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Linux/arch/arm/kernel/signal.c

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  1 // SPDX-License-Identifier: GPL-2.0-only
  2 /*
  3  *  linux/arch/arm/kernel/signal.c
  4  *
  5  *  Copyright (C) 1995-2009 Russell King
  6  */
  7 #include <linux/errno.h>
  8 #include <linux/random.h>
  9 #include <linux/signal.h>
 10 #include <linux/personality.h>
 11 #include <linux/uaccess.h>
 12 #include <linux/resume_user_mode.h>
 13 #include <linux/uprobes.h>
 14 #include <linux/syscalls.h>
 15 
 16 #include <asm/elf.h>
 17 #include <asm/cacheflush.h>
 18 #include <asm/traps.h>
 19 #include <asm/unistd.h>
 20 #include <asm/vfp.h>
 21 #include <asm/syscalls.h>
 22 
 23 #include "signal.h"
 24 
 25 extern const unsigned long sigreturn_codes[17];
 26 
 27 static unsigned long signal_return_offset;
 28 
 29 #ifdef CONFIG_IWMMXT
 30 
 31 static int preserve_iwmmxt_context(struct iwmmxt_sigframe __user *frame)
 32 {
 33         char kbuf[sizeof(*frame) + 8];
 34         struct iwmmxt_sigframe *kframe;
 35         int err = 0;
 36 
 37         /* the iWMMXt context must be 64 bit aligned */
 38         kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
 39 
 40         if (test_thread_flag(TIF_USING_IWMMXT)) {
 41                 kframe->magic = IWMMXT_MAGIC;
 42                 kframe->size = IWMMXT_STORAGE_SIZE;
 43                 iwmmxt_task_copy(current_thread_info(), &kframe->storage);
 44         } else {
 45                 /*
 46                  * For bug-compatibility with older kernels, some space
 47                  * has to be reserved for iWMMXt even if it's not used.
 48                  * Set the magic and size appropriately so that properly
 49                  * written userspace can skip it reliably:
 50                  */
 51                 *kframe = (struct iwmmxt_sigframe) {
 52                         .magic = DUMMY_MAGIC,
 53                         .size  = IWMMXT_STORAGE_SIZE,
 54                 };
 55         }
 56 
 57         err = __copy_to_user(frame, kframe, sizeof(*kframe));
 58 
 59         return err;
 60 }
 61 
 62 static int restore_iwmmxt_context(char __user **auxp)
 63 {
 64         struct iwmmxt_sigframe __user *frame =
 65                 (struct iwmmxt_sigframe __user *)*auxp;
 66         char kbuf[sizeof(*frame) + 8];
 67         struct iwmmxt_sigframe *kframe;
 68 
 69         /* the iWMMXt context must be 64 bit aligned */
 70         kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
 71         if (__copy_from_user(kframe, frame, sizeof(*frame)))
 72                 return -1;
 73 
 74         /*
 75          * For non-iWMMXt threads: a single iwmmxt_sigframe-sized dummy
 76          * block is discarded for compatibility with setup_sigframe() if
 77          * present, but we don't mandate its presence.  If some other
 78          * magic is here, it's not for us:
 79          */
 80         if (!test_thread_flag(TIF_USING_IWMMXT) &&
 81             kframe->magic != DUMMY_MAGIC)
 82                 return 0;
 83 
 84         if (kframe->size != IWMMXT_STORAGE_SIZE)
 85                 return -1;
 86 
 87         if (test_thread_flag(TIF_USING_IWMMXT)) {
 88                 if (kframe->magic != IWMMXT_MAGIC)
 89                         return -1;
 90 
 91                 iwmmxt_task_restore(current_thread_info(), &kframe->storage);
 92         }
 93 
 94         *auxp += IWMMXT_STORAGE_SIZE;
 95         return 0;
 96 }
 97 
 98 #endif
 99 
100 #ifdef CONFIG_VFP
101 
102 static int preserve_vfp_context(struct vfp_sigframe __user *frame)
103 {
104         struct vfp_sigframe kframe;
105         int err = 0;
106 
107         memset(&kframe, 0, sizeof(kframe));
108         kframe.magic = VFP_MAGIC;
109         kframe.size = VFP_STORAGE_SIZE;
110 
111         err = vfp_preserve_user_clear_hwstate(&kframe.ufp, &kframe.ufp_exc);
112         if (err)
113                 return err;
114 
115         return __copy_to_user(frame, &kframe, sizeof(kframe));
116 }
117 
118 static int restore_vfp_context(char __user **auxp)
119 {
120         struct vfp_sigframe frame;
121         int err;
122 
123         err = __copy_from_user(&frame, *auxp, sizeof(frame));
124         if (err)
125                 return err;
126 
127         if (frame.magic != VFP_MAGIC || frame.size != VFP_STORAGE_SIZE)
128                 return -EINVAL;
129 
130         *auxp += sizeof(frame);
131         return vfp_restore_user_hwstate(&frame.ufp, &frame.ufp_exc);
132 }
133 
134 #endif
135 
136 /*
137  * Do a signal return; undo the signal stack.  These are aligned to 64-bit.
138  */
139 
140 static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
141 {
142         struct sigcontext context;
143         char __user *aux;
144         sigset_t set;
145         int err;
146 
147         err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
148         if (err == 0)
149                 set_current_blocked(&set);
150 
151         err |= __copy_from_user(&context, &sf->uc.uc_mcontext, sizeof(context));
152         if (err == 0) {
153                 regs->ARM_r0 = context.arm_r0;
154                 regs->ARM_r1 = context.arm_r1;
155                 regs->ARM_r2 = context.arm_r2;
156                 regs->ARM_r3 = context.arm_r3;
157                 regs->ARM_r4 = context.arm_r4;
158                 regs->ARM_r5 = context.arm_r5;
159                 regs->ARM_r6 = context.arm_r6;
160                 regs->ARM_r7 = context.arm_r7;
161                 regs->ARM_r8 = context.arm_r8;
162                 regs->ARM_r9 = context.arm_r9;
163                 regs->ARM_r10 = context.arm_r10;
164                 regs->ARM_fp = context.arm_fp;
165                 regs->ARM_ip = context.arm_ip;
166                 regs->ARM_sp = context.arm_sp;
167                 regs->ARM_lr = context.arm_lr;
168                 regs->ARM_pc = context.arm_pc;
169                 regs->ARM_cpsr = context.arm_cpsr;
170         }
171 
172         err |= !valid_user_regs(regs);
173 
174         aux = (char __user *) sf->uc.uc_regspace;
175 #ifdef CONFIG_IWMMXT
176         if (err == 0)
177                 err |= restore_iwmmxt_context(&aux);
178 #endif
179 #ifdef CONFIG_VFP
180         if (err == 0)
181                 err |= restore_vfp_context(&aux);
182 #endif
183 
184         return err;
185 }
186 
187 asmlinkage int sys_sigreturn(struct pt_regs *regs)
188 {
189         struct sigframe __user *frame;
190 
191         /* Always make any pending restarted system calls return -EINTR */
192         current->restart_block.fn = do_no_restart_syscall;
193 
194         /*
195          * Since we stacked the signal on a 64-bit boundary,
196          * then 'sp' should be word aligned here.  If it's
197          * not, then the user is trying to mess with us.
198          */
199         if (regs->ARM_sp & 7)
200                 goto badframe;
201 
202         frame = (struct sigframe __user *)regs->ARM_sp;
203 
204         if (!access_ok(frame, sizeof (*frame)))
205                 goto badframe;
206 
207         if (restore_sigframe(regs, frame))
208                 goto badframe;
209 
210         return regs->ARM_r0;
211 
212 badframe:
213         force_sig(SIGSEGV);
214         return 0;
215 }
216 
217 asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
218 {
219         struct rt_sigframe __user *frame;
220 
221         /* Always make any pending restarted system calls return -EINTR */
222         current->restart_block.fn = do_no_restart_syscall;
223 
224         /*
225          * Since we stacked the signal on a 64-bit boundary,
226          * then 'sp' should be word aligned here.  If it's
227          * not, then the user is trying to mess with us.
228          */
229         if (regs->ARM_sp & 7)
230                 goto badframe;
231 
232         frame = (struct rt_sigframe __user *)regs->ARM_sp;
233 
234         if (!access_ok(frame, sizeof (*frame)))
235                 goto badframe;
236 
237         if (restore_sigframe(regs, &frame->sig))
238                 goto badframe;
239 
240         if (restore_altstack(&frame->sig.uc.uc_stack))
241                 goto badframe;
242 
243         return regs->ARM_r0;
244 
245 badframe:
246         force_sig(SIGSEGV);
247         return 0;
248 }
249 
250 static int
251 setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set)
252 {
253         struct aux_sigframe __user *aux;
254         struct sigcontext context;
255         int err = 0;
256 
257         context = (struct sigcontext) {
258                 .arm_r0        = regs->ARM_r0,
259                 .arm_r1        = regs->ARM_r1,
260                 .arm_r2        = regs->ARM_r2,
261                 .arm_r3        = regs->ARM_r3,
262                 .arm_r4        = regs->ARM_r4,
263                 .arm_r5        = regs->ARM_r5,
264                 .arm_r6        = regs->ARM_r6,
265                 .arm_r7        = regs->ARM_r7,
266                 .arm_r8        = regs->ARM_r8,
267                 .arm_r9        = regs->ARM_r9,
268                 .arm_r10       = regs->ARM_r10,
269                 .arm_fp        = regs->ARM_fp,
270                 .arm_ip        = regs->ARM_ip,
271                 .arm_sp        = regs->ARM_sp,
272                 .arm_lr        = regs->ARM_lr,
273                 .arm_pc        = regs->ARM_pc,
274                 .arm_cpsr      = regs->ARM_cpsr,
275 
276                 .trap_no       = current->thread.trap_no,
277                 .error_code    = current->thread.error_code,
278                 .fault_address = current->thread.address,
279                 .oldmask       = set->sig[0],
280         };
281 
282         err |= __copy_to_user(&sf->uc.uc_mcontext, &context, sizeof(context));
283 
284         err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
285 
286         aux = (struct aux_sigframe __user *) sf->uc.uc_regspace;
287 #ifdef CONFIG_IWMMXT
288         if (err == 0)
289                 err |= preserve_iwmmxt_context(&aux->iwmmxt);
290 #endif
291 #ifdef CONFIG_VFP
292         if (err == 0)
293                 err |= preserve_vfp_context(&aux->vfp);
294 #endif
295         err |= __put_user(0, &aux->end_magic);
296 
297         return err;
298 }
299 
300 static inline void __user *
301 get_sigframe(struct ksignal *ksig, struct pt_regs *regs, int framesize)
302 {
303         unsigned long sp = sigsp(regs->ARM_sp, ksig);
304         void __user *frame;
305 
306         /*
307          * ATPCS B01 mandates 8-byte alignment
308          */
309         frame = (void __user *)((sp - framesize) & ~7);
310 
311         /*
312          * Check that we can actually write to the signal frame.
313          */
314         if (!access_ok(frame, framesize))
315                 frame = NULL;
316 
317         return frame;
318 }
319 
320 static int
321 setup_return(struct pt_regs *regs, struct ksignal *ksig,
322              unsigned long __user *rc, void __user *frame)
323 {
324         unsigned long handler = (unsigned long)ksig->ka.sa.sa_handler;
325         unsigned long handler_fdpic_GOT = 0;
326         unsigned long retcode;
327         unsigned int idx, thumb = 0;
328         unsigned long cpsr = regs->ARM_cpsr & ~(PSR_f | PSR_E_BIT);
329         bool fdpic = IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&
330                      (current->personality & FDPIC_FUNCPTRS);
331 
332         if (fdpic) {
333                 unsigned long __user *fdpic_func_desc =
334                                         (unsigned long __user *)handler;
335                 if (__get_user(handler, &fdpic_func_desc[0]) ||
336                     __get_user(handler_fdpic_GOT, &fdpic_func_desc[1]))
337                         return 1;
338         }
339 
340         cpsr |= PSR_ENDSTATE;
341 
342         /*
343          * Maybe we need to deliver a 32-bit signal to a 26-bit task.
344          */
345         if (ksig->ka.sa.sa_flags & SA_THIRTYTWO)
346                 cpsr = (cpsr & ~MODE_MASK) | USR_MODE;
347 
348 #ifdef CONFIG_ARM_THUMB
349         if (elf_hwcap & HWCAP_THUMB) {
350                 /*
351                  * The LSB of the handler determines if we're going to
352                  * be using THUMB or ARM mode for this signal handler.
353                  */
354                 thumb = handler & 1;
355 
356                 /*
357                  * Clear the If-Then Thumb-2 execution state.  ARM spec
358                  * requires this to be all 000s in ARM mode.  Snapdragon
359                  * S4/Krait misbehaves on a Thumb=>ARM signal transition
360                  * without this.
361                  *
362                  * We must do this whenever we are running on a Thumb-2
363                  * capable CPU, which includes ARMv6T2.  However, we elect
364                  * to always do this to simplify the code; this field is
365                  * marked UNK/SBZP for older architectures.
366                  */
367                 cpsr &= ~PSR_IT_MASK;
368 
369                 if (thumb) {
370                         cpsr |= PSR_T_BIT;
371                 } else
372                         cpsr &= ~PSR_T_BIT;
373         }
374 #endif
375 
376         if (ksig->ka.sa.sa_flags & SA_RESTORER) {
377                 retcode = (unsigned long)ksig->ka.sa.sa_restorer;
378                 if (fdpic) {
379                         /*
380                          * We need code to load the function descriptor.
381                          * That code follows the standard sigreturn code
382                          * (6 words), and is made of 3 + 2 words for each
383                          * variant. The 4th copied word is the actual FD
384                          * address that the assembly code expects.
385                          */
386                         idx = 6 + thumb * 3;
387                         if (ksig->ka.sa.sa_flags & SA_SIGINFO)
388                                 idx += 5;
389                         if (__put_user(sigreturn_codes[idx],   rc  ) ||
390                             __put_user(sigreturn_codes[idx+1], rc+1) ||
391                             __put_user(sigreturn_codes[idx+2], rc+2) ||
392                             __put_user(retcode,                rc+3))
393                                 return 1;
394                         goto rc_finish;
395                 }
396         } else {
397                 idx = thumb << 1;
398                 if (ksig->ka.sa.sa_flags & SA_SIGINFO)
399                         idx += 3;
400 
401                 /*
402                  * Put the sigreturn code on the stack no matter which return
403                  * mechanism we use in order to remain ABI compliant
404                  */
405                 if (__put_user(sigreturn_codes[idx],   rc) ||
406                     __put_user(sigreturn_codes[idx+1], rc+1))
407                         return 1;
408 
409 rc_finish:
410 #ifdef CONFIG_MMU
411                 if (cpsr & MODE32_BIT) {
412                         struct mm_struct *mm = current->mm;
413 
414                         /*
415                          * 32-bit code can use the signal return page
416                          * except when the MPU has protected the vectors
417                          * page from PL0
418                          */
419                         retcode = mm->context.sigpage + signal_return_offset +
420                                   (idx << 2) + thumb;
421                 } else
422 #endif
423                 {
424                         /*
425                          * Ensure that the instruction cache sees
426                          * the return code written onto the stack.
427                          */
428                         flush_icache_range((unsigned long)rc,
429                                            (unsigned long)(rc + 3));
430 
431                         retcode = ((unsigned long)rc) + thumb;
432                 }
433         }
434 
435         regs->ARM_r0 = ksig->sig;
436         regs->ARM_sp = (unsigned long)frame;
437         regs->ARM_lr = retcode;
438         regs->ARM_pc = handler;
439         if (fdpic)
440                 regs->ARM_r9 = handler_fdpic_GOT;
441         regs->ARM_cpsr = cpsr;
442 
443         return 0;
444 }
445 
446 static int
447 setup_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs)
448 {
449         struct sigframe __user *frame = get_sigframe(ksig, regs, sizeof(*frame));
450         int err = 0;
451 
452         if (!frame)
453                 return 1;
454 
455         /*
456          * Set uc.uc_flags to a value which sc.trap_no would never have.
457          */
458         err = __put_user(0x5ac3c35a, &frame->uc.uc_flags);
459 
460         err |= setup_sigframe(frame, regs, set);
461         if (err == 0)
462                 err = setup_return(regs, ksig, frame->retcode, frame);
463 
464         return err;
465 }
466 
467 static int
468 setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs)
469 {
470         struct rt_sigframe __user *frame = get_sigframe(ksig, regs, sizeof(*frame));
471         int err = 0;
472 
473         if (!frame)
474                 return 1;
475 
476         err |= copy_siginfo_to_user(&frame->info, &ksig->info);
477 
478         err |= __put_user(0, &frame->sig.uc.uc_flags);
479         err |= __put_user(NULL, &frame->sig.uc.uc_link);
480 
481         err |= __save_altstack(&frame->sig.uc.uc_stack, regs->ARM_sp);
482         err |= setup_sigframe(&frame->sig, regs, set);
483         if (err == 0)
484                 err = setup_return(regs, ksig, frame->sig.retcode, frame);
485 
486         if (err == 0) {
487                 /*
488                  * For realtime signals we must also set the second and third
489                  * arguments for the signal handler.
490                  *   -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06
491                  */
492                 regs->ARM_r1 = (unsigned long)&frame->info;
493                 regs->ARM_r2 = (unsigned long)&frame->sig.uc;
494         }
495 
496         return err;
497 }
498 
499 /*
500  * OK, we're invoking a handler
501  */     
502 static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
503 {
504         sigset_t *oldset = sigmask_to_save();
505         int ret;
506 
507         /*
508          * Perform fixup for the pre-signal frame.
509          */
510         rseq_signal_deliver(ksig, regs);
511 
512         /*
513          * Set up the stack frame
514          */
515         if (ksig->ka.sa.sa_flags & SA_SIGINFO)
516                 ret = setup_rt_frame(ksig, oldset, regs);
517         else
518                 ret = setup_frame(ksig, oldset, regs);
519 
520         /*
521          * Check that the resulting registers are actually sane.
522          */
523         ret |= !valid_user_regs(regs);
524 
525         signal_setup_done(ret, ksig, 0);
526 }
527 
528 /*
529  * Note that 'init' is a special process: it doesn't get signals it doesn't
530  * want to handle. Thus you cannot kill init even with a SIGKILL even by
531  * mistake.
532  *
533  * Note that we go through the signals twice: once to check the signals that
534  * the kernel can handle, and then we build all the user-level signal handling
535  * stack-frames in one go after that.
536  */
537 static int do_signal(struct pt_regs *regs, int syscall)
538 {
539         unsigned int retval = 0, continue_addr = 0, restart_addr = 0;
540         struct ksignal ksig;
541         int restart = 0;
542 
543         /*
544          * If we were from a system call, check for system call restarting...
545          */
546         if (syscall) {
547                 continue_addr = regs->ARM_pc;
548                 restart_addr = continue_addr - (thumb_mode(regs) ? 2 : 4);
549                 retval = regs->ARM_r0;
550 
551                 /*
552                  * Prepare for system call restart.  We do this here so that a
553                  * debugger will see the already changed PSW.
554                  */
555                 switch (retval) {
556                 case -ERESTART_RESTARTBLOCK:
557                         restart -= 2;
558                         fallthrough;
559                 case -ERESTARTNOHAND:
560                 case -ERESTARTSYS:
561                 case -ERESTARTNOINTR:
562                         restart++;
563                         regs->ARM_r0 = regs->ARM_ORIG_r0;
564                         regs->ARM_pc = restart_addr;
565                         break;
566                 }
567         }
568 
569         /*
570          * Get the signal to deliver.  When running under ptrace, at this
571          * point the debugger may change all our registers ...
572          */
573         /*
574          * Depending on the signal settings we may need to revert the
575          * decision to restart the system call.  But skip this if a
576          * debugger has chosen to restart at a different PC.
577          */
578         if (get_signal(&ksig)) {
579                 /* handler */
580                 if (unlikely(restart) && regs->ARM_pc == restart_addr) {
581                         if (retval == -ERESTARTNOHAND ||
582                             retval == -ERESTART_RESTARTBLOCK
583                             || (retval == -ERESTARTSYS
584                                 && !(ksig.ka.sa.sa_flags & SA_RESTART))) {
585                                 regs->ARM_r0 = -EINTR;
586                                 regs->ARM_pc = continue_addr;
587                         }
588                 }
589                 handle_signal(&ksig, regs);
590         } else {
591                 /* no handler */
592                 restore_saved_sigmask();
593                 if (unlikely(restart) && regs->ARM_pc == restart_addr) {
594                         regs->ARM_pc = continue_addr;
595                         return restart;
596                 }
597         }
598         return 0;
599 }
600 
601 asmlinkage int
602 do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
603 {
604         /*
605          * The assembly code enters us with IRQs off, but it hasn't
606          * informed the tracing code of that for efficiency reasons.
607          * Update the trace code with the current status.
608          */
609         trace_hardirqs_off();
610         do {
611                 if (likely(thread_flags & _TIF_NEED_RESCHED)) {
612                         schedule();
613                 } else {
614                         if (unlikely(!user_mode(regs)))
615                                 return 0;
616                         local_irq_enable();
617                         if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) {
618                                 int restart = do_signal(regs, syscall);
619                                 if (unlikely(restart)) {
620                                         /*
621                                          * Restart without handlers.
622                                          * Deal with it without leaving
623                                          * the kernel space.
624                                          */
625                                         return restart;
626                                 }
627                                 syscall = 0;
628                         } else if (thread_flags & _TIF_UPROBE) {
629                                 uprobe_notify_resume(regs);
630                         } else {
631                                 resume_user_mode_work(regs);
632                         }
633                 }
634                 local_irq_disable();
635                 thread_flags = read_thread_flags();
636         } while (thread_flags & _TIF_WORK_MASK);
637         return 0;
638 }
639 
640 struct page *get_signal_page(void)
641 {
642         unsigned long ptr;
643         unsigned offset;
644         struct page *page;
645         void *addr;
646 
647         page = alloc_pages(GFP_KERNEL, 0);
648 
649         if (!page)
650                 return NULL;
651 
652         addr = page_address(page);
653 
654         /* Poison the entire page */
655         memset32(addr, __opcode_to_mem_arm(0xe7fddef1),
656                  PAGE_SIZE / sizeof(u32));
657 
658         /* Give the signal return code some randomness */
659         offset = 0x200 + (get_random_u16() & 0x7fc);
660         signal_return_offset = offset;
661 
662         /* Copy signal return handlers into the page */
663         memcpy(addr + offset, sigreturn_codes, sizeof(sigreturn_codes));
664 
665         /* Flush out all instructions in this page */
666         ptr = (unsigned long)addr;
667         flush_icache_range(ptr, ptr + PAGE_SIZE);
668 
669         return page;
670 }
671 
672 #ifdef CONFIG_DEBUG_RSEQ
673 asmlinkage void do_rseq_syscall(struct pt_regs *regs)
674 {
675         rseq_syscall(regs);
676 }
677 #endif
678 
679 /*
680  * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
681  * changes likely come with new fields that should be added below.
682  */
683 static_assert(NSIGILL   == 11);
684 static_assert(NSIGFPE   == 15);
685 static_assert(NSIGSEGV  == 10);
686 static_assert(NSIGBUS   == 5);
687 static_assert(NSIGTRAP  == 6);
688 static_assert(NSIGCHLD  == 6);
689 static_assert(NSIGSYS   == 2);
690 static_assert(sizeof(siginfo_t) == 128);
691 static_assert(__alignof__(siginfo_t) == 4);
692 static_assert(offsetof(siginfo_t, si_signo)     == 0x00);
693 static_assert(offsetof(siginfo_t, si_errno)     == 0x04);
694 static_assert(offsetof(siginfo_t, si_code)      == 0x08);
695 static_assert(offsetof(siginfo_t, si_pid)       == 0x0c);
696 static_assert(offsetof(siginfo_t, si_uid)       == 0x10);
697 static_assert(offsetof(siginfo_t, si_tid)       == 0x0c);
698 static_assert(offsetof(siginfo_t, si_overrun)   == 0x10);
699 static_assert(offsetof(siginfo_t, si_status)    == 0x14);
700 static_assert(offsetof(siginfo_t, si_utime)     == 0x18);
701 static_assert(offsetof(siginfo_t, si_stime)     == 0x1c);
702 static_assert(offsetof(siginfo_t, si_value)     == 0x14);
703 static_assert(offsetof(siginfo_t, si_int)       == 0x14);
704 static_assert(offsetof(siginfo_t, si_ptr)       == 0x14);
705 static_assert(offsetof(siginfo_t, si_addr)      == 0x0c);
706 static_assert(offsetof(siginfo_t, si_addr_lsb)  == 0x10);
707 static_assert(offsetof(siginfo_t, si_lower)     == 0x14);
708 static_assert(offsetof(siginfo_t, si_upper)     == 0x18);
709 static_assert(offsetof(siginfo_t, si_pkey)      == 0x14);
710 static_assert(offsetof(siginfo_t, si_perf_data) == 0x10);
711 static_assert(offsetof(siginfo_t, si_perf_type) == 0x14);
712 static_assert(offsetof(siginfo_t, si_perf_flags) == 0x18);
713 static_assert(offsetof(siginfo_t, si_band)      == 0x0c);
714 static_assert(offsetof(siginfo_t, si_fd)        == 0x10);
715 static_assert(offsetof(siginfo_t, si_call_addr) == 0x0c);
716 static_assert(offsetof(siginfo_t, si_syscall)   == 0x10);
717 static_assert(offsetof(siginfo_t, si_arch)      == 0x14);
718 

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