signal32.c

linux-2.6.15.6

/*  $Id: signal32.c,v 1.74 2002/02/09 19:49:30 davem Exp $
 *  arch/sparc64/kernel/signal32.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *  Copyright (C) 1995 David S. Miller ([e-mail])
 *  Copyright (C) 1996 Miguel de Icaza ([e-mail])
 *  Copyright (C) 1997 Eddie C. Dost   ([e-mail])
 *  Copyright (C) 1997,1998 Jakub Jelinek   ([e-mail])
 */

#include <linux/sched.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/mm.h>
#include <linux/tty.h>
#include <linux/smp_lock.h>
#include <linux/binfmts.h>
#include <linux/compat.h>
#include <linux/bitops.h>

#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/svr4.h>
#include <asm/pgtable.h>
#include <asm/psrcompat.h>
#include <asm/fpumacro.h>
#include <asm/visasm.h>

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

int do_signal32(sigset_t *oldset, struct pt_regs *regs,
		unsigned long orig_o0, int ret_from_syscall);

/* Signal frames: the original one (compatible with SunOS):
 *
 * Set up a signal frame... Make the stack look the way SunOS
 * expects it to look which is basically:
 *
 * ---------------------------------- <-- %sp at signal time
 * Struct sigcontext
 * Signal address
 * Ptr to sigcontext area above
 * Signal code
 * The signal number itself
 * One register window
 * ---------------------------------- <-- New %sp
 */
struct signal_sframe32 {
	struct reg_window32 sig_window;
	int sig_num;
	int sig_code;
	/* struct sigcontext32 * */ u32 sig_scptr;
	int sig_address;
	struct sigcontext32 sig_context;
	unsigned int extramask[_COMPAT_NSIG_WORDS - 1];
};

/* This magic should be in g_upper[0] for all upper parts
 * to be valid.
 */
#define SIGINFO_EXTRA_V8PLUS_MAGIC	0x130e269
typedef struct {
	unsigned int g_upper[8];
	unsigned int o_upper[8];
	unsigned int asi;
} siginfo_extra_v8plus_t;

/* 
 * And the new one, intended to be used for Linux applications only
 * (we have enough in there to work with clone).
 * All the interesting bits are in the info field.
 */
struct new_signal_frame32 {
	struct sparc_stackf32	ss;
	__siginfo32_t		info;
	/* __siginfo_fpu32_t * */ u32 fpu_save;
	unsigned int		insns[2];
	unsigned int		extramask[_COMPAT_NSIG_WORDS - 1];
	unsigned int		extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
	/* Only valid if (info.si_regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
	siginfo_extra_v8plus_t	v8plus;
	__siginfo_fpu_t		fpu_state;
};

typedef struct compat_siginfo{
	int si_signo;
	int si_errno;
	int si_code;

	union {
		int _pad[SI_PAD_SIZE32];

		/* kill() */
		struct {
			compat_pid_t _pid;		/* sender's pid */
			unsigned int _uid;		/* sender's uid */
		} _kill;

		/* POSIX.1b timers */
		struct {
			compat_timer_t _tid;			/* timer id */
			int _overrun;			/* overrun count */
			compat_sigval_t _sigval;		/* same as below */
			int _sys_private;		/* not to be passed to user */
		} _timer;

		/* POSIX.1b signals */
		struct {
			compat_pid_t _pid;		/* sender's pid */
			unsigned int _uid;		/* sender's uid */
			compat_sigval_t _sigval;
		} _rt;

		/* SIGCHLD */
		struct {
			compat_pid_t _pid;		/* which child */
			unsigned int _uid;		/* sender's uid */
			int _status;			/* exit code */
			compat_clock_t _utime;
			compat_clock_t _stime;
		} _sigchld;

		/* SIGILL, SIGFPE, SIGSEGV, SIGBUS, SIGEMT */
		struct {
			u32 _addr; /* faulting insn/memory ref. */
			int _trapno;
		} _sigfault;

		/* SIGPOLL */
		struct {
			int _band;	/* POLL_IN, POLL_OUT, POLL_MSG */
			int _fd;
		} _sigpoll;
	} _sifields;
}compat_siginfo_t;

struct rt_signal_frame32 {
	struct sparc_stackf32	ss;
	compat_siginfo_t	info;
	struct pt_regs32	regs;
	compat_sigset_t		mask;
	/* __siginfo_fpu32_t * */ u32 fpu_save;
	unsigned int		insns[2];
	stack_t32		stack;
	unsigned int		extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
	/* Only valid if (regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
	siginfo_extra_v8plus_t	v8plus;
	__siginfo_fpu_t		fpu_state;
};

/* Align macros */
#define SF_ALIGNEDSZ  (((sizeof(struct signal_sframe32) + 7) & (~7)))
#define NF_ALIGNEDSZ  (((sizeof(struct new_signal_frame32) + 7) & (~7)))
#define RT_ALIGNEDSZ  (((sizeof(struct rt_signal_frame32) + 7) & (~7)))

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 be sure
	   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.
	   This routine must convert siginfo from 64bit to 32bit as well
	   at the same time.  */
	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 |= __copy_to_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
	else {
		switch (from->si_code >> 16) {
		case __SI_TIMER >> 16:
			err |= __put_user(from->si_tid, &to->si_tid);
			err |= __put_user(from->si_overrun, &to->si_overrun);
			err |= __put_user(from->si_int, &to->si_int);
			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);
		default:
			err |= __put_user(from->si_pid, &to->si_pid);
			err |= __put_user(from->si_uid, &to->si_uid);
			break;
		case __SI_FAULT >> 16:
			err |= __put_user(from->si_trapno, &to->si_trapno);
			err |= __put_user((unsigned long)from->si_addr, &to->si_addr);
			break;
		case __SI_POLL >> 16:
			err |= __put_user(from->si_band, &to->si_band);
			err |= __put_user(from->si_fd, &to->si_fd);
			break;
		case __SI_RT >> 16: /* This is not generated by the kernel as of now.  */
		case __SI_MESGQ >> 16:
			err |= __put_user(from->si_pid, &to->si_pid);
			err |= __put_user(from->si_uid, &to->si_uid);
			err |= __put_user(from->si_int, &to->si_int);
			break;
		}
	}
	return err;
}

/* CAUTION: This is just a very minimalist implementation for the
 *          sake of compat_sys_rt_sigqueueinfo()
 */
int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
{
	if (!access_ok(VERIFY_WRITE, from, sizeof(compat_siginfo_t)))
		return -EFAULT;

	if (copy_from_user(to, from, 3*sizeof(int)) ||
	    copy_from_user(to->_sifields._pad, from->_sifields._pad,
			   SI_PAD_SIZE))
		return -EFAULT;

	return 0;
}

/*
 * atomically swap in the new signal mask, and wait for a signal.
 * This is really tricky on the Sparc, watch out...
 */
asmlinkage void _sigpause32_common(compat_old_sigset_t set, struct pt_regs *regs)
{
	sigset_t saveset;

	set &= _BLOCKABLE;
	spin_lock_irq(&current->sighand->siglock);
	saveset = current->blocked;
	siginitset(&current->blocked, set);
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	
	regs->tpc = regs->tnpc;
	regs->tnpc += 4;
	if (test_thread_flag(TIF_32BIT)) {
		regs->tpc &= 0xffffffff;
		regs->tnpc &= 0xffffffff;
	}

	/* Condition codes and return value where set here for sigpause,
	 * and so got used by setup_frame, which again causes sigreturn()
	 * to return -EINTR.
	 */
	while (1) {
		current->state = TASK_INTERRUPTIBLE;
		schedule();
		/*
		 * Return -EINTR and set condition code here,
		 * so the interrupted system call actually returns
		 * these.
		 */
		regs->tstate |= TSTATE_ICARRY;
		regs->u_regs[UREG_I0] = EINTR;
		if (do_signal32(&saveset, regs, 0, 0))
			return;
	}
}

asmlinkage void do_rt_sigsuspend32(u32 uset, size_t sigsetsize, struct pt_regs *regs)
{
	sigset_t oldset, set;
	compat_sigset_t set32;
        
	/* XXX: Don't preclude handling different sized sigset_t's.  */
	if (((compat_size_t)sigsetsize) != sizeof(sigset_t)) {
		regs->tstate |= TSTATE_ICARRY;
		regs->u_regs[UREG_I0] = EINVAL;
		return;
	}
	if (copy_from_user(&set32, compat_ptr(uset), sizeof(set32))) {
		regs->tstate |= TSTATE_ICARRY;
		regs->u_regs[UREG_I0] = EFAULT;
		return;
	}
	switch (_NSIG_WORDS) {
	case 4: set.sig[3] = set32.sig[6] + (((long)set32.sig[7]) << 32);
	case 3: set.sig[2] = set32.sig[4] + (((long)set32.sig[5]) << 32);
	case 2: set.sig[1] = set32.sig[2] + (((long)set32.sig[3]) << 32);
	case 1: set.sig[0] = set32.sig[0] + (((long)set32.sig[1]) << 32);
	}
	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	oldset = current->blocked;
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	
	regs->tpc = regs->tnpc;
	regs->tnpc += 4;
	if (test_thread_flag(TIF_32BIT)) {
		regs->tpc &= 0xffffffff;
		regs->tnpc &= 0xffffffff;
	}

	/* Condition codes and return value where set here for sigpause,
	 * and so got used by setup_frame, which again causes sigreturn()
	 * to return -EINTR.
	 */
	while (1) {
		current->state = TASK_INTERRUPTIBLE;
		schedule();
		/*
		 * Return -EINTR and set condition code here,
		 * so the interrupted system call actually returns
		 * these.
		 */
		regs->tstate |= TSTATE_ICARRY;
		regs->u_regs[UREG_I0] = EINTR;
		if (do_signal32(&oldset, regs, 0, 0))
			return;
	}
}

static int restore_fpu_state32(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
	unsigned long *fpregs = current_thread_info()->fpregs;
	unsigned long fprs;
	int err;
	
	err = __get_user(fprs, &fpu->si_fprs);
	fprs_write(0);
	regs->tstate &= ~TSTATE_PEF;
	if (fprs & FPRS_DL)
		err |= copy_from_user(fpregs, &fpu->si_float_regs[0], (sizeof(unsigned int) * 32));
	if (fprs & FPRS_DU)
		err |= copy_from_user(fpregs+16, &fpu->si_float_regs[32], (sizeof(unsigned int) * 32));
	err |= __get_user(current_thread_info()->xfsr[0], &fpu->si_fsr);
	err |= __get_user(current_thread_info()->gsr[0], &fpu->si_gsr);
	current_thread_info()->fpsaved[0] |= fprs;
	return err;
}

void do_new_sigreturn32(struct pt_regs *regs)
{
	struct new_signal_frame32 __user *sf;
	unsigned int psr;
	unsigned pc, npc, fpu_save;
	sigset_t set;
	unsigned seta[_COMPAT_NSIG_WORDS];
	int err, i;
	
	regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
	sf = (struct new_signal_frame32 __user *) regs->u_regs[UREG_FP];

	/* 1. Make sure we are not getting garbage from the user */
	if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
	    (((unsigned long) sf) & 3))
		goto segv;

	get_user(pc, &sf->info.si_regs.pc);
	__get_user(npc, &sf->info.si_regs.npc);

	if ((pc | npc) & 3)
		goto segv;

	if (test_thread_flag(TIF_32BIT)) {
		pc &= 0xffffffff;
		npc &= 0xffffffff;
	}
	regs->tpc = pc;
	regs->tnpc = npc;

	/* 2. Restore the state */
	err = __get_user(regs->y, &sf->info.si_regs.y);
	err |= __get_user(psr, &sf->info.si_regs.psr);

	for (i = UREG_G1; i <= UREG_I7; i++)
		err |= __get_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
	if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
		err |= __get_user(i, &sf->v8plus.g_upper[0]);
		if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
			unsigned long asi;

			for (i = UREG_G1; i <= UREG_I7; i++)
				err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
			err |= __get_user(asi, &sf->v8plus.asi);
			regs->tstate &= ~TSTATE_ASI;
			regs->tstate |= ((asi & 0xffUL) << 24UL);
		}
	}

	/* User can only change condition codes in %tstate. */
	regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
	regs->tstate |= psr_to_tstate_icc(psr);

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (fpu_save)
		err |= restore_fpu_state32(regs, &sf->fpu_state);
	err |= __get_user(seta[0], &sf->info.si_mask);
	err |= copy_from_user(seta+1, &sf->extramask,
			      (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
	if (err)
	    	goto segv;
	switch (_NSIG_WORDS) {
		case 4: set.sig[3] = seta[6] + (((long)seta[7]) << 32);
		case 3: set.sig[2] = seta[4] + (((long)seta[5]) << 32);
		case 2: set.sig[1] = seta[2] + (((long)seta[3]) << 32);
		case 1: set.sig[0] = seta[0] + (((long)seta[1]) << 32);
	}
	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	return;

segv:
	force_sig(SIGSEGV, current);
}

asmlinkage void do_sigreturn32(struct pt_regs *regs)
{
	struct sigcontext32 __user *scptr;
	unsigned int pc, npc, psr;
	sigset_t set;
	unsigned int seta[_COMPAT_NSIG_WORDS];
	int err;

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

	synchronize_user_stack();
	if (test_thread_flag(TIF_NEWSIGNALS)) {
		do_new_sigreturn32(regs);
		return;
	}

	scptr = (struct sigcontext32 __user *)
		(regs->u_regs[UREG_I0] & 0x00000000ffffffffUL);
	/* Check sanity of the user arg. */
	if (!access_ok(VERIFY_READ, scptr, sizeof(struct sigcontext32)) ||
	    (((unsigned long) scptr) & 3))
		goto segv;

	err = __get_user(pc, &scptr->sigc_pc);
	err |= __get_user(npc, &scptr->sigc_npc);

	if ((pc | npc) & 3)
		goto segv; /* Nice try. */

	err |= __get_user(seta[0], &scptr->sigc_mask);
	/* Note that scptr + 1 points to extramask */
	err |= copy_from_user(seta+1, scptr + 1,
			      (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
	if (err)
	    	goto segv;
	switch (_NSIG_WORDS) {
		case 4: set.sig[3] = seta[6] + (((long)seta[7]) << 32);
		case 3: set.sig[2] = seta[4] + (((long)seta[5]) << 32);
		case 2: set.sig[1] = seta[2] + (((long)seta[3]) << 32);
		case 1: set.sig[0] = seta[0] + (((long)seta[1]) << 32);
	}
	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	
	if (test_thread_flag(TIF_32BIT)) {
		pc &= 0xffffffff;
		npc &= 0xffffffff;
	}
	regs->tpc = pc;
	regs->tnpc = npc;
	err = __get_user(regs->u_regs[UREG_FP], &scptr->sigc_sp);
	err |= __get_user(regs->u_regs[UREG_I0], &scptr->sigc_o0);
	err |= __get_user(regs->u_regs[UREG_G1], &scptr->sigc_g1);

	/* User can only change condition codes in %tstate. */
	err |= __get_user(psr, &scptr->sigc_psr);
	if (err)
		goto segv;
	regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
	regs->tstate |= psr_to_tstate_icc(psr);
	return;

segv:
	force_sig(SIGSEGV, current);
}

asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)