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1/*
2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
12 * more details.
13 */
14
15#include <linux/sched.h>
16#include <linux/mm.h>
17#include <linux/smp.h>
18#include <linux/kernel.h>
19#include <linux/signal.h>
20#include <linux/errno.h>
21#include <linux/wait.h>
22#include <linux/unistd.h>
23#include <linux/stddef.h>
24#include <linux/personality.h>
25#include <linux/suspend.h>
26#include <linux/ptrace.h>
27#include <linux/elf.h>
28#include <linux/compat.h>
29#include <linux/syscalls.h>
30#include <linux/uaccess.h>
31#include <asm/processor.h>
32#include <asm/ucontext.h>
33#include <asm/sigframe.h>
34#include <asm/syscalls.h>
35#include <arch/interrupts.h>
36
37struct compat_sigaction {
38 compat_uptr_t sa_handler;
39 compat_ulong_t sa_flags;
40 compat_uptr_t sa_restorer;
41 sigset_t sa_mask __packed;
42};
43
44struct compat_sigaltstack {
45 compat_uptr_t ss_sp;
46 int ss_flags;
47 compat_size_t ss_size;
48};
49
50struct compat_ucontext {
51 compat_ulong_t uc_flags;
52 compat_uptr_t uc_link;
53 struct compat_sigaltstack uc_stack;
54 struct sigcontext uc_mcontext;
55 sigset_t uc_sigmask; /* mask last for extensibility */
56};
57
58#define COMPAT_SI_PAD_SIZE ((SI_MAX_SIZE - 3 * sizeof(int)) / sizeof(int))
59
60struct compat_siginfo {
61 int si_signo;
62 int si_errno;
63 int si_code;
64
65 union {
66 int _pad[COMPAT_SI_PAD_SIZE];
67
68 /* kill() */
69 struct {
70 unsigned int _pid; /* sender's pid */
71 unsigned int _uid; /* sender's uid */
72 } _kill;
73
74 /* POSIX.1b timers */
75 struct {
76 compat_timer_t _tid; /* timer id */
77 int _overrun; /* overrun count */
78 compat_sigval_t _sigval; /* same as below */
79 int _sys_private; /* not to be passed to user */
80 int _overrun_incr; /* amount to add to overrun */
81 } _timer;
82
83 /* POSIX.1b signals */
84 struct {
85 unsigned int _pid; /* sender's pid */
86 unsigned int _uid; /* sender's uid */
87 compat_sigval_t _sigval;
88 } _rt;
89
90 /* SIGCHLD */
91 struct {
92 unsigned int _pid; /* which child */
93 unsigned int _uid; /* sender's uid */
94 int _status; /* exit code */
95 compat_clock_t _utime;
96 compat_clock_t _stime;
97 } _sigchld;
98
99 /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
100 struct {
101 unsigned int _addr; /* faulting insn/memory ref. */
102#ifdef __ARCH_SI_TRAPNO
103 int _trapno; /* TRAP # which caused the signal */
104#endif
105 } _sigfault;
106
107 /* SIGPOLL */
108 struct {
109 int _band; /* POLL_IN, POLL_OUT, POLL_MSG */
110 int _fd;
111 } _sigpoll;
112 } _sifields;
113};
114
115struct compat_rt_sigframe {
116 unsigned char save_area[C_ABI_SAVE_AREA_SIZE]; /* caller save area */
117 struct compat_siginfo info;
118 struct compat_ucontext uc;
119};
120
121#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
122
123long compat_sys_rt_sigaction(int sig, struct compat_sigaction __user *act,
124 struct compat_sigaction __user *oact,
125 size_t sigsetsize)
126{
127 struct k_sigaction new_sa, old_sa;
128 int ret = -EINVAL;
129
130 /* XXX: Don't preclude handling different sized sigset_t's. */
131 if (sigsetsize != sizeof(sigset_t))
132 goto out;
133
134 if (act) {
135 compat_uptr_t handler, restorer;
136
137 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
138 __get_user(handler, &act->sa_handler) ||
139 __get_user(new_sa.sa.sa_flags, &act->sa_flags) ||
140 __get_user(restorer, &act->sa_restorer) ||
141 __copy_from_user(&new_sa.sa.sa_mask, &act->sa_mask,
142 sizeof(sigset_t)))
143 return -EFAULT;
144 new_sa.sa.sa_handler = compat_ptr(handler);
145 new_sa.sa.sa_restorer = compat_ptr(restorer);
146 }
147
148 ret = do_sigaction(sig, act ? &new_sa : NULL, oact ? &old_sa : NULL);
149
150 if (!ret && oact) {
151 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
152 __put_user(ptr_to_compat(old_sa.sa.sa_handler),
153 &oact->sa_handler) ||
154 __put_user(ptr_to_compat(old_sa.sa.sa_restorer),
155 &oact->sa_restorer) ||
156 __put_user(old_sa.sa.sa_flags, &oact->sa_flags) ||
157 __copy_to_user(&oact->sa_mask, &old_sa.sa.sa_mask,
158 sizeof(sigset_t)))
159 return -EFAULT;
160 }
161out:
162 return ret;
163}
164
165long compat_sys_rt_sigqueueinfo(int pid, int sig,
166 struct compat_siginfo __user *uinfo)
167{
168 siginfo_t info;
169 int ret;
170 mm_segment_t old_fs = get_fs();
171
172 if (copy_siginfo_from_user32(&info, uinfo))
173 return -EFAULT;
174 set_fs(KERNEL_DS);
175 ret = sys_rt_sigqueueinfo(pid, sig, (siginfo_t __force __user *)&info);
176 set_fs(old_fs);
177 return ret;
178}
179
180int copy_siginfo_to_user32(struct compat_siginfo __user *to, siginfo_t *from)
181{
182 int err;
183
184 if (!access_ok(VERIFY_WRITE, to, sizeof(struct compat_siginfo)))
185 return -EFAULT;
186
187 /* If you change siginfo_t structure, please make sure that
188 this code is fixed accordingly.
189 It should never copy any pad contained in the structure
190 to avoid security leaks, but must copy the generic
191 3 ints plus the relevant union member. */
192 err = __put_user(from->si_signo, &to->si_signo);
193 err |= __put_user(from->si_errno, &to->si_errno);
194 err |= __put_user((short)from->si_code, &to->si_code);
195
196 if (from->si_code < 0) {
197 err |= __put_user(from->si_pid, &to->si_pid);
198 err |= __put_user(from->si_uid, &to->si_uid);
199 err |= __put_user(ptr_to_compat(from->si_ptr), &to->si_ptr);
200 } else {
201 /*
202 * First 32bits of unions are always present:
203 * si_pid === si_band === si_tid === si_addr(LS half)
204 */
205 err |= __put_user(from->_sifields._pad[0],
206 &to->_sifields._pad[0]);
207 switch (from->si_code >> 16) {
208 case __SI_FAULT >> 16:
209 break;
210 case __SI_CHLD >> 16:
211 err |= __put_user(from->si_utime, &to->si_utime);
212 err |= __put_user(from->si_stime, &to->si_stime);
213 err |= __put_user(from->si_status, &to->si_status);
214 /* FALL THROUGH */
215 default:
216 case __SI_KILL >> 16:
217 err |= __put_user(from->si_uid, &to->si_uid);
218 break;
219 case __SI_POLL >> 16:
220 err |= __put_user(from->si_fd, &to->si_fd);
221 break;
222 case __SI_TIMER >> 16:
223 err |= __put_user(from->si_overrun, &to->si_overrun);
224 err |= __put_user(ptr_to_compat(from->si_ptr),
225 &to->si_ptr);
226 break;
227 /* This is not generated by the kernel as of now. */
228 case __SI_RT >> 16:
229 case __SI_MESGQ >> 16:
230 err |= __put_user(from->si_uid, &to->si_uid);
231 err |= __put_user(from->si_int, &to->si_int);
232 break;
233 }
234 }
235 return err;
236}
237
238int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from)
239{
240 int err;
241 u32 ptr32;
242
243 if (!access_ok(VERIFY_READ, from, sizeof(struct compat_siginfo)))
244 return -EFAULT;
245
246 err = __get_user(to->si_signo, &from->si_signo);
247 err |= __get_user(to->si_errno, &from->si_errno);
248 err |= __get_user(to->si_code, &from->si_code);
249
250 err |= __get_user(to->si_pid, &from->si_pid);
251 err |= __get_user(to->si_uid, &from->si_uid);
252 err |= __get_user(ptr32, &from->si_ptr);
253 to->si_ptr = compat_ptr(ptr32);
254
255 return err;
256}
257
258long compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
259 struct compat_sigaltstack __user *uoss_ptr,
260 struct pt_regs *regs)
261{
262 stack_t uss, uoss;
263 int ret;
264 mm_segment_t seg;
265
266 if (uss_ptr) {
267 u32 ptr;
268
269 memset(&uss, 0, sizeof(stack_t));
270 if (!access_ok(VERIFY_READ, uss_ptr, sizeof(*uss_ptr)) ||
271 __get_user(ptr, &uss_ptr->ss_sp) ||
272 __get_user(uss.ss_flags, &uss_ptr->ss_flags) ||
273 __get_user(uss.ss_size, &uss_ptr->ss_size))
274 return -EFAULT;
275 uss.ss_sp = compat_ptr(ptr);
276 }
277 seg = get_fs();
278 set_fs(KERNEL_DS);
279 ret = do_sigaltstack(uss_ptr ? (stack_t __user __force *)&uss : NULL,
280 (stack_t __user __force *)&uoss,
281 (unsigned long)compat_ptr(regs->sp));
282 set_fs(seg);
283 if (ret >= 0 && uoss_ptr) {
284 if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(*uoss_ptr)) ||
285 __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) ||
286 __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) ||
287 __put_user(uoss.ss_size, &uoss_ptr->ss_size))
288 ret = -EFAULT;
289 }
290 return ret;
291}
292
293/* The assembly shim for this function arranges to ignore the return value. */
294long compat_sys_rt_sigreturn(struct pt_regs *regs)
295{
296 struct compat_rt_sigframe __user *frame =
297 (struct compat_rt_sigframe __user *) compat_ptr(regs->sp);
298 sigset_t set;
299
300 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
301 goto badframe;
302 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
303 goto badframe;
304
305 sigdelsetmask(&set, ~_BLOCKABLE);
306 spin_lock_irq(¤t->sighand->siglock);
307 current->blocked = set;
308 recalc_sigpending();
309 spin_unlock_irq(¤t->sighand->siglock);
310
311 if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
312 goto badframe;
313
314 if (compat_sys_sigaltstack(&frame->uc.uc_stack, NULL, regs) != 0)
315 goto badframe;
316
317 return 0;
318
319badframe:
320 signal_fault("bad sigreturn frame", regs, frame, 0);
321 return 0;
322}
323
324/*
325 * Determine which stack to use..
326 */
327static inline void __user *compat_get_sigframe(struct k_sigaction *ka,
328 struct pt_regs *regs,
329 size_t frame_size)
330{
331 unsigned long sp;
332
333 /* Default to using normal stack */
334 sp = (unsigned long)compat_ptr(regs->sp);
335
336 /*
337 * If we are on the alternate signal stack and would overflow
338 * it, don't. Return an always-bogus address instead so we
339 * will die with SIGSEGV.
340 */
341 if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size)))
342 return (void __user __force *)-1UL;
343
344 /* This is the X/Open sanctioned signal stack switching. */
345 if (ka->sa.sa_flags & SA_ONSTACK) {
346 if (sas_ss_flags(sp) == 0)
347 sp = current->sas_ss_sp + current->sas_ss_size;
348 }
349
350 sp -= frame_size;
351 /*
352 * Align the stack pointer according to the TILE ABI,
353 * i.e. so that on function entry (sp & 15) == 0.
354 */
355 sp &= -16UL;
356 return (void __user *) sp;
357}
358
359int compat_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
360 sigset_t *set, struct pt_regs *regs)
361{
362 unsigned long restorer;
363 struct compat_rt_sigframe __user *frame;
364 int err = 0;
365 int usig;
366
367 frame = compat_get_sigframe(ka, regs, sizeof(*frame));
368
369 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
370 goto give_sigsegv;
371
372 usig = current_thread_info()->exec_domain
373 && current_thread_info()->exec_domain->signal_invmap
374 && sig < 32
375 ? current_thread_info()->exec_domain->signal_invmap[sig]
376 : sig;
377
378 /* Always write at least the signal number for the stack backtracer. */
379 if (ka->sa.sa_flags & SA_SIGINFO) {
380 /* At sigreturn time, restore the callee-save registers too. */
381 err |= copy_siginfo_to_user32(&frame->info, info);
382 regs->flags |= PT_FLAGS_RESTORE_REGS;
383 } else {
384 err |= __put_user(info->si_signo, &frame->info.si_signo);
385 }
386
387 /* Create the ucontext. */
388 err |= __clear_user(&frame->save_area, sizeof(frame->save_area));
389 err |= __put_user(0, &frame->uc.uc_flags);
390 err |= __put_user(0, &frame->uc.uc_link);
391 err |= __put_user(ptr_to_compat((void *)(current->sas_ss_sp)),
392 &frame->uc.uc_stack.ss_sp);
393 err |= __put_user(sas_ss_flags(regs->sp),
394 &frame->uc.uc_stack.ss_flags);
395 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
396 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs);
397 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
398 if (err)
399 goto give_sigsegv;
400
401 restorer = VDSO_BASE;
402 if (ka->sa.sa_flags & SA_RESTORER)
403 restorer = ptr_to_compat_reg(ka->sa.sa_restorer);
404
405 /*
406 * Set up registers for signal handler.
407 * Registers that we don't modify keep the value they had from
408 * user-space at the time we took the signal.
409 */
410 regs->pc = ptr_to_compat_reg(ka->sa.sa_handler);
411 regs->ex1 = PL_ICS_EX1(USER_PL, 1); /* set crit sec in handler */
412 regs->sp = ptr_to_compat_reg(frame);
413 regs->lr = restorer;
414 regs->regs[0] = (unsigned long) usig;
415
416 if (ka->sa.sa_flags & SA_SIGINFO) {
417 /* Need extra arguments, so mark to restore caller-saves. */
418 regs->regs[1] = ptr_to_compat_reg(&frame->info);
419 regs->regs[2] = ptr_to_compat_reg(&frame->uc);
420 regs->flags |= PT_FLAGS_CALLER_SAVES;
421 }
422
423 /*
424 * Notify any tracer that was single-stepping it.
425 * The tracer may want to single-step inside the
426 * handler too.
427 */
428 if (test_thread_flag(TIF_SINGLESTEP))
429 ptrace_notify(SIGTRAP);
430
431 return 0;
432
433give_sigsegv:
434 signal_fault("bad setup frame", regs, frame, sig);
435 return -EFAULT;
436}
1/*
2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
12 * more details.
13 */
14
15#include <linux/sched.h>
16#include <linux/mm.h>
17#include <linux/smp.h>
18#include <linux/kernel.h>
19#include <linux/signal.h>
20#include <linux/errno.h>
21#include <linux/wait.h>
22#include <linux/unistd.h>
23#include <linux/stddef.h>
24#include <linux/personality.h>
25#include <linux/suspend.h>
26#include <linux/ptrace.h>
27#include <linux/elf.h>
28#include <linux/compat.h>
29#include <linux/syscalls.h>
30#include <linux/uaccess.h>
31#include <asm/processor.h>
32#include <asm/ucontext.h>
33#include <asm/sigframe.h>
34#include <asm/syscalls.h>
35#include <asm/vdso.h>
36#include <arch/interrupts.h>
37
38struct compat_ucontext {
39 compat_ulong_t uc_flags;
40 compat_uptr_t uc_link;
41 struct compat_sigaltstack uc_stack;
42 struct sigcontext uc_mcontext;
43 sigset_t uc_sigmask; /* mask last for extensibility */
44};
45
46struct compat_rt_sigframe {
47 unsigned char save_area[C_ABI_SAVE_AREA_SIZE]; /* caller save area */
48 struct compat_siginfo info;
49 struct compat_ucontext uc;
50};
51
52int copy_siginfo_to_user32(struct compat_siginfo __user *to, const siginfo_t *from)
53{
54 int err;
55
56 if (!access_ok(VERIFY_WRITE, to, sizeof(struct compat_siginfo)))
57 return -EFAULT;
58
59 /* If you change siginfo_t structure, please make sure that
60 this code is fixed accordingly.
61 It should never copy any pad contained in the structure
62 to avoid security leaks, but must copy the generic
63 3 ints plus the relevant union member. */
64 err = __put_user(from->si_signo, &to->si_signo);
65 err |= __put_user(from->si_errno, &to->si_errno);
66 err |= __put_user((short)from->si_code, &to->si_code);
67
68 if (from->si_code < 0) {
69 err |= __put_user(from->si_pid, &to->si_pid);
70 err |= __put_user(from->si_uid, &to->si_uid);
71 err |= __put_user(from->si_int, &to->si_int);
72 } else {
73 /*
74 * First 32bits of unions are always present:
75 * si_pid === si_band === si_tid === si_addr(LS half)
76 */
77 err |= __put_user(from->_sifields._pad[0],
78 &to->_sifields._pad[0]);
79 switch (from->si_code >> 16) {
80 case __SI_FAULT >> 16:
81 break;
82 case __SI_CHLD >> 16:
83 err |= __put_user(from->si_utime, &to->si_utime);
84 err |= __put_user(from->si_stime, &to->si_stime);
85 err |= __put_user(from->si_status, &to->si_status);
86 /* FALL THROUGH */
87 default:
88 case __SI_KILL >> 16:
89 err |= __put_user(from->si_uid, &to->si_uid);
90 break;
91 case __SI_POLL >> 16:
92 err |= __put_user(from->si_fd, &to->si_fd);
93 break;
94 case __SI_TIMER >> 16:
95 err |= __put_user(from->si_overrun, &to->si_overrun);
96 err |= __put_user(from->si_int, &to->si_int);
97 break;
98 /* This is not generated by the kernel as of now. */
99 case __SI_RT >> 16:
100 case __SI_MESGQ >> 16:
101 err |= __put_user(from->si_uid, &to->si_uid);
102 err |= __put_user(from->si_int, &to->si_int);
103 break;
104 }
105 }
106 return err;
107}
108
109int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from)
110{
111 int err;
112
113 if (!access_ok(VERIFY_READ, from, sizeof(struct compat_siginfo)))
114 return -EFAULT;
115
116 err = __get_user(to->si_signo, &from->si_signo);
117 err |= __get_user(to->si_errno, &from->si_errno);
118 err |= __get_user(to->si_code, &from->si_code);
119
120 err |= __get_user(to->si_pid, &from->si_pid);
121 err |= __get_user(to->si_uid, &from->si_uid);
122 err |= __get_user(to->si_int, &from->si_int);
123
124 return err;
125}
126
127/* The assembly shim for this function arranges to ignore the return value. */
128long compat_sys_rt_sigreturn(void)
129{
130 struct pt_regs *regs = current_pt_regs();
131 struct compat_rt_sigframe __user *frame =
132 (struct compat_rt_sigframe __user *) compat_ptr(regs->sp);
133 sigset_t set;
134
135 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
136 goto badframe;
137 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
138 goto badframe;
139
140 set_current_blocked(&set);
141
142 if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
143 goto badframe;
144
145 if (compat_restore_altstack(&frame->uc.uc_stack))
146 goto badframe;
147
148 return 0;
149
150badframe:
151 signal_fault("bad sigreturn frame", regs, frame, 0);
152 return 0;
153}
154
155/*
156 * Determine which stack to use..
157 */
158static inline void __user *compat_get_sigframe(struct k_sigaction *ka,
159 struct pt_regs *regs,
160 size_t frame_size)
161{
162 unsigned long sp;
163
164 /* Default to using normal stack */
165 sp = (unsigned long)compat_ptr(regs->sp);
166
167 /*
168 * If we are on the alternate signal stack and would overflow
169 * it, don't. Return an always-bogus address instead so we
170 * will die with SIGSEGV.
171 */
172 if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size)))
173 return (void __user __force *)-1UL;
174
175 /* This is the X/Open sanctioned signal stack switching. */
176 if (ka->sa.sa_flags & SA_ONSTACK) {
177 if (sas_ss_flags(sp) == 0)
178 sp = current->sas_ss_sp + current->sas_ss_size;
179 }
180
181 sp -= frame_size;
182 /*
183 * Align the stack pointer according to the TILE ABI,
184 * i.e. so that on function entry (sp & 15) == 0.
185 */
186 sp &= -16UL;
187 return (void __user *) sp;
188}
189
190int compat_setup_rt_frame(struct ksignal *ksig, sigset_t *set,
191 struct pt_regs *regs)
192{
193 unsigned long restorer;
194 struct compat_rt_sigframe __user *frame;
195 int err = 0, sig = ksig->sig;
196
197 frame = compat_get_sigframe(&ksig->ka, regs, sizeof(*frame));
198
199 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
200 goto err;
201
202 /* Always write at least the signal number for the stack backtracer. */
203 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
204 /* At sigreturn time, restore the callee-save registers too. */
205 err |= copy_siginfo_to_user32(&frame->info, &ksig->info);
206 regs->flags |= PT_FLAGS_RESTORE_REGS;
207 } else {
208 err |= __put_user(ksig->info.si_signo, &frame->info.si_signo);
209 }
210
211 /* Create the ucontext. */
212 err |= __clear_user(&frame->save_area, sizeof(frame->save_area));
213 err |= __put_user(0, &frame->uc.uc_flags);
214 err |= __put_user(0, &frame->uc.uc_link);
215 err |= __compat_save_altstack(&frame->uc.uc_stack, regs->sp);
216 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs);
217 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
218 if (err)
219 goto err;
220
221 restorer = VDSO_SYM(&__vdso_rt_sigreturn);
222 if (ksig->ka.sa.sa_flags & SA_RESTORER)
223 restorer = ptr_to_compat_reg(ksig->ka.sa.sa_restorer);
224
225 /*
226 * Set up registers for signal handler.
227 * Registers that we don't modify keep the value they had from
228 * user-space at the time we took the signal.
229 * We always pass siginfo and mcontext, regardless of SA_SIGINFO,
230 * since some things rely on this (e.g. glibc's debug/segfault.c).
231 */
232 regs->pc = ptr_to_compat_reg(ksig->ka.sa.sa_handler);
233 regs->ex1 = PL_ICS_EX1(USER_PL, 1); /* set crit sec in handler */
234 regs->sp = ptr_to_compat_reg(frame);
235 regs->lr = restorer;
236 regs->regs[0] = (unsigned long) sig;
237 regs->regs[1] = ptr_to_compat_reg(&frame->info);
238 regs->regs[2] = ptr_to_compat_reg(&frame->uc);
239 regs->flags |= PT_FLAGS_CALLER_SAVES;
240 return 0;
241
242err:
243 trace_unhandled_signal("bad sigreturn frame", regs,
244 (unsigned long)frame, SIGSEGV);
245 return -EFAULT;
246}