[linux-block.git] / arch / s390 / kernel / compat_signal.c

// SPDX-License-Identifier: GPL-2.0
/*
 *    Copyright IBM Corp. 2000, 2006
 *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
 *               Gerhard Tonn (ton@de.ibm.com)                  
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  1997-11-28  Modified for POSIX.1b signals by Richard Henderson
 */

#include <linux/compat.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <linux/mm.h>
#include <linux/smp.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/tty.h>
#include <linux/personality.h>
#include <linux/binfmts.h>
#include <asm/ucontext.h>
#include <linux/uaccess.h>
#include <asm/lowcore.h>
#include <asm/switch_to.h>
#include <asm/vdso.h>
#include "compat_linux.h"
#include "compat_ptrace.h"
#include "entry.h"

typedef struct 
{
	__u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
	struct sigcontext32 sc;
	_sigregs32 sregs;
	int signo;
	_sigregs_ext32 sregs_ext;
	__u16 svc_insn;		/* Offset of svc_insn is NOT fixed! */
} sigframe32;

typedef struct 
{
	__u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
	__u16 svc_insn;
	compat_siginfo_t info;
	struct ucontext32 uc;
} rt_sigframe32;

/* Store registers needed to create the signal frame */
static void store_sigregs(void)
{
	save_access_regs(current->thread.acrs);
	save_fpu_regs();
}

/* Load registers after signal return */
static void load_sigregs(void)
{
	restore_access_regs(current->thread.acrs);
}

static int save_sigregs32(struct pt_regs *regs, _sigregs32 __user *sregs)
{
	_sigregs32 user_sregs;
	int i;

	user_sregs.regs.psw.mask = (__u32)(regs->psw.mask >> 32);
	user_sregs.regs.psw.mask &= PSW32_MASK_USER | PSW32_MASK_RI;
	user_sregs.regs.psw.mask |= PSW32_USER_BITS;
	user_sregs.regs.psw.addr = (__u32) regs->psw.addr |
		(__u32)(regs->psw.mask & PSW_MASK_BA);
	for (i = 0; i < NUM_GPRS; i++)
		user_sregs.regs.gprs[i] = (__u32) regs->gprs[i];
	memcpy(&user_sregs.regs.acrs, current->thread.acrs,
	       sizeof(user_sregs.regs.acrs));
	fpregs_store((_s390_fp_regs *) &user_sregs.fpregs, &current->thread.fpu);
	if (__copy_to_user(sregs, &user_sregs, sizeof(_sigregs32)))
		return -EFAULT;
	return 0;
}

static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs)
{
	_sigregs32 user_sregs;
	int i;

	/* Always make any pending restarted system call return -EINTR */
	current->restart_block.fn = do_no_restart_syscall;

	if (__copy_from_user(&user_sregs, &sregs->regs, sizeof(user_sregs)))
		return -EFAULT;

	if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW32_MASK_RI))
		return -EINVAL;

	/* Test the floating-point-control word. */
	if (test_fp_ctl(user_sregs.fpregs.fpc))
		return -EINVAL;

	/* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */
	regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER | PSW_MASK_RI)) |
		(__u64)(user_sregs.regs.psw.mask & PSW32_MASK_USER) << 32 |
		(__u64)(user_sregs.regs.psw.mask & PSW32_MASK_RI) << 32 |
		(__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_AMODE);
	/* Check for invalid user address space control. */
	if ((regs->psw.mask & PSW_MASK_ASC) == PSW_ASC_HOME)
		regs->psw.mask = PSW_ASC_PRIMARY |
			(regs->psw.mask & ~PSW_MASK_ASC);
	regs->psw.addr = (__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_INSN);
	for (i = 0; i < NUM_GPRS; i++)
		regs->gprs[i] = (__u64) user_sregs.regs.gprs[i];
	memcpy(&current->thread.acrs, &user_sregs.regs.acrs,
	       sizeof(current->thread.acrs));
	fpregs_load((_s390_fp_regs *) &user_sregs.fpregs, &current->thread.fpu);

	clear_pt_regs_flag(regs, PIF_SYSCALL); /* No longer in a system call */
	return 0;
}

static int save_sigregs_ext32(struct pt_regs *regs,
			      _sigregs_ext32 __user *sregs_ext)
{
	__u32 gprs_high[NUM_GPRS];
	__u64 vxrs[__NUM_VXRS_LOW];
	int i;

	/* Save high gprs to signal stack */
	for (i = 0; i < NUM_GPRS; i++)
		gprs_high[i] = regs->gprs[i] >> 32;
	if (__copy_to_user(&sregs_ext->gprs_high, &gprs_high,
			   sizeof(sregs_ext->gprs_high)))
		return -EFAULT;

	/* Save vector registers to signal stack */
	if (MACHINE_HAS_VX) {
		for (i = 0; i < __NUM_VXRS_LOW; i++)
			vxrs[i] = current->thread.fpu.vxrs[i].low;
		if (__copy_to_user(&sregs_ext->vxrs_low, vxrs,
				   sizeof(sregs_ext->vxrs_low)) ||
		    __copy_to_user(&sregs_ext->vxrs_high,
				   current->thread.fpu.vxrs + __NUM_VXRS_LOW,
				   sizeof(sregs_ext->vxrs_high)))
			return -EFAULT;
	}
	return 0;
}

static int restore_sigregs_ext32(struct pt_regs *regs,
				 _sigregs_ext32 __user *sregs_ext)
{
	__u32 gprs_high[NUM_GPRS];
	__u64 vxrs[__NUM_VXRS_LOW];
	int i;

	/* Restore high gprs from signal stack */
	if (__copy_from_user(&gprs_high, &sregs_ext->gprs_high,
			     sizeof(sregs_ext->gprs_high)))
		return -EFAULT;
	for (i = 0; i < NUM_GPRS; i++)
		*(__u32 *)&regs->gprs[i] = gprs_high[i];

	/* Restore vector registers from signal stack */
	if (MACHINE_HAS_VX) {
		if (__copy_from_user(vxrs, &sregs_ext->vxrs_low,
				     sizeof(sregs_ext->vxrs_low)) ||
		    __copy_from_user(current->thread.fpu.vxrs + __NUM_VXRS_LOW,
				     &sregs_ext->vxrs_high,
				     sizeof(sregs_ext->vxrs_high)))
			return -EFAULT;
		for (i = 0; i < __NUM_VXRS_LOW; i++)
			current->thread.fpu.vxrs[i].low = vxrs[i];
	}
	return 0;
}

COMPAT_SYSCALL_DEFINE0(sigreturn)
{
	struct pt_regs *regs = task_pt_regs(current);
	sigframe32 __user *frame = (sigframe32 __user *)regs->gprs[15];
	sigset_t set;

	if (get_compat_sigset(&set, (compat_sigset_t __user *)frame->sc.oldmask))
		goto badframe;
	set_current_blocked(&set);
	save_fpu_regs();
	if (restore_sigregs32(regs, &frame->sregs))
		goto badframe;
	if (restore_sigregs_ext32(regs, &frame->sregs_ext))
		goto badframe;
	load_sigregs();
	return regs->gprs[2];
badframe:
	force_sig(SIGSEGV);
	return 0;
}

COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
{
	struct pt_regs *regs = task_pt_regs(current);
	rt_sigframe32 __user *frame = (rt_sigframe32 __user *)regs->gprs[15];
	sigset_t set;

	if (get_compat_sigset(&set, &frame->uc.uc_sigmask))
		goto badframe;
	set_current_blocked(&set);
	if (compat_restore_altstack(&frame->uc.uc_stack))
		goto badframe;
	save_fpu_regs();
	if (restore_sigregs32(regs, &frame->uc.uc_mcontext))
		goto badframe;
	if (restore_sigregs_ext32(regs, &frame->uc.uc_mcontext_ext))
		goto badframe;
	load_sigregs();
	return regs->gprs[2];
badframe:
	force_sig(SIGSEGV);
	return 0;
}	

/*
 * Set up a signal frame.
 */


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

	/* Default to using normal stack */
	sp = (unsigned long) A(regs->gprs[15]);

	/* Overflow on alternate signal stack gives SIGSEGV. */
	if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL))
		return (void __user *) -1UL;

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

	return (void __user *)((sp - frame_size) & -8ul);
}

static int setup_frame32(struct ksignal *ksig, sigset_t *set,
			 struct pt_regs *regs)
{
	int sig = ksig->sig;
	sigframe32 __user *frame;
	unsigned long restorer;
	size_t frame_size;

	/*
	 * gprs_high are always present for 31-bit compat tasks.
	 * The space for vector registers is only allocated if
	 * the machine supports it
	 */
	frame_size = sizeof(*frame) - sizeof(frame->sregs_ext.__reserved);
	if (!MACHINE_HAS_VX)
		frame_size -= sizeof(frame->sregs_ext.vxrs_low) +
			      sizeof(frame->sregs_ext.vxrs_high);
	frame = get_sigframe(&ksig->ka, regs, frame_size);
	if (frame == (void __user *) -1UL)
		return -EFAULT;

	/* Set up backchain. */
	if (__put_user(regs->gprs[15], (unsigned int __user *) frame))
		return -EFAULT;

	/* Create struct sigcontext32 on the signal stack */
	if (put_compat_sigset((compat_sigset_t __user *)frame->sc.oldmask,
			      set, sizeof(compat_sigset_t)))
		return -EFAULT;
	if (__put_user(ptr_to_compat(&frame->sregs), &frame->sc.sregs))
		return -EFAULT;

	/* Store registers needed to create the signal frame */
	store_sigregs();

	/* Create _sigregs32 on the signal stack */
	if (save_sigregs32(regs, &frame->sregs))
		return -EFAULT;

	/* Place signal number on stack to allow backtrace from handler.  */
	if (__put_user(regs->gprs[2], (int __force __user *) &frame->signo))
		return -EFAULT;

	/* Create _sigregs_ext32 on the signal stack */
	if (save_sigregs_ext32(regs, &frame->sregs_ext))
		return -EFAULT;

	/* Set up to return from userspace.  If provided, use a stub
	   already in userspace.  */
	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
		restorer = (unsigned long __force)
			ksig->ka.sa.sa_restorer | PSW32_ADDR_AMODE;
	} else {
		restorer = VDSO32_SYMBOL(current, sigreturn);
        }

	/* Set up registers for signal handler */
	regs->gprs[14] = restorer;
	regs->gprs[15] = (__force __u64) frame;
	/* Force 31 bit amode and default user address space control. */
	regs->psw.mask = PSW_MASK_BA |
		(PSW_USER_BITS & PSW_MASK_ASC) |
		(regs->psw.mask & ~PSW_MASK_ASC);
	regs->psw.addr = (__force __u64) ksig->ka.sa.sa_handler;

	regs->gprs[2] = sig;
	regs->gprs[3] = (__force __u64) &frame->sc;

	/* We forgot to include these in the sigcontext.
	   To avoid breaking binary compatibility, they are passed as args. */
	if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
	    sig == SIGTRAP || sig == SIGFPE) {
		/* set extra registers only for synchronous signals */
		regs->gprs[4] = regs->int_code & 127;
		regs->gprs[5] = regs->int_parm_long;
		regs->gprs[6] = current->thread.last_break;
	}

	return 0;
}

static int setup_rt_frame32(struct ksignal *ksig, sigset_t *set,
			    struct pt_regs *regs)
{
	rt_sigframe32 __user *frame;
	unsigned long restorer;
	size_t frame_size;
	u32 uc_flags;

	frame_size = sizeof(*frame) -
		     sizeof(frame->uc.uc_mcontext_ext.__reserved);
	/*
	 * gprs_high are always present for 31-bit compat tasks.
	 * The space for vector registers is only allocated if
	 * the machine supports it
	 */
	uc_flags = UC_GPRS_HIGH;
	if (MACHINE_HAS_VX) {
		uc_flags |= UC_VXRS;
	} else
		frame_size -= sizeof(frame->uc.uc_mcontext_ext.vxrs_low) +
			      sizeof(frame->uc.uc_mcontext_ext.vxrs_high);
	frame = get_sigframe(&ksig->ka, regs, frame_size);
	if (frame == (void __user *) -1UL)
		return -EFAULT;

	/* Set up backchain. */
	if (__put_user(regs->gprs[15], (unsigned int __force __user *) frame))
		return -EFAULT;

	/* Set up to return from userspace.  If provided, use a stub
	   already in userspace.  */
	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
		restorer = (unsigned long __force)
			ksig->ka.sa.sa_restorer | PSW32_ADDR_AMODE;
	} else {
		restorer = VDSO32_SYMBOL(current, rt_sigreturn);
	}

	/* Create siginfo on the signal stack */
	if (copy_siginfo_to_user32(&frame->info, &ksig->info))
		return -EFAULT;

	/* Store registers needed to create the signal frame */
	store_sigregs();

	/* Create ucontext on the signal stack. */
	if (__put_user(uc_flags, &frame->uc.uc_flags) ||
	    __put_user(0, &frame->uc.uc_link) ||
	    __compat_save_altstack(&frame->uc.uc_stack, regs->gprs[15]) ||
	    save_sigregs32(regs, &frame->uc.uc_mcontext) ||
	    put_compat_sigset(&frame->uc.uc_sigmask, set, sizeof(compat_sigset_t)) ||
	    save_sigregs_ext32(regs, &frame->uc.uc_mcontext_ext))
		return -EFAULT;

	/* Set up registers for signal handler */
	regs->gprs[14] = restorer;
	regs->gprs[15] = (__force __u64) frame;
	/* Force 31 bit amode and default user address space control. */
	regs->psw.mask = PSW_MASK_BA |
		(PSW_USER_BITS & PSW_MASK_ASC) |
		(regs->psw.mask & ~PSW_MASK_ASC);
	regs->psw.addr = (__u64 __force) ksig->ka.sa.sa_handler;

	regs->gprs[2] = ksig->sig;
	regs->gprs[3] = (__force __u64) &frame->info;
	regs->gprs[4] = (__force __u64) &frame->uc;
	regs->gprs[5] = current->thread.last_break;
	return 0;
}

/*
 * OK, we're invoking a handler
 */	

void handle_signal32(struct ksignal *ksig, sigset_t *oldset,
		     struct pt_regs *regs)
{
	int ret;

	/* Set up the stack frame */
	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
		ret = setup_rt_frame32(ksig, oldset, regs);
	else
		ret = setup_frame32(ksig, oldset, regs);

	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLE_STEP));
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4	2	/*
a53c8fab	3	* Copyright IBM Corp. 2000, 2006
1da177e4 LT	4	* Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
	5	* Gerhard Tonn (ton@de.ibm.com)
	6	*
	7	* Copyright (C) 1991, 1992 Linus Torvalds
	8	*
	9	* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
	10	*/
	11
1da177e4 LT	12	#include <linux/compat.h>
1da177e4 LT	13	#include <linux/sched.h>
68db0cf1	14	#include <linux/sched/task_stack.h>
1da177e4 LT	15	#include <linux/mm.h>
1da177e4 LT	16	#include <linux/smp.h>
1da177e4 LT	17	#include <linux/kernel.h>
	18	#include <linux/signal.h>
	19	#include <linux/errno.h>
	20	#include <linux/wait.h>
	21	#include <linux/ptrace.h>
	22	#include <linux/unistd.h>
	23	#include <linux/stddef.h>
	24	#include <linux/tty.h>
	25	#include <linux/personality.h>
	26	#include <linux/binfmts.h>
	27	#include <asm/ucontext.h>
7c0f6ba6	28	#include <linux/uaccess.h>
1da177e4	29	#include <asm/lowcore.h>
a0616cde	30	#include <asm/switch_to.h>
df29a744	31	#include <asm/vdso.h>
1da177e4 LT	32	#include "compat_linux.h"
1da177e4 LT	33	#include "compat_ptrace.h"
a806170e	34	#include "entry.h"
1da177e4	35
1da177e4 LT	36	typedef struct
	37	{
	38	__u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
	39	struct sigcontext32 sc;
	40	_sigregs32 sregs;
	41	int signo;
80703617 MS	42	_sigregs_ext32 sregs_ext;
80703617 MS	43	__u16 svc_insn; /* Offset of svc_insn is NOT fixed! */
1da177e4 LT	44	} sigframe32;
	45
	46	typedef struct
	47	{
	48	__u8 callee_used_stack[__SIGNAL_FRAMESIZE32];
80703617	49	__u16 svc_insn;
1da177e4 LT	50	compat_siginfo_t info;
	51	struct ucontext32 uc;
	52	} rt_sigframe32;
	53
80703617 MS	54	/* Store registers needed to create the signal frame */
	55	static void store_sigregs(void)
	56	{
80703617	57	save_access_regs(current->thread.acrs);
d0164ee2	58	save_fpu_regs();
80703617 MS	59	}
	60
	61	/* Load registers after signal return */
	62	static void load_sigregs(void)
	63	{
80703617	64	restore_access_regs(current->thread.acrs);
80703617 MS	65	}
80703617 MS	66
1da177e4 LT	67	static int save_sigregs32(struct pt_regs regs, _sigregs32 __user sregs)
1da177e4 LT	68	{
4725c860 MS	69	_sigregs32 user_sregs;
4725c860 MS	70	int i;
1da177e4	71
5ebf250d HC	72	user_sregs.regs.psw.mask = (__u32)(regs->psw.mask >> 32);
5ebf250d HC	73	user_sregs.regs.psw.mask &= PSW32_MASK_USER \| PSW32_MASK_RI;
f26946d7	74	user_sregs.regs.psw.mask \|= PSW32_USER_BITS;
4725c860	75	user_sregs.regs.psw.addr = (__u32) regs->psw.addr \|
d4e81b35	76	(__u32)(regs->psw.mask & PSW_MASK_BA);
1da177e4	77	for (i = 0; i < NUM_GPRS; i++)
4725c860	78	user_sregs.regs.gprs[i] = (__u32) regs->gprs[i];
4725c860 MS	79	memcpy(&user_sregs.regs.acrs, current->thread.acrs,
4725c860 MS	80	sizeof(user_sregs.regs.acrs));
904818e2	81	fpregs_store((_s390_fp_regs *) &user_sregs.fpregs, &current->thread.fpu);
4725c860	82	if (__copy_to_user(sregs, &user_sregs, sizeof(_sigregs32)))
f8544ec4 HC	83	return -EFAULT;
f8544ec4 HC	84	return 0;
1da177e4 LT	85	}
	86
	87	static int restore_sigregs32(struct pt_regs regs,_sigregs32 __user sregs)
	88	{
4725c860 MS	89	_sigregs32 user_sregs;
4725c860 MS	90	int i;
1da177e4	91
0ecf337f	92	/* Always make any pending restarted system call return -EINTR */
f56141e3	93	current->restart_block.fn = do_no_restart_syscall;
1da177e4	94
4725c860	95	if (__copy_from_user(&user_sregs, &sregs->regs, sizeof(user_sregs)))
f8544ec4	96	return -EFAULT;
4725c860	97
5ebf250d HC	98	if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW32_MASK_RI))
	99	return -EINVAL;
	100
4084eb77 HB	101	/* Test the floating-point-control word. */
4084eb77 HB	102	if (test_fp_ctl(user_sregs.fpregs.fpc))
4725c860 MS	103	return -EINVAL;
	104
	105	/* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */
aa7e04b3	106	regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER \| PSW_MASK_RI)) \|
4725c860	107	(__u64)(user_sregs.regs.psw.mask & PSW32_MASK_USER) << 32 \|
5ebf250d	108	(__u64)(user_sregs.regs.psw.mask & PSW32_MASK_RI) << 32 \|
4725c860	109	(__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_AMODE);
fa968ee2	110	/* Check for invalid user address space control. */
e258d719 MS	111	if ((regs->psw.mask & PSW_MASK_ASC) == PSW_ASC_HOME)
e258d719 MS	112	regs->psw.mask = PSW_ASC_PRIMARY \|
fa968ee2	113	(regs->psw.mask & ~PSW_MASK_ASC);
4725c860	114	regs->psw.addr = (__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_INSN);
1da177e4	115	for (i = 0; i < NUM_GPRS; i++)
4725c860 MS	116	regs->gprs[i] = (__u64) user_sregs.regs.gprs[i];
	117	memcpy(&current->thread.acrs, &user_sregs.regs.acrs,
	118	sizeof(current->thread.acrs));
904818e2	119	fpregs_load((_s390_fp_regs *) &user_sregs.fpregs, &current->thread.fpu);
1da177e4	120
d3a73acb	121	clear_pt_regs_flag(regs, PIF_SYSCALL); /* No longer in a system call */
1da177e4 LT	122	return 0;
	123	}
	124
80703617 MS	125	static int save_sigregs_ext32(struct pt_regs *regs,
80703617 MS	126	_sigregs_ext32 __user *sregs_ext)
ea2a4d3a HC	127	{
ea2a4d3a HC	128	__u32 gprs_high[NUM_GPRS];
80703617	129	__u64 vxrs[__NUM_VXRS_LOW];
ea2a4d3a HC	130	int i;
ea2a4d3a HC	131
80703617	132	/* Save high gprs to signal stack */
ea2a4d3a HC	133	for (i = 0; i < NUM_GPRS; i++)
ea2a4d3a HC	134	gprs_high[i] = regs->gprs[i] >> 32;
80703617 MS	135	if (__copy_to_user(&sregs_ext->gprs_high, &gprs_high,
80703617 MS	136	sizeof(sregs_ext->gprs_high)))
f8544ec4	137	return -EFAULT;
80703617 MS	138
80703617 MS	139	/* Save vector registers to signal stack */
b5510d9b	140	if (MACHINE_HAS_VX) {
80703617	141	for (i = 0; i < __NUM_VXRS_LOW; i++)
a02d584e	142	vxrs[i] = current->thread.fpu.vxrs[i].low;
80703617 MS	143	if (__copy_to_user(&sregs_ext->vxrs_low, vxrs,
	144	sizeof(sregs_ext->vxrs_low)) \|\|
	145	__copy_to_user(&sregs_ext->vxrs_high,
904818e2	146	current->thread.fpu.vxrs + __NUM_VXRS_LOW,
80703617 MS	147	sizeof(sregs_ext->vxrs_high)))
	148	return -EFAULT;
	149	}
f8544ec4	150	return 0;
ea2a4d3a HC	151	}
ea2a4d3a HC	152
80703617 MS	153	static int restore_sigregs_ext32(struct pt_regs *regs,
80703617 MS	154	_sigregs_ext32 __user *sregs_ext)
ea2a4d3a HC	155	{
ea2a4d3a HC	156	__u32 gprs_high[NUM_GPRS];
80703617	157	__u64 vxrs[__NUM_VXRS_LOW];
f8544ec4	158	int i;
ea2a4d3a	159
80703617 MS	160	/* Restore high gprs from signal stack */
80703617 MS	161	if (__copy_from_user(&gprs_high, &sregs_ext->gprs_high,
342300cc	162	sizeof(sregs_ext->gprs_high)))
f8544ec4	163	return -EFAULT;
ea2a4d3a HC	164	for (i = 0; i < NUM_GPRS; i++)
ea2a4d3a HC	165	(__u32 )&regs->gprs[i] = gprs_high[i];
80703617 MS	166
80703617 MS	167	/* Restore vector registers from signal stack */
b5510d9b	168	if (MACHINE_HAS_VX) {
80703617 MS	169	if (__copy_from_user(vxrs, &sregs_ext->vxrs_low,
80703617 MS	170	sizeof(sregs_ext->vxrs_low)) \|\|
904818e2	171	__copy_from_user(current->thread.fpu.vxrs + __NUM_VXRS_LOW,
80703617 MS	172	&sregs_ext->vxrs_high,
	173	sizeof(sregs_ext->vxrs_high)))
	174	return -EFAULT;
	175	for (i = 0; i < __NUM_VXRS_LOW; i++)
a02d584e	176	current->thread.fpu.vxrs[i].low = vxrs[i];
80703617	177	}
ea2a4d3a HC	178	return 0;
	179	}
	180
5b098c20	181	COMPAT_SYSCALL_DEFINE0(sigreturn)
1da177e4	182	{
03ff9a23	183	struct pt_regs *regs = task_pt_regs(current);
1da177e4 LT	184	sigframe32 __user frame = (sigframe32 __user )regs->gprs[15];
	185	sigset_t set;
	186
c60a03fe	187	if (get_compat_sigset(&set, (compat_sigset_t __user *)frame->sc.oldmask))
1da177e4	188	goto badframe;
391c62fe	189	set_current_blocked(&set);
d0164ee2	190	save_fpu_regs();
1da177e4 LT	191	if (restore_sigregs32(regs, &frame->sregs))
1da177e4 LT	192	goto badframe;
80703617	193	if (restore_sigregs_ext32(regs, &frame->sregs_ext))
ea2a4d3a	194	goto badframe;
80703617	195	load_sigregs();
1da177e4	196	return regs->gprs[2];
1da177e4	197	badframe:
3cf5d076	198	force_sig(SIGSEGV);
1da177e4 LT	199	return 0;
	200	}
	201
5b098c20	202	COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
1da177e4	203	{
03ff9a23	204	struct pt_regs *regs = task_pt_regs(current);
1da177e4 LT	205	rt_sigframe32 __user frame = (rt_sigframe32 __user )regs->gprs[15];
1da177e4 LT	206	sigset_t set;
1da177e4	207
c60a03fe	208	if (get_compat_sigset(&set, &frame->uc.uc_sigmask))
1da177e4	209	goto badframe;
391c62fe	210	set_current_blocked(&set);
80703617 MS	211	if (compat_restore_altstack(&frame->uc.uc_stack))
80703617 MS	212	goto badframe;
d0164ee2	213	save_fpu_regs();
1da177e4 LT	214	if (restore_sigregs32(regs, &frame->uc.uc_mcontext))
1da177e4 LT	215	goto badframe;
80703617	216	if (restore_sigregs_ext32(regs, &frame->uc.uc_mcontext_ext))
ea2a4d3a	217	goto badframe;
80703617	218	load_sigregs();
1da177e4	219	return regs->gprs[2];
1da177e4	220	badframe:
3cf5d076	221	force_sig(SIGSEGV);
03ff9a23	222	return 0;
1da177e4 LT	223	}
	224
	225	/*
	226	* Set up a signal frame.
	227	*/
	228
	229
	230	/*
	231	* Determine which stack to use..
	232	*/
	233	static inline void __user *
	234	get_sigframe(struct k_sigaction ka, struct pt_regs regs, size_t frame_size)
	235	{
	236	unsigned long sp;
	237
	238	/* Default to using normal stack */
	239	sp = (unsigned long) A(regs->gprs[15]);
	240
de553438 HC	241	/* Overflow on alternate signal stack gives SIGSEGV. */
	242	if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL))
	243	return (void __user *) -1UL;
	244
1da177e4 LT	245	/* This is the X/Open sanctioned signal stack switching. */
1da177e4 LT	246	if (ka->sa.sa_flags & SA_ONSTACK) {
28f22378	247	if (! sas_ss_flags(sp))
1da177e4 LT	248	sp = current->sas_ss_sp + current->sas_ss_size;
	249	}
	250
1da177e4 LT	251	return (void __user *)((sp - frame_size) & -8ul);
	252	}
	253
067bf2d4 RW	254	static int setup_frame32(struct ksignal ksig, sigset_t set,
067bf2d4 RW	255	struct pt_regs *regs)
1da177e4	256	{
067bf2d4	257	int sig = ksig->sig;
80703617	258	sigframe32 __user *frame;
80703617 MS	259	unsigned long restorer;
	260	size_t frame_size;
	261
	262	/*
	263	* gprs_high are always present for 31-bit compat tasks.
	264	* The space for vector registers is only allocated if
	265	* the machine supports it
	266	*/
	267	frame_size = sizeof(*frame) - sizeof(frame->sregs_ext.__reserved);
	268	if (!MACHINE_HAS_VX)
	269	frame_size -= sizeof(frame->sregs_ext.vxrs_low) +
	270	sizeof(frame->sregs_ext.vxrs_high);
	271	frame = get_sigframe(&ksig->ka, regs, frame_size);
de553438	272	if (frame == (void __user *) -1UL)
067bf2d4	273	return -EFAULT;
de553438	274
80703617 MS	275	/* Set up backchain. */
	276	if (__put_user(regs->gprs[15], (unsigned int __user *) frame))
	277	return -EFAULT;
	278
	279	/* Create struct sigcontext32 on the signal stack */
c60a03fe AV	280	if (put_compat_sigset((compat_sigset_t __user *)frame->sc.oldmask,
	281	set, sizeof(compat_sigset_t)))
	282	return -EFAULT;
8b09ca74	283	if (__put_user(ptr_to_compat(&frame->sregs), &frame->sc.sregs))
067bf2d4	284	return -EFAULT;
1da177e4	285
80703617 MS	286	/* Store registers needed to create the signal frame */
	287	store_sigregs();
	288
	289	/* Create _sigregs32 on the signal stack */
1da177e4	290	if (save_sigregs32(regs, &frame->sregs))
067bf2d4	291	return -EFAULT;
80703617 MS	292
	293	/* Place signal number on stack to allow backtrace from handler. */
	294	if (__put_user(regs->gprs[2], (int __force __user *) &frame->signo))
067bf2d4	295	return -EFAULT;
80703617 MS	296
	297	/* Create _sigregs_ext32 on the signal stack */
	298	if (save_sigregs_ext32(regs, &frame->sregs_ext))
067bf2d4	299	return -EFAULT;
1da177e4 LT	300
	301	/* Set up to return from userspace. If provided, use a stub
	302	already in userspace. */
067bf2d4	303	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
80703617 MS	304	restorer = (unsigned long __force)
80703617 MS	305	ksig->ka.sa.sa_restorer \| PSW32_ADDR_AMODE;
1da177e4	306	} else {
df29a744	307	restorer = VDSO32_SYMBOL(current, sigreturn);
1da177e4 LT	308	}
1da177e4 LT	309
1da177e4	310	/* Set up registers for signal handler */
80703617	311	regs->gprs[14] = restorer;
3c52e49d	312	regs->gprs[15] = (__force __u64) frame;
fa968ee2 MS	313	/* Force 31 bit amode and default user address space control. */
fa968ee2 MS	314	regs->psw.mask = PSW_MASK_BA \|
e258d719	315	(PSW_USER_BITS & PSW_MASK_ASC) \|
fa968ee2	316	(regs->psw.mask & ~PSW_MASK_ASC);
067bf2d4	317	regs->psw.addr = (__force __u64) ksig->ka.sa.sa_handler;
1da177e4	318
6a32591a	319	regs->gprs[2] = sig;
3c52e49d	320	regs->gprs[3] = (__force __u64) &frame->sc;
1da177e4 LT	321
	322	/* We forgot to include these in the sigcontext.
	323	To avoid breaking binary compatibility, they are passed as args. */
aa33c8cb MS	324	if (sig == SIGSEGV \|\| sig == SIGBUS \|\| sig == SIGILL \|\|
	325	sig == SIGTRAP \|\| sig == SIGFPE) {
	326	/* set extra registers only for synchronous signals */
	327	regs->gprs[4] = regs->int_code & 127;
	328	regs->gprs[5] = regs->int_parm_long;
ef280c85	329	regs->gprs[6] = current->thread.last_break;
aa33c8cb	330	}
1da177e4	331
54dfe5dd	332	return 0;
1da177e4 LT	333	}
1da177e4 LT	334
067bf2d4 RW	335	static int setup_rt_frame32(struct ksignal ksig, sigset_t set,
067bf2d4 RW	336	struct pt_regs *regs)
1da177e4	337	{
80703617 MS	338	rt_sigframe32 __user *frame;
	339	unsigned long restorer;
	340	size_t frame_size;
	341	u32 uc_flags;
	342
	343	frame_size = sizeof(*frame) -
	344	sizeof(frame->uc.uc_mcontext_ext.__reserved);
	345	/*
	346	* gprs_high are always present for 31-bit compat tasks.
	347	* The space for vector registers is only allocated if
	348	* the machine supports it
	349	*/
	350	uc_flags = UC_GPRS_HIGH;
	351	if (MACHINE_HAS_VX) {
b5510d9b	352	uc_flags \|= UC_VXRS;
80703617 MS	353	} else
	354	frame_size -= sizeof(frame->uc.uc_mcontext_ext.vxrs_low) +
	355	sizeof(frame->uc.uc_mcontext_ext.vxrs_high);
	356	frame = get_sigframe(&ksig->ka, regs, frame_size);
de553438	357	if (frame == (void __user *) -1UL)
067bf2d4	358	return -EFAULT;
de553438	359
80703617 MS	360	/* Set up backchain. */
80703617 MS	361	if (__put_user(regs->gprs[15], (unsigned int __force __user *) frame))
067bf2d4	362	return -EFAULT;
1da177e4 LT	363
	364	/* Set up to return from userspace. If provided, use a stub
	365	already in userspace. */
067bf2d4	366	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
80703617 MS	367	restorer = (unsigned long __force)
80703617 MS	368	ksig->ka.sa.sa_restorer \| PSW32_ADDR_AMODE;
1da177e4	369	} else {
df29a744	370	restorer = VDSO32_SYMBOL(current, rt_sigreturn);
1da177e4 LT	371	}
1da177e4 LT	372
80703617 MS	373	/* Create siginfo on the signal stack */
	374	if (copy_siginfo_to_user32(&frame->info, &ksig->info))
	375	return -EFAULT;
	376
	377	/* Store registers needed to create the signal frame */
	378	store_sigregs();
	379
	380	/* Create ucontext on the signal stack. */
	381	if (__put_user(uc_flags, &frame->uc.uc_flags) \|\|
	382	__put_user(0, &frame->uc.uc_link) \|\|
	383	__compat_save_altstack(&frame->uc.uc_stack, regs->gprs[15]) \|\|
	384	save_sigregs32(regs, &frame->uc.uc_mcontext) \|\|
c60a03fe	385	put_compat_sigset(&frame->uc.uc_sigmask, set, sizeof(compat_sigset_t)) \|\|
80703617	386	save_sigregs_ext32(regs, &frame->uc.uc_mcontext_ext))
067bf2d4	387	return -EFAULT;
1da177e4 LT	388
1da177e4 LT	389	/* Set up registers for signal handler */
80703617	390	regs->gprs[14] = restorer;
3c52e49d	391	regs->gprs[15] = (__force __u64) frame;
fa968ee2 MS	392	/* Force 31 bit amode and default user address space control. */
fa968ee2 MS	393	regs->psw.mask = PSW_MASK_BA \|
e258d719	394	(PSW_USER_BITS & PSW_MASK_ASC) \|
fa968ee2	395	(regs->psw.mask & ~PSW_MASK_ASC);
067bf2d4	396	regs->psw.addr = (__u64 __force) ksig->ka.sa.sa_handler;
1da177e4	397
6a32591a	398	regs->gprs[2] = ksig->sig;
3c52e49d MS	399	regs->gprs[3] = (__force __u64) &frame->info;
3c52e49d MS	400	regs->gprs[4] = (__force __u64) &frame->uc;
ef280c85	401	regs->gprs[5] = current->thread.last_break;
54dfe5dd	402	return 0;
1da177e4 LT	403	}
	404
	405	/*
	406	* OK, we're invoking a handler
	407	*/
	408
067bf2d4 RW	409	void handle_signal32(struct ksignal ksig, sigset_t oldset,
067bf2d4 RW	410	struct pt_regs *regs)
1da177e4	411	{
54dfe5dd HC	412	int ret;
54dfe5dd HC	413
1da177e4	414	/* Set up the stack frame */
067bf2d4 RW	415	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
067bf2d4 RW	416	ret = setup_rt_frame32(ksig, oldset, regs);
1da177e4	417	else
067bf2d4 RW	418	ret = setup_frame32(ksig, oldset, regs);
	419
	420	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLE_STEP));
1da177e4 LT	421	}
1da177e4 LT	422