1 /* $NetBSD: compat_16_machdep.c,v 1.26 2024/06/19 15:19:22 rin Exp $ */
2
3 /*
4 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
5 * Copyright (C) 1995, 1996 TooLs GmbH.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by TooLs GmbH.
19 * 4. The name of TooLs GmbH 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 TOOLS GMBH ``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 TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
28 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: compat_16_machdep.c,v 1.26 2024/06/19 15:19:22 rin Exp $");
36
37 #ifdef _KERNEL_OPT
38 #include "opt_altivec.h"
39 #include "opt_compat_netbsd.h"
40 #include "opt_ppcarch.h"
41 #endif
42
43 #include <sys/param.h>
44 #include <sys/mount.h>
45 #include <sys/proc.h>
46 #include <sys/syscallargs.h>
47 #include <sys/systm.h>
48 #include <sys/ucontext.h>
49
50 #include <uvm/uvm_extern.h>
51
52 #include <compat/sys/signal.h>
53 #include <compat/sys/signalvar.h>
54
55 #include <powerpc/frame.h>
56 #include <powerpc/pcb.h>
57 #include <powerpc/psl.h>
58 #include <powerpc/fpu.h>
59 #if defined(ALTIVEC) || defined(PPC_HAVE_SPE)
60 #include <powerpc/altivec.h>
61 #endif
62
63 #ifdef _LP64
64
65 /*
66 * COMPAT_16 is useful only with COMPAT_NETBSD32.
67 */
68 void
sendsig_sigcontext(const ksiginfo_t * ksi,const sigset_t * mask)69 sendsig_sigcontext(const ksiginfo_t *ksi, const sigset_t *mask)
70 {
71
72 printf("sendsig_sigcontext: illegal\n");
73 sigexit(curlwp, SIGILL);
74 }
75
76 int
compat_16_sys___sigreturn14(struct lwp * l,const struct compat_16_sys___sigreturn14_args * uap,register_t * retval)77 compat_16_sys___sigreturn14(struct lwp *l,
78 const struct compat_16_sys___sigreturn14_args *uap, register_t *retval)
79 {
80
81 return ENOSYS;
82 }
83
84 #else
85
86 /*
87 * Send a signal to process.
88 */
89 void
sendsig_sigcontext(const ksiginfo_t * ksi,const sigset_t * mask)90 sendsig_sigcontext(const ksiginfo_t *ksi, const sigset_t *mask)
91 {
92 struct lwp * const l = curlwp;
93 struct proc * const p = l->l_proc;
94 struct sigacts * const ps = p->p_sigacts;
95 struct sigcontext *fp, frame;
96 struct trapframe * const tf = l->l_md.md_utf;
97 struct utrapframe * const utf = &frame.sc_frame;
98 int onstack, error;
99 int sig = ksi->ksi_signo;
100 u_long code = KSI_TRAPCODE(ksi);
101 sig_t catcher = SIGACTION(p, sig).sa_handler;
102
103
104 /* Do we need to jump onto the signal stack? */
105 onstack =
106 (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
107 (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
108
109 /* Allocate space for the signal handler context. */
110 if (onstack)
111 fp = (struct sigcontext *)((char *)l->l_sigstk.ss_sp +
112 l->l_sigstk.ss_size);
113 else
114 fp = (struct sigcontext *)tf->tf_fixreg[1];
115 fp = (struct sigcontext *)((uintptr_t)(fp - 1) & -CALLFRAMELEN);
116
117 /* Save register context. */
118 memcpy(utf->fixreg, tf->tf_fixreg, sizeof(utf->fixreg));
119 utf->lr = tf->tf_lr;
120 utf->cr = tf->tf_cr;
121 utf->xer = tf->tf_xer;
122 utf->ctr = tf->tf_ctr;
123 utf->srr0 = tf->tf_srr0;
124 utf->srr1 = tf->tf_srr1 & PSL_USERSRR1;
125
126 #ifdef PPC_HAVE_FPU
127 const struct pcb * const pcb = lwp_getpcb(l);
128 utf->srr1 |= pcb->pcb_flags & (PCB_FE0|PCB_FE1);
129 #endif
130 #if defined(ALTIVEC) || defined(PPC_HAVE_SPE)
131 /*
132 * We can't round-trip the vector unit registers with a
133 * sigcontext, so at least get them saved into the PCB.
134 * XXX vec_save_to_mcontext() has a special hack for this.
135 */
136 vec_save_to_mcontext(l, NULL, NULL);
137 #endif
138 #ifdef PPC_OEA
139 utf->vrsave = tf->tf_vrsave;
140 utf->mq = tf->tf_mq;
141 #endif
142
143 /* Save signal stack. */
144 frame.sc_onstack = l->l_sigstk.ss_flags & SS_ONSTACK;
145
146 /* Save signal mask. */
147 frame.sc_mask = *mask;
148
149 #ifdef COMPAT_13
150 /*
151 * XXX We always have to save an old style signal mask because
152 * XXX we might be delivering a signal to a process which will
153 * XXX escape from the signal in a non-standard way and invoke
154 * XXX sigreturn() directly.
155 */
156 native_sigset_to_sigset13(mask, &frame.__sc_mask13);
157 #endif
158 sendsig_reset(l, sig);
159 mutex_exit(p->p_lock);
160 error = copyout(&frame, fp, sizeof frame);
161 mutex_enter(p->p_lock);
162
163 if (error != 0) {
164 /*
165 * Process has trashed its stack; give it an illegal
166 * instruction to halt it in its tracks.
167 */
168 sigexit(l, SIGILL);
169 /* NOTREACHED */
170 }
171
172 /*
173 * Build context to run handler in. Note the trampoline version
174 * numbers are coordinated with machine-dependent code in libc.
175 */
176 switch (ps->sa_sigdesc[sig].sd_vers) {
177 #if 1 /* COMPAT_16 */
178 case __SIGTRAMP_SIGCODE_VERSION: /* legacy on-stack sigtramp */
179 tf->tf_fixreg[1] = (register_t)fp;
180 tf->tf_lr = (register_t)catcher;
181 tf->tf_fixreg[3] = (register_t)sig;
182 tf->tf_fixreg[4] = (register_t)code;
183 tf->tf_fixreg[5] = (register_t)fp;
184 tf->tf_srr0 = (register_t)p->p_sigctx.ps_sigcode;
185 break;
186 #endif /* COMPAT_16 */
187
188 case __SIGTRAMP_SIGCONTEXT_VERSION:
189 tf->tf_fixreg[1] = (register_t)fp;
190 tf->tf_lr = (register_t)catcher;
191 tf->tf_fixreg[3] = (register_t)sig;
192 tf->tf_fixreg[4] = (register_t)code;
193 tf->tf_fixreg[5] = (register_t)fp;
194 tf->tf_srr0 = (register_t)ps->sa_sigdesc[sig].sd_tramp;
195 break;
196
197 default:
198 /* Don't know what trampoline version; kill it. */
199 sigexit(l, SIGILL);
200 }
201
202 /* Remember that we're now on the signal stack. */
203 if (onstack)
204 l->l_sigstk.ss_flags |= SS_ONSTACK;
205 }
206
207 /*
208 * System call to cleanup state after a signal handler returns.
209 */
210 int
compat_16_sys___sigreturn14(struct lwp * l,const struct compat_16_sys___sigreturn14_args * uap,register_t * retval)211 compat_16_sys___sigreturn14(struct lwp *l,
212 const struct compat_16_sys___sigreturn14_args *uap, register_t *retval)
213 {
214 /* {
215 syscallarg(struct sigcontext *) sigcntxp;
216 } */
217 struct proc * const p = l->l_proc;
218 struct sigcontext sc;
219 struct utrapframe * const utf = &sc.sc_frame;
220 int error;
221
222 /*
223 * The trampoline hands us the context.
224 * It is unsafe to keep track of it ourselves, in the event that a
225 * program jumps out of a signal handler.
226 */
227 if ((error = copyin(SCARG(uap, sigcntxp), &sc, sizeof sc)) != 0)
228 return (error);
229
230 /* Restore the register context. */
231 struct trapframe * const tf = l->l_md.md_utf;
232
233 /*
234 * Make sure SRR1 hasn't been maliciously tampered with.
235 */
236 if (!PSL_USEROK_P(sc.sc_frame.srr1))
237 return (EINVAL);
238
239 /* Restore register context. */
240 memcpy(tf->tf_fixreg, utf->fixreg, sizeof(tf->tf_fixreg));
241 tf->tf_lr = utf->lr;
242 tf->tf_cr = utf->cr;
243 tf->tf_xer = utf->xer;
244 tf->tf_ctr = utf->ctr;
245 tf->tf_srr0 = utf->srr0;
246 tf->tf_srr1 = utf->srr1;
247
248 #ifdef PPC_HAVE_FPU
249 struct pcb * const pcb = lwp_getpcb(l);
250 pcb->pcb_flags &= ~(PCB_FE0|PCB_FE1);
251 pcb->pcb_flags |= utf->srr1 & (PCB_FE0|PCB_FE1);
252 #endif
253 #if defined(ALTIVEC) || defined(PPC_HAVE_SPE)
254 /*
255 * We can't round-trip the vector unit registers with a
256 * sigcontext, so at least force them to get reloaded from
257 * the PCB (we saved them into the PCB in sendsig_sigcontext()).
258 * XXX vec_restore_from_mcontext() has a special hack for this.
259 */
260 vec_restore_from_mcontext(l, NULL);
261 #endif
262 #ifdef PPC_OEA
263 tf->tf_vrsave = utf->vrsave;
264 tf->tf_mq = utf->mq;
265 #endif
266
267 mutex_enter(p->p_lock);
268 /* Restore signal stack. */
269 if (sc.sc_onstack & SS_ONSTACK)
270 l->l_sigstk.ss_flags |= SS_ONSTACK;
271 else
272 l->l_sigstk.ss_flags &= ~SS_ONSTACK;
273 /* Restore signal mask. */
274 (void) sigprocmask1(l, SIG_SETMASK, &sc.sc_mask, 0);
275 mutex_exit(p->p_lock);
276
277 return (EJUSTRETURN);
278 }
279
280 #endif /* !_LP64 */
281