arch/x86_64/ia32/ia32_signal.c - kernel/msm-4.19 - Gitiles

 /*
  *  linux/arch/x86_64/ia32/ia32_signal.c
  *
  *  Copyright (C) 1991, 1992  Linus Torvalds
  *
  *  1997-11-28  Modified for POSIX.1b signals by Richard Henderson
  *  2000-06-20  Pentium III FXSR, SSE support by Gareth Hughes
  *  2000-12-*   x86-64 compatibility mode signal handling by Andi Kleen
  */

 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
 #include <linux/smp_lock.h>
 #include <linux/kernel.h>
 #include <linux/signal.h>
 #include <linux/errno.h>
 #include <linux/wait.h>
 #include <linux/ptrace.h>
 #include <linux/unistd.h>
 #include <linux/stddef.h>
 #include <linux/personality.h>
 #include <linux/compat.h>
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
 #include <asm/i387.h>
 #include <asm/ia32.h>
 #include <asm/ptrace.h>
 #include <asm/ia32_unistd.h>
 #include <asm/user32.h>
 #include <asm/sigcontext32.h>
 #include <asm/fpu32.h>
 #include <asm/proto.h>
 #include <asm/vsyscall32.h>

 #define DEBUG_SIG 0

 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

 asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset);
 void signal_fault(struct pt_regs *regs, void __user *frame, char *where);

 int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
 {
 	int err;
 	if (!access_ok (VERIFY_WRITE, to, sizeof(compat_siginfo_t)))
 		return -EFAULT;

 	/* If you change siginfo_t structure, please make sure that
 	   this code is fixed accordingly.
 	   It should never copy any pad contained in the structure
 	   to avoid security leaks, but must copy the generic
 	   3 ints plus the relevant union member.  */
 	err = __put_user(from->si_signo, &to->si_signo);
 	err |= __put_user(from->si_errno, &to->si_errno);
  	err |= __put_user((short)from->si_code, &to->si_code);

 	if (from->si_code < 0) {
 		err |= __put_user(from->si_pid, &to->si_pid);
  		err |= __put_user(from->si_uid, &to->si_uid);
  		err |= __put_user(ptr_to_compat(from->si_ptr), &to->si_ptr);
 	} else {
  		/* First 32bits of unions are always present:
  		 * si_pid === si_band === si_tid === si_addr(LS half) */
 		err |= __put_user(from->_sifields._pad[0], &to->_sifields._pad[0]);
 		switch (from->si_code >> 16) {
 		case __SI_FAULT >> 16:
 			break;
 		case __SI_CHLD >> 16:
 			err |= __put_user(from->si_utime, &to->si_utime);
 			err |= __put_user(from->si_stime, &to->si_stime);
 			err |= __put_user(from->si_status, &to->si_status);
 			/* FALL THROUGH */
 		default:
 		case __SI_KILL >> 16:
 			err |= __put_user(from->si_uid, &to->si_uid);
 			break;
 		case __SI_POLL >> 16:
 			err |= __put_user(from->si_fd, &to->si_fd);
 			break;
 		case __SI_TIMER >> 16:
 			err |= __put_user(from->si_overrun, &to->si_overrun);
 			err |= __put_user(ptr_to_compat(from->si_ptr),
 					&to->si_ptr);
 			break;
 		case __SI_RT >> 16: /* This is not generated by the kernel as of now.  */
 		case __SI_MESGQ >> 16:
 			err |= __put_user(from->si_uid, &to->si_uid);
 			err |= __put_user(from->si_int, &to->si_int);
 			break;
 		}
 	}
 	return err;
 }

 int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
 {
 	int err;
 	u32 ptr32;
 	if (!access_ok (VERIFY_READ, from, sizeof(compat_siginfo_t)))
 		return -EFAULT;

 	err = __get_user(to->si_signo, &from->si_signo);
 	err |= __get_user(to->si_errno, &from->si_errno);
 	err |= __get_user(to->si_code, &from->si_code);

 	err |= __get_user(to->si_pid, &from->si_pid);
 	err |= __get_user(to->si_uid, &from->si_uid);
 	err |= __get_user(ptr32, &from->si_ptr);
 	to->si_ptr = compat_ptr(ptr32);

 	return err;
 }

 asmlinkage long
 sys32_sigsuspend(int history0, int history1, old_sigset_t mask)
 {
 	mask &= _BLOCKABLE;
 	spin_lock_irq(&current->sighand->siglock);
 	current->saved_sigmask = current->blocked;
 	siginitset(&current->blocked, mask);
 	recalc_sigpending();
 	spin_unlock_irq(&current->sighand->siglock);

 	current->state = TASK_INTERRUPTIBLE;
 	schedule();
 	set_thread_flag(TIF_RESTORE_SIGMASK);
 	return -ERESTARTNOHAND;
 }

 asmlinkage long
 sys32_sigaltstack(const stack_ia32_t __user *uss_ptr,
 		  stack_ia32_t __user *uoss_ptr,
 		  struct pt_regs *regs)
 {
 	stack_t uss,uoss;
 	int ret;
 	mm_segment_t seg;
 	if (uss_ptr) {
 		u32 ptr;
 		memset(&uss,0,sizeof(stack_t));
 		if (!access_ok(VERIFY_READ,uss_ptr,sizeof(stack_ia32_t)) ||
 			    __get_user(ptr, &uss_ptr->ss_sp) ||
 			    __get_user(uss.ss_flags, &uss_ptr->ss_flags) ||
 			    __get_user(uss.ss_size, &uss_ptr->ss_size))
 			return -EFAULT;
 		uss.ss_sp = compat_ptr(ptr);
 	}
 	seg = get_fs();
 	set_fs(KERNEL_DS);
 	ret = do_sigaltstack(uss_ptr ? &uss : NULL, &uoss, regs->rsp);
 	set_fs(seg);
 	if (ret >= 0 && uoss_ptr)  {
 		if (!access_ok(VERIFY_WRITE,uoss_ptr,sizeof(stack_ia32_t)) ||
 		    __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) ||
 		    __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) ||
 		    __put_user(uoss.ss_size, &uoss_ptr->ss_size))
 			ret = -EFAULT;
 	}
 	return ret;
 }

 /*
  * Do a signal return; undo the signal stack.
  */

 struct sigframe
 {
 	u32 pretcode;
 	int sig;
 	struct sigcontext_ia32 sc;
 	struct _fpstate_ia32 fpstate;
 	unsigned int extramask[_COMPAT_NSIG_WORDS-1];
 	char retcode[8];
 };

 struct rt_sigframe
 {
 	u32 pretcode;
 	int sig;
 	u32 pinfo;
 	u32 puc;
 	compat_siginfo_t info;
 	struct ucontext_ia32 uc;
 	struct _fpstate_ia32 fpstate;
 	char retcode[8];
 };

 static int
 ia32_restore_sigcontext(struct pt_regs *regs, struct sigcontext_ia32 __user *sc, unsigned int *peax)
 {
 	unsigned int err = 0;

 	/* Always make any pending restarted system calls return -EINTR */
 	current_thread_info()->restart_block.fn = do_no_restart_syscall;

 #if DEBUG_SIG
 	printk("SIG restore_sigcontext: sc=%p err(%x) eip(%x) cs(%x) flg(%x)\n",
 		sc, sc->err, sc->eip, sc->cs, sc->eflags);
 #endif
 #define COPY(x)		{ \
 	unsigned int reg;			\
 	err |= __get_user(reg, &sc->e ##x);	\
 	regs->r ## x = reg;			\
 }

 #define RELOAD_SEG(seg,mask)						\
 	{ unsigned int cur; 						\
 	  unsigned short pre;						\
 	  err |= __get_user(pre, &sc->seg);				\
     	  asm volatile("movl %%" #seg ",%0" : "=r" (cur));		\
 	  pre |= mask; 							\
 	  if (pre != cur) loadsegment(seg,pre); }

 	/* Reload fs and gs if they have changed in the signal handler.
 	   This does not handle long fs/gs base changes in the handler, but
 	   does not clobber them at least in the normal case. */

 	{
 		unsigned gs, oldgs;
 		err |= __get_user(gs, &sc->gs);
 		gs |= 3;
 		asm("movl %%gs,%0" : "=r" (oldgs));
 		if (gs != oldgs)
 		load_gs_index(gs);
 	}
 	RELOAD_SEG(fs,3);
 	RELOAD_SEG(ds,3);
 	RELOAD_SEG(es,3);

 	COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
 	COPY(dx); COPY(cx); COPY(ip);
 	/* Don't touch extended registers */

 	err |= __get_user(regs->cs, &sc->cs);
 	regs->cs |= 3;
 	err |= __get_user(regs->ss, &sc->ss);
 	regs->ss |= 3;

 	{
 		unsigned int tmpflags;
 		err |= __get_user(tmpflags, &sc->eflags);
 		regs->eflags = (regs->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
 		regs->orig_rax = -1;		/* disable syscall checks */
 	}

 	{
 		u32 tmp;
 		struct _fpstate_ia32 __user * buf;
 		err |= __get_user(tmp, &sc->fpstate);
 		buf = compat_ptr(tmp);
 		if (buf) {
 			if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
 				goto badframe;
 			err |= restore_i387_ia32(current, buf, 0);
 		} else {
 			struct task_struct *me = current;
 			if (used_math()) {
 				clear_fpu(me);
 				clear_used_math();
 			}
 		}
 	}

 	{
 		u32 tmp;
 		err |= __get_user(tmp, &sc->eax);
 		*peax = tmp;
 	}
 	return err;

 badframe:
 	return 1;
 }

 asmlinkage long sys32_sigreturn(struct pt_regs *regs)
 {
 	struct sigframe __user *frame = (struct sigframe __user *)(regs->rsp-8);
 	sigset_t set;
 	unsigned int eax;

 	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 		goto badframe;
 	if (__get_user(set.sig[0], &frame->sc.oldmask)
 	    || (_COMPAT_NSIG_WORDS > 1
 		&& __copy_from_user((((char *) &set.sig) + 4), &frame->extramask,
 				    sizeof(frame->extramask))))
 		goto badframe;

 	sigdelsetmask(&set, ~_BLOCKABLE);
 	spin_lock_irq(&current->sighand->siglock);
 	current->blocked = set;
 	recalc_sigpending();
 	spin_unlock_irq(&current->sighand->siglock);

 	if (ia32_restore_sigcontext(regs, &frame->sc, &eax))
 		goto badframe;
 	return eax;

 badframe:
 	signal_fault(regs, frame, "32bit sigreturn");
 	return 0;
 }

 asmlinkage long sys32_rt_sigreturn(struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
 	sigset_t set;
 	unsigned int eax;
 	struct pt_regs tregs;

 	frame = (struct rt_sigframe __user *)(regs->rsp - 4);

 	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 		goto badframe;
 	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
 		goto badframe;

 	sigdelsetmask(&set, ~_BLOCKABLE);
 	spin_lock_irq(&current->sighand->siglock);
 	current->blocked = set;
 	recalc_sigpending();
 	spin_unlock_irq(&current->sighand->siglock);

 	if (ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax))
 		goto badframe;

 	tregs = *regs;
 	if (sys32_sigaltstack(&frame->uc.uc_stack, NULL, &tregs) == -EFAULT)
 		goto badframe;

 	return eax;

 badframe:
 	signal_fault(regs,frame,"32bit rt sigreturn");
 	return 0;
 }

 /*
  * Set up a signal frame.
  */

 static int
 ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc, struct _fpstate_ia32 __user *fpstate,
 		 struct pt_regs *regs, unsigned int mask)
 {
 	int tmp, err = 0;

 	tmp = 0;
 	__asm__("movl %%gs,%0" : "=r"(tmp): "0"(tmp));
 	err |= __put_user(tmp, (unsigned int __user *)&sc->gs);
 	__asm__("movl %%fs,%0" : "=r"(tmp): "0"(tmp));
 	err |= __put_user(tmp, (unsigned int __user *)&sc->fs);
 	__asm__("movl %%ds,%0" : "=r"(tmp): "0"(tmp));
 	err |= __put_user(tmp, (unsigned int __user *)&sc->ds);
 	__asm__("movl %%es,%0" : "=r"(tmp): "0"(tmp));
 	err |= __put_user(tmp, (unsigned int __user *)&sc->es);

 	err |= __put_user((u32)regs->rdi, &sc->edi);
 	err |= __put_user((u32)regs->rsi, &sc->esi);
 	err |= __put_user((u32)regs->rbp, &sc->ebp);
 	err |= __put_user((u32)regs->rsp, &sc->esp);
 	err |= __put_user((u32)regs->rbx, &sc->ebx);
 	err |= __put_user((u32)regs->rdx, &sc->edx);
 	err |= __put_user((u32)regs->rcx, &sc->ecx);
 	err |= __put_user((u32)regs->rax, &sc->eax);
 	err |= __put_user((u32)regs->cs, &sc->cs);
 	err |= __put_user((u32)regs->ss, &sc->ss);
 	err |= __put_user(current->thread.trap_no, &sc->trapno);
 	err |= __put_user(current->thread.error_code, &sc->err);
 	err |= __put_user((u32)regs->rip, &sc->eip);
 	err |= __put_user((u32)regs->eflags, &sc->eflags);
 	err |= __put_user((u32)regs->rsp, &sc->esp_at_signal);

 	tmp = save_i387_ia32(current, fpstate, regs, 0);
 	if (tmp < 0)
 		err = -EFAULT;
 	else {
 		clear_used_math();
 		stts();
 		err |= __put_user(ptr_to_compat(tmp ? fpstate : NULL),
 					&sc->fpstate);
 	}

 	/* non-iBCS2 extensions.. */
 	err |= __put_user(mask, &sc->oldmask);
 	err |= __put_user(current->thread.cr2, &sc->cr2);

 	return err;
 }

 /*
  * Determine which stack to use..
  */
 static void __user *
 get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
 {
 	unsigned long rsp;

 	/* Default to using normal stack */
 	rsp = regs->rsp;

 	/* This is the X/Open sanctioned signal stack switching.  */
 	if (ka->sa.sa_flags & SA_ONSTACK) {
 		if (sas_ss_flags(rsp) == 0)
 			rsp = current->sas_ss_sp + current->sas_ss_size;
 	}

 	/* This is the legacy signal stack switching. */
 	else if ((regs->ss & 0xffff) != __USER_DS &&
 		!(ka->sa.sa_flags & SA_RESTORER) &&
 		 ka->sa.sa_restorer) {
 		rsp = (unsigned long) ka->sa.sa_restorer;
 	}

 	rsp -= frame_size;
 	/* Align the stack pointer according to the i386 ABI,
 	 * i.e. so that on function entry ((sp + 4) & 15) == 0. */
 	rsp = ((rsp + 4) & -16ul) - 4;
 	return (void __user *) rsp;
 }

 int ia32_setup_frame(int sig, struct k_sigaction *ka,
 		     compat_sigset_t *set, struct pt_regs * regs)
 {
 	struct sigframe __user *frame;
 	int err = 0;

 	frame = get_sigframe(ka, regs, sizeof(*frame));

 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		goto give_sigsegv;

 	err |= __put_user(sig, &frame->sig);
 	if (err)
 		goto give_sigsegv;

 	err |= ia32_setup_sigcontext(&frame->sc, &frame->fpstate, regs,
 					set->sig[0]);
 	if (err)
 		goto give_sigsegv;

 	if (_COMPAT_NSIG_WORDS > 1) {
 		err |= __copy_to_user(frame->extramask, &set->sig[1],
 				      sizeof(frame->extramask));
 	}
 	if (err)
 		goto give_sigsegv;

 	/* Return stub is in 32bit vsyscall page */
 	{
 		void __user *restorer = VSYSCALL32_SIGRETURN;
 		if (ka->sa.sa_flags & SA_RESTORER)
 			restorer = ka->sa.sa_restorer;
 		err |= __put_user(ptr_to_compat(restorer), &frame->pretcode);
 	}
 	/* These are actually not used anymore, but left because some
 	   gdb versions depend on them as a marker. */
 	{
 		/* copy_to_user optimizes that into a single 8 byte store */
 		static const struct {
 			u16 poplmovl;
 			u32 val;
 			u16 int80;
 			u16 pad;
 		} __attribute__((packed)) code = {
 			0xb858,		 /* popl %eax ; movl $...,%eax */
 			__NR_ia32_sigreturn,
 			0x80cd,		/* int $0x80 */
 			0,
 		};
 		err |= __copy_to_user(frame->retcode, &code, 8);
 	}
 	if (err)
 		goto give_sigsegv;

 	/* Set up registers for signal handler */
 	regs->rsp = (unsigned long) frame;
 	regs->rip = (unsigned long) ka->sa.sa_handler;

 	/* Make -mregparm=3 work */
 	regs->rax = sig;
 	regs->rdx = 0;
 	regs->rcx = 0;

 	asm volatile("movl %0,%%ds" :: "r" (__USER32_DS));
 	asm volatile("movl %0,%%es" :: "r" (__USER32_DS));

 	regs->cs = __USER32_CS;
 	regs->ss = __USER32_DS;

 	set_fs(USER_DS);
 	regs->eflags &= ~TF_MASK;
 	if (test_thread_flag(TIF_SINGLESTEP))
 		ptrace_notify(SIGTRAP);

 #if DEBUG_SIG
 	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
 		current->comm, current->pid, frame, regs->rip, frame->pretcode);
 #endif

 	return 0;

 give_sigsegv:
 	force_sigsegv(sig, current);
 	return -EFAULT;
 }

 int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 			compat_sigset_t *set, struct pt_regs * regs)
 {
 	struct rt_sigframe __user *frame;
 	int err = 0;

 	frame = get_sigframe(ka, regs, sizeof(*frame));

 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		goto give_sigsegv;

 	{
 		struct exec_domain *ed = current_thread_info()->exec_domain;
 		err |= __put_user((ed
 		    	   && ed->signal_invmap
 		    	   && sig < 32
 		    	   ? ed->signal_invmap[sig]
 			   : sig),
 			  &frame->sig);
 	}
 	err |= __put_user(ptr_to_compat(&frame->info), &frame->pinfo);
 	err |= __put_user(ptr_to_compat(&frame->uc), &frame->puc);
 	err |= copy_siginfo_to_user32(&frame->info, info);
 	if (err)
 		goto give_sigsegv;

 	/* Create the ucontext.  */
 	err |= __put_user(0, &frame->uc.uc_flags);
 	err |= __put_user(0, &frame->uc.uc_link);
 	err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
 	err |= __put_user(sas_ss_flags(regs->rsp),
 			  &frame->uc.uc_stack.ss_flags);
 	err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
 	err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
 			        regs, set->sig[0]);
 	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
 	if (err)
 		goto give_sigsegv;


 	{
 		void __user *restorer = VSYSCALL32_RTSIGRETURN;
 		if (ka->sa.sa_flags & SA_RESTORER)
 			restorer = ka->sa.sa_restorer;
 		err |= __put_user(ptr_to_compat(restorer), &frame->pretcode);
 	}

 	/* This is movl $,%eax ; int $0x80 */
 	/* Not actually used anymore, but left because some gdb versions
 	   need it. */
 	{
 		/* __copy_to_user optimizes that into a single 8 byte store */
 		static const struct {
 			u8 movl;
 			u32 val;
 			u16 int80;
 			u16 pad;
 			u8  pad2;
 		} __attribute__((packed)) code = {
 			0xb8,
 			__NR_ia32_rt_sigreturn,
 			0x80cd,
 			0,
 		};
 		err |= __copy_to_user(frame->retcode, &code, 8);
 	}
 	if (err)
 		goto give_sigsegv;

 	/* Set up registers for signal handler */
 	regs->rsp = (unsigned long) frame;
 	regs->rip = (unsigned long) ka->sa.sa_handler;

 	/* Make -mregparm=3 work */
 	regs->rax = sig;
 	regs->rdx = (unsigned long) &frame->info;
 	regs->rcx = (unsigned long) &frame->uc;

 	/* Make -mregparm=3 work */
 	regs->rax = sig;
 	regs->rdx = (unsigned long) &frame->info;
 	regs->rcx = (unsigned long) &frame->uc;

 	asm volatile("movl %0,%%ds" :: "r" (__USER32_DS));
 	asm volatile("movl %0,%%es" :: "r" (__USER32_DS));

 	regs->cs = __USER32_CS;
 	regs->ss = __USER32_DS;

 	set_fs(USER_DS);
 	regs->eflags &= ~TF_MASK;
 	if (test_thread_flag(TIF_SINGLESTEP))
 		ptrace_notify(SIGTRAP);

 #if DEBUG_SIG
 	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
 		current->comm, current->pid, frame, regs->rip, frame->pretcode);
 #endif

 	return 0;

 give_sigsegv:
 	force_sigsegv(sig, current);
 	return -EFAULT;
 }
	/*
	* linux/arch/x86_64/ia32/ia32_signal.c
	*
	* Copyright (C) 1991, 1992 Linus Torvalds
	*
	* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
	* 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes
	* 2000-12-* x86-64 compatibility mode signal handling by Andi Kleen
	*/

	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/smp.h>
	#include <linux/smp_lock.h>
	#include <linux/kernel.h>
	#include <linux/signal.h>
	#include <linux/errno.h>
	#include <linux/wait.h>
	#include <linux/ptrace.h>
	#include <linux/unistd.h>
	#include <linux/stddef.h>
	#include <linux/personality.h>
	#include <linux/compat.h>
	#include <asm/ucontext.h>
	#include <asm/uaccess.h>
	#include <asm/i387.h>
	#include <asm/ia32.h>
	#include <asm/ptrace.h>
	#include <asm/ia32_unistd.h>
	#include <asm/user32.h>
	#include <asm/sigcontext32.h>
	#include <asm/fpu32.h>
	#include <asm/proto.h>
	#include <asm/vsyscall32.h>

	#define DEBUG_SIG 0

	#define _BLOCKABLE (~(sigmask(SIGKILL) \| sigmask(SIGSTOP)))

	asmlinkage int do_signal(struct pt_regs regs, sigset_t oldset);
	void signal_fault(struct pt_regs regs, void __user frame, char *where);

	int copy_siginfo_to_user32(compat_siginfo_t __user to, siginfo_t from)
	{
	int err;
	if (!access_ok (VERIFY_WRITE, to, sizeof(compat_siginfo_t)))
	return -EFAULT;

	/* If you change siginfo_t structure, please make sure that
	this code is fixed accordingly.
	It should never copy any pad contained in the structure
	to avoid security leaks, but must copy the generic
	3 ints plus the relevant union member. */
	err = __put_user(from->si_signo, &to->si_signo);
	err \|= __put_user(from->si_errno, &to->si_errno);
	err \|= __put_user((short)from->si_code, &to->si_code);

	if (from->si_code < 0) {
	err \|= __put_user(from->si_pid, &to->si_pid);
	err \|= __put_user(from->si_uid, &to->si_uid);
	err \|= __put_user(ptr_to_compat(from->si_ptr), &to->si_ptr);
	} else {
	/* First 32bits of unions are always present:
	* si_pid === si_band === si_tid === si_addr(LS half) */
	err \|= __put_user(from->_sifields._pad[0], &to->_sifields._pad[0]);
	switch (from->si_code >> 16) {
	case __SI_FAULT >> 16:
	break;
	case __SI_CHLD >> 16:
	err \|= __put_user(from->si_utime, &to->si_utime);
	err \|= __put_user(from->si_stime, &to->si_stime);
	err \|= __put_user(from->si_status, &to->si_status);
	/* FALL THROUGH */
	default:
	case __SI_KILL >> 16:
	err \|= __put_user(from->si_uid, &to->si_uid);
	break;
	case __SI_POLL >> 16:
	err \|= __put_user(from->si_fd, &to->si_fd);
	break;
	case __SI_TIMER >> 16:
	err \|= __put_user(from->si_overrun, &to->si_overrun);
	err \|= __put_user(ptr_to_compat(from->si_ptr),
	&to->si_ptr);
	break;
	case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
	case __SI_MESGQ >> 16:
	err \|= __put_user(from->si_uid, &to->si_uid);
	err \|= __put_user(from->si_int, &to->si_int);
	break;
	}
	}
	return err;
	}

	int copy_siginfo_from_user32(siginfo_t to, compat_siginfo_t __user from)
	{
	int err;
	u32 ptr32;
	if (!access_ok (VERIFY_READ, from, sizeof(compat_siginfo_t)))
	return -EFAULT;

	err = __get_user(to->si_signo, &from->si_signo);
	err \|= __get_user(to->si_errno, &from->si_errno);
	err \|= __get_user(to->si_code, &from->si_code);

	err \|= __get_user(to->si_pid, &from->si_pid);
	err \|= __get_user(to->si_uid, &from->si_uid);
	err \|= __get_user(ptr32, &from->si_ptr);
	to->si_ptr = compat_ptr(ptr32);

	return err;
	}

	asmlinkage long
	sys32_sigsuspend(int history0, int history1, old_sigset_t mask)
	{
	mask &= _BLOCKABLE;
	spin_lock_irq(&current->sighand->siglock);
	current->saved_sigmask = current->blocked;
	siginitset(&current->blocked, mask);
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	current->state = TASK_INTERRUPTIBLE;
	schedule();
	set_thread_flag(TIF_RESTORE_SIGMASK);
	return -ERESTARTNOHAND;
	}

	asmlinkage long
	sys32_sigaltstack(const stack_ia32_t __user *uss_ptr,
	stack_ia32_t __user *uoss_ptr,
	struct pt_regs *regs)
	{
	stack_t uss,uoss;
	int ret;
	mm_segment_t seg;
	if (uss_ptr) {
	u32 ptr;
	memset(&uss,0,sizeof(stack_t));
	if (!access_ok(VERIFY_READ,uss_ptr,sizeof(stack_ia32_t)) \|\|
	__get_user(ptr, &uss_ptr->ss_sp) \|\|
	__get_user(uss.ss_flags, &uss_ptr->ss_flags) \|\|
	__get_user(uss.ss_size, &uss_ptr->ss_size))
	return -EFAULT;
	uss.ss_sp = compat_ptr(ptr);
	}
	seg = get_fs();
	set_fs(KERNEL_DS);
	ret = do_sigaltstack(uss_ptr ? &uss : NULL, &uoss, regs->rsp);
	set_fs(seg);
	if (ret >= 0 && uoss_ptr) {
	if (!access_ok(VERIFY_WRITE,uoss_ptr,sizeof(stack_ia32_t)) \|\|
	__put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) \|\|
	__put_user(uoss.ss_flags, &uoss_ptr->ss_flags) \|\|
	__put_user(uoss.ss_size, &uoss_ptr->ss_size))
	ret = -EFAULT;
	}
	return ret;
	}

	/*
	* Do a signal return; undo the signal stack.
	*/

	struct sigframe
	{
	u32 pretcode;
	int sig;
	struct sigcontext_ia32 sc;
	struct _fpstate_ia32 fpstate;
	unsigned int extramask[_COMPAT_NSIG_WORDS-1];
	char retcode[8];
	};

	struct rt_sigframe
	{
	u32 pretcode;
	int sig;
	u32 pinfo;
	u32 puc;
	compat_siginfo_t info;
	struct ucontext_ia32 uc;
	struct _fpstate_ia32 fpstate;
	char retcode[8];
	};

	static int
	ia32_restore_sigcontext(struct pt_regs regs, struct sigcontext_ia32 __user sc, unsigned int *peax)
	{
	unsigned int err = 0;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	#if DEBUG_SIG
	printk("SIG restore_sigcontext: sc=%p err(%x) eip(%x) cs(%x) flg(%x)\n",
	sc, sc->err, sc->eip, sc->cs, sc->eflags);
	#endif
	#define COPY(x) { \
	unsigned int reg; \
	err \|= __get_user(reg, &sc->e ##x); \
	regs->r ## x = reg; \
	}

	#define RELOAD_SEG(seg,mask) \
	{ unsigned int cur; \
	unsigned short pre; \
	err \|= __get_user(pre, &sc->seg); \
	asm volatile("movl %%" #seg ",%0" : "=r" (cur)); \
	pre \|= mask; \
	if (pre != cur) loadsegment(seg,pre); }

	/* Reload fs and gs if they have changed in the signal handler.
	This does not handle long fs/gs base changes in the handler, but
	does not clobber them at least in the normal case. */

	{
	unsigned gs, oldgs;
	err \|= __get_user(gs, &sc->gs);
	gs \|= 3;
	asm("movl %%gs,%0" : "=r" (oldgs));
	if (gs != oldgs)
	load_gs_index(gs);
	}
	RELOAD_SEG(fs,3);
	RELOAD_SEG(ds,3);
	RELOAD_SEG(es,3);

	COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
	COPY(dx); COPY(cx); COPY(ip);
	/* Don't touch extended registers */

	err \|= __get_user(regs->cs, &sc->cs);
	regs->cs \|= 3;
	err \|= __get_user(regs->ss, &sc->ss);
	regs->ss \|= 3;

	{
	unsigned int tmpflags;
	err \|= __get_user(tmpflags, &sc->eflags);
	regs->eflags = (regs->eflags & ~0x40DD5) \| (tmpflags & 0x40DD5);
	regs->orig_rax = -1; /* disable syscall checks */
	}

	{
	u32 tmp;
	struct _fpstate_ia32 __user * buf;
	err \|= __get_user(tmp, &sc->fpstate);
	buf = compat_ptr(tmp);
	if (buf) {
	if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
	goto badframe;
	err \|= restore_i387_ia32(current, buf, 0);
	} else {
	struct task_struct *me = current;
	if (used_math()) {
	clear_fpu(me);
	clear_used_math();
	}
	}
	}

	{
	u32 tmp;
	err \|= __get_user(tmp, &sc->eax);
	*peax = tmp;
	}
	return err;

	badframe:
	return 1;
	}

	asmlinkage long sys32_sigreturn(struct pt_regs *regs)
	{
	struct sigframe __user frame = (struct sigframe __user )(regs->rsp-8);
	sigset_t set;
	unsigned int eax;

	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	goto badframe;
	if (__get_user(set.sig[0], &frame->sc.oldmask)
	\|\| (_COMPAT_NSIG_WORDS > 1
	&& __copy_from_user((((char *) &set.sig) + 4), &frame->extramask,
	sizeof(frame->extramask))))
	goto badframe;

	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	if (ia32_restore_sigcontext(regs, &frame->sc, &eax))
	goto badframe;
	return eax;

	badframe:
	signal_fault(regs, frame, "32bit sigreturn");
	return 0;
	}

	asmlinkage long sys32_rt_sigreturn(struct pt_regs *regs)
	{
	struct rt_sigframe __user *frame;
	sigset_t set;
	unsigned int eax;
	struct pt_regs tregs;

	frame = (struct rt_sigframe __user *)(regs->rsp - 4);

	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	goto badframe;
	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
	goto badframe;

	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	if (ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax))
	goto badframe;

	tregs = *regs;
	if (sys32_sigaltstack(&frame->uc.uc_stack, NULL, &tregs) == -EFAULT)
	goto badframe;

	return eax;

	badframe:
	signal_fault(regs,frame,"32bit rt sigreturn");
	return 0;
	}

	/*
	* Set up a signal frame.
	*/

	static int
	ia32_setup_sigcontext(struct sigcontext_ia32 __user sc, struct _fpstate_ia32 __user fpstate,
	struct pt_regs *regs, unsigned int mask)
	{
	int tmp, err = 0;

	tmp = 0;
	__asm__("movl %%gs,%0" : "=r"(tmp): "0"(tmp));
	err \|= __put_user(tmp, (unsigned int __user *)&sc->gs);
	__asm__("movl %%fs,%0" : "=r"(tmp): "0"(tmp));
	err \|= __put_user(tmp, (unsigned int __user *)&sc->fs);
	__asm__("movl %%ds,%0" : "=r"(tmp): "0"(tmp));
	err \|= __put_user(tmp, (unsigned int __user *)&sc->ds);
	__asm__("movl %%es,%0" : "=r"(tmp): "0"(tmp));
	err \|= __put_user(tmp, (unsigned int __user *)&sc->es);

	err \|= __put_user((u32)regs->rdi, &sc->edi);
	err \|= __put_user((u32)regs->rsi, &sc->esi);
	err \|= __put_user((u32)regs->rbp, &sc->ebp);
	err \|= __put_user((u32)regs->rsp, &sc->esp);
	err \|= __put_user((u32)regs->rbx, &sc->ebx);
	err \|= __put_user((u32)regs->rdx, &sc->edx);
	err \|= __put_user((u32)regs->rcx, &sc->ecx);
	err \|= __put_user((u32)regs->rax, &sc->eax);
	err \|= __put_user((u32)regs->cs, &sc->cs);
	err \|= __put_user((u32)regs->ss, &sc->ss);
	err \|= __put_user(current->thread.trap_no, &sc->trapno);
	err \|= __put_user(current->thread.error_code, &sc->err);
	err \|= __put_user((u32)regs->rip, &sc->eip);
	err \|= __put_user((u32)regs->eflags, &sc->eflags);
	err \|= __put_user((u32)regs->rsp, &sc->esp_at_signal);

	tmp = save_i387_ia32(current, fpstate, regs, 0);
	if (tmp < 0)
	err = -EFAULT;
	else {
	clear_used_math();
	stts();
	err \|= __put_user(ptr_to_compat(tmp ? fpstate : NULL),
	&sc->fpstate);
	}

	/* non-iBCS2 extensions.. */
	err \|= __put_user(mask, &sc->oldmask);
	err \|= __put_user(current->thread.cr2, &sc->cr2);

	return err;
	}

	/*
	* Determine which stack to use..
	*/
	static void __user *
	get_sigframe(struct k_sigaction ka, struct pt_regs regs, size_t frame_size)
	{
	unsigned long rsp;

	/* Default to using normal stack */
	rsp = regs->rsp;

	/* This is the X/Open sanctioned signal stack switching. */
	if (ka->sa.sa_flags & SA_ONSTACK) {
	if (sas_ss_flags(rsp) == 0)
	rsp = current->sas_ss_sp + current->sas_ss_size;
	}

	/* This is the legacy signal stack switching. */
	else if ((regs->ss & 0xffff) != __USER_DS &&
	!(ka->sa.sa_flags & SA_RESTORER) &&
	ka->sa.sa_restorer) {
	rsp = (unsigned long) ka->sa.sa_restorer;
	}

	rsp -= frame_size;
	/* Align the stack pointer according to the i386 ABI,
	* i.e. so that on function entry ((sp + 4) & 15) == 0. */
	rsp = ((rsp + 4) & -16ul) - 4;
	return (void __user *) rsp;
	}

	int ia32_setup_frame(int sig, struct k_sigaction *ka,
	compat_sigset_t set, struct pt_regs regs)
	{
	struct sigframe __user *frame;
	int err = 0;

	frame = get_sigframe(ka, regs, sizeof(*frame));

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	goto give_sigsegv;

	err \|= __put_user(sig, &frame->sig);
	if (err)
	goto give_sigsegv;

	err \|= ia32_setup_sigcontext(&frame->sc, &frame->fpstate, regs,
	set->sig[0]);
	if (err)
	goto give_sigsegv;

	if (_COMPAT_NSIG_WORDS > 1) {
	err \|= __copy_to_user(frame->extramask, &set->sig[1],
	sizeof(frame->extramask));
	}
	if (err)
	goto give_sigsegv;

	/* Return stub is in 32bit vsyscall page */
	{
	void __user *restorer = VSYSCALL32_SIGRETURN;
	if (ka->sa.sa_flags & SA_RESTORER)
	restorer = ka->sa.sa_restorer;
	err \|= __put_user(ptr_to_compat(restorer), &frame->pretcode);
	}
	/* These are actually not used anymore, but left because some
	gdb versions depend on them as a marker. */
	{
	/* copy_to_user optimizes that into a single 8 byte store */
	static const struct {
	u16 poplmovl;
	u32 val;
	u16 int80;
	u16 pad;
	} __attribute__((packed)) code = {
	0xb858, /* popl %eax ; movl $...,%eax */
	__NR_ia32_sigreturn,
	0x80cd, /* int $0x80 */
	0,
	};
	err \|= __copy_to_user(frame->retcode, &code, 8);
	}
	if (err)
	goto give_sigsegv;

	/* Set up registers for signal handler */
	regs->rsp = (unsigned long) frame;
	regs->rip = (unsigned long) ka->sa.sa_handler;

	/* Make -mregparm=3 work */
	regs->rax = sig;
	regs->rdx = 0;
	regs->rcx = 0;

	asm volatile("movl %0,%%ds" :: "r" (__USER32_DS));
	asm volatile("movl %0,%%es" :: "r" (__USER32_DS));

	regs->cs = __USER32_CS;
	regs->ss = __USER32_DS;

	set_fs(USER_DS);
	regs->eflags &= ~TF_MASK;
	if (test_thread_flag(TIF_SINGLESTEP))
	ptrace_notify(SIGTRAP);

	#if DEBUG_SIG
	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
	current->comm, current->pid, frame, regs->rip, frame->pretcode);
	#endif

	return 0;

	give_sigsegv:
	force_sigsegv(sig, current);
	return -EFAULT;
	}

	int ia32_setup_rt_frame(int sig, struct k_sigaction ka, siginfo_t info,
	compat_sigset_t set, struct pt_regs regs)
	{
	struct rt_sigframe __user *frame;
	int err = 0;

	frame = get_sigframe(ka, regs, sizeof(*frame));

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	goto give_sigsegv;

	{
	struct exec_domain *ed = current_thread_info()->exec_domain;
	err \|= __put_user((ed
	&& ed->signal_invmap
	&& sig < 32
	? ed->signal_invmap[sig]
	: sig),
	&frame->sig);
	}
	err \|= __put_user(ptr_to_compat(&frame->info), &frame->pinfo);
	err \|= __put_user(ptr_to_compat(&frame->uc), &frame->puc);
	err \|= copy_siginfo_to_user32(&frame->info, info);
	if (err)
	goto give_sigsegv;

	/* Create the ucontext. */
	err \|= __put_user(0, &frame->uc.uc_flags);
	err \|= __put_user(0, &frame->uc.uc_link);
	err \|= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
	err \|= __put_user(sas_ss_flags(regs->rsp),
	&frame->uc.uc_stack.ss_flags);
	err \|= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
	err \|= ia32_setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
	regs, set->sig[0]);
	err \|= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
	if (err)
	goto give_sigsegv;


	{
	void __user *restorer = VSYSCALL32_RTSIGRETURN;
	if (ka->sa.sa_flags & SA_RESTORER)
	restorer = ka->sa.sa_restorer;
	err \|= __put_user(ptr_to_compat(restorer), &frame->pretcode);
	}

	/* This is movl $,%eax ; int $0x80 */
	/* Not actually used anymore, but left because some gdb versions
	need it. */
	{
	/* __copy_to_user optimizes that into a single 8 byte store */
	static const struct {
	u8 movl;
	u32 val;
	u16 int80;
	u16 pad;
	u8 pad2;
	} __attribute__((packed)) code = {
	0xb8,
	__NR_ia32_rt_sigreturn,
	0x80cd,
	0,
	};
	err \|= __copy_to_user(frame->retcode, &code, 8);
	}
	if (err)
	goto give_sigsegv;

	/* Set up registers for signal handler */
	regs->rsp = (unsigned long) frame;
	regs->rip = (unsigned long) ka->sa.sa_handler;

	/* Make -mregparm=3 work */
	regs->rax = sig;
	regs->rdx = (unsigned long) &frame->info;
	regs->rcx = (unsigned long) &frame->uc;

	/* Make -mregparm=3 work */
	regs->rax = sig;
	regs->rdx = (unsigned long) &frame->info;
	regs->rcx = (unsigned long) &frame->uc;

	asm volatile("movl %0,%%ds" :: "r" (__USER32_DS));
	asm volatile("movl %0,%%es" :: "r" (__USER32_DS));

	regs->cs = __USER32_CS;
	regs->ss = __USER32_DS;

	set_fs(USER_DS);
	regs->eflags &= ~TF_MASK;
	if (test_thread_flag(TIF_SINGLESTEP))
	ptrace_notify(SIGTRAP);

	#if DEBUG_SIG
	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
	current->comm, current->pid, frame, regs->rip, frame->pretcode);
	#endif

	return 0;

	give_sigsegv:
	force_sigsegv(sig, current);
	return -EFAULT;
	}