2 * linux/arch/arm/kernel/signal.c
4 * Copyright (C) 1995-2009 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/errno.h>
11 #include <linux/signal.h>
12 #include <linux/personality.h>
13 #include <linux/freezer.h>
14 #include <linux/uaccess.h>
15 #include <linux/tracehook.h>
18 #include <asm/cacheflush.h>
19 #include <asm/ucontext.h>
20 #include <asm/unistd.h>
26 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
29 * For ARM syscalls, we encode the syscall number into the instruction.
31 #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE))
32 #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE))
33 #define SWI_SYS_RESTART (0xef000000|__NR_restart_syscall|__NR_OABI_SYSCALL_BASE)
36 * With EABI, the syscall number has to be loaded into r7.
38 #define MOV_R7_NR_SIGRETURN (0xe3a07000 | (__NR_sigreturn - __NR_SYSCALL_BASE))
39 #define MOV_R7_NR_RT_SIGRETURN (0xe3a07000 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE))
42 * For Thumb syscalls, we pass the syscall number via r7. We therefore
43 * need two 16-bit instructions.
45 #define SWI_THUMB_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_sigreturn - __NR_SYSCALL_BASE))
46 #define SWI_THUMB_RT_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE))
48 const unsigned long sigreturn_codes
[7] = {
49 MOV_R7_NR_SIGRETURN
, SWI_SYS_SIGRETURN
, SWI_THUMB_SIGRETURN
,
50 MOV_R7_NR_RT_SIGRETURN
, SWI_SYS_RT_SIGRETURN
, SWI_THUMB_RT_SIGRETURN
,
54 * Either we support OABI only, or we have EABI with the OABI
55 * compat layer enabled. In the later case we don't know if
56 * user space is EABI or not, and if not we must not clobber r7.
57 * Always using the OABI syscall solves that issue and works for
60 const unsigned long syscall_restart_code
[2] = {
61 SWI_SYS_RESTART
, /* swi __NR_restart_syscall */
62 0xe49df004, /* ldr pc, [sp], #4 */
66 * atomically swap in the new signal mask, and wait for a signal.
68 asmlinkage
int sys_sigsuspend(int restart
, unsigned long oldmask
, old_sigset_t mask
)
71 spin_lock_irq(¤t
->sighand
->siglock
);
72 current
->saved_sigmask
= current
->blocked
;
73 siginitset(¤t
->blocked
, mask
);
75 spin_unlock_irq(¤t
->sighand
->siglock
);
77 current
->state
= TASK_INTERRUPTIBLE
;
79 set_restore_sigmask();
80 return -ERESTARTNOHAND
;
84 sys_sigaction(int sig
, const struct old_sigaction __user
*act
,
85 struct old_sigaction __user
*oact
)
87 struct k_sigaction new_ka
, old_ka
;
92 if (!access_ok(VERIFY_READ
, act
, sizeof(*act
)) ||
93 __get_user(new_ka
.sa
.sa_handler
, &act
->sa_handler
) ||
94 __get_user(new_ka
.sa
.sa_restorer
, &act
->sa_restorer
))
96 __get_user(new_ka
.sa
.sa_flags
, &act
->sa_flags
);
97 __get_user(mask
, &act
->sa_mask
);
98 siginitset(&new_ka
.sa
.sa_mask
, mask
);
101 ret
= do_sigaction(sig
, act
? &new_ka
: NULL
, oact
? &old_ka
: NULL
);
104 if (!access_ok(VERIFY_WRITE
, oact
, sizeof(*oact
)) ||
105 __put_user(old_ka
.sa
.sa_handler
, &oact
->sa_handler
) ||
106 __put_user(old_ka
.sa
.sa_restorer
, &oact
->sa_restorer
))
108 __put_user(old_ka
.sa
.sa_flags
, &oact
->sa_flags
);
109 __put_user(old_ka
.sa
.sa_mask
.sig
[0], &oact
->sa_mask
);
116 static int preserve_crunch_context(struct crunch_sigframe __user
*frame
)
118 char kbuf
[sizeof(*frame
) + 8];
119 struct crunch_sigframe
*kframe
;
121 /* the crunch context must be 64 bit aligned */
122 kframe
= (struct crunch_sigframe
*)((unsigned long)(kbuf
+ 8) & ~7);
123 kframe
->magic
= CRUNCH_MAGIC
;
124 kframe
->size
= CRUNCH_STORAGE_SIZE
;
125 crunch_task_copy(current_thread_info(), &kframe
->storage
);
126 return __copy_to_user(frame
, kframe
, sizeof(*frame
));
129 static int restore_crunch_context(struct crunch_sigframe __user
*frame
)
131 char kbuf
[sizeof(*frame
) + 8];
132 struct crunch_sigframe
*kframe
;
134 /* the crunch context must be 64 bit aligned */
135 kframe
= (struct crunch_sigframe
*)((unsigned long)(kbuf
+ 8) & ~7);
136 if (__copy_from_user(kframe
, frame
, sizeof(*frame
)))
138 if (kframe
->magic
!= CRUNCH_MAGIC
||
139 kframe
->size
!= CRUNCH_STORAGE_SIZE
)
141 crunch_task_restore(current_thread_info(), &kframe
->storage
);
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
->magic
= IWMMXT_MAGIC
;
156 kframe
->size
= IWMMXT_STORAGE_SIZE
;
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
->magic
!= IWMMXT_MAGIC
||
171 kframe
->size
!= IWMMXT_STORAGE_SIZE
)
173 iwmmxt_task_restore(current_thread_info(), &kframe
->storage
);
181 static int preserve_vfp_context(struct vfp_sigframe __user
*frame
)
183 struct thread_info
*thread
= current_thread_info();
184 struct vfp_hard_struct
*h
= &thread
->vfpstate
.hard
;
185 const unsigned long magic
= VFP_MAGIC
;
186 const unsigned long size
= VFP_STORAGE_SIZE
;
189 vfp_sync_hwstate(thread
);
190 __put_user_error(magic
, &frame
->magic
, err
);
191 __put_user_error(size
, &frame
->size
, err
);
194 * Copy the floating point registers. There can be unused
195 * registers see asm/hwcap.h for details.
197 err
|= __copy_to_user(&frame
->ufp
.fpregs
, &h
->fpregs
,
200 * Copy the status and control register.
202 __put_user_error(h
->fpscr
, &frame
->ufp
.fpscr
, err
);
205 * Copy the exception registers.
207 __put_user_error(h
->fpexc
, &frame
->ufp_exc
.fpexc
, err
);
208 __put_user_error(h
->fpinst
, &frame
->ufp_exc
.fpinst
, err
);
209 __put_user_error(h
->fpinst2
, &frame
->ufp_exc
.fpinst2
, err
);
211 return err
? -EFAULT
: 0;
214 static int restore_vfp_context(struct vfp_sigframe __user
*frame
)
216 struct thread_info
*thread
= current_thread_info();
217 struct vfp_hard_struct
*h
= &thread
->vfpstate
.hard
;
223 __get_user_error(magic
, &frame
->magic
, err
);
224 __get_user_error(size
, &frame
->size
, err
);
228 if (magic
!= VFP_MAGIC
|| size
!= VFP_STORAGE_SIZE
)
232 * Copy the floating point registers. There can be unused
233 * registers see asm/hwcap.h for details.
235 err
|= __copy_from_user(&h
->fpregs
, &frame
->ufp
.fpregs
,
238 * Copy the status and control register.
240 __get_user_error(h
->fpscr
, &frame
->ufp
.fpscr
, err
);
243 * Sanitise and restore the exception registers.
245 __get_user_error(fpexc
, &frame
->ufp_exc
.fpexc
, err
);
246 /* Ensure the VFP is enabled. */
248 /* Ensure FPINST2 is invalid and the exception flag is cleared. */
249 fpexc
&= ~(FPEXC_EX
| FPEXC_FP2V
);
252 __get_user_error(h
->fpinst
, &frame
->ufp_exc
.fpinst
, err
);
253 __get_user_error(h
->fpinst2
, &frame
->ufp_exc
.fpinst2
, err
);
256 vfp_flush_hwstate(thread
);
258 return err
? -EFAULT
: 0;
264 * Do a signal return; undo the signal stack. These are aligned to 64-bit.
268 unsigned long retcode
[2];
276 static int restore_sigframe(struct pt_regs
*regs
, struct sigframe __user
*sf
)
278 struct aux_sigframe __user
*aux
;
282 err
= __copy_from_user(&set
, &sf
->uc
.uc_sigmask
, sizeof(set
));
284 sigdelsetmask(&set
, ~_BLOCKABLE
);
285 spin_lock_irq(¤t
->sighand
->siglock
);
286 current
->blocked
= set
;
288 spin_unlock_irq(¤t
->sighand
->siglock
);
291 __get_user_error(regs
->ARM_r0
, &sf
->uc
.uc_mcontext
.arm_r0
, err
);
292 __get_user_error(regs
->ARM_r1
, &sf
->uc
.uc_mcontext
.arm_r1
, err
);
293 __get_user_error(regs
->ARM_r2
, &sf
->uc
.uc_mcontext
.arm_r2
, err
);
294 __get_user_error(regs
->ARM_r3
, &sf
->uc
.uc_mcontext
.arm_r3
, err
);
295 __get_user_error(regs
->ARM_r4
, &sf
->uc
.uc_mcontext
.arm_r4
, err
);
296 __get_user_error(regs
->ARM_r5
, &sf
->uc
.uc_mcontext
.arm_r5
, err
);
297 __get_user_error(regs
->ARM_r6
, &sf
->uc
.uc_mcontext
.arm_r6
, err
);
298 __get_user_error(regs
->ARM_r7
, &sf
->uc
.uc_mcontext
.arm_r7
, err
);
299 __get_user_error(regs
->ARM_r8
, &sf
->uc
.uc_mcontext
.arm_r8
, err
);
300 __get_user_error(regs
->ARM_r9
, &sf
->uc
.uc_mcontext
.arm_r9
, err
);
301 __get_user_error(regs
->ARM_r10
, &sf
->uc
.uc_mcontext
.arm_r10
, err
);
302 __get_user_error(regs
->ARM_fp
, &sf
->uc
.uc_mcontext
.arm_fp
, err
);
303 __get_user_error(regs
->ARM_ip
, &sf
->uc
.uc_mcontext
.arm_ip
, err
);
304 __get_user_error(regs
->ARM_sp
, &sf
->uc
.uc_mcontext
.arm_sp
, err
);
305 __get_user_error(regs
->ARM_lr
, &sf
->uc
.uc_mcontext
.arm_lr
, err
);
306 __get_user_error(regs
->ARM_pc
, &sf
->uc
.uc_mcontext
.arm_pc
, err
);
307 __get_user_error(regs
->ARM_cpsr
, &sf
->uc
.uc_mcontext
.arm_cpsr
, err
);
309 err
|= !valid_user_regs(regs
);
311 aux
= (struct aux_sigframe __user
*) sf
->uc
.uc_regspace
;
314 err
|= restore_crunch_context(&aux
->crunch
);
317 if (err
== 0 && test_thread_flag(TIF_USING_IWMMXT
))
318 err
|= restore_iwmmxt_context(&aux
->iwmmxt
);
322 err
|= restore_vfp_context(&aux
->vfp
);
328 asmlinkage
int sys_sigreturn(struct pt_regs
*regs
)
330 struct sigframe __user
*frame
;
332 /* Always make any pending restarted system calls return -EINTR */
333 current_thread_info()->restart_block
.fn
= do_no_restart_syscall
;
336 * Since we stacked the signal on a 64-bit boundary,
337 * then 'sp' should be word aligned here. If it's
338 * not, then the user is trying to mess with us.
340 if (regs
->ARM_sp
& 7)
343 frame
= (struct sigframe __user
*)regs
->ARM_sp
;
345 if (!access_ok(VERIFY_READ
, frame
, sizeof (*frame
)))
348 if (restore_sigframe(regs
, frame
))
351 single_step_trap(current
);
356 force_sig(SIGSEGV
, current
);
360 asmlinkage
int sys_rt_sigreturn(struct pt_regs
*regs
)
362 struct rt_sigframe __user
*frame
;
364 /* Always make any pending restarted system calls return -EINTR */
365 current_thread_info()->restart_block
.fn
= do_no_restart_syscall
;
368 * Since we stacked the signal on a 64-bit boundary,
369 * then 'sp' should be word aligned here. If it's
370 * not, then the user is trying to mess with us.
372 if (regs
->ARM_sp
& 7)
375 frame
= (struct rt_sigframe __user
*)regs
->ARM_sp
;
377 if (!access_ok(VERIFY_READ
, frame
, sizeof (*frame
)))
380 if (restore_sigframe(regs
, &frame
->sig
))
383 if (do_sigaltstack(&frame
->sig
.uc
.uc_stack
, NULL
, regs
->ARM_sp
) == -EFAULT
)
386 single_step_trap(current
);
391 force_sig(SIGSEGV
, current
);
396 setup_sigframe(struct sigframe __user
*sf
, struct pt_regs
*regs
, sigset_t
*set
)
398 struct aux_sigframe __user
*aux
;
401 __put_user_error(regs
->ARM_r0
, &sf
->uc
.uc_mcontext
.arm_r0
, err
);
402 __put_user_error(regs
->ARM_r1
, &sf
->uc
.uc_mcontext
.arm_r1
, err
);
403 __put_user_error(regs
->ARM_r2
, &sf
->uc
.uc_mcontext
.arm_r2
, err
);
404 __put_user_error(regs
->ARM_r3
, &sf
->uc
.uc_mcontext
.arm_r3
, err
);
405 __put_user_error(regs
->ARM_r4
, &sf
->uc
.uc_mcontext
.arm_r4
, err
);
406 __put_user_error(regs
->ARM_r5
, &sf
->uc
.uc_mcontext
.arm_r5
, err
);
407 __put_user_error(regs
->ARM_r6
, &sf
->uc
.uc_mcontext
.arm_r6
, err
);
408 __put_user_error(regs
->ARM_r7
, &sf
->uc
.uc_mcontext
.arm_r7
, err
);
409 __put_user_error(regs
->ARM_r8
, &sf
->uc
.uc_mcontext
.arm_r8
, err
);
410 __put_user_error(regs
->ARM_r9
, &sf
->uc
.uc_mcontext
.arm_r9
, err
);
411 __put_user_error(regs
->ARM_r10
, &sf
->uc
.uc_mcontext
.arm_r10
, err
);
412 __put_user_error(regs
->ARM_fp
, &sf
->uc
.uc_mcontext
.arm_fp
, err
);
413 __put_user_error(regs
->ARM_ip
, &sf
->uc
.uc_mcontext
.arm_ip
, err
);
414 __put_user_error(regs
->ARM_sp
, &sf
->uc
.uc_mcontext
.arm_sp
, err
);
415 __put_user_error(regs
->ARM_lr
, &sf
->uc
.uc_mcontext
.arm_lr
, err
);
416 __put_user_error(regs
->ARM_pc
, &sf
->uc
.uc_mcontext
.arm_pc
, err
);
417 __put_user_error(regs
->ARM_cpsr
, &sf
->uc
.uc_mcontext
.arm_cpsr
, err
);
419 __put_user_error(current
->thread
.trap_no
, &sf
->uc
.uc_mcontext
.trap_no
, err
);
420 __put_user_error(current
->thread
.error_code
, &sf
->uc
.uc_mcontext
.error_code
, err
);
421 __put_user_error(current
->thread
.address
, &sf
->uc
.uc_mcontext
.fault_address
, err
);
422 __put_user_error(set
->sig
[0], &sf
->uc
.uc_mcontext
.oldmask
, err
);
424 err
|= __copy_to_user(&sf
->uc
.uc_sigmask
, set
, sizeof(*set
));
426 aux
= (struct aux_sigframe __user
*) sf
->uc
.uc_regspace
;
429 err
|= preserve_crunch_context(&aux
->crunch
);
432 if (err
== 0 && test_thread_flag(TIF_USING_IWMMXT
))
433 err
|= preserve_iwmmxt_context(&aux
->iwmmxt
);
437 err
|= preserve_vfp_context(&aux
->vfp
);
439 __put_user_error(0, &aux
->end_magic
, err
);
444 static inline void __user
*
445 get_sigframe(struct k_sigaction
*ka
, struct pt_regs
*regs
, int framesize
)
447 unsigned long sp
= regs
->ARM_sp
;
451 * This is the X/Open sanctioned signal stack switching.
453 if ((ka
->sa
.sa_flags
& SA_ONSTACK
) && !sas_ss_flags(sp
))
454 sp
= current
->sas_ss_sp
+ current
->sas_ss_size
;
457 * ATPCS B01 mandates 8-byte alignment
459 frame
= (void __user
*)((sp
- framesize
) & ~7);
462 * Check that we can actually write to the signal frame.
464 if (!access_ok(VERIFY_WRITE
, frame
, framesize
))
471 setup_return(struct pt_regs
*regs
, struct k_sigaction
*ka
,
472 unsigned long __user
*rc
, void __user
*frame
, int usig
)
474 unsigned long handler
= (unsigned long)ka
->sa
.sa_handler
;
475 unsigned long retcode
;
477 unsigned long cpsr
= regs
->ARM_cpsr
& ~(PSR_f
| PSR_E_BIT
);
479 cpsr
|= PSR_ENDSTATE
;
482 * Maybe we need to deliver a 32-bit signal to a 26-bit task.
484 if (ka
->sa
.sa_flags
& SA_THIRTYTWO
)
485 cpsr
= (cpsr
& ~MODE_MASK
) | USR_MODE
;
487 #ifdef CONFIG_ARM_THUMB
488 if (elf_hwcap
& HWCAP_THUMB
) {
490 * The LSB of the handler determines if we're going to
491 * be using THUMB or ARM mode for this signal handler.
497 #if __LINUX_ARM_ARCH__ >= 7
498 /* clear the If-Then Thumb-2 execution state */
499 cpsr
&= ~PSR_IT_MASK
;
506 if (ka
->sa
.sa_flags
& SA_RESTORER
) {
507 retcode
= (unsigned long)ka
->sa
.sa_restorer
;
509 unsigned int idx
= thumb
<< 1;
511 if (ka
->sa
.sa_flags
& SA_SIGINFO
)
514 if (__put_user(sigreturn_codes
[idx
], rc
) ||
515 __put_user(sigreturn_codes
[idx
+1], rc
+1))
518 if (cpsr
& MODE32_BIT
) {
520 * 32-bit code can use the new high-page
521 * signal return code support.
523 retcode
= KERN_SIGRETURN_CODE
+ (idx
<< 2) + thumb
;
526 * Ensure that the instruction cache sees
527 * the return code written onto the stack.
529 flush_icache_range((unsigned long)rc
,
530 (unsigned long)(rc
+ 2));
532 retcode
= ((unsigned long)rc
) + thumb
;
537 regs
->ARM_sp
= (unsigned long)frame
;
538 regs
->ARM_lr
= retcode
;
539 regs
->ARM_pc
= handler
;
540 regs
->ARM_cpsr
= cpsr
;
546 setup_frame(int usig
, struct k_sigaction
*ka
, sigset_t
*set
, struct pt_regs
*regs
)
548 struct sigframe __user
*frame
= get_sigframe(ka
, regs
, sizeof(*frame
));
555 * Set uc.uc_flags to a value which sc.trap_no would never have.
557 __put_user_error(0x5ac3c35a, &frame
->uc
.uc_flags
, err
);
559 err
|= setup_sigframe(frame
, regs
, set
);
561 err
= setup_return(regs
, ka
, frame
->retcode
, frame
, usig
);
567 setup_rt_frame(int usig
, struct k_sigaction
*ka
, siginfo_t
*info
,
568 sigset_t
*set
, struct pt_regs
*regs
)
570 struct rt_sigframe __user
*frame
= get_sigframe(ka
, regs
, sizeof(*frame
));
577 err
|= copy_siginfo_to_user(&frame
->info
, info
);
579 __put_user_error(0, &frame
->sig
.uc
.uc_flags
, err
);
580 __put_user_error(NULL
, &frame
->sig
.uc
.uc_link
, err
);
582 memset(&stack
, 0, sizeof(stack
));
583 stack
.ss_sp
= (void __user
*)current
->sas_ss_sp
;
584 stack
.ss_flags
= sas_ss_flags(regs
->ARM_sp
);
585 stack
.ss_size
= current
->sas_ss_size
;
586 err
|= __copy_to_user(&frame
->sig
.uc
.uc_stack
, &stack
, sizeof(stack
));
588 err
|= setup_sigframe(&frame
->sig
, regs
, set
);
590 err
= setup_return(regs
, ka
, frame
->sig
.retcode
, frame
, usig
);
594 * For realtime signals we must also set the second and third
595 * arguments for the signal handler.
596 * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06
598 regs
->ARM_r1
= (unsigned long)&frame
->info
;
599 regs
->ARM_r2
= (unsigned long)&frame
->sig
.uc
;
605 static inline void setup_syscall_restart(struct pt_regs
*regs
)
607 regs
->ARM_r0
= regs
->ARM_ORIG_r0
;
608 regs
->ARM_pc
-= thumb_mode(regs
) ? 2 : 4;
612 * OK, we're invoking a handler
615 handle_signal(unsigned long sig
, struct k_sigaction
*ka
,
616 siginfo_t
*info
, sigset_t
*oldset
,
617 struct pt_regs
* regs
, int syscall
)
619 struct thread_info
*thread
= current_thread_info();
620 struct task_struct
*tsk
= current
;
625 * If we were from a system call, check for system call restarting...
628 switch (regs
->ARM_r0
) {
629 case -ERESTART_RESTARTBLOCK
:
630 case -ERESTARTNOHAND
:
631 regs
->ARM_r0
= -EINTR
;
634 if (!(ka
->sa
.sa_flags
& SA_RESTART
)) {
635 regs
->ARM_r0
= -EINTR
;
639 case -ERESTARTNOINTR
:
640 setup_syscall_restart(regs
);
645 * translate the signal
647 if (usig
< 32 && thread
->exec_domain
&& thread
->exec_domain
->signal_invmap
)
648 usig
= thread
->exec_domain
->signal_invmap
[usig
];
651 * Set up the stack frame
653 if (ka
->sa
.sa_flags
& SA_SIGINFO
)
654 ret
= setup_rt_frame(usig
, ka
, info
, oldset
, regs
);
656 ret
= setup_frame(usig
, ka
, oldset
, regs
);
659 * Check that the resulting registers are actually sane.
661 ret
|= !valid_user_regs(regs
);
664 force_sigsegv(sig
, tsk
);
669 * Block the signal if we were successful.
671 spin_lock_irq(&tsk
->sighand
->siglock
);
672 sigorsets(&tsk
->blocked
, &tsk
->blocked
,
674 if (!(ka
->sa
.sa_flags
& SA_NODEFER
))
675 sigaddset(&tsk
->blocked
, sig
);
677 spin_unlock_irq(&tsk
->sighand
->siglock
);
683 * Note that 'init' is a special process: it doesn't get signals it doesn't
684 * want to handle. Thus you cannot kill init even with a SIGKILL even by
687 * Note that we go through the signals twice: once to check the signals that
688 * the kernel can handle, and then we build all the user-level signal handling
689 * stack-frames in one go after that.
691 static void do_signal(struct pt_regs
*regs
, int syscall
)
693 struct k_sigaction ka
;
698 * We want the common case to go fast, which
699 * is why we may in certain cases get here from
700 * kernel mode. Just return without doing anything
703 if (!user_mode(regs
))
709 single_step_clear(current
);
711 signr
= get_signal_to_deliver(&info
, &ka
, regs
, NULL
);
715 if (test_thread_flag(TIF_RESTORE_SIGMASK
))
716 oldset
= ¤t
->saved_sigmask
;
718 oldset
= ¤t
->blocked
;
719 if (handle_signal(signr
, &ka
, &info
, oldset
, regs
, syscall
) == 0) {
721 * A signal was successfully delivered; the saved
722 * sigmask will have been stored in the signal frame,
723 * and will be restored by sigreturn, so we can simply
724 * clear the TIF_RESTORE_SIGMASK flag.
726 if (test_thread_flag(TIF_RESTORE_SIGMASK
))
727 clear_thread_flag(TIF_RESTORE_SIGMASK
);
729 single_step_set(current
);
735 * No signal to deliver to the process - restart the syscall.
738 if (regs
->ARM_r0
== -ERESTART_RESTARTBLOCK
) {
739 if (thumb_mode(regs
)) {
740 regs
->ARM_r7
= __NR_restart_syscall
- __NR_SYSCALL_BASE
;
743 #if defined(CONFIG_AEABI) && !defined(CONFIG_OABI_COMPAT)
744 regs
->ARM_r7
= __NR_restart_syscall
;
750 usp
= (u32 __user
*)regs
->ARM_sp
;
752 if (put_user(regs
->ARM_pc
, usp
) == 0) {
753 regs
->ARM_pc
= KERN_RESTART_CODE
;
756 force_sigsegv(0, current
);
761 if (regs
->ARM_r0
== -ERESTARTNOHAND
||
762 regs
->ARM_r0
== -ERESTARTSYS
||
763 regs
->ARM_r0
== -ERESTARTNOINTR
) {
764 setup_syscall_restart(regs
);
767 /* If there's no signal to deliver, we just put the saved sigmask
770 if (test_thread_flag(TIF_RESTORE_SIGMASK
)) {
771 clear_thread_flag(TIF_RESTORE_SIGMASK
);
772 sigprocmask(SIG_SETMASK
, ¤t
->saved_sigmask
, NULL
);
775 single_step_set(current
);
779 do_notify_resume(struct pt_regs
*regs
, unsigned int thread_flags
, int syscall
)
781 if (thread_flags
& _TIF_SIGPENDING
)
782 do_signal(regs
, syscall
);
784 if (thread_flags
& _TIF_NOTIFY_RESUME
) {
785 clear_thread_flag(TIF_NOTIFY_RESUME
);
786 tracehook_notify_resume(regs
);
787 if (current
->replacement_session_keyring
)
788 key_replace_session_keyring();