzero(&uap, sizeof(uap)); 232 uap.start = 0; 233 uap.num = 2; 234 235 /* 236 * This is the easiest way to cut the space for system 237 * descriptor in ldt. Manually adjust the descriptor type to 238 * the call gate later. 239 */ 240 bzero(&descs[0], sizeof(descs)); 241 descs[0].sd_type = SDT_SYSNULL; 242 descs[1].sd_type = SDT_SYSNULL; 243 error = amd64_set_ldt(curthread, &uap, descs); 244 if (error != 0) 245 return (error); 246 247 lcall_addr = curproc->p_sysent->sv_psstrings - sz_lcall_tramp; 248 mtx_lock(&dt_lock); 249 ssd = (struct gate_descriptor *)(curproc->p_md.md_ldt->ldt_base); 250 bzero(ssd, sizeof(*ssd)); 251 ssd->gd_looffset = lcall_addr; 252 ssd->gd_hioffset = lcall_addr >> 16; 253 ssd->gd_selector = _ucodesel; 254 ssd->gd_type = SDT_SYSCGT; 255 ssd->gd_dpl = SEL_UPL; 256 ssd->gd_p = 1; 257 mtx_unlock(&dt_lock); 258 259 return (0); 260 } 261 #endif 262