Initial import

1 files changed, 606 insertions, 0 deletions

diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
new file mode 100644
index 000000000..19a7705f2
--- /dev/null
+++ b/arch/mips/kernel/signal32.c
@@ -0,0 +1,606 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1991, 1992  Linus Torvalds
+ * Copyright (C) 1994 - 2000, 2006  Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ */
+#include <linux/cache.h>
+#include <linux/compat.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/syscalls.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/suspend.h>
+#include <linux/compiler.h>
+#include <linux/uaccess.h>
+
+#include <asm/abi.h>
+#include <asm/asm.h>
+#include <asm/compat-signal.h>
+#include <linux/bitops.h>
+#include <asm/cacheflush.h>
+#include <asm/sim.h>
+#include <asm/ucontext.h>
+#include <asm/fpu.h>
+#include <asm/war.h>
+#include <asm/vdso.h>
+#include <asm/dsp.h>
+
+#include "signal-common.h"
+
+static int (*save_fp_context32)(struct sigcontext32 __user *sc);
+static int (*restore_fp_context32)(struct sigcontext32 __user *sc);
+
+extern asmlinkage int _save_fp_context32(struct sigcontext32 __user *sc);
+extern asmlinkage int _restore_fp_context32(struct sigcontext32 __user *sc);
+
+/*
+ * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
+ */
+#define __NR_O32_restart_syscall	4253
+
+/* 32-bit compatibility types */
+
+typedef unsigned int __sighandler32_t;
+typedef void (*vfptr_t)(void);
+
+struct ucontext32 {
+	u32		    uc_flags;
+	s32		    uc_link;
+	compat_stack_t      uc_stack;
+	struct sigcontext32 uc_mcontext;
+	compat_sigset_t	    uc_sigmask;	  /* mask last for extensibility */
+};
+
+struct sigframe32 {
+	u32 sf_ass[4];		/* argument save space for o32 */
+	u32 sf_pad[2];		/* Was: signal trampoline */
+	struct sigcontext32 sf_sc;
+	compat_sigset_t sf_mask;
+};
+
+struct rt_sigframe32 {
+	u32 rs_ass[4];			/* argument save space for o32 */
+	u32 rs_pad[2];			/* Was: signal trampoline */
+	compat_siginfo_t rs_info;
+	struct ucontext32 rs_uc;
+};
+
+/*
+ * Thread saved context copy to/from a signal context presumed to be on the
+ * user stack, and therefore accessed with appropriate macros from uaccess.h.
+ */
+static int copy_fp_to_sigcontext32(struct sigcontext32 __user *sc)
+{
+	int i;
+	int err = 0;
+	int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1;
+
+	for (i = 0; i < NUM_FPU_REGS; i += inc) {
+		err |=
+		    __put_user(get_fpr64(&current->thread.fpu.fpr[i], 0),
+			       &sc->sc_fpregs[i]);
+	}
+	err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
+
+	return err;
+}
+
+static int copy_fp_from_sigcontext32(struct sigcontext32 __user *sc)
+{
+	int i;
+	int err = 0;
+	int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1;
+	u64 fpr_val;
+
+	for (i = 0; i < NUM_FPU_REGS; i += inc) {
+		err |= __get_user(fpr_val, &sc->sc_fpregs[i]);
+		set_fpr64(&current->thread.fpu.fpr[i], 0, fpr_val);
+	}
+	err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
+
+	return err;
+}
+
+/*
+ * sigcontext handlers
+ */
+static int protected_save_fp_context32(struct sigcontext32 __user *sc)
+{
+	int err;
+	while (1) {
+		lock_fpu_owner();
+		if (is_fpu_owner()) {
+			err = save_fp_context32(sc);
+			unlock_fpu_owner();
+		} else {
+			unlock_fpu_owner();
+			err = copy_fp_to_sigcontext32(sc);
+		}
+		if (likely(!err))
+			break;
+		/* touch the sigcontext and try again */
+		err = __put_user(0, &sc->sc_fpregs[0]) |
+			__put_user(0, &sc->sc_fpregs[31]) |
+			__put_user(0, &sc->sc_fpc_csr);
+		if (err)
+			break;	/* really bad sigcontext */
+	}
+	return err;
+}
+
+static int protected_restore_fp_context32(struct sigcontext32 __user *sc)
+{
+	int err, tmp __maybe_unused;
+	while (1) {
+		lock_fpu_owner();
+		if (is_fpu_owner()) {
+			err = restore_fp_context32(sc);
+			unlock_fpu_owner();
+		} else {
+			unlock_fpu_owner();
+			err = copy_fp_from_sigcontext32(sc);
+		}
+		if (likely(!err))
+			break;
+		/* touch the sigcontext and try again */
+		err = __get_user(tmp, &sc->sc_fpregs[0]) |
+			__get_user(tmp, &sc->sc_fpregs[31]) |
+			__get_user(tmp, &sc->sc_fpc_csr);
+		if (err)
+			break;	/* really bad sigcontext */
+	}
+	return err;
+}
+
+static int setup_sigcontext32(struct pt_regs *regs,
+			      struct sigcontext32 __user *sc)
+{
+	int err = 0;
+	int i;
+	u32 used_math;
+
+	err |= __put_user(regs->cp0_epc, &sc->sc_pc);
+
+	err |= __put_user(0, &sc->sc_regs[0]);
+	for (i = 1; i < 32; i++)
+		err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
+
+	err |= __put_user(regs->hi, &sc->sc_mdhi);
+	err |= __put_user(regs->lo, &sc->sc_mdlo);
+	if (cpu_has_dsp) {
+		err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
+		err |= __put_user(mfhi1(), &sc->sc_hi1);
+		err |= __put_user(mflo1(), &sc->sc_lo1);
+		err |= __put_user(mfhi2(), &sc->sc_hi2);
+		err |= __put_user(mflo2(), &sc->sc_lo2);
+		err |= __put_user(mfhi3(), &sc->sc_hi3);
+		err |= __put_user(mflo3(), &sc->sc_lo3);
+	}
+
+	used_math = !!used_math();
+	err |= __put_user(used_math, &sc->sc_used_math);
+
+	if (used_math) {
+		/*
+		 * Save FPU state to signal context.  Signal handler
+		 * will "inherit" current FPU state.
+		 */
+		err |= protected_save_fp_context32(sc);
+	}
+	return err;
+}
+
+static int
+check_and_restore_fp_context32(struct sigcontext32 __user *sc)
+{
+	int err, sig;
+
+	err = sig = fpcsr_pending(&sc->sc_fpc_csr);
+	if (err > 0)
+		err = 0;
+	err |= protected_restore_fp_context32(sc);
+	return err ?: sig;
+}
+
+static int restore_sigcontext32(struct pt_regs *regs,
+				struct sigcontext32 __user *sc)
+{
+	u32 used_math;
+	int err = 0;
+	s32 treg;
+	int i;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current->restart_block.fn = do_no_restart_syscall;
+
+	err |= __get_user(regs->cp0_epc, &sc->sc_pc);
+	err |= __get_user(regs->hi, &sc->sc_mdhi);
+	err |= __get_user(regs->lo, &sc->sc_mdlo);
+	if (cpu_has_dsp) {
+		err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
+		err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
+		err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
+		err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
+		err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
+		err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
+		err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
+	}
+
+	for (i = 1; i < 32; i++)
+		err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
+
+	err |= __get_user(used_math, &sc->sc_used_math);
+	conditional_used_math(used_math);
+
+	if (used_math) {
+		/* restore fpu context if we have used it before */
+		if (!err)
+			err = check_and_restore_fp_context32(sc);
+	} else {
+		/* signal handler may have used FPU.  Give it up. */
+		lose_fpu(0);
+	}
+
+	return err;
+}
+
+/*
+ *
+ */
+extern void __put_sigset_unknown_nsig(void);
+extern void __get_sigset_unknown_nsig(void);
+
+static inline int put_sigset(const sigset_t *kbuf, compat_sigset_t __user *ubuf)
+{
+	int err = 0;
+
+	if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)))
+		return -EFAULT;
+
+	switch (_NSIG_WORDS) {
+	default:
+		__put_sigset_unknown_nsig();
+	case 2:
+		err |= __put_user(kbuf->sig[1] >> 32, &ubuf->sig[3]);
+		err |= __put_user(kbuf->sig[1] & 0xffffffff, &ubuf->sig[2]);
+	case 1:
+		err |= __put_user(kbuf->sig[0] >> 32, &ubuf->sig[1]);
+		err |= __put_user(kbuf->sig[0] & 0xffffffff, &ubuf->sig[0]);
+	}
+
+	return err;
+}
+
+static inline int get_sigset(sigset_t *kbuf, const compat_sigset_t __user *ubuf)
+{
+	int err = 0;
+	unsigned long sig[4];
+
+	if (!access_ok(VERIFY_READ, ubuf, sizeof(*ubuf)))
+		return -EFAULT;
+
+	switch (_NSIG_WORDS) {
+	default:
+		__get_sigset_unknown_nsig();
+	case 2:
+		err |= __get_user(sig[3], &ubuf->sig[3]);
+		err |= __get_user(sig[2], &ubuf->sig[2]);
+		kbuf->sig[1] = sig[2] | (sig[3] << 32);
+	case 1:
+		err |= __get_user(sig[1], &ubuf->sig[1]);
+		err |= __get_user(sig[0], &ubuf->sig[0]);
+		kbuf->sig[0] = sig[0] | (sig[1] << 32);
+	}
+
+	return err;
+}
+
+/*
+ * Atomically swap in the new signal mask, and wait for a signal.
+ */
+
+asmlinkage int sys32_sigsuspend(compat_sigset_t __user *uset)
+{
+	return compat_sys_rt_sigsuspend(uset, sizeof(compat_sigset_t));
+}
+
+SYSCALL_DEFINE3(32_sigaction, long, sig, const struct compat_sigaction __user *, act,
+	struct compat_sigaction __user *, oact)
+{
+	struct k_sigaction new_ka, old_ka;
+	int ret;
+	int err = 0;
+
+	if (act) {
+		old_sigset_t mask;
+		s32 handler;
+
+		if (!access_ok(VERIFY_READ, act, sizeof(*act)))
+			return -EFAULT;
+		err |= __get_user(handler, &act->sa_handler);
+		new_ka.sa.sa_handler = (void __user *)(s64)handler;
+		err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
+		err |= __get_user(mask, &act->sa_mask.sig[0]);
+		if (err)
+			return -EFAULT;
+
+		siginitset(&new_ka.sa.sa_mask, mask);
+	}
+
+	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+
+	if (!ret && oact) {
+		if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
+			return -EFAULT;
+		err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
+		err |= __put_user((u32)(u64)old_ka.sa.sa_handler,
+				  &oact->sa_handler);
+		err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
+		err |= __put_user(0, &oact->sa_mask.sig[1]);
+		err |= __put_user(0, &oact->sa_mask.sig[2]);
+		err |= __put_user(0, &oact->sa_mask.sig[3]);
+		if (err)
+			return -EFAULT;
+	}
+
+	return ret;
+}
+
+int copy_siginfo_to_user32(compat_siginfo_t __user *to, const 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((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;
+}
+
+int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
+{
+	memset(to, 0, sizeof *to);
+
+	if (copy_from_user(to, from, 3*sizeof(int)) ||
+	    copy_from_user(to->_sifields._pad,
+			   from->_sifields._pad, SI_PAD_SIZE32))
+		return -EFAULT;
+
+	return 0;
+}
+
+asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
+{
+	struct sigframe32 __user *frame;
+	sigset_t blocked;
+	int sig;
+
+	frame = (struct sigframe32 __user *) regs.regs[29];
+	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+		goto badframe;
+	if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask))
+		goto badframe;
+
+	set_current_blocked(&blocked);
+
+	sig = restore_sigcontext32(&regs, &frame->sf_sc);
+	if (sig < 0)
+		goto badframe;
+	else if (sig)
+		force_sig(sig, current);
+
+	/*
+	 * Don't let your children do this ...
+	 */
+	__asm__ __volatile__(
+		"move\t$29, %0\n\t"
+		"j\tsyscall_exit"
+		:/* no outputs */
+		:"r" (&regs));
+	/* Unreached */
+
+badframe:
+	force_sig(SIGSEGV, current);
+}
+
+asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
+{
+	struct rt_sigframe32 __user *frame;
+	sigset_t set;
+	int sig;
+
+	frame = (struct rt_sigframe32 __user *) regs.regs[29];
+	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+		goto badframe;
+	if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
+		goto badframe;
+
+	set_current_blocked(&set);
+
+	sig = restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext);
+	if (sig < 0)
+		goto badframe;
+	else if (sig)
+		force_sig(sig, current);
+
+	if (compat_restore_altstack(&frame->rs_uc.uc_stack))
+		goto badframe;
+
+	/*
+	 * Don't let your children do this ...
+	 */
+	__asm__ __volatile__(
+		"move\t$29, %0\n\t"
+		"j\tsyscall_exit"
+		:/* no outputs */
+		:"r" (&regs));
+	/* Unreached */
+
+badframe:
+	force_sig(SIGSEGV, current);
+}
+
+static int setup_frame_32(void *sig_return, struct ksignal *ksig,
+			  struct pt_regs *regs, sigset_t *set)
+{
+	struct sigframe32 __user *frame;
+	int err = 0;
+
+	frame = get_sigframe(ksig, regs, sizeof(*frame));
+	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
+		return -EFAULT;
+
+	err |= setup_sigcontext32(regs, &frame->sf_sc);
+	err |= __copy_conv_sigset_to_user(&frame->sf_mask, set);
+
+	if (err)
+		return -EFAULT;
+
+	/*
+	 * Arguments to signal handler:
+	 *
+	 *   a0 = signal number
+	 *   a1 = 0 (should be cause)
+	 *   a2 = pointer to struct sigcontext
+	 *
+	 * $25 and c0_epc point to the signal handler, $29 points to the
+	 * struct sigframe.
+	 */
+	regs->regs[ 4] = ksig->sig;
+	regs->regs[ 5] = 0;
+	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
+	regs->regs[29] = (unsigned long) frame;
+	regs->regs[31] = (unsigned long) sig_return;
+	regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
+
+	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
+	       current->comm, current->pid,
+	       frame, regs->cp0_epc, regs->regs[31]);
+
+	return 0;
+}
+
+static int setup_rt_frame_32(void *sig_return, struct ksignal *ksig,
+			     struct pt_regs *regs, sigset_t *set)
+{
+	struct rt_sigframe32 __user *frame;
+	int err = 0;
+
+	frame = get_sigframe(ksig, regs, sizeof(*frame));
+	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
+		return -EFAULT;
+
+	/* Convert (siginfo_t -> compat_siginfo_t) and copy to user. */
+	err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info);
+
+	/* Create the ucontext.	 */
+	err |= __put_user(0, &frame->rs_uc.uc_flags);
+	err |= __put_user(0, &frame->rs_uc.uc_link);
+	err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
+	err |= setup_sigcontext32(regs, &frame->rs_uc.uc_mcontext);
+	err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);
+
+	if (err)
+		return -EFAULT;
+
+	/*
+	 * Arguments to signal handler:
+	 *
+	 *   a0 = signal number
+	 *   a1 = 0 (should be cause)
+	 *   a2 = pointer to ucontext
+	 *
+	 * $25 and c0_epc point to the signal handler, $29 points to
+	 * the struct rt_sigframe32.
+	 */
+	regs->regs[ 4] = ksig->sig;
+	regs->regs[ 5] = (unsigned long) &frame->rs_info;
+	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
+	regs->regs[29] = (unsigned long) frame;
+	regs->regs[31] = (unsigned long) sig_return;
+	regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
+
+	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
+	       current->comm, current->pid,
+	       frame, regs->cp0_epc, regs->regs[31]);
+
+	return 0;
+}
+
+/*
+ * o32 compatibility on 64-bit kernels, without DSP ASE
+ */
+struct mips_abi mips_abi_32 = {
+	.setup_frame	= setup_frame_32,
+	.signal_return_offset =
+		offsetof(struct mips_vdso, o32_signal_trampoline),
+	.setup_rt_frame = setup_rt_frame_32,
+	.rt_signal_return_offset =
+		offsetof(struct mips_vdso, o32_rt_signal_trampoline),
+	.restart	= __NR_O32_restart_syscall
+};
+
+static int signal32_init(void)
+{
+	if (cpu_has_fpu) {
+		save_fp_context32 = _save_fp_context32;
+		restore_fp_context32 = _restore_fp_context32;
+	} else {
+		save_fp_context32 = copy_fp_to_sigcontext32;
+		restore_fp_context32 = copy_fp_from_sigcontext32;
+	}
+
+	return 0;
+}
+
+arch_initcall(signal32_init);