2 * signal32.c: Support 32bit signal syscalls.
4 * Copyright (C) 2001 IBM
5 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
6 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
8 * These routines maintain argument size conversion between 32bit and 64bit
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
17 #include <linux/config.h>
18 #include <linux/sched.h>
20 #include <linux/smp.h>
21 #include <linux/smp_lock.h>
22 #include <linux/kernel.h>
23 #include <linux/signal.h>
24 #include <linux/syscalls.h>
25 #include <linux/errno.h>
26 #include <linux/elf.h>
27 #include <linux/compat.h>
28 #include <asm/ppc32.h>
29 #include <asm/uaccess.h>
30 #include <asm/ppcdebug.h>
31 #include <asm/unistd.h>
32 #include <asm/cacheflush.h>
36 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
38 #define GP_REGS_SIZE32 min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
41 * When we have signals to deliver, we set up on the
42 * user stack, going down from the original stack pointer:
44 * a sigcontext32 struct
45 * a gap of __SIGNAL_FRAMESIZE32 bytes
47 * Each of these things must be a multiple of 16 bytes in size.
51 struct mcontext32 mctx; /* all the register values */
53 * Programs using the rs6000/xcoff abi can save up to 19 gp
54 * regs and 18 fp regs below sp before decrementing it.
59 /* We use the mc_pad field for the signal return trampoline. */
63 * When we have rt signals to deliver, we set up on the
64 * user stack, going down from the original stack pointer:
65 * one rt_sigframe32 struct (siginfo + ucontext + ABI gap)
66 * a gap of __SIGNAL_FRAMESIZE32+16 bytes
67 * (the +16 is to get the siginfo and ucontext32 in the same
68 * positions as in older kernels).
70 * Each of these things must be a multiple of 16 bytes in size.
73 struct rt_sigframe32 {
74 struct compat_siginfo info;
77 * Programs using the rs6000/xcoff abi can save up to 19 gp
78 * regs and 18 fp regs below sp before decrementing it.
85 * Common utility functions used by signal and context support
90 * Restore the user process's signal mask
91 * (implemented in signal.c)
93 extern void restore_sigmask(sigset_t *set);
96 * Functions for flipping sigsets (thanks to brain dead generic
97 * implementation that makes things simple for little endian only
99 static inline void compat_from_sigset(compat_sigset_t *compat, sigset_t *set)
101 switch (_NSIG_WORDS) {
102 case 4: compat->sig[5] = set->sig[3] & 0xffffffffull ;
103 compat->sig[7] = set->sig[3] >> 32;
104 case 3: compat->sig[4] = set->sig[2] & 0xffffffffull ;
105 compat->sig[5] = set->sig[2] >> 32;
106 case 2: compat->sig[2] = set->sig[1] & 0xffffffffull ;
107 compat->sig[3] = set->sig[1] >> 32;
108 case 1: compat->sig[0] = set->sig[0] & 0xffffffffull ;
109 compat->sig[1] = set->sig[0] >> 32;
113 static inline void sigset_from_compat(sigset_t *set, compat_sigset_t *compat)
115 switch (_NSIG_WORDS) {
116 case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32);
117 case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32);
118 case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32);
119 case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32);
125 * Save the current user registers on the user stack.
126 * We only save the altivec registers if the process has used
127 * altivec instructions at some point.
129 static int save_user_regs(struct pt_regs *regs, struct mcontext32 __user *frame, int sigret)
131 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
134 /* Make sure floating point registers are stored in regs */
135 flush_fp_to_thread(current);
137 /* save general and floating-point registers */
138 for (i = 0; i <= PT_RESULT; i ++)
139 err |= __put_user((unsigned int)gregs[i], &frame->mc_gregs[i]);
140 err |= __copy_to_user(&frame->mc_fregs, current->thread.fpr,
141 ELF_NFPREG * sizeof(double));
145 current->thread.fpscr = 0; /* turn off all fp exceptions */
147 #ifdef CONFIG_ALTIVEC
148 /* save altivec registers */
149 if (current->thread.used_vr) {
150 flush_altivec_to_thread(current);
151 if (__copy_to_user(&frame->mc_vregs, current->thread.vr,
152 ELF_NVRREG32 * sizeof(vector128)))
154 /* set MSR_VEC in the saved MSR value to indicate that
155 frame->mc_vregs contains valid data */
156 if (__put_user(regs->msr | MSR_VEC, &frame->mc_gregs[PT_MSR]))
159 /* else assert((regs->msr & MSR_VEC) == 0) */
161 /* We always copy to/from vrsave, it's 0 if we don't have or don't
162 * use altivec. Since VSCR only contains 32 bits saved in the least
163 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
164 * most significant bits of that same vector. --BenH
166 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
168 #endif /* CONFIG_ALTIVEC */
171 /* Set up the sigreturn trampoline: li r0,sigret; sc */
172 if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
173 || __put_user(0x44000002UL, &frame->tramp[1]))
175 flush_icache_range((unsigned long) &frame->tramp[0],
176 (unsigned long) &frame->tramp[2]);
183 * Restore the current user register values from the user stack,
186 static long restore_user_regs(struct pt_regs *regs,
187 struct mcontext32 __user *sr, int sig)
189 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
192 unsigned int save_r2;
193 #ifdef CONFIG_ALTIVEC
198 * restore general registers but not including MSR or SOFTE. Also
199 * take care of keeping r2 (TLS) intact if not a signal
202 save_r2 = (unsigned int)regs->gpr[2];
203 for (i = 0; i <= PT_RESULT; i++) {
204 if ((i == PT_MSR) || (i == PT_SOFTE))
206 err |= __get_user(gregs[i], &sr->mc_gregs[i]);
209 regs->gpr[2] = (unsigned long) save_r2;
213 /* force the process to reload the FP registers from
214 current->thread when it next does FP instructions */
215 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
216 if (__copy_from_user(current->thread.fpr, &sr->mc_fregs,
217 sizeof(sr->mc_fregs)))
220 #ifdef CONFIG_ALTIVEC
221 /* force the process to reload the altivec registers from
222 current->thread when it next does altivec instructions */
223 regs->msr &= ~MSR_VEC;
224 if (!__get_user(msr, &sr->mc_gregs[PT_MSR]) && (msr & MSR_VEC) != 0) {
225 /* restore altivec registers from the stack */
226 if (__copy_from_user(current->thread.vr, &sr->mc_vregs,
227 sizeof(sr->mc_vregs)))
229 } else if (current->thread.used_vr)
230 memset(¤t->thread.vr, 0, ELF_NVRREG32 * sizeof(vector128));
232 /* Always get VRSAVE back */
233 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
235 #endif /* CONFIG_ALTIVEC */
242 * Start of nonRT signal support
244 * sigset_t is 32 bits for non-rt signals
247 * sigaction sys32_sigaction
248 * sigreturn sys32_sigreturn
250 * Note sigsuspend has no special 32 bit routine - uses the 64 bit routine
257 * Atomically swap in the new signal mask, and wait for a signal.
259 long sys32_sigsuspend(old_sigset_t mask, int p2, int p3, int p4, int p6, int p7,
260 struct pt_regs *regs)
265 spin_lock_irq(¤t->sighand->siglock);
266 saveset = current->blocked;
267 siginitset(¤t->blocked, mask);
269 spin_unlock_irq(¤t->sighand->siglock);
271 regs->result = -EINTR;
272 regs->gpr[3] = EINTR;
273 regs->ccr |= 0x10000000;
275 current->state = TASK_INTERRUPTIBLE;
277 if (do_signal32(&saveset, regs))
279 * If a signal handler needs to be called,
280 * do_signal32() has set R3 to the signal number (the
281 * first argument of the signal handler), so don't
282 * overwrite that with EINTR !
283 * In the other cases, do_signal32() doesn't touch
284 * R3, so it's still set to -EINTR (see above).
290 long sys32_sigaction(int sig, struct old_sigaction32 __user *act,
291 struct old_sigaction32 __user *oact)
293 struct k_sigaction new_ka, old_ka;
300 compat_old_sigset_t mask;
302 if (get_user((long)new_ka.sa.sa_handler, &act->sa_handler) ||
303 __get_user((long)new_ka.sa.sa_restorer, &act->sa_restorer) ||
304 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
305 __get_user(mask, &act->sa_mask))
307 siginitset(&new_ka.sa.sa_mask, mask);
310 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
312 if (put_user((long)old_ka.sa.sa_handler, &oact->sa_handler) ||
313 __put_user((long)old_ka.sa.sa_restorer, &oact->sa_restorer) ||
314 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
315 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
325 * Start of RT signal support
327 * sigset_t is 64 bits for rt signals
330 * sigaction sys32_rt_sigaction
331 * sigpending sys32_rt_sigpending
332 * sigprocmask sys32_rt_sigprocmask
333 * sigreturn sys32_rt_sigreturn
334 * sigtimedwait sys32_rt_sigtimedwait
335 * sigqueueinfo sys32_rt_sigqueueinfo
336 * sigsuspend sys32_rt_sigsuspend
340 * copy_siginfo_to_user32
345 long sys32_rt_sigaction(int sig, const struct sigaction32 __user *act,
346 struct sigaction32 __user *oact, size_t sigsetsize)
348 struct k_sigaction new_ka, old_ka;
350 compat_sigset_t set32;
352 /* XXX: Don't preclude handling different sized sigset_t's. */
353 if (sigsetsize != sizeof(compat_sigset_t))
357 ret = get_user((long)new_ka.sa.sa_handler, &act->sa_handler);
358 ret |= __copy_from_user(&set32, &act->sa_mask,
359 sizeof(compat_sigset_t));
360 sigset_from_compat(&new_ka.sa.sa_mask, &set32);
361 ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
366 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
368 compat_from_sigset(&set32, &old_ka.sa.sa_mask);
369 ret = put_user((long)old_ka.sa.sa_handler, &oact->sa_handler);
370 ret |= __copy_to_user(&oact->sa_mask, &set32,
371 sizeof(compat_sigset_t));
372 ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
378 * Note: it is necessary to treat how as an unsigned int, with the
379 * corresponding cast to a signed int to insure that the proper
380 * conversion (sign extension) between the register representation
381 * of a signed int (msr in 32-bit mode) and the register representation
382 * of a signed int (msr in 64-bit mode) is performed.
384 long sys32_rt_sigprocmask(u32 how, compat_sigset_t __user *set,
385 compat_sigset_t __user *oset, size_t sigsetsize)
391 mm_segment_t old_fs = get_fs();
394 if (copy_from_user (&s32, set, sizeof(compat_sigset_t)))
396 sigset_from_compat(&s, &s32);
400 /* This is valid because of the set_fs() */
401 up = (sigset_t __user *) &s;
402 ret = sys_rt_sigprocmask((int)how, set ? up : NULL, oset ? up : NULL,
408 compat_from_sigset(&s32, &s);
409 if (copy_to_user (oset, &s32, sizeof(compat_sigset_t)))
415 long sys32_rt_sigpending(compat_sigset_t __user *set, compat_size_t sigsetsize)
420 mm_segment_t old_fs = get_fs();
423 /* The __user pointer cast is valid because of the set_fs() */
424 ret = sys_rt_sigpending((sigset_t __user *) &s, sigsetsize);
427 compat_from_sigset(&s32, &s);
428 if (copy_to_user (set, &s32, sizeof(compat_sigset_t)))
435 static long copy_siginfo_to_user32(compat_siginfo_t __user *d, siginfo_t *s)
439 if (!access_ok (VERIFY_WRITE, d, sizeof(*d)))
442 /* If you change siginfo_t structure, please be sure
443 * this code is fixed accordingly.
444 * It should never copy any pad contained in the structure
445 * to avoid security leaks, but must copy the generic
446 * 3 ints plus the relevant union member.
447 * This routine must convert siginfo from 64bit to 32bit as well
450 err = __put_user(s->si_signo, &d->si_signo);
451 err |= __put_user(s->si_errno, &d->si_errno);
452 err |= __put_user((short)s->si_code, &d->si_code);
454 err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad,
456 else switch(s->si_code >> 16) {
457 case __SI_CHLD >> 16:
458 err |= __put_user(s->si_pid, &d->si_pid);
459 err |= __put_user(s->si_uid, &d->si_uid);
460 err |= __put_user(s->si_utime, &d->si_utime);
461 err |= __put_user(s->si_stime, &d->si_stime);
462 err |= __put_user(s->si_status, &d->si_status);
464 case __SI_FAULT >> 16:
465 err |= __put_user((unsigned int)(unsigned long)s->si_addr,
468 case __SI_POLL >> 16:
469 case __SI_TIMER >> 16:
470 err |= __put_user(s->si_band, &d->si_band);
471 err |= __put_user(s->si_fd, &d->si_fd);
473 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
474 case __SI_MESGQ >> 16:
475 err |= __put_user(s->si_int, &d->si_int);
477 case __SI_KILL >> 16:
479 err |= __put_user(s->si_pid, &d->si_pid);
480 err |= __put_user(s->si_uid, &d->si_uid);
486 long sys32_rt_sigtimedwait(compat_sigset_t __user *uthese, compat_siginfo_t __user *uinfo,
487 struct compat_timespec __user *uts, compat_size_t sigsetsize)
493 mm_segment_t old_fs = get_fs();
496 if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
498 sigset_from_compat(&s, &s32);
499 if (uts && get_compat_timespec(&t, uts))
502 /* The __user pointer casts are valid because of the set_fs() */
503 ret = sys_rt_sigtimedwait((sigset_t __user *) &s,
504 uinfo ? (siginfo_t __user *) &info : NULL,
505 uts ? (struct timespec __user *) &t : NULL,
508 if (ret >= 0 && uinfo) {
509 if (copy_siginfo_to_user32(uinfo, &info))
516 * Note: it is necessary to treat pid and sig as unsigned ints, with the
517 * corresponding cast to a signed int to insure that the proper conversion
518 * (sign extension) between the register representation of a signed int
519 * (msr in 32-bit mode) and the register representation of a signed int
520 * (msr in 64-bit mode) is performed.
522 long sys32_rt_sigqueueinfo(u32 pid, u32 sig, compat_siginfo_t __user *uinfo)
526 mm_segment_t old_fs = get_fs();
528 if (copy_from_user (&info, uinfo, 3*sizeof(int)) ||
529 copy_from_user (info._sifields._pad, uinfo->_sifields._pad, SI_PAD_SIZE32))
532 /* The __user pointer cast is valid becasuse of the set_fs() */
533 ret = sys_rt_sigqueueinfo((int)pid, (int)sig, (siginfo_t __user *) &info);
538 int sys32_rt_sigsuspend(compat_sigset_t __user * unewset, size_t sigsetsize, int p3,
539 int p4, int p6, int p7, struct pt_regs *regs)
541 sigset_t saveset, newset;
544 /* XXX: Don't preclude handling different sized sigset_t's. */
545 if (sigsetsize != sizeof(sigset_t))
548 if (copy_from_user(&s32, unewset, sizeof(s32)))
552 * Swap the 2 words of the 64-bit sigset_t (they are stored
553 * in the "wrong" endian in 32-bit user storage).
555 sigset_from_compat(&newset, &s32);
557 sigdelsetmask(&newset, ~_BLOCKABLE);
558 spin_lock_irq(¤t->sighand->siglock);
559 saveset = current->blocked;
560 current->blocked = newset;
562 spin_unlock_irq(¤t->sighand->siglock);
564 regs->result = -EINTR;
565 regs->gpr[3] = EINTR;
566 regs->ccr |= 0x10000000;
568 current->state = TASK_INTERRUPTIBLE;
570 if (do_signal32(&saveset, regs))
572 * If a signal handler needs to be called,
573 * do_signal32() has set R3 to the signal number (the
574 * first argument of the signal handler), so don't
575 * overwrite that with EINTR !
576 * In the other cases, do_signal32() doesn't touch
577 * R3, so it's still set to -EINTR (see above).
584 * Start Alternate signal stack support
587 * sigaltatck sys32_sigaltstack
590 int sys32_sigaltstack(u32 __new, u32 __old, int r5,
591 int r6, int r7, int r8, struct pt_regs *regs)
593 stack_32_t __user * newstack = (stack_32_t __user *)(long) __new;
594 stack_32_t __user * oldstack = (stack_32_t __user *)(long) __old;
601 * set sp to the user stack on entry to the system call
602 * the system call router sets R9 to the saved registers
606 /* Put new stack info in local 64 bit stack struct */
608 (get_user((long)uss.ss_sp, &newstack->ss_sp) ||
609 __get_user(uss.ss_flags, &newstack->ss_flags) ||
610 __get_user(uss.ss_size, &newstack->ss_size)))
615 /* The __user pointer casts are valid because of the set_fs() */
616 ret = do_sigaltstack(
617 newstack ? (stack_t __user *) &uss : NULL,
618 oldstack ? (stack_t __user *) &uoss : NULL,
621 /* Copy the stack information to the user output buffer */
622 if (!ret && oldstack &&
623 (put_user((long)uoss.ss_sp, &oldstack->ss_sp) ||
624 __put_user(uoss.ss_flags, &oldstack->ss_flags) ||
625 __put_user(uoss.ss_size, &oldstack->ss_size)))
632 * Set up a signal frame for a "real-time" signal handler
633 * (one which gets siginfo).
635 static void handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
636 siginfo_t *info, sigset_t *oldset,
637 struct pt_regs * regs, unsigned long newsp)
639 struct rt_sigframe32 __user *rt_sf;
640 struct mcontext32 __user *frame;
641 unsigned long origsp = newsp;
642 compat_sigset_t c_oldset;
644 /* Set up Signal Frame */
645 /* Put a Real Time Context onto stack */
646 newsp -= sizeof(*rt_sf);
647 rt_sf = (struct rt_sigframe32 __user *)newsp;
649 /* create a stack frame for the caller of the handler */
650 newsp -= __SIGNAL_FRAMESIZE32 + 16;
652 if (verify_area(VERIFY_WRITE, (void __user *)newsp, origsp - newsp))
655 compat_from_sigset(&c_oldset, oldset);
657 /* Put the siginfo & fill in most of the ucontext */
658 if (copy_siginfo_to_user32(&rt_sf->info, info)
659 || __put_user(0, &rt_sf->uc.uc_flags)
660 || __put_user(0, &rt_sf->uc.uc_link)
661 || __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)
662 || __put_user(sas_ss_flags(regs->gpr[1]),
663 &rt_sf->uc.uc_stack.ss_flags)
664 || __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size)
665 || __put_user((u32)(u64)&rt_sf->uc.uc_mcontext, &rt_sf->uc.uc_regs)
666 || __copy_to_user(&rt_sf->uc.uc_sigmask, &c_oldset, sizeof(c_oldset)))
669 /* Save user registers on the stack */
670 frame = &rt_sf->uc.uc_mcontext;
671 if (save_user_regs(regs, frame, __NR_rt_sigreturn))
674 if (put_user(regs->gpr[1], (unsigned long __user *)newsp))
676 regs->gpr[1] = (unsigned long) newsp;
678 regs->gpr[4] = (unsigned long) &rt_sf->info;
679 regs->gpr[5] = (unsigned long) &rt_sf->uc;
680 regs->gpr[6] = (unsigned long) rt_sf;
681 regs->nip = (unsigned long) ka->sa.sa_handler;
682 regs->link = (unsigned long) frame->tramp;
690 printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n",
694 ka->sa.sa_handler = SIG_DFL;
695 force_sig(SIGSEGV, current);
698 static long do_setcontext32(struct ucontext32 __user *ucp, struct pt_regs *regs, int sig)
700 compat_sigset_t c_set;
704 if (__copy_from_user(&c_set, &ucp->uc_sigmask, sizeof(c_set))
705 || __get_user(mcp, &ucp->uc_regs))
707 sigset_from_compat(&set, &c_set);
708 restore_sigmask(&set);
709 if (restore_user_regs(regs, (struct mcontext32 __user *)(u64)mcp, sig))
716 * Handle {get,set,swap}_context operations for 32 bits processes
719 long sys32_swapcontext(struct ucontext32 __user *old_ctx,
720 struct ucontext32 __user *new_ctx,
721 int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
724 compat_sigset_t c_set;
726 /* Context size is for future use. Right now, we only make sure
727 * we are passed something we understand
729 if (ctx_size < sizeof(struct ucontext32))
732 if (old_ctx != NULL) {
733 compat_from_sigset(&c_set, ¤t->blocked);
734 if (verify_area(VERIFY_WRITE, old_ctx, sizeof(*old_ctx))
735 || save_user_regs(regs, &old_ctx->uc_mcontext, 0)
736 || __copy_to_user(&old_ctx->uc_sigmask, &c_set, sizeof(c_set))
737 || __put_user((u32)(u64)&old_ctx->uc_mcontext, &old_ctx->uc_regs))
742 if (verify_area(VERIFY_READ, new_ctx, sizeof(*new_ctx))
743 || __get_user(tmp, (u8 __user *) new_ctx)
744 || __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1))
748 * If we get a fault copying the context into the kernel's
749 * image of the user's registers, we can't just return -EFAULT
750 * because the user's registers will be corrupted. For instance
751 * the NIP value may have been updated but not some of the
752 * other registers. Given that we have done the verify_area
753 * and successfully read the first and last bytes of the region
754 * above, this should only happen in an out-of-memory situation
755 * or if another thread unmaps the region containing the context.
756 * We kill the task with a SIGSEGV in this situation.
758 if (do_setcontext32(new_ctx, regs, 0))
764 long sys32_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
765 struct pt_regs *regs)
767 struct rt_sigframe32 __user *rt_sf;
771 /* Always make any pending restarted system calls return -EINTR */
772 current_thread_info()->restart_block.fn = do_no_restart_syscall;
774 rt_sf = (struct rt_sigframe32 __user *)
775 (regs->gpr[1] + __SIGNAL_FRAMESIZE32 + 16);
776 if (verify_area(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
778 if (do_setcontext32(&rt_sf->uc, regs, 1))
782 * It's not clear whether or why it is desirable to save the
783 * sigaltstack setting on signal delivery and restore it on
784 * signal return. But other architectures do this and we have
785 * always done it up until now so it is probably better not to
786 * change it. -- paulus
787 * We use the sys32_ version that does the 32/64 bits conversion
788 * and takes userland pointer directly. What about error checking ?
791 sys32_sigaltstack((u32)(u64)&rt_sf->uc.uc_stack, 0, 0, 0, 0, 0, regs);
798 force_sig(SIGSEGV, current);
804 * OK, we're invoking a handler
806 static void handle_signal32(unsigned long sig, struct k_sigaction *ka,
807 siginfo_t *info, sigset_t *oldset,
808 struct pt_regs * regs, unsigned long newsp)
810 struct sigcontext32 __user *sc;
811 struct sigregs32 __user *frame;
812 unsigned long origsp = newsp;
814 /* Set up Signal Frame */
815 newsp -= sizeof(struct sigregs32);
816 frame = (struct sigregs32 __user *) newsp;
818 /* Put a sigcontext on the stack */
819 newsp -= sizeof(*sc);
820 sc = (struct sigcontext32 __user *) newsp;
822 /* create a stack frame for the caller of the handler */
823 newsp -= __SIGNAL_FRAMESIZE32;
825 if (verify_area(VERIFY_WRITE, (void __user *) newsp, origsp - newsp))
829 #error "Please adjust handle_signal32()"
831 if (__put_user((u32)(u64)ka->sa.sa_handler, &sc->handler)
832 || __put_user(oldset->sig[0], &sc->oldmask)
833 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
834 || __put_user((u32)(u64)frame, &sc->regs)
835 || __put_user(sig, &sc->signal))
838 if (save_user_regs(regs, &frame->mctx, __NR_sigreturn))
841 if (put_user(regs->gpr[1], (unsigned long __user *)newsp))
843 regs->gpr[1] = (unsigned long) newsp;
845 regs->gpr[4] = (unsigned long) sc;
846 regs->nip = (unsigned long) ka->sa.sa_handler;
847 regs->link = (unsigned long) frame->mctx.tramp;
855 printk("badframe in handle_signal, regs=%p frame=%x newsp=%x\n",
856 regs, frame, *newspp);
859 ka->sa.sa_handler = SIG_DFL;
860 force_sig(SIGSEGV, current);
864 * Do a signal return; undo the signal stack.
866 long sys32_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
867 struct pt_regs *regs)
869 struct sigcontext32 __user *sc;
870 struct sigcontext32 sigctx;
871 struct mcontext32 __user *sr;
875 /* Always make any pending restarted system calls return -EINTR */
876 current_thread_info()->restart_block.fn = do_no_restart_syscall;
878 sc = (struct sigcontext32 __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE32);
879 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
883 * Note that PPC32 puts the upper 32 bits of the sigmask in the
884 * unused part of the signal stackframe
886 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
887 restore_sigmask(&set);
889 sr = (struct mcontext32 __user *)(u64)sigctx.regs;
890 if (verify_area(VERIFY_READ, sr, sizeof(*sr))
891 || restore_user_regs(regs, sr, 1))
898 force_sig(SIGSEGV, current);
905 * Start of do_signal32 routine
907 * This routine gets control when a pending signal needs to be processed
908 * in the 32 bit target thread -
910 * It handles both rt and non-rt signals
914 * Note that 'init' is a special process: it doesn't get signals it doesn't
915 * want to handle. Thus you cannot kill init even with a SIGKILL even by
919 int do_signal32(sigset_t *oldset, struct pt_regs *regs)
922 struct k_sigaction *ka;
923 unsigned int frame, newsp;
927 oldset = ¤t->blocked;
931 signr = get_signal_to_deliver(&info, regs, NULL);
933 ka = (signr == 0)? NULL: ¤t->sighand->action[signr-1];
935 if (TRAP(regs) == 0x0C00 /* System Call! */
936 && regs->ccr & 0x10000000 /* error signalled */
937 && ((ret = regs->gpr[3]) == ERESTARTSYS
938 || ret == ERESTARTNOHAND || ret == ERESTARTNOINTR
939 || ret == ERESTART_RESTARTBLOCK)) {
942 && (ret == ERESTARTNOHAND || ret == ERESTART_RESTARTBLOCK
943 || (ret == ERESTARTSYS
944 && !(ka->sa.sa_flags & SA_RESTART)))) {
945 /* make the system call return an EINTR error */
946 regs->result = -EINTR;
947 regs->gpr[3] = EINTR;
948 /* note that the cr0.SO bit is already set */
950 regs->nip -= 4; /* Back up & retry system call */
953 if (ret == ERESTART_RESTARTBLOCK)
954 regs->gpr[0] = __NR_restart_syscall;
956 regs->gpr[3] = regs->orig_gpr3;
961 return 0; /* no signals delivered */
963 if ((ka->sa.sa_flags & SA_ONSTACK) && current->sas_ss_size
964 && (!on_sig_stack(regs->gpr[1])))
965 newsp = (current->sas_ss_sp + current->sas_ss_size);
967 newsp = regs->gpr[1];
970 /* Whee! Actually deliver the signal. */
971 if (ka->sa.sa_flags & SA_SIGINFO)
972 handle_rt_signal32(signr, ka, &info, oldset, regs, newsp);
974 handle_signal32(signr, ka, &info, oldset, regs, newsp);
976 if (ka->sa.sa_flags & SA_ONESHOT)
977 ka->sa.sa_handler = SIG_DFL;
979 if (!(ka->sa.sa_flags & SA_NODEFER)) {
980 spin_lock_irq(¤t->sighand->siglock);
981 sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
982 sigaddset(¤t->blocked, signr);
984 spin_unlock_irq(¤t->sighand->siglock);