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1/*
2 * arch/s390/kernel/compat_signal.c
3 *
4 * Copyright (C) IBM Corp. 2000,2006
5 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
6 * Gerhard Tonn (ton@de.ibm.com)
7 *
8 * Copyright (C) 1991, 1992 Linus Torvalds
9 *
10 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
11 */
12
13#include <linux/compat.h>
14#include <linux/sched.h>
15#include <linux/mm.h>
16#include <linux/smp.h>
17#include <linux/kernel.h>
18#include <linux/signal.h>
19#include <linux/errno.h>
20#include <linux/wait.h>
21#include <linux/ptrace.h>
22#include <linux/unistd.h>
23#include <linux/stddef.h>
24#include <linux/tty.h>
25#include <linux/personality.h>
26#include <linux/binfmts.h>
27#include <asm/ucontext.h>
28#include <asm/uaccess.h>
29#include <asm/lowcore.h>
30#include "compat_linux.h"
31#include "compat_ptrace.h"
32#include "entry.h"
33
34#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
35
36typedef struct
37{
38 __u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
39 struct sigcontext32 sc;
40 _sigregs32 sregs;
41 int signo;
42 __u32 gprs_high[NUM_GPRS];
43 __u8 retcode[S390_SYSCALL_SIZE];
44} sigframe32;
45
46typedef struct
47{
48 __u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
49 __u8 retcode[S390_SYSCALL_SIZE];
50 compat_siginfo_t info;
51 struct ucontext32 uc;
52 __u32 gprs_high[NUM_GPRS];
53} rt_sigframe32;
54
55int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
56{
57 int err;
58
59 if (!access_ok (VERIFY_WRITE, to, sizeof(compat_siginfo_t)))
60 return -EFAULT;
61
62 /* If you change siginfo_t structure, please be sure
63 this code is fixed accordingly.
64 It should never copy any pad contained in the structure
65 to avoid security leaks, but must copy the generic
66 3 ints plus the relevant union member.
67 This routine must convert siginfo from 64bit to 32bit as well
68 at the same time. */
69 err = __put_user(from->si_signo, &to->si_signo);
70 err |= __put_user(from->si_errno, &to->si_errno);
71 err |= __put_user((short)from->si_code, &to->si_code);
72 if (from->si_code < 0)
73 err |= __copy_to_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
74 else {
75 switch (from->si_code >> 16) {
76 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
77 case __SI_MESGQ >> 16:
78 err |= __put_user(from->si_int, &to->si_int);
79 /* fallthrough */
80 case __SI_KILL >> 16:
81 err |= __put_user(from->si_pid, &to->si_pid);
82 err |= __put_user(from->si_uid, &to->si_uid);
83 break;
84 case __SI_CHLD >> 16:
85 err |= __put_user(from->si_pid, &to->si_pid);
86 err |= __put_user(from->si_uid, &to->si_uid);
87 err |= __put_user(from->si_utime, &to->si_utime);
88 err |= __put_user(from->si_stime, &to->si_stime);
89 err |= __put_user(from->si_status, &to->si_status);
90 break;
91 case __SI_FAULT >> 16:
92 err |= __put_user((unsigned long) from->si_addr,
93 &to->si_addr);
94 break;
95 case __SI_POLL >> 16:
96 err |= __put_user(from->si_band, &to->si_band);
97 err |= __put_user(from->si_fd, &to->si_fd);
98 break;
99 case __SI_TIMER >> 16:
100 err |= __put_user(from->si_tid, &to->si_tid);
101 err |= __put_user(from->si_overrun, &to->si_overrun);
102 err |= __put_user(from->si_int, &to->si_int);
103 break;
104 default:
105 break;
106 }
107 }
108 return err;
109}
110
111int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
112{
113 int err;
114 u32 tmp;
115
116 if (!access_ok (VERIFY_READ, from, sizeof(compat_siginfo_t)))
117 return -EFAULT;
118
119 err = __get_user(to->si_signo, &from->si_signo);
120 err |= __get_user(to->si_errno, &from->si_errno);
121 err |= __get_user(to->si_code, &from->si_code);
122
123 if (to->si_code < 0)
124 err |= __copy_from_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
125 else {
126 switch (to->si_code >> 16) {
127 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
128 case __SI_MESGQ >> 16:
129 err |= __get_user(to->si_int, &from->si_int);
130 /* fallthrough */
131 case __SI_KILL >> 16:
132 err |= __get_user(to->si_pid, &from->si_pid);
133 err |= __get_user(to->si_uid, &from->si_uid);
134 break;
135 case __SI_CHLD >> 16:
136 err |= __get_user(to->si_pid, &from->si_pid);
137 err |= __get_user(to->si_uid, &from->si_uid);
138 err |= __get_user(to->si_utime, &from->si_utime);
139 err |= __get_user(to->si_stime, &from->si_stime);
140 err |= __get_user(to->si_status, &from->si_status);
141 break;
142 case __SI_FAULT >> 16:
143 err |= __get_user(tmp, &from->si_addr);
144 to->si_addr = (void __user *)(u64) (tmp & PSW32_ADDR_INSN);
145 break;
146 case __SI_POLL >> 16:
147 err |= __get_user(to->si_band, &from->si_band);
148 err |= __get_user(to->si_fd, &from->si_fd);
149 break;
150 case __SI_TIMER >> 16:
151 err |= __get_user(to->si_tid, &from->si_tid);
152 err |= __get_user(to->si_overrun, &from->si_overrun);
153 err |= __get_user(to->si_int, &from->si_int);
154 break;
155 default:
156 break;
157 }
158 }
159 return err;
160}
161
162asmlinkage long
163sys32_sigaction(int sig, const struct old_sigaction32 __user *act,
164 struct old_sigaction32 __user *oact)
165{
166 struct k_sigaction new_ka, old_ka;
167 unsigned long sa_handler, sa_restorer;
168 int ret;
169
170 if (act) {
171 compat_old_sigset_t mask;
172 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
173 __get_user(sa_handler, &act->sa_handler) ||
174 __get_user(sa_restorer, &act->sa_restorer) ||
175 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
176 __get_user(mask, &act->sa_mask))
177 return -EFAULT;
178 new_ka.sa.sa_handler = (__sighandler_t) sa_handler;
179 new_ka.sa.sa_restorer = (void (*)(void)) sa_restorer;
180 siginitset(&new_ka.sa.sa_mask, mask);
181 }
182
183 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
184
185 if (!ret && oact) {
186 sa_handler = (unsigned long) old_ka.sa.sa_handler;
187 sa_restorer = (unsigned long) old_ka.sa.sa_restorer;
188 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
189 __put_user(sa_handler, &oact->sa_handler) ||
190 __put_user(sa_restorer, &oact->sa_restorer) ||
191 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
192 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
193 return -EFAULT;
194 }
195
196 return ret;
197}
198
199asmlinkage long
200sys32_rt_sigaction(int sig, const struct sigaction32 __user *act,
201 struct sigaction32 __user *oact, size_t sigsetsize)
202{
203 struct k_sigaction new_ka, old_ka;
204 unsigned long sa_handler;
205 int ret;
206 compat_sigset_t set32;
207
208 /* XXX: Don't preclude handling different sized sigset_t's. */
209 if (sigsetsize != sizeof(compat_sigset_t))
210 return -EINVAL;
211
212 if (act) {
213 ret = get_user(sa_handler, &act->sa_handler);
214 ret |= __copy_from_user(&set32, &act->sa_mask,
215 sizeof(compat_sigset_t));
216 switch (_NSIG_WORDS) {
217 case 4: new_ka.sa.sa_mask.sig[3] = set32.sig[6]
218 | (((long)set32.sig[7]) << 32);
219 case 3: new_ka.sa.sa_mask.sig[2] = set32.sig[4]
220 | (((long)set32.sig[5]) << 32);
221 case 2: new_ka.sa.sa_mask.sig[1] = set32.sig[2]
222 | (((long)set32.sig[3]) << 32);
223 case 1: new_ka.sa.sa_mask.sig[0] = set32.sig[0]
224 | (((long)set32.sig[1]) << 32);
225 }
226 ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
227
228 if (ret)
229 return -EFAULT;
230 new_ka.sa.sa_handler = (__sighandler_t) sa_handler;
231 }
232
233 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
234
235 if (!ret && oact) {
236 switch (_NSIG_WORDS) {
237 case 4:
238 set32.sig[7] = (old_ka.sa.sa_mask.sig[3] >> 32);
239 set32.sig[6] = old_ka.sa.sa_mask.sig[3];
240 case 3:
241 set32.sig[5] = (old_ka.sa.sa_mask.sig[2] >> 32);
242 set32.sig[4] = old_ka.sa.sa_mask.sig[2];
243 case 2:
244 set32.sig[3] = (old_ka.sa.sa_mask.sig[1] >> 32);
245 set32.sig[2] = old_ka.sa.sa_mask.sig[1];
246 case 1:
247 set32.sig[1] = (old_ka.sa.sa_mask.sig[0] >> 32);
248 set32.sig[0] = old_ka.sa.sa_mask.sig[0];
249 }
250 ret = put_user((unsigned long)old_ka.sa.sa_handler, &oact->sa_handler);
251 ret |= __copy_to_user(&oact->sa_mask, &set32,
252 sizeof(compat_sigset_t));
253 ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
254 }
255
256 return ret;
257}
258
259asmlinkage long
260sys32_sigaltstack(const stack_t32 __user *uss, stack_t32 __user *uoss)
261{
262 struct pt_regs *regs = task_pt_regs(current);
263 stack_t kss, koss;
264 unsigned long ss_sp;
265 int ret, err = 0;
266 mm_segment_t old_fs = get_fs();
267
268 if (uss) {
269 if (!access_ok(VERIFY_READ, uss, sizeof(*uss)))
270 return -EFAULT;
271 err |= __get_user(ss_sp, &uss->ss_sp);
272 err |= __get_user(kss.ss_size, &uss->ss_size);
273 err |= __get_user(kss.ss_flags, &uss->ss_flags);
274 if (err)
275 return -EFAULT;
276 kss.ss_sp = (void __user *) ss_sp;
277 }
278
279 set_fs (KERNEL_DS);
280 ret = do_sigaltstack((stack_t __force __user *) (uss ? &kss : NULL),
281 (stack_t __force __user *) (uoss ? &koss : NULL),
282 regs->gprs[15]);
283 set_fs (old_fs);
284
285 if (!ret && uoss) {
286 if (!access_ok(VERIFY_WRITE, uoss, sizeof(*uoss)))
287 return -EFAULT;
288 ss_sp = (unsigned long) koss.ss_sp;
289 err |= __put_user(ss_sp, &uoss->ss_sp);
290 err |= __put_user(koss.ss_size, &uoss->ss_size);
291 err |= __put_user(koss.ss_flags, &uoss->ss_flags);
292 if (err)
293 return -EFAULT;
294 }
295 return ret;
296}
297
298static int save_sigregs32(struct pt_regs *regs, _sigregs32 __user *sregs)
299{
300 _s390_regs_common32 regs32;
301 int err, i;
302
303 regs32.psw.mask = PSW32_MASK_MERGE(psw32_user_bits,
304 (__u32)(regs->psw.mask >> 32));
305 regs32.psw.addr = PSW32_ADDR_AMODE31 | (__u32) regs->psw.addr;
306 for (i = 0; i < NUM_GPRS; i++)
307 regs32.gprs[i] = (__u32) regs->gprs[i];
308 save_access_regs(current->thread.acrs);
309 memcpy(regs32.acrs, current->thread.acrs, sizeof(regs32.acrs));
310 err = __copy_to_user(&sregs->regs, ®s32, sizeof(regs32));
311 if (err)
312 return err;
313 save_fp_regs(¤t->thread.fp_regs);
314 /* s390_fp_regs and _s390_fp_regs32 are the same ! */
315 return __copy_to_user(&sregs->fpregs, ¤t->thread.fp_regs,
316 sizeof(_s390_fp_regs32));
317}
318
319static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs)
320{
321 _s390_regs_common32 regs32;
322 int err, i;
323
324 /* Alwys make any pending restarted system call return -EINTR */
325 current_thread_info()->restart_block.fn = do_no_restart_syscall;
326
327 err = __copy_from_user(®s32, &sregs->regs, sizeof(regs32));
328 if (err)
329 return err;
330 regs->psw.mask = PSW_MASK_MERGE(regs->psw.mask,
331 (__u64)regs32.psw.mask << 32);
332 regs->psw.addr = (__u64)(regs32.psw.addr & PSW32_ADDR_INSN);
333 for (i = 0; i < NUM_GPRS; i++)
334 regs->gprs[i] = (__u64) regs32.gprs[i];
335 memcpy(current->thread.acrs, regs32.acrs, sizeof(current->thread.acrs));
336 restore_access_regs(current->thread.acrs);
337
338 err = __copy_from_user(¤t->thread.fp_regs, &sregs->fpregs,
339 sizeof(_s390_fp_regs32));
340 current->thread.fp_regs.fpc &= FPC_VALID_MASK;
341 if (err)
342 return err;
343
344 restore_fp_regs(¤t->thread.fp_regs);
345 regs->svcnr = 0; /* disable syscall checks */
346 return 0;
347}
348
349static int save_sigregs_gprs_high(struct pt_regs *regs, __u32 __user *uregs)
350{
351 __u32 gprs_high[NUM_GPRS];
352 int i;
353
354 for (i = 0; i < NUM_GPRS; i++)
355 gprs_high[i] = regs->gprs[i] >> 32;
356
357 return __copy_to_user(uregs, &gprs_high, sizeof(gprs_high));
358}
359
360static int restore_sigregs_gprs_high(struct pt_regs *regs, __u32 __user *uregs)
361{
362 __u32 gprs_high[NUM_GPRS];
363 int err, i;
364
365 err = __copy_from_user(&gprs_high, uregs, sizeof(gprs_high));
366 if (err)
367 return err;
368 for (i = 0; i < NUM_GPRS; i++)
369 *(__u32 *)®s->gprs[i] = gprs_high[i];
370 return 0;
371}
372
373asmlinkage long sys32_sigreturn(void)
374{
375 struct pt_regs *regs = task_pt_regs(current);
376 sigframe32 __user *frame = (sigframe32 __user *)regs->gprs[15];
377 sigset_t set;
378
379 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
380 goto badframe;
381 if (__copy_from_user(&set.sig, &frame->sc.oldmask, _SIGMASK_COPY_SIZE32))
382 goto badframe;
383 sigdelsetmask(&set, ~_BLOCKABLE);
384 set_current_blocked(&set);
385 if (restore_sigregs32(regs, &frame->sregs))
386 goto badframe;
387 if (restore_sigregs_gprs_high(regs, frame->gprs_high))
388 goto badframe;
389 return regs->gprs[2];
390badframe:
391 force_sig(SIGSEGV, current);
392 return 0;
393}
394
395asmlinkage long sys32_rt_sigreturn(void)
396{
397 struct pt_regs *regs = task_pt_regs(current);
398 rt_sigframe32 __user *frame = (rt_sigframe32 __user *)regs->gprs[15];
399 sigset_t set;
400 stack_t st;
401 __u32 ss_sp;
402 int err;
403 mm_segment_t old_fs = get_fs();
404
405 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
406 goto badframe;
407 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
408 goto badframe;
409 sigdelsetmask(&set, ~_BLOCKABLE);
410 set_current_blocked(&set);
411 if (restore_sigregs32(regs, &frame->uc.uc_mcontext))
412 goto badframe;
413 if (restore_sigregs_gprs_high(regs, frame->gprs_high))
414 goto badframe;
415 err = __get_user(ss_sp, &frame->uc.uc_stack.ss_sp);
416 st.ss_sp = compat_ptr(ss_sp);
417 err |= __get_user(st.ss_size, &frame->uc.uc_stack.ss_size);
418 err |= __get_user(st.ss_flags, &frame->uc.uc_stack.ss_flags);
419 if (err)
420 goto badframe;
421 set_fs (KERNEL_DS);
422 do_sigaltstack((stack_t __force __user *)&st, NULL, regs->gprs[15]);
423 set_fs (old_fs);
424 return regs->gprs[2];
425badframe:
426 force_sig(SIGSEGV, current);
427 return 0;
428}
429
430/*
431 * Set up a signal frame.
432 */
433
434
435/*
436 * Determine which stack to use..
437 */
438static inline void __user *
439get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
440{
441 unsigned long sp;
442
443 /* Default to using normal stack */
444 sp = (unsigned long) A(regs->gprs[15]);
445
446 /* Overflow on alternate signal stack gives SIGSEGV. */
447 if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL))
448 return (void __user *) -1UL;
449
450 /* This is the X/Open sanctioned signal stack switching. */
451 if (ka->sa.sa_flags & SA_ONSTACK) {
452 if (! sas_ss_flags(sp))
453 sp = current->sas_ss_sp + current->sas_ss_size;
454 }
455
456 /* This is the legacy signal stack switching. */
457 else if (!user_mode(regs) &&
458 !(ka->sa.sa_flags & SA_RESTORER) &&
459 ka->sa.sa_restorer) {
460 sp = (unsigned long) ka->sa.sa_restorer;
461 }
462
463 return (void __user *)((sp - frame_size) & -8ul);
464}
465
466static inline int map_signal(int sig)
467{
468 if (current_thread_info()->exec_domain
469 && current_thread_info()->exec_domain->signal_invmap
470 && sig < 32)
471 return current_thread_info()->exec_domain->signal_invmap[sig];
472 else
473 return sig;
474}
475
476static int setup_frame32(int sig, struct k_sigaction *ka,
477 sigset_t *set, struct pt_regs * regs)
478{
479 sigframe32 __user *frame = get_sigframe(ka, regs, sizeof(sigframe32));
480 if (!access_ok(VERIFY_WRITE, frame, sizeof(sigframe32)))
481 goto give_sigsegv;
482
483 if (frame == (void __user *) -1UL)
484 goto give_sigsegv;
485
486 if (__copy_to_user(&frame->sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE32))
487 goto give_sigsegv;
488
489 if (save_sigregs32(regs, &frame->sregs))
490 goto give_sigsegv;
491 if (save_sigregs_gprs_high(regs, frame->gprs_high))
492 goto give_sigsegv;
493 if (__put_user((unsigned long) &frame->sregs, &frame->sc.sregs))
494 goto give_sigsegv;
495
496 /* Set up to return from userspace. If provided, use a stub
497 already in userspace. */
498 if (ka->sa.sa_flags & SA_RESTORER) {
499 regs->gprs[14] = (__u64) ka->sa.sa_restorer;
500 } else {
501 regs->gprs[14] = (__u64) frame->retcode;
502 if (__put_user(S390_SYSCALL_OPCODE | __NR_sigreturn,
503 (u16 __user *)(frame->retcode)))
504 goto give_sigsegv;
505 }
506
507 /* Set up backchain. */
508 if (__put_user(regs->gprs[15], (unsigned int __user *) frame))
509 goto give_sigsegv;
510
511 /* Set up registers for signal handler */
512 regs->gprs[15] = (__u64) frame;
513 regs->psw.addr = (__u64) ka->sa.sa_handler;
514
515 regs->gprs[2] = map_signal(sig);
516 regs->gprs[3] = (__u64) &frame->sc;
517
518 /* We forgot to include these in the sigcontext.
519 To avoid breaking binary compatibility, they are passed as args. */
520 regs->gprs[4] = current->thread.trap_no;
521 regs->gprs[5] = current->thread.prot_addr;
522
523 /* Place signal number on stack to allow backtrace from handler. */
524 if (__put_user(regs->gprs[2], (int __user *) &frame->signo))
525 goto give_sigsegv;
526 return 0;
527
528give_sigsegv:
529 force_sigsegv(sig, current);
530 return -EFAULT;
531}
532
533static int setup_rt_frame32(int sig, struct k_sigaction *ka, siginfo_t *info,
534 sigset_t *set, struct pt_regs * regs)
535{
536 int err = 0;
537 rt_sigframe32 __user *frame = get_sigframe(ka, regs, sizeof(rt_sigframe32));
538 if (!access_ok(VERIFY_WRITE, frame, sizeof(rt_sigframe32)))
539 goto give_sigsegv;
540
541 if (frame == (void __user *) -1UL)
542 goto give_sigsegv;
543
544 if (copy_siginfo_to_user32(&frame->info, info))
545 goto give_sigsegv;
546
547 /* Create the ucontext. */
548 err |= __put_user(UC_EXTENDED, &frame->uc.uc_flags);
549 err |= __put_user(0, &frame->uc.uc_link);
550 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
551 err |= __put_user(sas_ss_flags(regs->gprs[15]),
552 &frame->uc.uc_stack.ss_flags);
553 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
554 err |= save_sigregs32(regs, &frame->uc.uc_mcontext);
555 err |= save_sigregs_gprs_high(regs, frame->gprs_high);
556 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
557 if (err)
558 goto give_sigsegv;
559
560 /* Set up to return from userspace. If provided, use a stub
561 already in userspace. */
562 if (ka->sa.sa_flags & SA_RESTORER) {
563 regs->gprs[14] = (__u64) ka->sa.sa_restorer;
564 } else {
565 regs->gprs[14] = (__u64) frame->retcode;
566 err |= __put_user(S390_SYSCALL_OPCODE | __NR_rt_sigreturn,
567 (u16 __user *)(frame->retcode));
568 }
569
570 /* Set up backchain. */
571 if (__put_user(regs->gprs[15], (unsigned int __user *) frame))
572 goto give_sigsegv;
573
574 /* Set up registers for signal handler */
575 regs->gprs[15] = (__u64) frame;
576 regs->psw.addr = (__u64) ka->sa.sa_handler;
577
578 regs->gprs[2] = map_signal(sig);
579 regs->gprs[3] = (__u64) &frame->info;
580 regs->gprs[4] = (__u64) &frame->uc;
581 return 0;
582
583give_sigsegv:
584 force_sigsegv(sig, current);
585 return -EFAULT;
586}
587
588/*
589 * OK, we're invoking a handler
590 */
591
592int handle_signal32(unsigned long sig, struct k_sigaction *ka,
593 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
594{
595 sigset_t blocked;
596 int ret;
597
598 /* Set up the stack frame */
599 if (ka->sa.sa_flags & SA_SIGINFO)
600 ret = setup_rt_frame32(sig, ka, info, oldset, regs);
601 else
602 ret = setup_frame32(sig, ka, oldset, regs);
603 if (ret)
604 return ret;
605 sigorsets(&blocked, ¤t->blocked, &ka->sa.sa_mask);
606 if (!(ka->sa.sa_flags & SA_NODEFER))
607 sigaddset(&blocked, sig);
608 set_current_blocked(&blocked);
609 return 0;
610}
611
1/*
2 * arch/s390/kernel/compat_signal.c
3 *
4 * Copyright (C) IBM Corp. 2000,2006
5 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
6 * Gerhard Tonn (ton@de.ibm.com)
7 *
8 * Copyright (C) 1991, 1992 Linus Torvalds
9 *
10 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
11 */
12
13#include <linux/compat.h>
14#include <linux/sched.h>
15#include <linux/mm.h>
16#include <linux/smp.h>
17#include <linux/kernel.h>
18#include <linux/signal.h>
19#include <linux/errno.h>
20#include <linux/wait.h>
21#include <linux/ptrace.h>
22#include <linux/unistd.h>
23#include <linux/stddef.h>
24#include <linux/tty.h>
25#include <linux/personality.h>
26#include <linux/binfmts.h>
27#include <asm/ucontext.h>
28#include <asm/uaccess.h>
29#include <asm/lowcore.h>
30#include <asm/switch_to.h>
31#include "compat_linux.h"
32#include "compat_ptrace.h"
33#include "entry.h"
34
35typedef struct
36{
37 __u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
38 struct sigcontext32 sc;
39 _sigregs32 sregs;
40 int signo;
41 __u32 gprs_high[NUM_GPRS];
42 __u8 retcode[S390_SYSCALL_SIZE];
43} sigframe32;
44
45typedef struct
46{
47 __u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
48 __u8 retcode[S390_SYSCALL_SIZE];
49 compat_siginfo_t info;
50 struct ucontext32 uc;
51 __u32 gprs_high[NUM_GPRS];
52} rt_sigframe32;
53
54int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
55{
56 int err;
57
58 if (!access_ok (VERIFY_WRITE, to, sizeof(compat_siginfo_t)))
59 return -EFAULT;
60
61 /* If you change siginfo_t structure, please be sure
62 this code is fixed accordingly.
63 It should never copy any pad contained in the structure
64 to avoid security leaks, but must copy the generic
65 3 ints plus the relevant union member.
66 This routine must convert siginfo from 64bit to 32bit as well
67 at the same time. */
68 err = __put_user(from->si_signo, &to->si_signo);
69 err |= __put_user(from->si_errno, &to->si_errno);
70 err |= __put_user((short)from->si_code, &to->si_code);
71 if (from->si_code < 0)
72 err |= __copy_to_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
73 else {
74 switch (from->si_code >> 16) {
75 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
76 case __SI_MESGQ >> 16:
77 err |= __put_user(from->si_int, &to->si_int);
78 /* fallthrough */
79 case __SI_KILL >> 16:
80 err |= __put_user(from->si_pid, &to->si_pid);
81 err |= __put_user(from->si_uid, &to->si_uid);
82 break;
83 case __SI_CHLD >> 16:
84 err |= __put_user(from->si_pid, &to->si_pid);
85 err |= __put_user(from->si_uid, &to->si_uid);
86 err |= __put_user(from->si_utime, &to->si_utime);
87 err |= __put_user(from->si_stime, &to->si_stime);
88 err |= __put_user(from->si_status, &to->si_status);
89 break;
90 case __SI_FAULT >> 16:
91 err |= __put_user((unsigned long) from->si_addr,
92 &to->si_addr);
93 break;
94 case __SI_POLL >> 16:
95 err |= __put_user(from->si_band, &to->si_band);
96 err |= __put_user(from->si_fd, &to->si_fd);
97 break;
98 case __SI_TIMER >> 16:
99 err |= __put_user(from->si_tid, &to->si_tid);
100 err |= __put_user(from->si_overrun, &to->si_overrun);
101 err |= __put_user(from->si_int, &to->si_int);
102 break;
103 default:
104 break;
105 }
106 }
107 return err;
108}
109
110int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
111{
112 int err;
113 u32 tmp;
114
115 if (!access_ok (VERIFY_READ, from, sizeof(compat_siginfo_t)))
116 return -EFAULT;
117
118 err = __get_user(to->si_signo, &from->si_signo);
119 err |= __get_user(to->si_errno, &from->si_errno);
120 err |= __get_user(to->si_code, &from->si_code);
121
122 if (to->si_code < 0)
123 err |= __copy_from_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
124 else {
125 switch (to->si_code >> 16) {
126 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
127 case __SI_MESGQ >> 16:
128 err |= __get_user(to->si_int, &from->si_int);
129 /* fallthrough */
130 case __SI_KILL >> 16:
131 err |= __get_user(to->si_pid, &from->si_pid);
132 err |= __get_user(to->si_uid, &from->si_uid);
133 break;
134 case __SI_CHLD >> 16:
135 err |= __get_user(to->si_pid, &from->si_pid);
136 err |= __get_user(to->si_uid, &from->si_uid);
137 err |= __get_user(to->si_utime, &from->si_utime);
138 err |= __get_user(to->si_stime, &from->si_stime);
139 err |= __get_user(to->si_status, &from->si_status);
140 break;
141 case __SI_FAULT >> 16:
142 err |= __get_user(tmp, &from->si_addr);
143 to->si_addr = (void __force __user *)
144 (u64) (tmp & PSW32_ADDR_INSN);
145 break;
146 case __SI_POLL >> 16:
147 err |= __get_user(to->si_band, &from->si_band);
148 err |= __get_user(to->si_fd, &from->si_fd);
149 break;
150 case __SI_TIMER >> 16:
151 err |= __get_user(to->si_tid, &from->si_tid);
152 err |= __get_user(to->si_overrun, &from->si_overrun);
153 err |= __get_user(to->si_int, &from->si_int);
154 break;
155 default:
156 break;
157 }
158 }
159 return err;
160}
161
162asmlinkage long
163sys32_sigaction(int sig, const struct old_sigaction32 __user *act,
164 struct old_sigaction32 __user *oact)
165{
166 struct k_sigaction new_ka, old_ka;
167 unsigned long sa_handler, sa_restorer;
168 int ret;
169
170 if (act) {
171 compat_old_sigset_t mask;
172 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
173 __get_user(sa_handler, &act->sa_handler) ||
174 __get_user(sa_restorer, &act->sa_restorer) ||
175 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
176 __get_user(mask, &act->sa_mask))
177 return -EFAULT;
178 new_ka.sa.sa_handler = (__sighandler_t) sa_handler;
179 new_ka.sa.sa_restorer = (void (*)(void)) sa_restorer;
180 siginitset(&new_ka.sa.sa_mask, mask);
181 }
182
183 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
184
185 if (!ret && oact) {
186 sa_handler = (unsigned long) old_ka.sa.sa_handler;
187 sa_restorer = (unsigned long) old_ka.sa.sa_restorer;
188 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
189 __put_user(sa_handler, &oact->sa_handler) ||
190 __put_user(sa_restorer, &oact->sa_restorer) ||
191 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
192 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
193 return -EFAULT;
194 }
195
196 return ret;
197}
198
199asmlinkage long
200sys32_rt_sigaction(int sig, const struct sigaction32 __user *act,
201 struct sigaction32 __user *oact, size_t sigsetsize)
202{
203 struct k_sigaction new_ka, old_ka;
204 unsigned long sa_handler;
205 int ret;
206 compat_sigset_t set32;
207
208 /* XXX: Don't preclude handling different sized sigset_t's. */
209 if (sigsetsize != sizeof(compat_sigset_t))
210 return -EINVAL;
211
212 if (act) {
213 ret = get_user(sa_handler, &act->sa_handler);
214 ret |= __copy_from_user(&set32, &act->sa_mask,
215 sizeof(compat_sigset_t));
216 new_ka.sa.sa_mask.sig[0] =
217 set32.sig[0] | (((long)set32.sig[1]) << 32);
218 ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
219
220 if (ret)
221 return -EFAULT;
222 new_ka.sa.sa_handler = (__sighandler_t) sa_handler;
223 }
224
225 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
226
227 if (!ret && oact) {
228 set32.sig[1] = (old_ka.sa.sa_mask.sig[0] >> 32);
229 set32.sig[0] = old_ka.sa.sa_mask.sig[0];
230 ret = put_user((unsigned long)old_ka.sa.sa_handler, &oact->sa_handler);
231 ret |= __copy_to_user(&oact->sa_mask, &set32,
232 sizeof(compat_sigset_t));
233 ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
234 }
235
236 return ret;
237}
238
239asmlinkage long
240sys32_sigaltstack(const stack_t32 __user *uss, stack_t32 __user *uoss)
241{
242 struct pt_regs *regs = task_pt_regs(current);
243 stack_t kss, koss;
244 unsigned long ss_sp;
245 int ret, err = 0;
246 mm_segment_t old_fs = get_fs();
247
248 if (uss) {
249 if (!access_ok(VERIFY_READ, uss, sizeof(*uss)))
250 return -EFAULT;
251 err |= __get_user(ss_sp, &uss->ss_sp);
252 err |= __get_user(kss.ss_size, &uss->ss_size);
253 err |= __get_user(kss.ss_flags, &uss->ss_flags);
254 if (err)
255 return -EFAULT;
256 kss.ss_sp = (void __user *) ss_sp;
257 }
258
259 set_fs (KERNEL_DS);
260 ret = do_sigaltstack((stack_t __force __user *) (uss ? &kss : NULL),
261 (stack_t __force __user *) (uoss ? &koss : NULL),
262 regs->gprs[15]);
263 set_fs (old_fs);
264
265 if (!ret && uoss) {
266 if (!access_ok(VERIFY_WRITE, uoss, sizeof(*uoss)))
267 return -EFAULT;
268 ss_sp = (unsigned long) koss.ss_sp;
269 err |= __put_user(ss_sp, &uoss->ss_sp);
270 err |= __put_user(koss.ss_size, &uoss->ss_size);
271 err |= __put_user(koss.ss_flags, &uoss->ss_flags);
272 if (err)
273 return -EFAULT;
274 }
275 return ret;
276}
277
278static int save_sigregs32(struct pt_regs *regs, _sigregs32 __user *sregs)
279{
280 _s390_regs_common32 regs32;
281 int err, i;
282
283 regs32.psw.mask = psw32_user_bits |
284 ((__u32)(regs->psw.mask >> 32) & PSW32_MASK_USER);
285 regs32.psw.addr = (__u32) regs->psw.addr |
286 (__u32)(regs->psw.mask & PSW_MASK_BA);
287 for (i = 0; i < NUM_GPRS; i++)
288 regs32.gprs[i] = (__u32) regs->gprs[i];
289 save_access_regs(current->thread.acrs);
290 memcpy(regs32.acrs, current->thread.acrs, sizeof(regs32.acrs));
291 err = __copy_to_user(&sregs->regs, ®s32, sizeof(regs32));
292 if (err)
293 return err;
294 save_fp_regs(¤t->thread.fp_regs);
295 /* s390_fp_regs and _s390_fp_regs32 are the same ! */
296 return __copy_to_user(&sregs->fpregs, ¤t->thread.fp_regs,
297 sizeof(_s390_fp_regs32));
298}
299
300static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs)
301{
302 _s390_regs_common32 regs32;
303 int err, i;
304
305 /* Alwys make any pending restarted system call return -EINTR */
306 current_thread_info()->restart_block.fn = do_no_restart_syscall;
307
308 err = __copy_from_user(®s32, &sregs->regs, sizeof(regs32));
309 if (err)
310 return err;
311 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
312 (__u64)(regs32.psw.mask & PSW32_MASK_USER) << 32 |
313 (__u64)(regs32.psw.addr & PSW32_ADDR_AMODE);
314 regs->psw.addr = (__u64)(regs32.psw.addr & PSW32_ADDR_INSN);
315 for (i = 0; i < NUM_GPRS; i++)
316 regs->gprs[i] = (__u64) regs32.gprs[i];
317 memcpy(current->thread.acrs, regs32.acrs, sizeof(current->thread.acrs));
318 restore_access_regs(current->thread.acrs);
319
320 err = __copy_from_user(¤t->thread.fp_regs, &sregs->fpregs,
321 sizeof(_s390_fp_regs32));
322 current->thread.fp_regs.fpc &= FPC_VALID_MASK;
323 if (err)
324 return err;
325
326 restore_fp_regs(¤t->thread.fp_regs);
327 clear_thread_flag(TIF_SYSCALL); /* No longer in a system call */
328 return 0;
329}
330
331static int save_sigregs_gprs_high(struct pt_regs *regs, __u32 __user *uregs)
332{
333 __u32 gprs_high[NUM_GPRS];
334 int i;
335
336 for (i = 0; i < NUM_GPRS; i++)
337 gprs_high[i] = regs->gprs[i] >> 32;
338
339 return __copy_to_user(uregs, &gprs_high, sizeof(gprs_high));
340}
341
342static int restore_sigregs_gprs_high(struct pt_regs *regs, __u32 __user *uregs)
343{
344 __u32 gprs_high[NUM_GPRS];
345 int err, i;
346
347 err = __copy_from_user(&gprs_high, uregs, sizeof(gprs_high));
348 if (err)
349 return err;
350 for (i = 0; i < NUM_GPRS; i++)
351 *(__u32 *)®s->gprs[i] = gprs_high[i];
352 return 0;
353}
354
355asmlinkage long sys32_sigreturn(void)
356{
357 struct pt_regs *regs = task_pt_regs(current);
358 sigframe32 __user *frame = (sigframe32 __user *)regs->gprs[15];
359 sigset_t set;
360
361 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
362 goto badframe;
363 if (__copy_from_user(&set.sig, &frame->sc.oldmask, _SIGMASK_COPY_SIZE32))
364 goto badframe;
365 set_current_blocked(&set);
366 if (restore_sigregs32(regs, &frame->sregs))
367 goto badframe;
368 if (restore_sigregs_gprs_high(regs, frame->gprs_high))
369 goto badframe;
370 return regs->gprs[2];
371badframe:
372 force_sig(SIGSEGV, current);
373 return 0;
374}
375
376asmlinkage long sys32_rt_sigreturn(void)
377{
378 struct pt_regs *regs = task_pt_regs(current);
379 rt_sigframe32 __user *frame = (rt_sigframe32 __user *)regs->gprs[15];
380 sigset_t set;
381 stack_t st;
382 __u32 ss_sp;
383 int err;
384 mm_segment_t old_fs = get_fs();
385
386 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
387 goto badframe;
388 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
389 goto badframe;
390 set_current_blocked(&set);
391 if (restore_sigregs32(regs, &frame->uc.uc_mcontext))
392 goto badframe;
393 if (restore_sigregs_gprs_high(regs, frame->gprs_high))
394 goto badframe;
395 err = __get_user(ss_sp, &frame->uc.uc_stack.ss_sp);
396 st.ss_sp = compat_ptr(ss_sp);
397 err |= __get_user(st.ss_size, &frame->uc.uc_stack.ss_size);
398 err |= __get_user(st.ss_flags, &frame->uc.uc_stack.ss_flags);
399 if (err)
400 goto badframe;
401 set_fs (KERNEL_DS);
402 do_sigaltstack((stack_t __force __user *)&st, NULL, regs->gprs[15]);
403 set_fs (old_fs);
404 return regs->gprs[2];
405badframe:
406 force_sig(SIGSEGV, current);
407 return 0;
408}
409
410/*
411 * Set up a signal frame.
412 */
413
414
415/*
416 * Determine which stack to use..
417 */
418static inline void __user *
419get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
420{
421 unsigned long sp;
422
423 /* Default to using normal stack */
424 sp = (unsigned long) A(regs->gprs[15]);
425
426 /* Overflow on alternate signal stack gives SIGSEGV. */
427 if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL))
428 return (void __user *) -1UL;
429
430 /* This is the X/Open sanctioned signal stack switching. */
431 if (ka->sa.sa_flags & SA_ONSTACK) {
432 if (! sas_ss_flags(sp))
433 sp = current->sas_ss_sp + current->sas_ss_size;
434 }
435
436 return (void __user *)((sp - frame_size) & -8ul);
437}
438
439static inline int map_signal(int sig)
440{
441 if (current_thread_info()->exec_domain
442 && current_thread_info()->exec_domain->signal_invmap
443 && sig < 32)
444 return current_thread_info()->exec_domain->signal_invmap[sig];
445 else
446 return sig;
447}
448
449static int setup_frame32(int sig, struct k_sigaction *ka,
450 sigset_t *set, struct pt_regs * regs)
451{
452 sigframe32 __user *frame = get_sigframe(ka, regs, sizeof(sigframe32));
453 if (!access_ok(VERIFY_WRITE, frame, sizeof(sigframe32)))
454 goto give_sigsegv;
455
456 if (frame == (void __user *) -1UL)
457 goto give_sigsegv;
458
459 if (__copy_to_user(&frame->sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE32))
460 goto give_sigsegv;
461
462 if (save_sigregs32(regs, &frame->sregs))
463 goto give_sigsegv;
464 if (save_sigregs_gprs_high(regs, frame->gprs_high))
465 goto give_sigsegv;
466 if (__put_user((unsigned long) &frame->sregs, &frame->sc.sregs))
467 goto give_sigsegv;
468
469 /* Set up to return from userspace. If provided, use a stub
470 already in userspace. */
471 if (ka->sa.sa_flags & SA_RESTORER) {
472 regs->gprs[14] = (__u64) ka->sa.sa_restorer | PSW32_ADDR_AMODE;
473 } else {
474 regs->gprs[14] = (__u64) frame->retcode | PSW32_ADDR_AMODE;
475 if (__put_user(S390_SYSCALL_OPCODE | __NR_sigreturn,
476 (u16 __force __user *)(frame->retcode)))
477 goto give_sigsegv;
478 }
479
480 /* Set up backchain. */
481 if (__put_user(regs->gprs[15], (unsigned int __user *) frame))
482 goto give_sigsegv;
483
484 /* Set up registers for signal handler */
485 regs->gprs[15] = (__force __u64) frame;
486 regs->psw.mask |= PSW_MASK_BA; /* force amode 31 */
487 regs->psw.addr = (__force __u64) ka->sa.sa_handler;
488
489 regs->gprs[2] = map_signal(sig);
490 regs->gprs[3] = (__force __u64) &frame->sc;
491
492 /* We forgot to include these in the sigcontext.
493 To avoid breaking binary compatibility, they are passed as args. */
494 if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
495 sig == SIGTRAP || sig == SIGFPE) {
496 /* set extra registers only for synchronous signals */
497 regs->gprs[4] = regs->int_code & 127;
498 regs->gprs[5] = regs->int_parm_long;
499 }
500
501 /* Place signal number on stack to allow backtrace from handler. */
502 if (__put_user(regs->gprs[2], (int __force __user *) &frame->signo))
503 goto give_sigsegv;
504 return 0;
505
506give_sigsegv:
507 force_sigsegv(sig, current);
508 return -EFAULT;
509}
510
511static int setup_rt_frame32(int sig, struct k_sigaction *ka, siginfo_t *info,
512 sigset_t *set, struct pt_regs * regs)
513{
514 int err = 0;
515 rt_sigframe32 __user *frame = get_sigframe(ka, regs, sizeof(rt_sigframe32));
516 if (!access_ok(VERIFY_WRITE, frame, sizeof(rt_sigframe32)))
517 goto give_sigsegv;
518
519 if (frame == (void __user *) -1UL)
520 goto give_sigsegv;
521
522 if (copy_siginfo_to_user32(&frame->info, info))
523 goto give_sigsegv;
524
525 /* Create the ucontext. */
526 err |= __put_user(UC_EXTENDED, &frame->uc.uc_flags);
527 err |= __put_user(0, &frame->uc.uc_link);
528 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
529 err |= __put_user(sas_ss_flags(regs->gprs[15]),
530 &frame->uc.uc_stack.ss_flags);
531 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
532 err |= save_sigregs32(regs, &frame->uc.uc_mcontext);
533 err |= save_sigregs_gprs_high(regs, frame->gprs_high);
534 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
535 if (err)
536 goto give_sigsegv;
537
538 /* Set up to return from userspace. If provided, use a stub
539 already in userspace. */
540 if (ka->sa.sa_flags & SA_RESTORER) {
541 regs->gprs[14] = (__u64) ka->sa.sa_restorer | PSW32_ADDR_AMODE;
542 } else {
543 regs->gprs[14] = (__u64) frame->retcode | PSW32_ADDR_AMODE;
544 err |= __put_user(S390_SYSCALL_OPCODE | __NR_rt_sigreturn,
545 (u16 __force __user *)(frame->retcode));
546 }
547
548 /* Set up backchain. */
549 if (__put_user(regs->gprs[15], (unsigned int __force __user *) frame))
550 goto give_sigsegv;
551
552 /* Set up registers for signal handler */
553 regs->gprs[15] = (__force __u64) frame;
554 regs->psw.mask |= PSW_MASK_BA; /* force amode 31 */
555 regs->psw.addr = (__u64) ka->sa.sa_handler;
556
557 regs->gprs[2] = map_signal(sig);
558 regs->gprs[3] = (__force __u64) &frame->info;
559 regs->gprs[4] = (__force __u64) &frame->uc;
560 return 0;
561
562give_sigsegv:
563 force_sigsegv(sig, current);
564 return -EFAULT;
565}
566
567/*
568 * OK, we're invoking a handler
569 */
570
571void handle_signal32(unsigned long sig, struct k_sigaction *ka,
572 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
573{
574 int ret;
575
576 /* Set up the stack frame */
577 if (ka->sa.sa_flags & SA_SIGINFO)
578 ret = setup_rt_frame32(sig, ka, info, oldset, regs);
579 else
580 ret = setup_frame32(sig, ka, oldset, regs);
581 if (ret)
582 return;
583 signal_delivered(sig, info, ka, regs,
584 test_thread_flag(TIF_SINGLE_STEP));
585}
586