2 * linux/arch/arm/kernel/signal.c
4 * Copyright (C) 1995-2002 Russell King
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.
10 #include <linux/config.h>
11 #include <linux/errno.h>
12 #include <linux/signal.h>
13 #include <linux/ptrace.h>
14 #include <linux/personality.h>
16 #include <asm/cacheflush.h>
17 #include <asm/ucontext.h>
18 #include <asm/uaccess.h>
19 #include <asm/unistd.h>
24 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
27 * For ARM syscalls, we encode the syscall number into the instruction.
29 #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn))
30 #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn))
33 * With EABI, the syscall number has to be loaded into r7.
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))
39 * For Thumb syscalls, we pass the syscall number via r7. We therefore
40 * need two 16-bit instructions.
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))
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
,
50 static int do_signal(sigset_t
*oldset
, struct pt_regs
* regs
, int syscall
);
53 * atomically swap in the new signal mask, and wait for a signal.
55 asmlinkage
int sys_sigsuspend(int restart
, unsigned long oldmask
, old_sigset_t mask
, struct pt_regs
*regs
)
60 spin_lock_irq(¤t
->sighand
->siglock
);
61 saveset
= current
->blocked
;
62 siginitset(¤t
->blocked
, mask
);
64 spin_unlock_irq(¤t
->sighand
->siglock
);
65 regs
->ARM_r0
= -EINTR
;
68 current
->state
= TASK_INTERRUPTIBLE
;
70 if (do_signal(&saveset
, regs
, 0))
76 sys_rt_sigsuspend(sigset_t __user
*unewset
, size_t sigsetsize
, struct pt_regs
*regs
)
78 sigset_t saveset
, newset
;
80 /* XXX: Don't preclude handling different sized sigset_t's. */
81 if (sigsetsize
!= sizeof(sigset_t
))
84 if (copy_from_user(&newset
, unewset
, sizeof(newset
)))
86 sigdelsetmask(&newset
, ~_BLOCKABLE
);
88 spin_lock_irq(¤t
->sighand
->siglock
);
89 saveset
= current
->blocked
;
90 current
->blocked
= newset
;
92 spin_unlock_irq(¤t
->sighand
->siglock
);
93 regs
->ARM_r0
= -EINTR
;
96 current
->state
= TASK_INTERRUPTIBLE
;
98 if (do_signal(&saveset
, regs
, 0))
104 sys_sigaction(int sig
, const struct old_sigaction __user
*act
,
105 struct old_sigaction __user
*oact
)
107 struct k_sigaction new_ka
, old_ka
;
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
))
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
);
121 ret
= do_sigaction(sig
, act
? &new_ka
: NULL
, oact
? &old_ka
: NULL
);
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
))
128 __put_user(old_ka
.sa
.sa_flags
, &oact
->sa_flags
);
129 __put_user(old_ka
.sa
.sa_mask
.sig
[0], &oact
->sa_mask
);
137 /* iwmmxt_area is 0x98 bytes long, preceeded by 8 bytes of signature */
138 #define IWMMXT_STORAGE_SIZE (0x98 + 8)
139 #define IWMMXT_MAGIC0 0x12ef842a
140 #define IWMMXT_MAGIC1 0x1c07ca71
142 struct iwmmxt_sigframe
{
143 unsigned long magic0
;
144 unsigned long magic1
;
145 unsigned long storage
[0x98/4];
148 static int preserve_iwmmxt_context(struct iwmmxt_sigframe
*frame
)
150 char kbuf
[sizeof(*frame
) + 8];
151 struct iwmmxt_sigframe
*kframe
;
153 /* the iWMMXt context must be 64 bit aligned */
154 kframe
= (struct iwmmxt_sigframe
*)((unsigned long)(kbuf
+ 8) & ~7);
155 kframe
->magic0
= IWMMXT_MAGIC0
;
156 kframe
->magic1
= IWMMXT_MAGIC1
;
157 iwmmxt_task_copy(current_thread_info(), &kframe
->storage
);
158 return __copy_to_user(frame
, kframe
, sizeof(*frame
));
161 static int restore_iwmmxt_context(struct iwmmxt_sigframe
*frame
)
163 char kbuf
[sizeof(*frame
) + 8];
164 struct iwmmxt_sigframe
*kframe
;
166 /* the iWMMXt context must be 64 bit aligned */
167 kframe
= (struct iwmmxt_sigframe
*)((unsigned long)(kbuf
+ 8) & ~7);
168 if (__copy_from_user(kframe
, frame
, sizeof(*frame
)))
170 if (kframe
->magic0
!= IWMMXT_MAGIC0
||
171 kframe
->magic1
!= IWMMXT_MAGIC1
)
173 iwmmxt_task_restore(current_thread_info(), &kframe
->storage
);
180 * Auxiliary signal frame. This saves stuff like FP state.
181 * The layout of this structure is not part of the user ABI.
183 struct aux_sigframe
{
185 struct iwmmxt_sigframe iwmmxt
;
193 * Do a signal return; undo the signal stack. These are aligned to 64-bit.
196 struct sigcontext sc
;
198 unsigned long retcode
[2];
199 struct aux_sigframe aux
__attribute__((aligned(8)));
205 unsigned long retcode
[2];
206 struct aux_sigframe aux
__attribute__((aligned(8)));
210 restore_sigcontext(struct pt_regs
*regs
, struct sigcontext __user
*sc
,
211 struct aux_sigframe __user
*aux
)
215 __get_user_error(regs
->ARM_r0
, &sc
->arm_r0
, err
);
216 __get_user_error(regs
->ARM_r1
, &sc
->arm_r1
, err
);
217 __get_user_error(regs
->ARM_r2
, &sc
->arm_r2
, err
);
218 __get_user_error(regs
->ARM_r3
, &sc
->arm_r3
, err
);
219 __get_user_error(regs
->ARM_r4
, &sc
->arm_r4
, err
);
220 __get_user_error(regs
->ARM_r5
, &sc
->arm_r5
, err
);
221 __get_user_error(regs
->ARM_r6
, &sc
->arm_r6
, err
);
222 __get_user_error(regs
->ARM_r7
, &sc
->arm_r7
, err
);
223 __get_user_error(regs
->ARM_r8
, &sc
->arm_r8
, err
);
224 __get_user_error(regs
->ARM_r9
, &sc
->arm_r9
, err
);
225 __get_user_error(regs
->ARM_r10
, &sc
->arm_r10
, err
);
226 __get_user_error(regs
->ARM_fp
, &sc
->arm_fp
, err
);
227 __get_user_error(regs
->ARM_ip
, &sc
->arm_ip
, err
);
228 __get_user_error(regs
->ARM_sp
, &sc
->arm_sp
, err
);
229 __get_user_error(regs
->ARM_lr
, &sc
->arm_lr
, err
);
230 __get_user_error(regs
->ARM_pc
, &sc
->arm_pc
, err
);
231 __get_user_error(regs
->ARM_cpsr
, &sc
->arm_cpsr
, err
);
233 err
|= !valid_user_regs(regs
);
236 if (err
== 0 && test_thread_flag(TIF_USING_IWMMXT
))
237 err
|= restore_iwmmxt_context(&aux
->iwmmxt
);
241 // err |= vfp_restore_state(&aux->vfp);
247 asmlinkage
int sys_sigreturn(struct pt_regs
*regs
)
249 struct sigframe __user
*frame
;
252 /* Always make any pending restarted system calls return -EINTR */
253 current_thread_info()->restart_block
.fn
= do_no_restart_syscall
;
256 * Since we stacked the signal on a 64-bit boundary,
257 * then 'sp' should be word aligned here. If it's
258 * not, then the user is trying to mess with us.
260 if (regs
->ARM_sp
& 7)
263 frame
= (struct sigframe __user
*)regs
->ARM_sp
;
265 if (!access_ok(VERIFY_READ
, frame
, sizeof (*frame
)))
267 if (__copy_from_user(&set
, &frame
->sigmask
, sizeof(set
)))
270 sigdelsetmask(&set
, ~_BLOCKABLE
);
271 spin_lock_irq(¤t
->sighand
->siglock
);
272 current
->blocked
= set
;
274 spin_unlock_irq(¤t
->sighand
->siglock
);
276 if (restore_sigcontext(regs
, &frame
->sc
, &frame
->aux
))
279 /* Send SIGTRAP if we're single-stepping */
280 if (current
->ptrace
& PT_SINGLESTEP
) {
281 ptrace_cancel_bpt(current
);
282 send_sig(SIGTRAP
, current
, 1);
288 force_sig(SIGSEGV
, current
);
292 asmlinkage
int sys_rt_sigreturn(struct pt_regs
*regs
)
294 struct rt_sigframe __user
*frame
;
297 /* Always make any pending restarted system calls return -EINTR */
298 current_thread_info()->restart_block
.fn
= do_no_restart_syscall
;
301 * Since we stacked the signal on a 64-bit boundary,
302 * then 'sp' should be word aligned here. If it's
303 * not, then the user is trying to mess with us.
305 if (regs
->ARM_sp
& 7)
308 frame
= (struct rt_sigframe __user
*)regs
->ARM_sp
;
310 if (!access_ok(VERIFY_READ
, frame
, sizeof (*frame
)))
312 if (__copy_from_user(&set
, &frame
->uc
.uc_sigmask
, sizeof(set
)))
315 sigdelsetmask(&set
, ~_BLOCKABLE
);
316 spin_lock_irq(¤t
->sighand
->siglock
);
317 current
->blocked
= set
;
319 spin_unlock_irq(¤t
->sighand
->siglock
);
321 if (restore_sigcontext(regs
, &frame
->uc
.uc_mcontext
, &frame
->aux
))
324 if (do_sigaltstack(&frame
->uc
.uc_stack
, NULL
, regs
->ARM_sp
) == -EFAULT
)
327 /* Send SIGTRAP if we're single-stepping */
328 if (current
->ptrace
& PT_SINGLESTEP
) {
329 ptrace_cancel_bpt(current
);
330 send_sig(SIGTRAP
, current
, 1);
336 force_sig(SIGSEGV
, current
);
341 setup_sigcontext(struct sigcontext __user
*sc
, struct aux_sigframe __user
*aux
,
342 struct pt_regs
*regs
, unsigned long mask
)
346 __put_user_error(regs
->ARM_r0
, &sc
->arm_r0
, err
);
347 __put_user_error(regs
->ARM_r1
, &sc
->arm_r1
, err
);
348 __put_user_error(regs
->ARM_r2
, &sc
->arm_r2
, err
);
349 __put_user_error(regs
->ARM_r3
, &sc
->arm_r3
, err
);
350 __put_user_error(regs
->ARM_r4
, &sc
->arm_r4
, err
);
351 __put_user_error(regs
->ARM_r5
, &sc
->arm_r5
, err
);
352 __put_user_error(regs
->ARM_r6
, &sc
->arm_r6
, err
);
353 __put_user_error(regs
->ARM_r7
, &sc
->arm_r7
, err
);
354 __put_user_error(regs
->ARM_r8
, &sc
->arm_r8
, err
);
355 __put_user_error(regs
->ARM_r9
, &sc
->arm_r9
, err
);
356 __put_user_error(regs
->ARM_r10
, &sc
->arm_r10
, err
);
357 __put_user_error(regs
->ARM_fp
, &sc
->arm_fp
, err
);
358 __put_user_error(regs
->ARM_ip
, &sc
->arm_ip
, err
);
359 __put_user_error(regs
->ARM_sp
, &sc
->arm_sp
, err
);
360 __put_user_error(regs
->ARM_lr
, &sc
->arm_lr
, err
);
361 __put_user_error(regs
->ARM_pc
, &sc
->arm_pc
, err
);
362 __put_user_error(regs
->ARM_cpsr
, &sc
->arm_cpsr
, err
);
364 __put_user_error(current
->thread
.trap_no
, &sc
->trap_no
, err
);
365 __put_user_error(current
->thread
.error_code
, &sc
->error_code
, err
);
366 __put_user_error(current
->thread
.address
, &sc
->fault_address
, err
);
367 __put_user_error(mask
, &sc
->oldmask
, err
);
370 if (err
== 0 && test_thread_flag(TIF_USING_IWMMXT
))
371 err
|= preserve_iwmmxt_context(&aux
->iwmmxt
);
375 // err |= vfp_save_state(&aux->vfp);
381 static inline void __user
*
382 get_sigframe(struct k_sigaction
*ka
, struct pt_regs
*regs
, int framesize
)
384 unsigned long sp
= regs
->ARM_sp
;
388 * This is the X/Open sanctioned signal stack switching.
390 if ((ka
->sa
.sa_flags
& SA_ONSTACK
) && !sas_ss_flags(sp
))
391 sp
= current
->sas_ss_sp
+ current
->sas_ss_size
;
394 * ATPCS B01 mandates 8-byte alignment
396 frame
= (void __user
*)((sp
- framesize
) & ~7);
399 * Check that we can actually write to the signal frame.
401 if (!access_ok(VERIFY_WRITE
, frame
, framesize
))
408 setup_return(struct pt_regs
*regs
, struct k_sigaction
*ka
,
409 unsigned long __user
*rc
, void __user
*frame
, int usig
)
411 unsigned long handler
= (unsigned long)ka
->sa
.sa_handler
;
412 unsigned long retcode
;
414 unsigned long cpsr
= regs
->ARM_cpsr
& ~PSR_f
;
417 * Maybe we need to deliver a 32-bit signal to a 26-bit task.
419 if (ka
->sa
.sa_flags
& SA_THIRTYTWO
)
420 cpsr
= (cpsr
& ~MODE_MASK
) | USR_MODE
;
422 #ifdef CONFIG_ARM_THUMB
423 if (elf_hwcap
& HWCAP_THUMB
) {
425 * The LSB of the handler determines if we're going to
426 * be using THUMB or ARM mode for this signal handler.
437 if (ka
->sa
.sa_flags
& SA_RESTORER
) {
438 retcode
= (unsigned long)ka
->sa
.sa_restorer
;
440 unsigned int idx
= thumb
<< 1;
442 if (ka
->sa
.sa_flags
& SA_SIGINFO
)
445 if (__put_user(sigreturn_codes
[idx
], rc
) ||
446 __put_user(sigreturn_codes
[idx
+1], rc
+1))
449 if (cpsr
& MODE32_BIT
) {
451 * 32-bit code can use the new high-page
452 * signal return code support.
454 retcode
= KERN_SIGRETURN_CODE
+ (idx
<< 2) + thumb
;
457 * Ensure that the instruction cache sees
458 * the return code written onto the stack.
460 flush_icache_range((unsigned long)rc
,
461 (unsigned long)(rc
+ 2));
463 retcode
= ((unsigned long)rc
) + thumb
;
468 regs
->ARM_sp
= (unsigned long)frame
;
469 regs
->ARM_lr
= retcode
;
470 regs
->ARM_pc
= handler
;
471 regs
->ARM_cpsr
= cpsr
;
477 setup_frame(int usig
, struct k_sigaction
*ka
, sigset_t
*set
, struct pt_regs
*regs
)
479 struct sigframe __user
*frame
= get_sigframe(ka
, regs
, sizeof(*frame
));
485 err
|= setup_sigcontext(&frame
->sc
, &frame
->aux
, regs
, set
->sig
[0]);
486 err
|= __copy_to_user(&frame
->sigmask
, set
, sizeof(*set
));
489 err
= setup_return(regs
, ka
, frame
->retcode
, frame
, usig
);
495 setup_rt_frame(int usig
, struct k_sigaction
*ka
, siginfo_t
*info
,
496 sigset_t
*set
, struct pt_regs
*regs
)
498 struct rt_sigframe __user
*frame
= get_sigframe(ka
, regs
, sizeof(*frame
));
505 err
|= copy_siginfo_to_user(&frame
->info
, info
);
507 __put_user_error(0, &frame
->uc
.uc_flags
, err
);
508 __put_user_error(NULL
, &frame
->uc
.uc_link
, err
);
510 memset(&stack
, 0, sizeof(stack
));
511 stack
.ss_sp
= (void __user
*)current
->sas_ss_sp
;
512 stack
.ss_flags
= sas_ss_flags(regs
->ARM_sp
);
513 stack
.ss_size
= current
->sas_ss_size
;
514 err
|= __copy_to_user(&frame
->uc
.uc_stack
, &stack
, sizeof(stack
));
516 err
|= setup_sigcontext(&frame
->uc
.uc_mcontext
, &frame
->aux
,
518 err
|= __copy_to_user(&frame
->uc
.uc_sigmask
, set
, sizeof(*set
));
521 err
= setup_return(regs
, ka
, frame
->retcode
, frame
, usig
);
525 * For realtime signals we must also set the second and third
526 * arguments for the signal handler.
527 * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06
529 regs
->ARM_r1
= (unsigned long)&frame
->info
;
530 regs
->ARM_r2
= (unsigned long)&frame
->uc
;
536 static inline void restart_syscall(struct pt_regs
*regs
)
538 regs
->ARM_r0
= regs
->ARM_ORIG_r0
;
539 regs
->ARM_pc
-= thumb_mode(regs
) ? 2 : 4;
543 * OK, we're invoking a handler
546 handle_signal(unsigned long sig
, struct k_sigaction
*ka
,
547 siginfo_t
*info
, sigset_t
*oldset
,
548 struct pt_regs
* regs
, int syscall
)
550 struct thread_info
*thread
= current_thread_info();
551 struct task_struct
*tsk
= current
;
556 * If we were from a system call, check for system call restarting...
559 switch (regs
->ARM_r0
) {
560 case -ERESTART_RESTARTBLOCK
:
561 case -ERESTARTNOHAND
:
562 regs
->ARM_r0
= -EINTR
;
565 if (!(ka
->sa
.sa_flags
& SA_RESTART
)) {
566 regs
->ARM_r0
= -EINTR
;
570 case -ERESTARTNOINTR
:
571 restart_syscall(regs
);
576 * translate the signal
578 if (usig
< 32 && thread
->exec_domain
&& thread
->exec_domain
->signal_invmap
)
579 usig
= thread
->exec_domain
->signal_invmap
[usig
];
582 * Set up the stack frame
584 if (ka
->sa
.sa_flags
& SA_SIGINFO
)
585 ret
= setup_rt_frame(usig
, ka
, info
, oldset
, regs
);
587 ret
= setup_frame(usig
, ka
, oldset
, regs
);
590 * Check that the resulting registers are actually sane.
592 ret
|= !valid_user_regs(regs
);
595 force_sigsegv(sig
, tsk
);
600 * Block the signal if we were successful.
602 spin_lock_irq(&tsk
->sighand
->siglock
);
603 sigorsets(&tsk
->blocked
, &tsk
->blocked
,
605 if (!(ka
->sa
.sa_flags
& SA_NODEFER
))
606 sigaddset(&tsk
->blocked
, sig
);
608 spin_unlock_irq(&tsk
->sighand
->siglock
);
613 * Note that 'init' is a special process: it doesn't get signals it doesn't
614 * want to handle. Thus you cannot kill init even with a SIGKILL even by
617 * Note that we go through the signals twice: once to check the signals that
618 * the kernel can handle, and then we build all the user-level signal handling
619 * stack-frames in one go after that.
621 static int do_signal(sigset_t
*oldset
, struct pt_regs
*regs
, int syscall
)
623 struct k_sigaction ka
;
628 * We want the common case to go fast, which
629 * is why we may in certain cases get here from
630 * kernel mode. Just return without doing anything
633 if (!user_mode(regs
))
639 if (current
->ptrace
& PT_SINGLESTEP
)
640 ptrace_cancel_bpt(current
);
642 signr
= get_signal_to_deliver(&info
, &ka
, regs
, NULL
);
644 handle_signal(signr
, &ka
, &info
, oldset
, regs
, syscall
);
645 if (current
->ptrace
& PT_SINGLESTEP
)
646 ptrace_set_bpt(current
);
652 * No signal to deliver to the process - restart the syscall.
655 if (regs
->ARM_r0
== -ERESTART_RESTARTBLOCK
) {
656 if (thumb_mode(regs
)) {
657 regs
->ARM_r7
= __NR_restart_syscall
;
663 usp
= (u32 __user
*)regs
->ARM_sp
;
665 put_user(regs
->ARM_pc
, &usp
[0]);
666 /* swi __NR_restart_syscall */
667 put_user(0xef000000 | __NR_restart_syscall
, &usp
[1]);
668 /* ldr pc, [sp], #12 */
669 put_user(0xe49df00c, &usp
[2]);
671 flush_icache_range((unsigned long)usp
,
672 (unsigned long)(usp
+ 3));
674 regs
->ARM_pc
= regs
->ARM_sp
+ 4;
677 if (regs
->ARM_r0
== -ERESTARTNOHAND
||
678 regs
->ARM_r0
== -ERESTARTSYS
||
679 regs
->ARM_r0
== -ERESTARTNOINTR
) {
680 restart_syscall(regs
);
683 if (current
->ptrace
& PT_SINGLESTEP
)
684 ptrace_set_bpt(current
);
689 do_notify_resume(struct pt_regs
*regs
, unsigned int thread_flags
, int syscall
)
691 if (thread_flags
& _TIF_SIGPENDING
)
692 do_signal(¤t
->blocked
, regs
, syscall
);
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