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-rw-r--r--arch/mips/kernel/signal32.c606
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);