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13#include <linux/sched.h>
14#include <linux/mm.h>
15#include <linux/smp.h>
16#include <linux/kernel.h>
17#include <linux/signal.h>
18#include <linux/errno.h>
19#include <linux/wait.h>
20#include <linux/unistd.h>
21#include <linux/stddef.h>
22#include <linux/personality.h>
23#include <linux/freezer.h>
24#include <linux/tracehook.h>
25#include <asm/cacheflush.h>
26#include <asm/ucontext.h>
27#include <asm/uaccess.h>
28
29#define DEBUG_SIG 0
30
31#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
32
33int do_signal(struct pt_regs *, sigset_t *);
34
35asmlinkage int
36sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize,
37 unsigned long r2, unsigned long r3, unsigned long r4,
38 unsigned long r5, unsigned long r6, struct pt_regs *regs)
39{
40 sigset_t newset;
41
42
43 if (sigsetsize != sizeof(sigset_t))
44 return -EINVAL;
45
46 if (copy_from_user(&newset, unewset, sizeof(newset)))
47 return -EFAULT;
48 sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
49
50 spin_lock_irq(¤t->sighand->siglock);
51 current->saved_sigmask = current->blocked;
52 current->blocked = newset;
53 recalc_sigpending();
54 spin_unlock_irq(¤t->sighand->siglock);
55
56 current->state = TASK_INTERRUPTIBLE;
57 schedule();
58 set_thread_flag(TIF_RESTORE_SIGMASK);
59 return -ERESTARTNOHAND;
60}
61
62asmlinkage int
63sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
64 unsigned long r2, unsigned long r3, unsigned long r4,
65 unsigned long r5, unsigned long r6, struct pt_regs *regs)
66{
67 return do_sigaltstack(uss, uoss, regs->spu);
68}
69
70
71
72
73
74
75struct rt_sigframe
76{
77 int sig;
78 struct siginfo __user *pinfo;
79 void __user *puc;
80 struct siginfo info;
81 struct ucontext uc;
82
83};
84
85static int
86restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
87 int *r0_p)
88{
89 unsigned int err = 0;
90
91
92 current_thread_info()->restart_block.fn = do_no_restart_syscall;
93
94#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x)
95 COPY(r4);
96 COPY(r5);
97 COPY(r6);
98 COPY(pt_regs);
99
100 COPY(r1);
101 COPY(r2);
102 COPY(r3);
103 COPY(r7);
104 COPY(r8);
105 COPY(r9);
106 COPY(r10);
107 COPY(r11);
108 COPY(r12);
109 COPY(acc0h);
110 COPY(acc0l);
111 COPY(acc1h);
112 COPY(acc1l);
113 COPY(psw);
114 COPY(bpc);
115 COPY(bbpsw);
116 COPY(bbpc);
117 COPY(spu);
118 COPY(fp);
119 COPY(lr);
120 COPY(spi);
121#undef COPY
122
123 regs->syscall_nr = -1;
124 err |= __get_user(*r0_p, &sc->sc_r0);
125
126 return err;
127}
128
129asmlinkage int
130sys_rt_sigreturn(unsigned long r0, unsigned long r1,
131 unsigned long r2, unsigned long r3, unsigned long r4,
132 unsigned long r5, unsigned long r6, struct pt_regs *regs)
133{
134 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->spu;
135 sigset_t set;
136 int result;
137
138 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
139 goto badframe;
140 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
141 goto badframe;
142
143 sigdelsetmask(&set, ~_BLOCKABLE);
144 spin_lock_irq(¤t->sighand->siglock);
145 current->blocked = set;
146 recalc_sigpending();
147 spin_unlock_irq(¤t->sighand->siglock);
148
149 if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &result))
150 goto badframe;
151
152 if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->spu) == -EFAULT)
153 goto badframe;
154
155 return result;
156
157badframe:
158 force_sig(SIGSEGV, current);
159 return 0;
160}
161
162
163
164
165
166static int
167setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
168 unsigned long mask)
169{
170 int err = 0;
171
172#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
173 COPY(r4);
174 COPY(r5);
175 COPY(r6);
176 COPY(pt_regs);
177 COPY(r0);
178 COPY(r1);
179 COPY(r2);
180 COPY(r3);
181 COPY(r7);
182 COPY(r8);
183 COPY(r9);
184 COPY(r10);
185 COPY(r11);
186 COPY(r12);
187 COPY(acc0h);
188 COPY(acc0l);
189 COPY(acc1h);
190 COPY(acc1l);
191 COPY(psw);
192 COPY(bpc);
193 COPY(bbpsw);
194 COPY(bbpc);
195 COPY(spu);
196 COPY(fp);
197 COPY(lr);
198 COPY(spi);
199#undef COPY
200
201 err |= __put_user(mask, &sc->oldmask);
202
203 return err;
204}
205
206
207
208
209static inline void __user *
210get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
211{
212
213 if (ka->sa.sa_flags & SA_ONSTACK) {
214 if (sas_ss_flags(sp) == 0)
215 sp = current->sas_ss_sp + current->sas_ss_size;
216 }
217
218 return (void __user *)((sp - frame_size) & -8ul);
219}
220
221static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
222 sigset_t *set, struct pt_regs *regs)
223{
224 struct rt_sigframe __user *frame;
225 int err = 0;
226 int signal;
227
228 frame = get_sigframe(ka, regs->spu, sizeof(*frame));
229
230 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
231 goto give_sigsegv;
232
233 signal = current_thread_info()->exec_domain
234 && current_thread_info()->exec_domain->signal_invmap
235 && sig < 32
236 ? current_thread_info()->exec_domain->signal_invmap[sig]
237 : sig;
238
239 err |= __put_user(signal, &frame->sig);
240 if (err)
241 goto give_sigsegv;
242
243 err |= __put_user(&frame->info, &frame->pinfo);
244 err |= __put_user(&frame->uc, &frame->puc);
245 err |= copy_siginfo_to_user(&frame->info, info);
246 if (err)
247 goto give_sigsegv;
248
249
250 err |= __put_user(0, &frame->uc.uc_flags);
251 err |= __put_user(0, &frame->uc.uc_link);
252 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
253 err |= __put_user(sas_ss_flags(regs->spu),
254 &frame->uc.uc_stack.ss_flags);
255 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
256 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);
257 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
258 if (err)
259 goto give_sigsegv;
260
261
262 regs->lr = (unsigned long)ka->sa.sa_restorer;
263
264
265 regs->spu = (unsigned long)frame;
266 regs->r0 = signal;
267 regs->r1 = (unsigned long)&frame->info;
268 regs->r2 = (unsigned long)&frame->uc;
269 regs->bpc = (unsigned long)ka->sa.sa_handler;
270
271 set_fs(USER_DS);
272
273#if DEBUG_SIG
274 printk("SIG deliver (%s:%d): sp=%p pc=%p\n",
275 current->comm, current->pid, frame, regs->pc);
276#endif
277
278 return;
279
280give_sigsegv:
281 force_sigsegv(sig, current);
282}
283
284
285
286
287
288static void
289handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
290 sigset_t *oldset, struct pt_regs *regs)
291{
292 unsigned short inst;
293
294
295 if (regs->syscall_nr >= 0) {
296
297 switch (regs->r0) {
298 case -ERESTART_RESTARTBLOCK:
299 case -ERESTARTNOHAND:
300 regs->r0 = -EINTR;
301 break;
302
303 case -ERESTARTSYS:
304 if (!(ka->sa.sa_flags & SA_RESTART)) {
305 regs->r0 = -EINTR;
306 break;
307 }
308
309 case -ERESTARTNOINTR:
310 regs->r0 = regs->orig_r0;
311 inst = *(unsigned short *)(regs->bpc - 2);
312 if ((inst & 0xfff0) == 0x10f0)
313 regs->bpc -= 2;
314 else
315 regs->bpc -= 4;
316 }
317 }
318
319
320 setup_rt_frame(sig, ka, info, oldset, regs);
321
322 spin_lock_irq(¤t->sighand->siglock);
323 sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
324 if (!(ka->sa.sa_flags & SA_NODEFER))
325 sigaddset(¤t->blocked,sig);
326 recalc_sigpending();
327 spin_unlock_irq(¤t->sighand->siglock);
328}
329
330
331
332
333
334
335int do_signal(struct pt_regs *regs, sigset_t *oldset)
336{
337 siginfo_t info;
338 int signr;
339 struct k_sigaction ka;
340 unsigned short inst;
341
342
343
344
345
346
347
348 if (!user_mode(regs))
349 return 1;
350
351 if (try_to_freeze())
352 goto no_signal;
353
354 if (!oldset)
355 oldset = ¤t->blocked;
356
357 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
358 if (signr > 0) {
359
360
361
362
363
364
365
366 handle_signal(signr, &ka, &info, oldset, regs);
367 return 1;
368 }
369
370 no_signal:
371
372 if (regs->syscall_nr >= 0) {
373
374 if (regs->r0 == -ERESTARTNOHAND ||
375 regs->r0 == -ERESTARTSYS ||
376 regs->r0 == -ERESTARTNOINTR) {
377 regs->r0 = regs->orig_r0;
378 inst = *(unsigned short *)(regs->bpc - 2);
379 if ((inst & 0xfff0) == 0x10f0)
380 regs->bpc -= 2;
381 else
382 regs->bpc -= 4;
383 }
384 if (regs->r0 == -ERESTART_RESTARTBLOCK){
385 regs->r0 = regs->orig_r0;
386 regs->r7 = __NR_restart_syscall;
387 inst = *(unsigned short *)(regs->bpc - 2);
388 if ((inst & 0xfff0) == 0x10f0)
389 regs->bpc -= 2;
390 else
391 regs->bpc -= 4;
392 }
393 }
394 return 0;
395}
396
397
398
399
400
401void do_notify_resume(struct pt_regs *regs, sigset_t *oldset,
402 __u32 thread_info_flags)
403{
404
405 if (thread_info_flags & _TIF_SINGLESTEP)
406 clear_thread_flag(TIF_SINGLESTEP);
407
408
409 if (thread_info_flags & _TIF_SIGPENDING)
410 do_signal(regs,oldset);
411
412 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
413 clear_thread_flag(TIF_NOTIFY_RESUME);
414 tracehook_notify_resume(regs);
415 if (current->replacement_session_keyring)
416 key_replace_session_keyring();
417 }
418
419 clear_thread_flag(TIF_IRET);
420}
421