Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/arch/arm/kernel/signal.c | |
3 | * | |
ab72b007 | 4 | * Copyright (C) 1995-2009 Russell King |
1da177e4 LT |
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> | |
1da177e4 | 12 | #include <linux/personality.h> |
7dfb7103 | 13 | #include <linux/freezer.h> |
33fa9b13 | 14 | #include <linux/uaccess.h> |
733e5e4b | 15 | #include <linux/tracehook.h> |
1da177e4 | 16 | |
ee90dabc | 17 | #include <asm/elf.h> |
1da177e4 LT |
18 | #include <asm/cacheflush.h> |
19 | #include <asm/ucontext.h> | |
1da177e4 LT |
20 | #include <asm/unistd.h> |
21 | ||
22 | #include "ptrace.h" | |
e00d349e | 23 | #include "signal.h" |
1da177e4 LT |
24 | |
25 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
26 | ||
27 | /* | |
28 | * For ARM syscalls, we encode the syscall number into the instruction. | |
29 | */ | |
ee4cd588 | 30 | #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE)) |
31 | #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE)) | |
ab72b007 | 32 | #define SWI_SYS_RESTART (0xef000000|__NR_restart_syscall|__NR_OABI_SYSCALL_BASE) |
1da177e4 | 33 | |
fcca538b NP |
34 | /* |
35 | * With EABI, the syscall number has to be loaded into r7. | |
36 | */ | |
37 | #define MOV_R7_NR_SIGRETURN (0xe3a07000 | (__NR_sigreturn - __NR_SYSCALL_BASE)) | |
38 | #define MOV_R7_NR_RT_SIGRETURN (0xe3a07000 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) | |
39 | ||
1da177e4 LT |
40 | /* |
41 | * For Thumb syscalls, we pass the syscall number via r7. We therefore | |
42 | * need two 16-bit instructions. | |
43 | */ | |
44 | #define SWI_THUMB_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_sigreturn - __NR_SYSCALL_BASE)) | |
45 | #define SWI_THUMB_RT_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) | |
46 | ||
fcca538b NP |
47 | const unsigned long sigreturn_codes[7] = { |
48 | MOV_R7_NR_SIGRETURN, SWI_SYS_SIGRETURN, SWI_THUMB_SIGRETURN, | |
49 | MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN, | |
1da177e4 LT |
50 | }; |
51 | ||
ab72b007 RK |
52 | /* |
53 | * Either we support OABI only, or we have EABI with the OABI | |
54 | * compat layer enabled. In the later case we don't know if | |
55 | * user space is EABI or not, and if not we must not clobber r7. | |
56 | * Always using the OABI syscall solves that issue and works for | |
57 | * all those cases. | |
58 | */ | |
59 | const unsigned long syscall_restart_code[2] = { | |
60 | SWI_SYS_RESTART, /* swi __NR_restart_syscall */ | |
61 | 0xe49df004, /* ldr pc, [sp], #4 */ | |
62 | }; | |
63 | ||
1da177e4 LT |
64 | /* |
65 | * atomically swap in the new signal mask, and wait for a signal. | |
66 | */ | |
36984265 | 67 | asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask) |
1da177e4 | 68 | { |
1da177e4 LT |
69 | mask &= _BLOCKABLE; |
70 | spin_lock_irq(¤t->sighand->siglock); | |
36984265 | 71 | current->saved_sigmask = current->blocked; |
1da177e4 LT |
72 | siginitset(¤t->blocked, mask); |
73 | recalc_sigpending(); | |
74 | spin_unlock_irq(¤t->sighand->siglock); | |
1da177e4 | 75 | |
36984265 MP |
76 | current->state = TASK_INTERRUPTIBLE; |
77 | schedule(); | |
78 | set_restore_sigmask(); | |
79 | return -ERESTARTNOHAND; | |
1da177e4 LT |
80 | } |
81 | ||
82 | asmlinkage int | |
83 | sys_sigaction(int sig, const struct old_sigaction __user *act, | |
84 | struct old_sigaction __user *oact) | |
85 | { | |
86 | struct k_sigaction new_ka, old_ka; | |
87 | int ret; | |
88 | ||
89 | if (act) { | |
90 | old_sigset_t mask; | |
91 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | |
92 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
93 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | |
94 | return -EFAULT; | |
95 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); | |
96 | __get_user(mask, &act->sa_mask); | |
97 | siginitset(&new_ka.sa.sa_mask, mask); | |
98 | } | |
99 | ||
100 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
101 | ||
102 | if (!ret && oact) { | |
103 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
104 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
105 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | |
106 | return -EFAULT; | |
107 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); | |
108 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
109 | } | |
110 | ||
111 | return ret; | |
112 | } | |
113 | ||
3bec6ded | 114 | #ifdef CONFIG_CRUNCH |
65a5053b | 115 | static int preserve_crunch_context(struct crunch_sigframe __user *frame) |
3bec6ded LB |
116 | { |
117 | char kbuf[sizeof(*frame) + 8]; | |
118 | struct crunch_sigframe *kframe; | |
119 | ||
120 | /* the crunch context must be 64 bit aligned */ | |
121 | kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
122 | kframe->magic = CRUNCH_MAGIC; | |
123 | kframe->size = CRUNCH_STORAGE_SIZE; | |
124 | crunch_task_copy(current_thread_info(), &kframe->storage); | |
125 | return __copy_to_user(frame, kframe, sizeof(*frame)); | |
126 | } | |
127 | ||
65a5053b | 128 | static int restore_crunch_context(struct crunch_sigframe __user *frame) |
3bec6ded LB |
129 | { |
130 | char kbuf[sizeof(*frame) + 8]; | |
131 | struct crunch_sigframe *kframe; | |
132 | ||
133 | /* the crunch context must be 64 bit aligned */ | |
134 | kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
135 | if (__copy_from_user(kframe, frame, sizeof(*frame))) | |
136 | return -1; | |
137 | if (kframe->magic != CRUNCH_MAGIC || | |
138 | kframe->size != CRUNCH_STORAGE_SIZE) | |
139 | return -1; | |
140 | crunch_task_restore(current_thread_info(), &kframe->storage); | |
141 | return 0; | |
142 | } | |
143 | #endif | |
144 | ||
1da177e4 LT |
145 | #ifdef CONFIG_IWMMXT |
146 | ||
1da177e4 LT |
147 | static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame) |
148 | { | |
69b04754 HD |
149 | char kbuf[sizeof(*frame) + 8]; |
150 | struct iwmmxt_sigframe *kframe; | |
1da177e4 LT |
151 | |
152 | /* the iWMMXt context must be 64 bit aligned */ | |
69b04754 | 153 | kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); |
85fe0681 DJ |
154 | kframe->magic = IWMMXT_MAGIC; |
155 | kframe->size = IWMMXT_STORAGE_SIZE; | |
69b04754 HD |
156 | iwmmxt_task_copy(current_thread_info(), &kframe->storage); |
157 | return __copy_to_user(frame, kframe, sizeof(*frame)); | |
1da177e4 LT |
158 | } |
159 | ||
160 | static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame) | |
161 | { | |
69b04754 HD |
162 | char kbuf[sizeof(*frame) + 8]; |
163 | struct iwmmxt_sigframe *kframe; | |
164 | ||
165 | /* the iWMMXt context must be 64 bit aligned */ | |
166 | kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
167 | if (__copy_from_user(kframe, frame, sizeof(*frame))) | |
168 | return -1; | |
85fe0681 DJ |
169 | if (kframe->magic != IWMMXT_MAGIC || |
170 | kframe->size != IWMMXT_STORAGE_SIZE) | |
69b04754 HD |
171 | return -1; |
172 | iwmmxt_task_restore(current_thread_info(), &kframe->storage); | |
173 | return 0; | |
1da177e4 LT |
174 | } |
175 | ||
176 | #endif | |
177 | ||
1da177e4 LT |
178 | /* |
179 | * Do a signal return; undo the signal stack. These are aligned to 64-bit. | |
180 | */ | |
181 | struct sigframe { | |
7d4fdc19 | 182 | struct ucontext uc; |
fcca538b | 183 | unsigned long retcode[2]; |
1da177e4 LT |
184 | }; |
185 | ||
186 | struct rt_sigframe { | |
1da177e4 | 187 | struct siginfo info; |
cb3504e8 | 188 | struct sigframe sig; |
1da177e4 LT |
189 | }; |
190 | ||
68071484 | 191 | static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf) |
1da177e4 | 192 | { |
85fe0681 | 193 | struct aux_sigframe __user *aux; |
68071484 RK |
194 | sigset_t set; |
195 | int err; | |
196 | ||
197 | err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); | |
198 | if (err == 0) { | |
199 | sigdelsetmask(&set, ~_BLOCKABLE); | |
200 | spin_lock_irq(¤t->sighand->siglock); | |
201 | current->blocked = set; | |
202 | recalc_sigpending(); | |
203 | spin_unlock_irq(¤t->sighand->siglock); | |
204 | } | |
1da177e4 | 205 | |
68071484 RK |
206 | __get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); |
207 | __get_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); | |
208 | __get_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); | |
209 | __get_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); | |
210 | __get_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); | |
211 | __get_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); | |
212 | __get_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); | |
213 | __get_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); | |
214 | __get_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); | |
215 | __get_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); | |
216 | __get_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); | |
217 | __get_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); | |
218 | __get_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); | |
219 | __get_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); | |
220 | __get_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); | |
221 | __get_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); | |
222 | __get_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); | |
1da177e4 LT |
223 | |
224 | err |= !valid_user_regs(regs); | |
225 | ||
85fe0681 | 226 | aux = (struct aux_sigframe __user *) sf->uc.uc_regspace; |
3bec6ded LB |
227 | #ifdef CONFIG_CRUNCH |
228 | if (err == 0) | |
229 | err |= restore_crunch_context(&aux->crunch); | |
230 | #endif | |
1da177e4 LT |
231 | #ifdef CONFIG_IWMMXT |
232 | if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) | |
233 | err |= restore_iwmmxt_context(&aux->iwmmxt); | |
234 | #endif | |
235 | #ifdef CONFIG_VFP | |
236 | // if (err == 0) | |
68071484 | 237 | // err |= vfp_restore_state(&sf->aux.vfp); |
1da177e4 LT |
238 | #endif |
239 | ||
240 | return err; | |
241 | } | |
242 | ||
243 | asmlinkage int sys_sigreturn(struct pt_regs *regs) | |
244 | { | |
245 | struct sigframe __user *frame; | |
1da177e4 LT |
246 | |
247 | /* Always make any pending restarted system calls return -EINTR */ | |
248 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
249 | ||
250 | /* | |
251 | * Since we stacked the signal on a 64-bit boundary, | |
252 | * then 'sp' should be word aligned here. If it's | |
253 | * not, then the user is trying to mess with us. | |
254 | */ | |
255 | if (regs->ARM_sp & 7) | |
256 | goto badframe; | |
257 | ||
258 | frame = (struct sigframe __user *)regs->ARM_sp; | |
259 | ||
260 | if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) | |
261 | goto badframe; | |
1da177e4 | 262 | |
68071484 | 263 | if (restore_sigframe(regs, frame)) |
1da177e4 LT |
264 | goto badframe; |
265 | ||
b2a0d36f | 266 | single_step_trap(current); |
1da177e4 LT |
267 | |
268 | return regs->ARM_r0; | |
269 | ||
270 | badframe: | |
271 | force_sig(SIGSEGV, current); | |
272 | return 0; | |
273 | } | |
274 | ||
275 | asmlinkage int sys_rt_sigreturn(struct pt_regs *regs) | |
276 | { | |
277 | struct rt_sigframe __user *frame; | |
1da177e4 LT |
278 | |
279 | /* Always make any pending restarted system calls return -EINTR */ | |
280 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
281 | ||
282 | /* | |
283 | * Since we stacked the signal on a 64-bit boundary, | |
284 | * then 'sp' should be word aligned here. If it's | |
285 | * not, then the user is trying to mess with us. | |
286 | */ | |
287 | if (regs->ARM_sp & 7) | |
288 | goto badframe; | |
289 | ||
290 | frame = (struct rt_sigframe __user *)regs->ARM_sp; | |
291 | ||
292 | if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) | |
293 | goto badframe; | |
1da177e4 | 294 | |
68071484 | 295 | if (restore_sigframe(regs, &frame->sig)) |
1da177e4 LT |
296 | goto badframe; |
297 | ||
cb3504e8 | 298 | if (do_sigaltstack(&frame->sig.uc.uc_stack, NULL, regs->ARM_sp) == -EFAULT) |
1da177e4 LT |
299 | goto badframe; |
300 | ||
b2a0d36f | 301 | single_step_trap(current); |
1da177e4 LT |
302 | |
303 | return regs->ARM_r0; | |
304 | ||
305 | badframe: | |
306 | force_sig(SIGSEGV, current); | |
307 | return 0; | |
308 | } | |
309 | ||
310 | static int | |
aca6ca10 | 311 | setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set) |
1da177e4 | 312 | { |
85fe0681 | 313 | struct aux_sigframe __user *aux; |
1da177e4 LT |
314 | int err = 0; |
315 | ||
aca6ca10 RK |
316 | __put_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); |
317 | __put_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); | |
318 | __put_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); | |
319 | __put_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); | |
320 | __put_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); | |
321 | __put_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); | |
322 | __put_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); | |
323 | __put_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); | |
324 | __put_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); | |
325 | __put_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); | |
326 | __put_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); | |
327 | __put_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); | |
328 | __put_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); | |
329 | __put_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); | |
330 | __put_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); | |
331 | __put_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); | |
332 | __put_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); | |
333 | ||
334 | __put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no, err); | |
335 | __put_user_error(current->thread.error_code, &sf->uc.uc_mcontext.error_code, err); | |
336 | __put_user_error(current->thread.address, &sf->uc.uc_mcontext.fault_address, err); | |
337 | __put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err); | |
338 | ||
339 | err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set)); | |
1da177e4 | 340 | |
85fe0681 | 341 | aux = (struct aux_sigframe __user *) sf->uc.uc_regspace; |
3bec6ded LB |
342 | #ifdef CONFIG_CRUNCH |
343 | if (err == 0) | |
344 | err |= preserve_crunch_context(&aux->crunch); | |
345 | #endif | |
1da177e4 LT |
346 | #ifdef CONFIG_IWMMXT |
347 | if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) | |
348 | err |= preserve_iwmmxt_context(&aux->iwmmxt); | |
349 | #endif | |
350 | #ifdef CONFIG_VFP | |
351 | // if (err == 0) | |
aca6ca10 | 352 | // err |= vfp_save_state(&sf->aux.vfp); |
1da177e4 | 353 | #endif |
85fe0681 | 354 | __put_user_error(0, &aux->end_magic, err); |
1da177e4 LT |
355 | |
356 | return err; | |
357 | } | |
358 | ||
359 | static inline void __user * | |
360 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, int framesize) | |
361 | { | |
362 | unsigned long sp = regs->ARM_sp; | |
363 | void __user *frame; | |
364 | ||
365 | /* | |
366 | * This is the X/Open sanctioned signal stack switching. | |
367 | */ | |
368 | if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp)) | |
369 | sp = current->sas_ss_sp + current->sas_ss_size; | |
370 | ||
371 | /* | |
372 | * ATPCS B01 mandates 8-byte alignment | |
373 | */ | |
374 | frame = (void __user *)((sp - framesize) & ~7); | |
375 | ||
376 | /* | |
377 | * Check that we can actually write to the signal frame. | |
378 | */ | |
379 | if (!access_ok(VERIFY_WRITE, frame, framesize)) | |
380 | frame = NULL; | |
381 | ||
382 | return frame; | |
383 | } | |
384 | ||
385 | static int | |
386 | setup_return(struct pt_regs *regs, struct k_sigaction *ka, | |
387 | unsigned long __user *rc, void __user *frame, int usig) | |
388 | { | |
389 | unsigned long handler = (unsigned long)ka->sa.sa_handler; | |
390 | unsigned long retcode; | |
391 | int thumb = 0; | |
392 | unsigned long cpsr = regs->ARM_cpsr & ~PSR_f; | |
393 | ||
394 | /* | |
395 | * Maybe we need to deliver a 32-bit signal to a 26-bit task. | |
396 | */ | |
397 | if (ka->sa.sa_flags & SA_THIRTYTWO) | |
398 | cpsr = (cpsr & ~MODE_MASK) | USR_MODE; | |
399 | ||
400 | #ifdef CONFIG_ARM_THUMB | |
401 | if (elf_hwcap & HWCAP_THUMB) { | |
402 | /* | |
403 | * The LSB of the handler determines if we're going to | |
404 | * be using THUMB or ARM mode for this signal handler. | |
405 | */ | |
406 | thumb = handler & 1; | |
407 | ||
d71e1352 | 408 | if (thumb) { |
1da177e4 | 409 | cpsr |= PSR_T_BIT; |
d71e1352 CM |
410 | #if __LINUX_ARM_ARCH__ >= 7 |
411 | /* clear the If-Then Thumb-2 execution state */ | |
412 | cpsr &= ~PSR_IT_MASK; | |
413 | #endif | |
414 | } else | |
1da177e4 LT |
415 | cpsr &= ~PSR_T_BIT; |
416 | } | |
417 | #endif | |
418 | ||
419 | if (ka->sa.sa_flags & SA_RESTORER) { | |
420 | retcode = (unsigned long)ka->sa.sa_restorer; | |
421 | } else { | |
fcca538b | 422 | unsigned int idx = thumb << 1; |
1da177e4 LT |
423 | |
424 | if (ka->sa.sa_flags & SA_SIGINFO) | |
fcca538b | 425 | idx += 3; |
1da177e4 | 426 | |
fcca538b NP |
427 | if (__put_user(sigreturn_codes[idx], rc) || |
428 | __put_user(sigreturn_codes[idx+1], rc+1)) | |
1da177e4 LT |
429 | return 1; |
430 | ||
e00d349e RK |
431 | if (cpsr & MODE32_BIT) { |
432 | /* | |
433 | * 32-bit code can use the new high-page | |
434 | * signal return code support. | |
435 | */ | |
436 | retcode = KERN_SIGRETURN_CODE + (idx << 2) + thumb; | |
437 | } else { | |
438 | /* | |
439 | * Ensure that the instruction cache sees | |
440 | * the return code written onto the stack. | |
441 | */ | |
442 | flush_icache_range((unsigned long)rc, | |
fcca538b | 443 | (unsigned long)(rc + 2)); |
e00d349e RK |
444 | |
445 | retcode = ((unsigned long)rc) + thumb; | |
446 | } | |
1da177e4 LT |
447 | } |
448 | ||
449 | regs->ARM_r0 = usig; | |
450 | regs->ARM_sp = (unsigned long)frame; | |
451 | regs->ARM_lr = retcode; | |
452 | regs->ARM_pc = handler; | |
453 | regs->ARM_cpsr = cpsr; | |
454 | ||
455 | return 0; | |
456 | } | |
457 | ||
458 | static int | |
459 | setup_frame(int usig, struct k_sigaction *ka, sigset_t *set, struct pt_regs *regs) | |
460 | { | |
461 | struct sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame)); | |
462 | int err = 0; | |
463 | ||
464 | if (!frame) | |
465 | return 1; | |
466 | ||
ca195cfe RK |
467 | /* |
468 | * Set uc.uc_flags to a value which sc.trap_no would never have. | |
469 | */ | |
470 | __put_user_error(0x5ac3c35a, &frame->uc.uc_flags, err); | |
1da177e4 | 471 | |
aca6ca10 | 472 | err |= setup_sigframe(frame, regs, set); |
1da177e4 | 473 | if (err == 0) |
fcca538b | 474 | err = setup_return(regs, ka, frame->retcode, frame, usig); |
1da177e4 LT |
475 | |
476 | return err; | |
477 | } | |
478 | ||
479 | static int | |
480 | setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info, | |
481 | sigset_t *set, struct pt_regs *regs) | |
482 | { | |
483 | struct rt_sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame)); | |
484 | stack_t stack; | |
485 | int err = 0; | |
486 | ||
487 | if (!frame) | |
488 | return 1; | |
489 | ||
1da177e4 LT |
490 | err |= copy_siginfo_to_user(&frame->info, info); |
491 | ||
cb3504e8 RK |
492 | __put_user_error(0, &frame->sig.uc.uc_flags, err); |
493 | __put_user_error(NULL, &frame->sig.uc.uc_link, err); | |
1da177e4 LT |
494 | |
495 | memset(&stack, 0, sizeof(stack)); | |
496 | stack.ss_sp = (void __user *)current->sas_ss_sp; | |
497 | stack.ss_flags = sas_ss_flags(regs->ARM_sp); | |
498 | stack.ss_size = current->sas_ss_size; | |
cb3504e8 | 499 | err |= __copy_to_user(&frame->sig.uc.uc_stack, &stack, sizeof(stack)); |
1da177e4 | 500 | |
aca6ca10 | 501 | err |= setup_sigframe(&frame->sig, regs, set); |
1da177e4 | 502 | if (err == 0) |
cb3504e8 | 503 | err = setup_return(regs, ka, frame->sig.retcode, frame, usig); |
1da177e4 LT |
504 | |
505 | if (err == 0) { | |
506 | /* | |
507 | * For realtime signals we must also set the second and third | |
508 | * arguments for the signal handler. | |
509 | * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06 | |
510 | */ | |
511 | regs->ARM_r1 = (unsigned long)&frame->info; | |
cb3504e8 | 512 | regs->ARM_r2 = (unsigned long)&frame->sig.uc; |
1da177e4 LT |
513 | } |
514 | ||
515 | return err; | |
516 | } | |
517 | ||
288ddad5 | 518 | static inline void setup_syscall_restart(struct pt_regs *regs) |
1da177e4 LT |
519 | { |
520 | regs->ARM_r0 = regs->ARM_ORIG_r0; | |
521 | regs->ARM_pc -= thumb_mode(regs) ? 2 : 4; | |
522 | } | |
523 | ||
524 | /* | |
525 | * OK, we're invoking a handler | |
526 | */ | |
36984265 | 527 | static int |
1da177e4 LT |
528 | handle_signal(unsigned long sig, struct k_sigaction *ka, |
529 | siginfo_t *info, sigset_t *oldset, | |
530 | struct pt_regs * regs, int syscall) | |
531 | { | |
532 | struct thread_info *thread = current_thread_info(); | |
533 | struct task_struct *tsk = current; | |
534 | int usig = sig; | |
535 | int ret; | |
536 | ||
537 | /* | |
538 | * If we were from a system call, check for system call restarting... | |
539 | */ | |
540 | if (syscall) { | |
541 | switch (regs->ARM_r0) { | |
542 | case -ERESTART_RESTARTBLOCK: | |
543 | case -ERESTARTNOHAND: | |
544 | regs->ARM_r0 = -EINTR; | |
545 | break; | |
546 | case -ERESTARTSYS: | |
547 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
548 | regs->ARM_r0 = -EINTR; | |
549 | break; | |
550 | } | |
551 | /* fallthrough */ | |
552 | case -ERESTARTNOINTR: | |
288ddad5 | 553 | setup_syscall_restart(regs); |
1da177e4 LT |
554 | } |
555 | } | |
556 | ||
557 | /* | |
558 | * translate the signal | |
559 | */ | |
560 | if (usig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap) | |
561 | usig = thread->exec_domain->signal_invmap[usig]; | |
562 | ||
563 | /* | |
564 | * Set up the stack frame | |
565 | */ | |
566 | if (ka->sa.sa_flags & SA_SIGINFO) | |
567 | ret = setup_rt_frame(usig, ka, info, oldset, regs); | |
568 | else | |
569 | ret = setup_frame(usig, ka, oldset, regs); | |
570 | ||
571 | /* | |
572 | * Check that the resulting registers are actually sane. | |
573 | */ | |
574 | ret |= !valid_user_regs(regs); | |
575 | ||
69be8f18 | 576 | if (ret != 0) { |
a6c61e9d | 577 | force_sigsegv(sig, tsk); |
36984265 | 578 | return ret; |
1da177e4 LT |
579 | } |
580 | ||
a6c61e9d DJ |
581 | /* |
582 | * Block the signal if we were successful. | |
583 | */ | |
584 | spin_lock_irq(&tsk->sighand->siglock); | |
585 | sigorsets(&tsk->blocked, &tsk->blocked, | |
586 | &ka->sa.sa_mask); | |
587 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
588 | sigaddset(&tsk->blocked, sig); | |
589 | recalc_sigpending(); | |
590 | spin_unlock_irq(&tsk->sighand->siglock); | |
1da177e4 | 591 | |
36984265 | 592 | return 0; |
1da177e4 LT |
593 | } |
594 | ||
595 | /* | |
596 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
597 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
598 | * mistake. | |
599 | * | |
600 | * Note that we go through the signals twice: once to check the signals that | |
601 | * the kernel can handle, and then we build all the user-level signal handling | |
602 | * stack-frames in one go after that. | |
603 | */ | |
36984265 | 604 | static void do_signal(struct pt_regs *regs, int syscall) |
1da177e4 LT |
605 | { |
606 | struct k_sigaction ka; | |
607 | siginfo_t info; | |
608 | int signr; | |
609 | ||
610 | /* | |
611 | * We want the common case to go fast, which | |
612 | * is why we may in certain cases get here from | |
613 | * kernel mode. Just return without doing anything | |
614 | * if so. | |
615 | */ | |
616 | if (!user_mode(regs)) | |
36984265 | 617 | return; |
1da177e4 | 618 | |
bdb94f3a | 619 | if (try_to_freeze()) |
1da177e4 LT |
620 | goto no_signal; |
621 | ||
b2a0d36f | 622 | single_step_clear(current); |
1da177e4 LT |
623 | |
624 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
625 | if (signr > 0) { | |
36984265 MP |
626 | sigset_t *oldset; |
627 | ||
628 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) | |
629 | oldset = ¤t->saved_sigmask; | |
630 | else | |
631 | oldset = ¤t->blocked; | |
632 | if (handle_signal(signr, &ka, &info, oldset, regs, syscall) == 0) { | |
633 | /* | |
634 | * A signal was successfully delivered; the saved | |
635 | * sigmask will have been stored in the signal frame, | |
636 | * and will be restored by sigreturn, so we can simply | |
637 | * clear the TIF_RESTORE_SIGMASK flag. | |
638 | */ | |
639 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) | |
640 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
641 | } | |
b2a0d36f | 642 | single_step_set(current); |
36984265 | 643 | return; |
1da177e4 LT |
644 | } |
645 | ||
646 | no_signal: | |
647 | /* | |
648 | * No signal to deliver to the process - restart the syscall. | |
649 | */ | |
650 | if (syscall) { | |
651 | if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) { | |
652 | if (thumb_mode(regs)) { | |
f606a6ff | 653 | regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE; |
1da177e4 LT |
654 | regs->ARM_pc -= 2; |
655 | } else { | |
f606a6ff NP |
656 | #if defined(CONFIG_AEABI) && !defined(CONFIG_OABI_COMPAT) |
657 | regs->ARM_r7 = __NR_restart_syscall; | |
658 | regs->ARM_pc -= 4; | |
659 | #else | |
1da177e4 LT |
660 | u32 __user *usp; |
661 | ||
ab72b007 | 662 | regs->ARM_sp -= 4; |
1da177e4 LT |
663 | usp = (u32 __user *)regs->ARM_sp; |
664 | ||
3336f4f0 JP |
665 | if (put_user(regs->ARM_pc, usp) == 0) { |
666 | regs->ARM_pc = KERN_RESTART_CODE; | |
667 | } else { | |
668 | regs->ARM_sp += 4; | |
669 | force_sigsegv(0, current); | |
670 | } | |
f606a6ff | 671 | #endif |
1da177e4 LT |
672 | } |
673 | } | |
674 | if (regs->ARM_r0 == -ERESTARTNOHAND || | |
675 | regs->ARM_r0 == -ERESTARTSYS || | |
676 | regs->ARM_r0 == -ERESTARTNOINTR) { | |
288ddad5 | 677 | setup_syscall_restart(regs); |
1da177e4 | 678 | } |
36984265 MP |
679 | |
680 | /* If there's no signal to deliver, we just put the saved sigmask | |
681 | * back. | |
682 | */ | |
683 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) { | |
684 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
685 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); | |
686 | } | |
1da177e4 | 687 | } |
b2a0d36f | 688 | single_step_set(current); |
1da177e4 LT |
689 | } |
690 | ||
691 | asmlinkage void | |
692 | do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall) | |
693 | { | |
694 | if (thread_flags & _TIF_SIGPENDING) | |
36984265 | 695 | do_signal(regs, syscall); |
d0420c83 DH |
696 | |
697 | if (thread_flags & _TIF_NOTIFY_RESUME) { | |
698 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
699 | tracehook_notify_resume(regs); | |
ee18d64c DH |
700 | if (current->replacement_session_keyring) |
701 | key_replace_session_keyring(); | |
d0420c83 | 702 | } |
1da177e4 | 703 | } |