linux_machdep.c revision 1.2
1 /* $NetBSD: linux_machdep.c,v 1.2 1995/04/22 20:26:25 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Frank van der Linden 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed for the NetBSD Project 18 * by Frank van der Linden 19 * 4. 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/param.h> 35 #include <sys/systm.h> 36 #include <sys/signalvar.h> 37 #include <sys/kernel.h> 38 #include <sys/map.h> 39 #include <sys/proc.h> 40 #include <sys/user.h> 41 #include <sys/exec.h> 42 #include <sys/buf.h> 43 #include <sys/reboot.h> 44 #include <sys/conf.h> 45 #include <sys/file.h> 46 #include <sys/callout.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #include <sys/msgbuf.h> 50 #include <sys/mount.h> 51 #include <sys/vnode.h> 52 #include <sys/device.h> 53 #include <sys/sysctl.h> 54 #include <sys/syscallargs.h> 55 #include <compat/linux/linux_types.h> 56 #include <compat/linux/linux_syscallargs.h> 57 58 #include <machine/cpu.h> 59 #include <machine/cpufunc.h> 60 #include <machine/psl.h> 61 #include <machine/reg.h> 62 #include <machine/specialreg.h> 63 #include <machine/linux_machdep.h> 64 65 /* 66 * Deal with some i386-specific things in the Linux emulation code. 67 * This means just signals for now, will include stuff like 68 * I/O map permissions and V86 mode sometime. 69 */ 70 71 /* 72 * Send an interrupt to process. 73 * 74 * Stack is set up to allow sigcode stored 75 * in u. to call routine, followed by kcall 76 * to sigreturn routine below. After sigreturn 77 * resets the signal mask, the stack, and the 78 * frame pointer, it returns to the user 79 * specified pc, psl. 80 */ 81 82 void 83 linux_sendsig(catcher, sig, mask, code) 84 sig_t catcher; 85 int sig, mask; 86 u_long code; 87 { 88 register struct proc *p = curproc; 89 register struct trapframe *tf; 90 struct linux_sigframe *fp, frame; 91 struct sigacts *psp = p->p_sigacts; 92 int oonstack; 93 extern char linux_sigcode[], linux_esigcode[]; 94 95 tf = (struct trapframe *)p->p_md.md_regs; 96 oonstack = psp->ps_sigstk.ss_flags & SA_ONSTACK; 97 98 /* 99 * Allocate space for the signal handler context. 100 */ 101 if ((psp->ps_flags & SAS_ALTSTACK) && !oonstack && 102 (psp->ps_sigonstack & sigmask(sig))) { 103 fp = (struct linux_sigframe *)(psp->ps_sigstk.ss_base + 104 psp->ps_sigstk.ss_size - sizeof(struct linux_sigframe)); 105 psp->ps_sigstk.ss_flags |= SA_ONSTACK; 106 } else { 107 fp = (struct linux_sigframe *)tf->tf_esp - 1; 108 } 109 110 frame.ls_handler = catcher; 111 frame.ls_sig = bsd_to_linux_sig(sig); 112 113 /* 114 * Build the signal context to be used by sigreturn. 115 */ 116 frame.ls_sc.lsc_mask = mask; 117 frame.ls_sc.lsc_es = tf->tf_es; 118 frame.ls_sc.lsc_fs = LSEL(LUDATA_SEL, SEL_UPL); 119 frame.ls_sc.lsc_gs = LSEL(LUDATA_SEL, SEL_UPL); 120 frame.ls_sc.lsc_ds = tf->tf_ds; 121 frame.ls_sc.lsc_edi = tf->tf_edi; 122 frame.ls_sc.lsc_esi = tf->tf_esi; 123 frame.ls_sc.lsc_ebp = tf->tf_ebp; 124 frame.ls_sc.lsc_ebx = tf->tf_ebx; 125 frame.ls_sc.lsc_edx = tf->tf_edx; 126 frame.ls_sc.lsc_ecx = tf->tf_ecx; 127 frame.ls_sc.lsc_eax = tf->tf_eax; 128 frame.ls_sc.lsc_eip = tf->tf_eip; 129 frame.ls_sc.lsc_cs = tf->tf_cs; 130 frame.ls_sc.lsc_eflags = tf->tf_eflags; 131 frame.ls_sc.lsc_esp = tf->tf_esp; 132 frame.ls_sc.lsc_ss = tf->tf_ss; 133 frame.ls_sc.lsc_err = tf->tf_err; 134 frame.ls_sc.lsc_trapno = tf->tf_trapno; 135 136 if (copyout(&frame, fp, sizeof(frame)) != 0) { 137 /* 138 * Process has trashed its stack; give it an illegal 139 * instruction to halt it in its tracks. 140 */ 141 sigexit(p, SIGILL); 142 /* NOTREACHED */ 143 } 144 145 /* 146 * Build context to run handler in. 147 */ 148 tf->tf_esp = (int)fp; 149 tf->tf_eip = (int)(((char *)PS_STRINGS) - 150 (linux_esigcode - linux_sigcode)); 151 tf->tf_eflags &= ~PSL_VM; 152 tf->tf_cs = LSEL(LUCODE_SEL, SEL_UPL); 153 tf->tf_ds = LSEL(LUDATA_SEL, SEL_UPL); 154 155 tf->tf_es = LSEL(LUDATA_SEL, SEL_UPL); 156 tf->tf_ss = LSEL(LUDATA_SEL, SEL_UPL); 157 } 158 159 /* 160 * System call to cleanup state after a signal 161 * has been taken. Reset signal mask and 162 * stack state from context left by sendsig (above). 163 * Return to previous pc and psl as specified by 164 * context left by sendsig. Check carefully to 165 * make sure that the user has not modified the 166 * psl to gain improper privileges or to cause 167 * a machine fault. 168 */ 169 int 170 linux_sigreturn(p, uap, retval) 171 struct proc *p; 172 struct linux_sigreturn_args /* { 173 syscallarg(struct linux_sigcontext *) scp; 174 } */ *uap; 175 register_t *retval; 176 { 177 struct linux_sigcontext *scp, context; 178 register struct trapframe *tf; 179 180 tf = (struct trapframe *)p->p_md.md_regs; 181 182 /* 183 * The trampoline code hands us the context. 184 * It is unsafe to keep track of it ourselves, in the event that a 185 * program jumps out of a signal handler. 186 */ 187 scp = SCARG(uap, scp); 188 if (copyin((caddr_t)scp, &context, sizeof(*scp)) != 0) 189 return (EFAULT); 190 191 /* 192 * Check for security violations. 193 */ 194 if (((context.lsc_eflags ^ tf->tf_eflags) & PSL_USERSTATIC) != 0 || 195 ISPL(context.lsc_cs) != SEL_UPL) 196 return (EINVAL); 197 198 p->p_sigacts->ps_sigstk.ss_flags &= ~SA_ONSTACK; 199 p->p_sigmask = context.lsc_mask & ~sigcantmask; 200 201 /* 202 * Restore signal context. 203 */ 204 tf->tf_es = context.lsc_es; 205 tf->tf_ds = context.lsc_ds; 206 tf->tf_edi = context.lsc_edi; 207 tf->tf_esi = context.lsc_esi; 208 tf->tf_ebp = context.lsc_ebp; 209 tf->tf_ebx = context.lsc_ebx; 210 tf->tf_edx = context.lsc_edx; 211 tf->tf_ecx = context.lsc_ecx; 212 tf->tf_eax = context.lsc_eax; 213 tf->tf_eip = context.lsc_eip; 214 tf->tf_cs = context.lsc_cs; 215 tf->tf_eflags = context.lsc_eflags; 216 tf->tf_esp = context.lsc_esp; 217 tf->tf_ss = context.lsc_ss; 218 219 return (EJUSTRETURN); 220 } 221
Indexes created Sat Sep 27 22:09:54 GMT 2025