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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright IBM Corp. 2000, 2006
4 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
5 * Gerhard Tonn (ton@de.ibm.com)
6 *
7 * Copyright (C) 1991, 1992 Linus Torvalds
8 *
9 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
10 */
11
12#include <linux/compat.h>
13#include <linux/sched.h>
14#include <linux/sched/task_stack.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 <linux/uaccess.h>
29#include <asm/lowcore.h>
30#include <asm/switch_to.h>
31#include <asm/vdso.h>
32#include "compat_linux.h"
33#include "compat_ptrace.h"
34#include "entry.h"
35
36typedef struct
37{
38 __u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
39 struct sigcontext32 sc;
40 _sigregs32 sregs;
41 int signo;
42 _sigregs_ext32 sregs_ext;
43 __u16 svc_insn; /* Offset of svc_insn is NOT fixed! */
44} sigframe32;
45
46typedef struct
47{
48 __u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
49 __u16 svc_insn;
50 compat_siginfo_t info;
51 struct ucontext32 uc;
52} rt_sigframe32;
53
54/* Store registers needed to create the signal frame */
55static void store_sigregs(void)
56{
57 save_access_regs(current->thread.acrs);
58 save_fpu_regs();
59}
60
61/* Load registers after signal return */
62static void load_sigregs(void)
63{
64 restore_access_regs(current->thread.acrs);
65}
66
67static int save_sigregs32(struct pt_regs *regs, _sigregs32 __user *sregs)
68{
69 _sigregs32 user_sregs;
70 int i;
71
72 user_sregs.regs.psw.mask = (__u32)(regs->psw.mask >> 32);
73 user_sregs.regs.psw.mask &= PSW32_MASK_USER | PSW32_MASK_RI;
74 user_sregs.regs.psw.mask |= PSW32_USER_BITS;
75 user_sregs.regs.psw.addr = (__u32) regs->psw.addr |
76 (__u32)(regs->psw.mask & PSW_MASK_BA);
77 for (i = 0; i < NUM_GPRS; i++)
78 user_sregs.regs.gprs[i] = (__u32) regs->gprs[i];
79 memcpy(&user_sregs.regs.acrs, current->thread.acrs,
80 sizeof(user_sregs.regs.acrs));
81 fpregs_store((_s390_fp_regs *) &user_sregs.fpregs, ¤t->thread.fpu);
82 if (__copy_to_user(sregs, &user_sregs, sizeof(_sigregs32)))
83 return -EFAULT;
84 return 0;
85}
86
87static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs)
88{
89 _sigregs32 user_sregs;
90 int i;
91
92 /* Always make any pending restarted system call return -EINTR */
93 current->restart_block.fn = do_no_restart_syscall;
94
95 if (__copy_from_user(&user_sregs, &sregs->regs, sizeof(user_sregs)))
96 return -EFAULT;
97
98 if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW32_MASK_RI))
99 return -EINVAL;
100
101 /* Test the floating-point-control word. */
102 if (test_fp_ctl(user_sregs.fpregs.fpc))
103 return -EINVAL;
104
105 /* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */
106 regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER | PSW_MASK_RI)) |
107 (__u64)(user_sregs.regs.psw.mask & PSW32_MASK_USER) << 32 |
108 (__u64)(user_sregs.regs.psw.mask & PSW32_MASK_RI) << 32 |
109 (__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_AMODE);
110 /* Check for invalid user address space control. */
111 if ((regs->psw.mask & PSW_MASK_ASC) == PSW_ASC_HOME)
112 regs->psw.mask = PSW_ASC_PRIMARY |
113 (regs->psw.mask & ~PSW_MASK_ASC);
114 regs->psw.addr = (__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_INSN);
115 for (i = 0; i < NUM_GPRS; i++)
116 regs->gprs[i] = (__u64) user_sregs.regs.gprs[i];
117 memcpy(¤t->thread.acrs, &user_sregs.regs.acrs,
118 sizeof(current->thread.acrs));
119 fpregs_load((_s390_fp_regs *) &user_sregs.fpregs, ¤t->thread.fpu);
120
121 clear_pt_regs_flag(regs, PIF_SYSCALL); /* No longer in a system call */
122 return 0;
123}
124
125static int save_sigregs_ext32(struct pt_regs *regs,
126 _sigregs_ext32 __user *sregs_ext)
127{
128 __u32 gprs_high[NUM_GPRS];
129 __u64 vxrs[__NUM_VXRS_LOW];
130 int i;
131
132 /* Save high gprs to signal stack */
133 for (i = 0; i < NUM_GPRS; i++)
134 gprs_high[i] = regs->gprs[i] >> 32;
135 if (__copy_to_user(&sregs_ext->gprs_high, &gprs_high,
136 sizeof(sregs_ext->gprs_high)))
137 return -EFAULT;
138
139 /* Save vector registers to signal stack */
140 if (MACHINE_HAS_VX) {
141 for (i = 0; i < __NUM_VXRS_LOW; i++)
142 vxrs[i] = *((__u64 *)(current->thread.fpu.vxrs + i) + 1);
143 if (__copy_to_user(&sregs_ext->vxrs_low, vxrs,
144 sizeof(sregs_ext->vxrs_low)) ||
145 __copy_to_user(&sregs_ext->vxrs_high,
146 current->thread.fpu.vxrs + __NUM_VXRS_LOW,
147 sizeof(sregs_ext->vxrs_high)))
148 return -EFAULT;
149 }
150 return 0;
151}
152
153static int restore_sigregs_ext32(struct pt_regs *regs,
154 _sigregs_ext32 __user *sregs_ext)
155{
156 __u32 gprs_high[NUM_GPRS];
157 __u64 vxrs[__NUM_VXRS_LOW];
158 int i;
159
160 /* Restore high gprs from signal stack */
161 if (__copy_from_user(&gprs_high, &sregs_ext->gprs_high,
162 sizeof(sregs_ext->gprs_high)))
163 return -EFAULT;
164 for (i = 0; i < NUM_GPRS; i++)
165 *(__u32 *)®s->gprs[i] = gprs_high[i];
166
167 /* Restore vector registers from signal stack */
168 if (MACHINE_HAS_VX) {
169 if (__copy_from_user(vxrs, &sregs_ext->vxrs_low,
170 sizeof(sregs_ext->vxrs_low)) ||
171 __copy_from_user(current->thread.fpu.vxrs + __NUM_VXRS_LOW,
172 &sregs_ext->vxrs_high,
173 sizeof(sregs_ext->vxrs_high)))
174 return -EFAULT;
175 for (i = 0; i < __NUM_VXRS_LOW; i++)
176 *((__u64 *)(current->thread.fpu.vxrs + i) + 1) = vxrs[i];
177 }
178 return 0;
179}
180
181COMPAT_SYSCALL_DEFINE0(sigreturn)
182{
183 struct pt_regs *regs = task_pt_regs(current);
184 sigframe32 __user *frame = (sigframe32 __user *)regs->gprs[15];
185 sigset_t set;
186
187 if (get_compat_sigset(&set, (compat_sigset_t __user *)frame->sc.oldmask))
188 goto badframe;
189 set_current_blocked(&set);
190 save_fpu_regs();
191 if (restore_sigregs32(regs, &frame->sregs))
192 goto badframe;
193 if (restore_sigregs_ext32(regs, &frame->sregs_ext))
194 goto badframe;
195 load_sigregs();
196 return regs->gprs[2];
197badframe:
198 force_sig(SIGSEGV);
199 return 0;
200}
201
202COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
203{
204 struct pt_regs *regs = task_pt_regs(current);
205 rt_sigframe32 __user *frame = (rt_sigframe32 __user *)regs->gprs[15];
206 sigset_t set;
207
208 if (get_compat_sigset(&set, &frame->uc.uc_sigmask))
209 goto badframe;
210 set_current_blocked(&set);
211 if (compat_restore_altstack(&frame->uc.uc_stack))
212 goto badframe;
213 save_fpu_regs();
214 if (restore_sigregs32(regs, &frame->uc.uc_mcontext))
215 goto badframe;
216 if (restore_sigregs_ext32(regs, &frame->uc.uc_mcontext_ext))
217 goto badframe;
218 load_sigregs();
219 return regs->gprs[2];
220badframe:
221 force_sig(SIGSEGV);
222 return 0;
223}
224
225/*
226 * Set up a signal frame.
227 */
228
229
230/*
231 * Determine which stack to use..
232 */
233static inline void __user *
234get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
235{
236 unsigned long sp;
237
238 /* Default to using normal stack */
239 sp = (unsigned long) A(regs->gprs[15]);
240
241 /* Overflow on alternate signal stack gives SIGSEGV. */
242 if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL))
243 return (void __user *) -1UL;
244
245 /* This is the X/Open sanctioned signal stack switching. */
246 if (ka->sa.sa_flags & SA_ONSTACK) {
247 if (! sas_ss_flags(sp))
248 sp = current->sas_ss_sp + current->sas_ss_size;
249 }
250
251 return (void __user *)((sp - frame_size) & -8ul);
252}
253
254static int setup_frame32(struct ksignal *ksig, sigset_t *set,
255 struct pt_regs *regs)
256{
257 int sig = ksig->sig;
258 sigframe32 __user *frame;
259 unsigned long restorer;
260 size_t frame_size;
261
262 /*
263 * gprs_high are always present for 31-bit compat tasks.
264 * The space for vector registers is only allocated if
265 * the machine supports it
266 */
267 frame_size = sizeof(*frame) - sizeof(frame->sregs_ext.__reserved);
268 if (!MACHINE_HAS_VX)
269 frame_size -= sizeof(frame->sregs_ext.vxrs_low) +
270 sizeof(frame->sregs_ext.vxrs_high);
271 frame = get_sigframe(&ksig->ka, regs, frame_size);
272 if (frame == (void __user *) -1UL)
273 return -EFAULT;
274
275 /* Set up backchain. */
276 if (__put_user(regs->gprs[15], (unsigned int __user *) frame))
277 return -EFAULT;
278
279 /* Create struct sigcontext32 on the signal stack */
280 if (put_compat_sigset((compat_sigset_t __user *)frame->sc.oldmask,
281 set, sizeof(compat_sigset_t)))
282 return -EFAULT;
283 if (__put_user(ptr_to_compat(&frame->sregs), &frame->sc.sregs))
284 return -EFAULT;
285
286 /* Store registers needed to create the signal frame */
287 store_sigregs();
288
289 /* Create _sigregs32 on the signal stack */
290 if (save_sigregs32(regs, &frame->sregs))
291 return -EFAULT;
292
293 /* Place signal number on stack to allow backtrace from handler. */
294 if (__put_user(regs->gprs[2], (int __force __user *) &frame->signo))
295 return -EFAULT;
296
297 /* Create _sigregs_ext32 on the signal stack */
298 if (save_sigregs_ext32(regs, &frame->sregs_ext))
299 return -EFAULT;
300
301 /* Set up to return from userspace. If provided, use a stub
302 already in userspace. */
303 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
304 restorer = (unsigned long __force)
305 ksig->ka.sa.sa_restorer | PSW32_ADDR_AMODE;
306 } else {
307 restorer = VDSO32_SYMBOL(current, sigreturn);
308 }
309
310 /* Set up registers for signal handler */
311 regs->gprs[14] = restorer;
312 regs->gprs[15] = (__force __u64) frame;
313 /* Force 31 bit amode and default user address space control. */
314 regs->psw.mask = PSW_MASK_BA |
315 (PSW_USER_BITS & PSW_MASK_ASC) |
316 (regs->psw.mask & ~PSW_MASK_ASC);
317 regs->psw.addr = (__force __u64) ksig->ka.sa.sa_handler;
318
319 regs->gprs[2] = sig;
320 regs->gprs[3] = (__force __u64) &frame->sc;
321
322 /* We forgot to include these in the sigcontext.
323 To avoid breaking binary compatibility, they are passed as args. */
324 if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
325 sig == SIGTRAP || sig == SIGFPE) {
326 /* set extra registers only for synchronous signals */
327 regs->gprs[4] = regs->int_code & 127;
328 regs->gprs[5] = regs->int_parm_long;
329 regs->gprs[6] = current->thread.last_break;
330 }
331
332 return 0;
333}
334
335static int setup_rt_frame32(struct ksignal *ksig, sigset_t *set,
336 struct pt_regs *regs)
337{
338 rt_sigframe32 __user *frame;
339 unsigned long restorer;
340 size_t frame_size;
341 u32 uc_flags;
342
343 frame_size = sizeof(*frame) -
344 sizeof(frame->uc.uc_mcontext_ext.__reserved);
345 /*
346 * gprs_high are always present for 31-bit compat tasks.
347 * The space for vector registers is only allocated if
348 * the machine supports it
349 */
350 uc_flags = UC_GPRS_HIGH;
351 if (MACHINE_HAS_VX) {
352 uc_flags |= UC_VXRS;
353 } else
354 frame_size -= sizeof(frame->uc.uc_mcontext_ext.vxrs_low) +
355 sizeof(frame->uc.uc_mcontext_ext.vxrs_high);
356 frame = get_sigframe(&ksig->ka, regs, frame_size);
357 if (frame == (void __user *) -1UL)
358 return -EFAULT;
359
360 /* Set up backchain. */
361 if (__put_user(regs->gprs[15], (unsigned int __force __user *) frame))
362 return -EFAULT;
363
364 /* Set up to return from userspace. If provided, use a stub
365 already in userspace. */
366 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
367 restorer = (unsigned long __force)
368 ksig->ka.sa.sa_restorer | PSW32_ADDR_AMODE;
369 } else {
370 restorer = VDSO32_SYMBOL(current, rt_sigreturn);
371 }
372
373 /* Create siginfo on the signal stack */
374 if (copy_siginfo_to_user32(&frame->info, &ksig->info))
375 return -EFAULT;
376
377 /* Store registers needed to create the signal frame */
378 store_sigregs();
379
380 /* Create ucontext on the signal stack. */
381 if (__put_user(uc_flags, &frame->uc.uc_flags) ||
382 __put_user(0, &frame->uc.uc_link) ||
383 __compat_save_altstack(&frame->uc.uc_stack, regs->gprs[15]) ||
384 save_sigregs32(regs, &frame->uc.uc_mcontext) ||
385 put_compat_sigset(&frame->uc.uc_sigmask, set, sizeof(compat_sigset_t)) ||
386 save_sigregs_ext32(regs, &frame->uc.uc_mcontext_ext))
387 return -EFAULT;
388
389 /* Set up registers for signal handler */
390 regs->gprs[14] = restorer;
391 regs->gprs[15] = (__force __u64) frame;
392 /* Force 31 bit amode and default user address space control. */
393 regs->psw.mask = PSW_MASK_BA |
394 (PSW_USER_BITS & PSW_MASK_ASC) |
395 (regs->psw.mask & ~PSW_MASK_ASC);
396 regs->psw.addr = (__u64 __force) ksig->ka.sa.sa_handler;
397
398 regs->gprs[2] = ksig->sig;
399 regs->gprs[3] = (__force __u64) &frame->info;
400 regs->gprs[4] = (__force __u64) &frame->uc;
401 regs->gprs[5] = current->thread.last_break;
402 return 0;
403}
404
405/*
406 * OK, we're invoking a handler
407 */
408
409void handle_signal32(struct ksignal *ksig, sigset_t *oldset,
410 struct pt_regs *regs)
411{
412 int ret;
413
414 /* Set up the stack frame */
415 if (ksig->ka.sa.sa_flags & SA_SIGINFO)
416 ret = setup_rt_frame32(ksig, oldset, regs);
417 else
418 ret = setup_frame32(ksig, oldset, regs);
419
420 signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLE_STEP));
421}
422
1/*
2 * Copyright IBM Corp. 2000, 2006
3 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
4 * Gerhard Tonn (ton@de.ibm.com)
5 *
6 * Copyright (C) 1991, 1992 Linus Torvalds
7 *
8 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
9 */
10
11#include <linux/compat.h>
12#include <linux/sched.h>
13#include <linux/mm.h>
14#include <linux/smp.h>
15#include <linux/kernel.h>
16#include <linux/signal.h>
17#include <linux/errno.h>
18#include <linux/wait.h>
19#include <linux/ptrace.h>
20#include <linux/unistd.h>
21#include <linux/stddef.h>
22#include <linux/tty.h>
23#include <linux/personality.h>
24#include <linux/binfmts.h>
25#include <asm/ucontext.h>
26#include <asm/uaccess.h>
27#include <asm/lowcore.h>
28#include <asm/switch_to.h>
29#include "compat_linux.h"
30#include "compat_ptrace.h"
31#include "entry.h"
32
33typedef struct
34{
35 __u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
36 struct sigcontext32 sc;
37 _sigregs32 sregs;
38 int signo;
39 __u32 gprs_high[NUM_GPRS];
40 __u8 retcode[S390_SYSCALL_SIZE];
41} sigframe32;
42
43typedef struct
44{
45 __u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
46 __u8 retcode[S390_SYSCALL_SIZE];
47 compat_siginfo_t info;
48 struct ucontext32 uc;
49 __u32 gprs_high[NUM_GPRS];
50} rt_sigframe32;
51
52int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from)
53{
54 int err;
55
56 /* If you change siginfo_t structure, please be sure
57 this code is fixed accordingly.
58 It should never copy any pad contained in the structure
59 to avoid security leaks, but must copy the generic
60 3 ints plus the relevant union member.
61 This routine must convert siginfo from 64bit to 32bit as well
62 at the same time. */
63 err = __put_user(from->si_signo, &to->si_signo);
64 err |= __put_user(from->si_errno, &to->si_errno);
65 err |= __put_user((short)from->si_code, &to->si_code);
66 if (from->si_code < 0)
67 err |= __copy_to_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
68 else {
69 switch (from->si_code >> 16) {
70 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
71 case __SI_MESGQ >> 16:
72 err |= __put_user(from->si_int, &to->si_int);
73 /* fallthrough */
74 case __SI_KILL >> 16:
75 err |= __put_user(from->si_pid, &to->si_pid);
76 err |= __put_user(from->si_uid, &to->si_uid);
77 break;
78 case __SI_CHLD >> 16:
79 err |= __put_user(from->si_pid, &to->si_pid);
80 err |= __put_user(from->si_uid, &to->si_uid);
81 err |= __put_user(from->si_utime, &to->si_utime);
82 err |= __put_user(from->si_stime, &to->si_stime);
83 err |= __put_user(from->si_status, &to->si_status);
84 break;
85 case __SI_FAULT >> 16:
86 err |= __put_user((unsigned long) from->si_addr,
87 &to->si_addr);
88 break;
89 case __SI_POLL >> 16:
90 err |= __put_user(from->si_band, &to->si_band);
91 err |= __put_user(from->si_fd, &to->si_fd);
92 break;
93 case __SI_TIMER >> 16:
94 err |= __put_user(from->si_tid, &to->si_tid);
95 err |= __put_user(from->si_overrun, &to->si_overrun);
96 err |= __put_user(from->si_int, &to->si_int);
97 break;
98 default:
99 break;
100 }
101 }
102 return err ? -EFAULT : 0;
103}
104
105int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
106{
107 int err;
108 u32 tmp;
109
110 err = __get_user(to->si_signo, &from->si_signo);
111 err |= __get_user(to->si_errno, &from->si_errno);
112 err |= __get_user(to->si_code, &from->si_code);
113
114 if (to->si_code < 0)
115 err |= __copy_from_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
116 else {
117 switch (to->si_code >> 16) {
118 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
119 case __SI_MESGQ >> 16:
120 err |= __get_user(to->si_int, &from->si_int);
121 /* fallthrough */
122 case __SI_KILL >> 16:
123 err |= __get_user(to->si_pid, &from->si_pid);
124 err |= __get_user(to->si_uid, &from->si_uid);
125 break;
126 case __SI_CHLD >> 16:
127 err |= __get_user(to->si_pid, &from->si_pid);
128 err |= __get_user(to->si_uid, &from->si_uid);
129 err |= __get_user(to->si_utime, &from->si_utime);
130 err |= __get_user(to->si_stime, &from->si_stime);
131 err |= __get_user(to->si_status, &from->si_status);
132 break;
133 case __SI_FAULT >> 16:
134 err |= __get_user(tmp, &from->si_addr);
135 to->si_addr = (void __force __user *)
136 (u64) (tmp & PSW32_ADDR_INSN);
137 break;
138 case __SI_POLL >> 16:
139 err |= __get_user(to->si_band, &from->si_band);
140 err |= __get_user(to->si_fd, &from->si_fd);
141 break;
142 case __SI_TIMER >> 16:
143 err |= __get_user(to->si_tid, &from->si_tid);
144 err |= __get_user(to->si_overrun, &from->si_overrun);
145 err |= __get_user(to->si_int, &from->si_int);
146 break;
147 default:
148 break;
149 }
150 }
151 return err ? -EFAULT : 0;
152}
153
154static int save_sigregs32(struct pt_regs *regs, _sigregs32 __user *sregs)
155{
156 _sigregs32 user_sregs;
157 int i;
158
159 user_sregs.regs.psw.mask = (__u32)(regs->psw.mask >> 32);
160 user_sregs.regs.psw.mask &= PSW32_MASK_USER | PSW32_MASK_RI;
161 user_sregs.regs.psw.mask |= PSW32_USER_BITS;
162 user_sregs.regs.psw.addr = (__u32) regs->psw.addr |
163 (__u32)(regs->psw.mask & PSW_MASK_BA);
164 for (i = 0; i < NUM_GPRS; i++)
165 user_sregs.regs.gprs[i] = (__u32) regs->gprs[i];
166 save_access_regs(current->thread.acrs);
167 memcpy(&user_sregs.regs.acrs, current->thread.acrs,
168 sizeof(user_sregs.regs.acrs));
169 save_fp_ctl(¤t->thread.fp_regs.fpc);
170 save_fp_regs(current->thread.fp_regs.fprs);
171 memcpy(&user_sregs.fpregs, ¤t->thread.fp_regs,
172 sizeof(user_sregs.fpregs));
173 if (__copy_to_user(sregs, &user_sregs, sizeof(_sigregs32)))
174 return -EFAULT;
175 return 0;
176}
177
178static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs)
179{
180 _sigregs32 user_sregs;
181 int i;
182
183 /* Alwys make any pending restarted system call return -EINTR */
184 current_thread_info()->restart_block.fn = do_no_restart_syscall;
185
186 if (__copy_from_user(&user_sregs, &sregs->regs, sizeof(user_sregs)))
187 return -EFAULT;
188
189 if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW32_MASK_RI))
190 return -EINVAL;
191
192 /* Loading the floating-point-control word can fail. Do that first. */
193 if (restore_fp_ctl(&user_sregs.fpregs.fpc))
194 return -EINVAL;
195
196 /* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */
197 regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER | PSW_MASK_RI)) |
198 (__u64)(user_sregs.regs.psw.mask & PSW32_MASK_USER) << 32 |
199 (__u64)(user_sregs.regs.psw.mask & PSW32_MASK_RI) << 32 |
200 (__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_AMODE);
201 /* Check for invalid user address space control. */
202 if ((regs->psw.mask & PSW_MASK_ASC) == PSW_ASC_HOME)
203 regs->psw.mask = PSW_ASC_PRIMARY |
204 (regs->psw.mask & ~PSW_MASK_ASC);
205 regs->psw.addr = (__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_INSN);
206 for (i = 0; i < NUM_GPRS; i++)
207 regs->gprs[i] = (__u64) user_sregs.regs.gprs[i];
208 memcpy(¤t->thread.acrs, &user_sregs.regs.acrs,
209 sizeof(current->thread.acrs));
210 restore_access_regs(current->thread.acrs);
211
212 memcpy(¤t->thread.fp_regs, &user_sregs.fpregs,
213 sizeof(current->thread.fp_regs));
214
215 restore_fp_regs(current->thread.fp_regs.fprs);
216 clear_thread_flag(TIF_SYSCALL); /* No longer in a system call */
217 return 0;
218}
219
220static int save_sigregs_gprs_high(struct pt_regs *regs, __u32 __user *uregs)
221{
222 __u32 gprs_high[NUM_GPRS];
223 int i;
224
225 for (i = 0; i < NUM_GPRS; i++)
226 gprs_high[i] = regs->gprs[i] >> 32;
227 if (__copy_to_user(uregs, &gprs_high, sizeof(gprs_high)))
228 return -EFAULT;
229 return 0;
230}
231
232static int restore_sigregs_gprs_high(struct pt_regs *regs, __u32 __user *uregs)
233{
234 __u32 gprs_high[NUM_GPRS];
235 int i;
236
237 if (__copy_from_user(&gprs_high, uregs, sizeof(gprs_high)))
238 return -EFAULT;
239 for (i = 0; i < NUM_GPRS; i++)
240 *(__u32 *)®s->gprs[i] = gprs_high[i];
241 return 0;
242}
243
244COMPAT_SYSCALL_DEFINE0(sigreturn)
245{
246 struct pt_regs *regs = task_pt_regs(current);
247 sigframe32 __user *frame = (sigframe32 __user *)regs->gprs[15];
248 sigset_t set;
249
250 if (__copy_from_user(&set.sig, &frame->sc.oldmask, _SIGMASK_COPY_SIZE32))
251 goto badframe;
252 set_current_blocked(&set);
253 if (restore_sigregs32(regs, &frame->sregs))
254 goto badframe;
255 if (restore_sigregs_gprs_high(regs, frame->gprs_high))
256 goto badframe;
257 return regs->gprs[2];
258badframe:
259 force_sig(SIGSEGV, current);
260 return 0;
261}
262
263COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
264{
265 struct pt_regs *regs = task_pt_regs(current);
266 rt_sigframe32 __user *frame = (rt_sigframe32 __user *)regs->gprs[15];
267 sigset_t set;
268
269 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
270 goto badframe;
271 set_current_blocked(&set);
272 if (restore_sigregs32(regs, &frame->uc.uc_mcontext))
273 goto badframe;
274 if (restore_sigregs_gprs_high(regs, frame->gprs_high))
275 goto badframe;
276 if (compat_restore_altstack(&frame->uc.uc_stack))
277 goto badframe;
278 return regs->gprs[2];
279badframe:
280 force_sig(SIGSEGV, current);
281 return 0;
282}
283
284/*
285 * Set up a signal frame.
286 */
287
288
289/*
290 * Determine which stack to use..
291 */
292static inline void __user *
293get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
294{
295 unsigned long sp;
296
297 /* Default to using normal stack */
298 sp = (unsigned long) A(regs->gprs[15]);
299
300 /* Overflow on alternate signal stack gives SIGSEGV. */
301 if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL))
302 return (void __user *) -1UL;
303
304 /* This is the X/Open sanctioned signal stack switching. */
305 if (ka->sa.sa_flags & SA_ONSTACK) {
306 if (! sas_ss_flags(sp))
307 sp = current->sas_ss_sp + current->sas_ss_size;
308 }
309
310 return (void __user *)((sp - frame_size) & -8ul);
311}
312
313static inline int map_signal(int sig)
314{
315 if (current_thread_info()->exec_domain
316 && current_thread_info()->exec_domain->signal_invmap
317 && sig < 32)
318 return current_thread_info()->exec_domain->signal_invmap[sig];
319 else
320 return sig;
321}
322
323static int setup_frame32(int sig, struct k_sigaction *ka,
324 sigset_t *set, struct pt_regs * regs)
325{
326 sigframe32 __user *frame = get_sigframe(ka, regs, sizeof(sigframe32));
327
328 if (frame == (void __user *) -1UL)
329 goto give_sigsegv;
330
331 if (__copy_to_user(&frame->sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE32))
332 goto give_sigsegv;
333
334 if (save_sigregs32(regs, &frame->sregs))
335 goto give_sigsegv;
336 if (save_sigregs_gprs_high(regs, frame->gprs_high))
337 goto give_sigsegv;
338 if (__put_user((unsigned long) &frame->sregs, &frame->sc.sregs))
339 goto give_sigsegv;
340
341 /* Set up to return from userspace. If provided, use a stub
342 already in userspace. */
343 if (ka->sa.sa_flags & SA_RESTORER) {
344 regs->gprs[14] = (__u64 __force) ka->sa.sa_restorer | PSW32_ADDR_AMODE;
345 } else {
346 regs->gprs[14] = (__u64 __force) frame->retcode | PSW32_ADDR_AMODE;
347 if (__put_user(S390_SYSCALL_OPCODE | __NR_sigreturn,
348 (u16 __force __user *)(frame->retcode)))
349 goto give_sigsegv;
350 }
351
352 /* Set up backchain. */
353 if (__put_user(regs->gprs[15], (unsigned int __user *) frame))
354 goto give_sigsegv;
355
356 /* Set up registers for signal handler */
357 regs->gprs[15] = (__force __u64) frame;
358 /* Force 31 bit amode and default user address space control. */
359 regs->psw.mask = PSW_MASK_BA |
360 (PSW_USER_BITS & PSW_MASK_ASC) |
361 (regs->psw.mask & ~PSW_MASK_ASC);
362 regs->psw.addr = (__force __u64) ka->sa.sa_handler;
363
364 regs->gprs[2] = map_signal(sig);
365 regs->gprs[3] = (__force __u64) &frame->sc;
366
367 /* We forgot to include these in the sigcontext.
368 To avoid breaking binary compatibility, they are passed as args. */
369 if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
370 sig == SIGTRAP || sig == SIGFPE) {
371 /* set extra registers only for synchronous signals */
372 regs->gprs[4] = regs->int_code & 127;
373 regs->gprs[5] = regs->int_parm_long;
374 regs->gprs[6] = task_thread_info(current)->last_break;
375 }
376
377 /* Place signal number on stack to allow backtrace from handler. */
378 if (__put_user(regs->gprs[2], (int __force __user *) &frame->signo))
379 goto give_sigsegv;
380 return 0;
381
382give_sigsegv:
383 force_sigsegv(sig, current);
384 return -EFAULT;
385}
386
387static int setup_rt_frame32(int sig, struct k_sigaction *ka, siginfo_t *info,
388 sigset_t *set, struct pt_regs * regs)
389{
390 int err = 0;
391 rt_sigframe32 __user *frame = get_sigframe(ka, regs, sizeof(rt_sigframe32));
392
393 if (frame == (void __user *) -1UL)
394 goto give_sigsegv;
395
396 if (copy_siginfo_to_user32(&frame->info, info))
397 goto give_sigsegv;
398
399 /* Create the ucontext. */
400 err |= __put_user(UC_EXTENDED, &frame->uc.uc_flags);
401 err |= __put_user(0, &frame->uc.uc_link);
402 err |= __compat_save_altstack(&frame->uc.uc_stack, regs->gprs[15]);
403 err |= save_sigregs32(regs, &frame->uc.uc_mcontext);
404 err |= save_sigregs_gprs_high(regs, frame->gprs_high);
405 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
406 if (err)
407 goto give_sigsegv;
408
409 /* Set up to return from userspace. If provided, use a stub
410 already in userspace. */
411 if (ka->sa.sa_flags & SA_RESTORER) {
412 regs->gprs[14] = (__u64 __force) ka->sa.sa_restorer | PSW32_ADDR_AMODE;
413 } else {
414 regs->gprs[14] = (__u64 __force) frame->retcode | PSW32_ADDR_AMODE;
415 if (__put_user(S390_SYSCALL_OPCODE | __NR_rt_sigreturn,
416 (u16 __force __user *)(frame->retcode)))
417 goto give_sigsegv;
418 }
419
420 /* Set up backchain. */
421 if (__put_user(regs->gprs[15], (unsigned int __force __user *) frame))
422 goto give_sigsegv;
423
424 /* Set up registers for signal handler */
425 regs->gprs[15] = (__force __u64) frame;
426 /* Force 31 bit amode and default user address space control. */
427 regs->psw.mask = PSW_MASK_BA |
428 (PSW_USER_BITS & PSW_MASK_ASC) |
429 (regs->psw.mask & ~PSW_MASK_ASC);
430 regs->psw.addr = (__u64 __force) ka->sa.sa_handler;
431
432 regs->gprs[2] = map_signal(sig);
433 regs->gprs[3] = (__force __u64) &frame->info;
434 regs->gprs[4] = (__force __u64) &frame->uc;
435 regs->gprs[5] = task_thread_info(current)->last_break;
436 return 0;
437
438give_sigsegv:
439 force_sigsegv(sig, current);
440 return -EFAULT;
441}
442
443/*
444 * OK, we're invoking a handler
445 */
446
447void handle_signal32(unsigned long sig, struct k_sigaction *ka,
448 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
449{
450 int ret;
451
452 /* Set up the stack frame */
453 if (ka->sa.sa_flags & SA_SIGINFO)
454 ret = setup_rt_frame32(sig, ka, info, oldset, regs);
455 else
456 ret = setup_frame32(sig, ka, oldset, regs);
457 if (ret)
458 return;
459 signal_delivered(sig, info, ka, regs,
460 test_thread_flag(TIF_SINGLE_STEP));
461}
462