Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/arm/kernel/signal.c | |
3 | * | |
4 | * Copyright (C) 1995-2002 Russell King | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
1da177e4 LT |
10 | #include <linux/errno.h> |
11 | #include <linux/signal.h> | |
12 | #include <linux/ptrace.h> | |
13 | #include <linux/personality.h> | |
7dfb7103 | 14 | #include <linux/freezer.h> |
1da177e4 LT |
15 | |
16 | #include <asm/cacheflush.h> | |
17 | #include <asm/ucontext.h> | |
18 | #include <asm/uaccess.h> | |
19 | #include <asm/unistd.h> | |
20 | ||
21 | #include "ptrace.h" | |
e00d349e | 22 | #include "signal.h" |
1da177e4 LT |
23 | |
24 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
25 | ||
26 | /* | |
27 | * For ARM syscalls, we encode the syscall number into the instruction. | |
28 | */ | |
29 | #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)) | |
30 | #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)) | |
31 | ||
fcca538b NP |
32 | /* |
33 | * With EABI, the syscall number has to be loaded into r7. | |
34 | */ | |
35 | #define MOV_R7_NR_SIGRETURN (0xe3a07000 | (__NR_sigreturn - __NR_SYSCALL_BASE)) | |
36 | #define MOV_R7_NR_RT_SIGRETURN (0xe3a07000 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) | |
37 | ||
1da177e4 LT |
38 | /* |
39 | * For Thumb syscalls, we pass the syscall number via r7. We therefore | |
40 | * need two 16-bit instructions. | |
41 | */ | |
42 | #define SWI_THUMB_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_sigreturn - __NR_SYSCALL_BASE)) | |
43 | #define SWI_THUMB_RT_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) | |
44 | ||
fcca538b NP |
45 | const unsigned long sigreturn_codes[7] = { |
46 | MOV_R7_NR_SIGRETURN, SWI_SYS_SIGRETURN, SWI_THUMB_SIGRETURN, | |
47 | MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN, | |
1da177e4 LT |
48 | }; |
49 | ||
50 | static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall); | |
51 | ||
52 | /* | |
53 | * atomically swap in the new signal mask, and wait for a signal. | |
54 | */ | |
55 | asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask, struct pt_regs *regs) | |
56 | { | |
57 | sigset_t saveset; | |
58 | ||
59 | mask &= _BLOCKABLE; | |
60 | spin_lock_irq(¤t->sighand->siglock); | |
61 | saveset = current->blocked; | |
62 | siginitset(¤t->blocked, mask); | |
63 | recalc_sigpending(); | |
64 | spin_unlock_irq(¤t->sighand->siglock); | |
65 | regs->ARM_r0 = -EINTR; | |
66 | ||
67 | while (1) { | |
68 | current->state = TASK_INTERRUPTIBLE; | |
69 | schedule(); | |
70 | if (do_signal(&saveset, regs, 0)) | |
71 | return regs->ARM_r0; | |
72 | } | |
73 | } | |
74 | ||
75 | asmlinkage int | |
76 | sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, struct pt_regs *regs) | |
77 | { | |
78 | sigset_t saveset, newset; | |
79 | ||
80 | /* XXX: Don't preclude handling different sized sigset_t's. */ | |
81 | if (sigsetsize != sizeof(sigset_t)) | |
82 | return -EINVAL; | |
83 | ||
84 | if (copy_from_user(&newset, unewset, sizeof(newset))) | |
85 | return -EFAULT; | |
86 | sigdelsetmask(&newset, ~_BLOCKABLE); | |
87 | ||
88 | spin_lock_irq(¤t->sighand->siglock); | |
89 | saveset = current->blocked; | |
90 | current->blocked = newset; | |
91 | recalc_sigpending(); | |
92 | spin_unlock_irq(¤t->sighand->siglock); | |
93 | regs->ARM_r0 = -EINTR; | |
94 | ||
95 | while (1) { | |
96 | current->state = TASK_INTERRUPTIBLE; | |
97 | schedule(); | |
98 | if (do_signal(&saveset, regs, 0)) | |
99 | return regs->ARM_r0; | |
100 | } | |
101 | } | |
102 | ||
103 | asmlinkage int | |
104 | sys_sigaction(int sig, const struct old_sigaction __user *act, | |
105 | struct old_sigaction __user *oact) | |
106 | { | |
107 | struct k_sigaction new_ka, old_ka; | |
108 | int ret; | |
109 | ||
110 | if (act) { | |
111 | old_sigset_t mask; | |
112 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | |
113 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
114 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | |
115 | return -EFAULT; | |
116 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); | |
117 | __get_user(mask, &act->sa_mask); | |
118 | siginitset(&new_ka.sa.sa_mask, mask); | |
119 | } | |
120 | ||
121 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
122 | ||
123 | if (!ret && oact) { | |
124 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
125 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
126 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | |
127 | return -EFAULT; | |
128 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); | |
129 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
130 | } | |
131 | ||
132 | return ret; | |
133 | } | |
134 | ||
3bec6ded LB |
135 | #ifdef CONFIG_CRUNCH |
136 | static int preserve_crunch_context(struct crunch_sigframe *frame) | |
137 | { | |
138 | char kbuf[sizeof(*frame) + 8]; | |
139 | struct crunch_sigframe *kframe; | |
140 | ||
141 | /* the crunch context must be 64 bit aligned */ | |
142 | kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
143 | kframe->magic = CRUNCH_MAGIC; | |
144 | kframe->size = CRUNCH_STORAGE_SIZE; | |
145 | crunch_task_copy(current_thread_info(), &kframe->storage); | |
146 | return __copy_to_user(frame, kframe, sizeof(*frame)); | |
147 | } | |
148 | ||
149 | static int restore_crunch_context(struct crunch_sigframe *frame) | |
150 | { | |
151 | char kbuf[sizeof(*frame) + 8]; | |
152 | struct crunch_sigframe *kframe; | |
153 | ||
154 | /* the crunch context must be 64 bit aligned */ | |
155 | kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
156 | if (__copy_from_user(kframe, frame, sizeof(*frame))) | |
157 | return -1; | |
158 | if (kframe->magic != CRUNCH_MAGIC || | |
159 | kframe->size != CRUNCH_STORAGE_SIZE) | |
160 | return -1; | |
161 | crunch_task_restore(current_thread_info(), &kframe->storage); | |
162 | return 0; | |
163 | } | |
164 | #endif | |
165 | ||
1da177e4 LT |
166 | #ifdef CONFIG_IWMMXT |
167 | ||
1da177e4 LT |
168 | static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame) |
169 | { | |
69b04754 HD |
170 | char kbuf[sizeof(*frame) + 8]; |
171 | struct iwmmxt_sigframe *kframe; | |
1da177e4 LT |
172 | |
173 | /* the iWMMXt context must be 64 bit aligned */ | |
69b04754 | 174 | kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); |
85fe0681 DJ |
175 | kframe->magic = IWMMXT_MAGIC; |
176 | kframe->size = IWMMXT_STORAGE_SIZE; | |
69b04754 HD |
177 | iwmmxt_task_copy(current_thread_info(), &kframe->storage); |
178 | return __copy_to_user(frame, kframe, sizeof(*frame)); | |
1da177e4 LT |
179 | } |
180 | ||
181 | static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame) | |
182 | { | |
69b04754 HD |
183 | char kbuf[sizeof(*frame) + 8]; |
184 | struct iwmmxt_sigframe *kframe; | |
185 | ||
186 | /* the iWMMXt context must be 64 bit aligned */ | |
187 | kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
188 | if (__copy_from_user(kframe, frame, sizeof(*frame))) | |
189 | return -1; | |
85fe0681 DJ |
190 | if (kframe->magic != IWMMXT_MAGIC || |
191 | kframe->size != IWMMXT_STORAGE_SIZE) | |
69b04754 HD |
192 | return -1; |
193 | iwmmxt_task_restore(current_thread_info(), &kframe->storage); | |
194 | return 0; | |
1da177e4 LT |
195 | } |
196 | ||
197 | #endif | |
198 | ||
1da177e4 LT |
199 | /* |
200 | * Do a signal return; undo the signal stack. These are aligned to 64-bit. | |
201 | */ | |
202 | struct sigframe { | |
7d4fdc19 | 203 | struct ucontext uc; |
fcca538b | 204 | unsigned long retcode[2]; |
1da177e4 LT |
205 | }; |
206 | ||
207 | struct rt_sigframe { | |
1da177e4 | 208 | struct siginfo info; |
cb3504e8 | 209 | struct sigframe sig; |
1da177e4 LT |
210 | }; |
211 | ||
68071484 | 212 | static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf) |
1da177e4 | 213 | { |
85fe0681 | 214 | struct aux_sigframe __user *aux; |
68071484 RK |
215 | sigset_t set; |
216 | int err; | |
217 | ||
218 | err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); | |
219 | if (err == 0) { | |
220 | sigdelsetmask(&set, ~_BLOCKABLE); | |
221 | spin_lock_irq(¤t->sighand->siglock); | |
222 | current->blocked = set; | |
223 | recalc_sigpending(); | |
224 | spin_unlock_irq(¤t->sighand->siglock); | |
225 | } | |
1da177e4 | 226 | |
68071484 RK |
227 | __get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); |
228 | __get_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); | |
229 | __get_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); | |
230 | __get_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); | |
231 | __get_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); | |
232 | __get_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); | |
233 | __get_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); | |
234 | __get_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); | |
235 | __get_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); | |
236 | __get_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); | |
237 | __get_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); | |
238 | __get_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); | |
239 | __get_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); | |
240 | __get_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); | |
241 | __get_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); | |
242 | __get_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); | |
243 | __get_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); | |
1da177e4 LT |
244 | |
245 | err |= !valid_user_regs(regs); | |
246 | ||
85fe0681 | 247 | aux = (struct aux_sigframe __user *) sf->uc.uc_regspace; |
3bec6ded LB |
248 | #ifdef CONFIG_CRUNCH |
249 | if (err == 0) | |
250 | err |= restore_crunch_context(&aux->crunch); | |
251 | #endif | |
1da177e4 LT |
252 | #ifdef CONFIG_IWMMXT |
253 | if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) | |
254 | err |= restore_iwmmxt_context(&aux->iwmmxt); | |
255 | #endif | |
256 | #ifdef CONFIG_VFP | |
257 | // if (err == 0) | |
68071484 | 258 | // err |= vfp_restore_state(&sf->aux.vfp); |
1da177e4 LT |
259 | #endif |
260 | ||
261 | return err; | |
262 | } | |
263 | ||
264 | asmlinkage int sys_sigreturn(struct pt_regs *regs) | |
265 | { | |
266 | struct sigframe __user *frame; | |
1da177e4 LT |
267 | |
268 | /* Always make any pending restarted system calls return -EINTR */ | |
269 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
270 | ||
271 | /* | |
272 | * Since we stacked the signal on a 64-bit boundary, | |
273 | * then 'sp' should be word aligned here. If it's | |
274 | * not, then the user is trying to mess with us. | |
275 | */ | |
276 | if (regs->ARM_sp & 7) | |
277 | goto badframe; | |
278 | ||
279 | frame = (struct sigframe __user *)regs->ARM_sp; | |
280 | ||
281 | if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) | |
282 | goto badframe; | |
1da177e4 | 283 | |
68071484 | 284 | if (restore_sigframe(regs, frame)) |
1da177e4 LT |
285 | goto badframe; |
286 | ||
287 | /* Send SIGTRAP if we're single-stepping */ | |
288 | if (current->ptrace & PT_SINGLESTEP) { | |
289 | ptrace_cancel_bpt(current); | |
290 | send_sig(SIGTRAP, current, 1); | |
291 | } | |
292 | ||
293 | return regs->ARM_r0; | |
294 | ||
295 | badframe: | |
296 | force_sig(SIGSEGV, current); | |
297 | return 0; | |
298 | } | |
299 | ||
300 | asmlinkage int sys_rt_sigreturn(struct pt_regs *regs) | |
301 | { | |
302 | struct rt_sigframe __user *frame; | |
1da177e4 LT |
303 | |
304 | /* Always make any pending restarted system calls return -EINTR */ | |
305 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
306 | ||
307 | /* | |
308 | * Since we stacked the signal on a 64-bit boundary, | |
309 | * then 'sp' should be word aligned here. If it's | |
310 | * not, then the user is trying to mess with us. | |
311 | */ | |
312 | if (regs->ARM_sp & 7) | |
313 | goto badframe; | |
314 | ||
315 | frame = (struct rt_sigframe __user *)regs->ARM_sp; | |
316 | ||
317 | if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) | |
318 | goto badframe; | |
1da177e4 | 319 | |
68071484 | 320 | if (restore_sigframe(regs, &frame->sig)) |
1da177e4 LT |
321 | goto badframe; |
322 | ||
cb3504e8 | 323 | if (do_sigaltstack(&frame->sig.uc.uc_stack, NULL, regs->ARM_sp) == -EFAULT) |
1da177e4 LT |
324 | goto badframe; |
325 | ||
326 | /* Send SIGTRAP if we're single-stepping */ | |
327 | if (current->ptrace & PT_SINGLESTEP) { | |
328 | ptrace_cancel_bpt(current); | |
329 | send_sig(SIGTRAP, current, 1); | |
330 | } | |
331 | ||
332 | return regs->ARM_r0; | |
333 | ||
334 | badframe: | |
335 | force_sig(SIGSEGV, current); | |
336 | return 0; | |
337 | } | |
338 | ||
339 | static int | |
aca6ca10 | 340 | setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set) |
1da177e4 | 341 | { |
85fe0681 | 342 | struct aux_sigframe __user *aux; |
1da177e4 LT |
343 | int err = 0; |
344 | ||
aca6ca10 RK |
345 | __put_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); |
346 | __put_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); | |
347 | __put_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); | |
348 | __put_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); | |
349 | __put_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); | |
350 | __put_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); | |
351 | __put_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); | |
352 | __put_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); | |
353 | __put_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); | |
354 | __put_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); | |
355 | __put_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); | |
356 | __put_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); | |
357 | __put_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); | |
358 | __put_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); | |
359 | __put_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); | |
360 | __put_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); | |
361 | __put_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); | |
362 | ||
363 | __put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no, err); | |
364 | __put_user_error(current->thread.error_code, &sf->uc.uc_mcontext.error_code, err); | |
365 | __put_user_error(current->thread.address, &sf->uc.uc_mcontext.fault_address, err); | |
366 | __put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err); | |
367 | ||
368 | err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set)); | |
1da177e4 | 369 | |
85fe0681 | 370 | aux = (struct aux_sigframe __user *) sf->uc.uc_regspace; |
3bec6ded LB |
371 | #ifdef CONFIG_CRUNCH |
372 | if (err == 0) | |
373 | err |= preserve_crunch_context(&aux->crunch); | |
374 | #endif | |
1da177e4 LT |
375 | #ifdef CONFIG_IWMMXT |
376 | if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) | |
377 | err |= preserve_iwmmxt_context(&aux->iwmmxt); | |
378 | #endif | |
379 | #ifdef CONFIG_VFP | |
380 | // if (err == 0) | |
aca6ca10 | 381 | // err |= vfp_save_state(&sf->aux.vfp); |
1da177e4 | 382 | #endif |
85fe0681 | 383 | __put_user_error(0, &aux->end_magic, err); |
1da177e4 LT |
384 | |
385 | return err; | |
386 | } | |
387 | ||
388 | static inline void __user * | |
389 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, int framesize) | |
390 | { | |
391 | unsigned long sp = regs->ARM_sp; | |
392 | void __user *frame; | |
393 | ||
394 | /* | |
395 | * This is the X/Open sanctioned signal stack switching. | |
396 | */ | |
397 | if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp)) | |
398 | sp = current->sas_ss_sp + current->sas_ss_size; | |
399 | ||
400 | /* | |
401 | * ATPCS B01 mandates 8-byte alignment | |
402 | */ | |
403 | frame = (void __user *)((sp - framesize) & ~7); | |
404 | ||
405 | /* | |
406 | * Check that we can actually write to the signal frame. | |
407 | */ | |
408 | if (!access_ok(VERIFY_WRITE, frame, framesize)) | |
409 | frame = NULL; | |
410 | ||
411 | return frame; | |
412 | } | |
413 | ||
414 | static int | |
415 | setup_return(struct pt_regs *regs, struct k_sigaction *ka, | |
416 | unsigned long __user *rc, void __user *frame, int usig) | |
417 | { | |
418 | unsigned long handler = (unsigned long)ka->sa.sa_handler; | |
419 | unsigned long retcode; | |
420 | int thumb = 0; | |
421 | unsigned long cpsr = regs->ARM_cpsr & ~PSR_f; | |
422 | ||
423 | /* | |
424 | * Maybe we need to deliver a 32-bit signal to a 26-bit task. | |
425 | */ | |
426 | if (ka->sa.sa_flags & SA_THIRTYTWO) | |
427 | cpsr = (cpsr & ~MODE_MASK) | USR_MODE; | |
428 | ||
429 | #ifdef CONFIG_ARM_THUMB | |
430 | if (elf_hwcap & HWCAP_THUMB) { | |
431 | /* | |
432 | * The LSB of the handler determines if we're going to | |
433 | * be using THUMB or ARM mode for this signal handler. | |
434 | */ | |
435 | thumb = handler & 1; | |
436 | ||
437 | if (thumb) | |
438 | cpsr |= PSR_T_BIT; | |
439 | else | |
440 | cpsr &= ~PSR_T_BIT; | |
441 | } | |
442 | #endif | |
443 | ||
444 | if (ka->sa.sa_flags & SA_RESTORER) { | |
445 | retcode = (unsigned long)ka->sa.sa_restorer; | |
446 | } else { | |
fcca538b | 447 | unsigned int idx = thumb << 1; |
1da177e4 LT |
448 | |
449 | if (ka->sa.sa_flags & SA_SIGINFO) | |
fcca538b | 450 | idx += 3; |
1da177e4 | 451 | |
fcca538b NP |
452 | if (__put_user(sigreturn_codes[idx], rc) || |
453 | __put_user(sigreturn_codes[idx+1], rc+1)) | |
1da177e4 LT |
454 | return 1; |
455 | ||
e00d349e RK |
456 | if (cpsr & MODE32_BIT) { |
457 | /* | |
458 | * 32-bit code can use the new high-page | |
459 | * signal return code support. | |
460 | */ | |
461 | retcode = KERN_SIGRETURN_CODE + (idx << 2) + thumb; | |
462 | } else { | |
463 | /* | |
464 | * Ensure that the instruction cache sees | |
465 | * the return code written onto the stack. | |
466 | */ | |
467 | flush_icache_range((unsigned long)rc, | |
fcca538b | 468 | (unsigned long)(rc + 2)); |
e00d349e RK |
469 | |
470 | retcode = ((unsigned long)rc) + thumb; | |
471 | } | |
1da177e4 LT |
472 | } |
473 | ||
474 | regs->ARM_r0 = usig; | |
475 | regs->ARM_sp = (unsigned long)frame; | |
476 | regs->ARM_lr = retcode; | |
477 | regs->ARM_pc = handler; | |
478 | regs->ARM_cpsr = cpsr; | |
479 | ||
480 | return 0; | |
481 | } | |
482 | ||
483 | static int | |
484 | setup_frame(int usig, struct k_sigaction *ka, sigset_t *set, struct pt_regs *regs) | |
485 | { | |
486 | struct sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame)); | |
487 | int err = 0; | |
488 | ||
489 | if (!frame) | |
490 | return 1; | |
491 | ||
ca195cfe RK |
492 | /* |
493 | * Set uc.uc_flags to a value which sc.trap_no would never have. | |
494 | */ | |
495 | __put_user_error(0x5ac3c35a, &frame->uc.uc_flags, err); | |
1da177e4 | 496 | |
aca6ca10 | 497 | err |= setup_sigframe(frame, regs, set); |
1da177e4 | 498 | if (err == 0) |
fcca538b | 499 | err = setup_return(regs, ka, frame->retcode, frame, usig); |
1da177e4 LT |
500 | |
501 | return err; | |
502 | } | |
503 | ||
504 | static int | |
505 | setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info, | |
506 | sigset_t *set, struct pt_regs *regs) | |
507 | { | |
508 | struct rt_sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame)); | |
509 | stack_t stack; | |
510 | int err = 0; | |
511 | ||
512 | if (!frame) | |
513 | return 1; | |
514 | ||
1da177e4 LT |
515 | err |= copy_siginfo_to_user(&frame->info, info); |
516 | ||
cb3504e8 RK |
517 | __put_user_error(0, &frame->sig.uc.uc_flags, err); |
518 | __put_user_error(NULL, &frame->sig.uc.uc_link, err); | |
1da177e4 LT |
519 | |
520 | memset(&stack, 0, sizeof(stack)); | |
521 | stack.ss_sp = (void __user *)current->sas_ss_sp; | |
522 | stack.ss_flags = sas_ss_flags(regs->ARM_sp); | |
523 | stack.ss_size = current->sas_ss_size; | |
cb3504e8 | 524 | err |= __copy_to_user(&frame->sig.uc.uc_stack, &stack, sizeof(stack)); |
1da177e4 | 525 | |
aca6ca10 | 526 | err |= setup_sigframe(&frame->sig, regs, set); |
1da177e4 | 527 | if (err == 0) |
cb3504e8 | 528 | err = setup_return(regs, ka, frame->sig.retcode, frame, usig); |
1da177e4 LT |
529 | |
530 | if (err == 0) { | |
531 | /* | |
532 | * For realtime signals we must also set the second and third | |
533 | * arguments for the signal handler. | |
534 | * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06 | |
535 | */ | |
536 | regs->ARM_r1 = (unsigned long)&frame->info; | |
cb3504e8 | 537 | regs->ARM_r2 = (unsigned long)&frame->sig.uc; |
1da177e4 LT |
538 | } |
539 | ||
540 | return err; | |
541 | } | |
542 | ||
543 | static inline void restart_syscall(struct pt_regs *regs) | |
544 | { | |
545 | regs->ARM_r0 = regs->ARM_ORIG_r0; | |
546 | regs->ARM_pc -= thumb_mode(regs) ? 2 : 4; | |
547 | } | |
548 | ||
549 | /* | |
550 | * OK, we're invoking a handler | |
551 | */ | |
552 | static void | |
553 | handle_signal(unsigned long sig, struct k_sigaction *ka, | |
554 | siginfo_t *info, sigset_t *oldset, | |
555 | struct pt_regs * regs, int syscall) | |
556 | { | |
557 | struct thread_info *thread = current_thread_info(); | |
558 | struct task_struct *tsk = current; | |
559 | int usig = sig; | |
560 | int ret; | |
561 | ||
562 | /* | |
563 | * If we were from a system call, check for system call restarting... | |
564 | */ | |
565 | if (syscall) { | |
566 | switch (regs->ARM_r0) { | |
567 | case -ERESTART_RESTARTBLOCK: | |
568 | case -ERESTARTNOHAND: | |
569 | regs->ARM_r0 = -EINTR; | |
570 | break; | |
571 | case -ERESTARTSYS: | |
572 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
573 | regs->ARM_r0 = -EINTR; | |
574 | break; | |
575 | } | |
576 | /* fallthrough */ | |
577 | case -ERESTARTNOINTR: | |
578 | restart_syscall(regs); | |
579 | } | |
580 | } | |
581 | ||
582 | /* | |
583 | * translate the signal | |
584 | */ | |
585 | if (usig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap) | |
586 | usig = thread->exec_domain->signal_invmap[usig]; | |
587 | ||
588 | /* | |
589 | * Set up the stack frame | |
590 | */ | |
591 | if (ka->sa.sa_flags & SA_SIGINFO) | |
592 | ret = setup_rt_frame(usig, ka, info, oldset, regs); | |
593 | else | |
594 | ret = setup_frame(usig, ka, oldset, regs); | |
595 | ||
596 | /* | |
597 | * Check that the resulting registers are actually sane. | |
598 | */ | |
599 | ret |= !valid_user_regs(regs); | |
600 | ||
69be8f18 | 601 | if (ret != 0) { |
a6c61e9d DJ |
602 | force_sigsegv(sig, tsk); |
603 | return; | |
1da177e4 LT |
604 | } |
605 | ||
a6c61e9d DJ |
606 | /* |
607 | * Block the signal if we were successful. | |
608 | */ | |
609 | spin_lock_irq(&tsk->sighand->siglock); | |
610 | sigorsets(&tsk->blocked, &tsk->blocked, | |
611 | &ka->sa.sa_mask); | |
612 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
613 | sigaddset(&tsk->blocked, sig); | |
614 | recalc_sigpending(); | |
615 | spin_unlock_irq(&tsk->sighand->siglock); | |
1da177e4 | 616 | |
1da177e4 LT |
617 | } |
618 | ||
619 | /* | |
620 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
621 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
622 | * mistake. | |
623 | * | |
624 | * Note that we go through the signals twice: once to check the signals that | |
625 | * the kernel can handle, and then we build all the user-level signal handling | |
626 | * stack-frames in one go after that. | |
627 | */ | |
628 | static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall) | |
629 | { | |
630 | struct k_sigaction ka; | |
631 | siginfo_t info; | |
632 | int signr; | |
633 | ||
634 | /* | |
635 | * We want the common case to go fast, which | |
636 | * is why we may in certain cases get here from | |
637 | * kernel mode. Just return without doing anything | |
638 | * if so. | |
639 | */ | |
640 | if (!user_mode(regs)) | |
641 | return 0; | |
642 | ||
bdb94f3a | 643 | if (try_to_freeze()) |
1da177e4 LT |
644 | goto no_signal; |
645 | ||
646 | if (current->ptrace & PT_SINGLESTEP) | |
647 | ptrace_cancel_bpt(current); | |
648 | ||
649 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
650 | if (signr > 0) { | |
651 | handle_signal(signr, &ka, &info, oldset, regs, syscall); | |
652 | if (current->ptrace & PT_SINGLESTEP) | |
653 | ptrace_set_bpt(current); | |
654 | return 1; | |
655 | } | |
656 | ||
657 | no_signal: | |
658 | /* | |
659 | * No signal to deliver to the process - restart the syscall. | |
660 | */ | |
661 | if (syscall) { | |
662 | if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) { | |
663 | if (thumb_mode(regs)) { | |
f606a6ff | 664 | regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE; |
1da177e4 LT |
665 | regs->ARM_pc -= 2; |
666 | } else { | |
f606a6ff NP |
667 | #if defined(CONFIG_AEABI) && !defined(CONFIG_OABI_COMPAT) |
668 | regs->ARM_r7 = __NR_restart_syscall; | |
669 | regs->ARM_pc -= 4; | |
670 | #else | |
1da177e4 | 671 | u32 __user *usp; |
f606a6ff | 672 | u32 swival = __NR_restart_syscall; |
1da177e4 LT |
673 | |
674 | regs->ARM_sp -= 12; | |
675 | usp = (u32 __user *)regs->ARM_sp; | |
676 | ||
f606a6ff NP |
677 | /* |
678 | * Either we supports OABI only, or we have | |
679 | * EABI with the OABI compat layer enabled. | |
680 | * In the later case we don't know if user | |
681 | * space is EABI or not, and if not we must | |
682 | * not clobber r7. Always using the OABI | |
683 | * syscall solves that issue and works for | |
684 | * all those cases. | |
685 | */ | |
95eaa5fa | 686 | swival = swival - __NR_SYSCALL_BASE + __NR_OABI_SYSCALL_BASE; |
f606a6ff | 687 | |
1da177e4 LT |
688 | put_user(regs->ARM_pc, &usp[0]); |
689 | /* swi __NR_restart_syscall */ | |
f606a6ff | 690 | put_user(0xef000000 | swival, &usp[1]); |
1da177e4 LT |
691 | /* ldr pc, [sp], #12 */ |
692 | put_user(0xe49df00c, &usp[2]); | |
693 | ||
694 | flush_icache_range((unsigned long)usp, | |
695 | (unsigned long)(usp + 3)); | |
696 | ||
697 | regs->ARM_pc = regs->ARM_sp + 4; | |
f606a6ff | 698 | #endif |
1da177e4 LT |
699 | } |
700 | } | |
701 | if (regs->ARM_r0 == -ERESTARTNOHAND || | |
702 | regs->ARM_r0 == -ERESTARTSYS || | |
703 | regs->ARM_r0 == -ERESTARTNOINTR) { | |
704 | restart_syscall(regs); | |
705 | } | |
706 | } | |
707 | if (current->ptrace & PT_SINGLESTEP) | |
708 | ptrace_set_bpt(current); | |
709 | return 0; | |
710 | } | |
711 | ||
712 | asmlinkage void | |
713 | do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall) | |
714 | { | |
715 | if (thread_flags & _TIF_SIGPENDING) | |
716 | do_signal(¤t->blocked, regs, syscall); | |
717 | } |