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/*
* arch/sparc64/kernel/signal.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
* Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#ifdef CONFIG_COMPAT
#include <linux/compat.h> /* for compat_old_sigset_t */
#endif
#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/tracehook.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
#include <linux/bitops.h>
#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/pgtable.h>
#include <asm/fpumacro.h>
#include <asm/uctx.h>
#include <asm/siginfo.h>
#include <asm/visasm.h>
#include <asm/switch_to.h>
#include <asm/cacheflush.h>
#include "entry.h"
#include "systbls.h"
#include "sigutil.h"
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
/* {set, get}context() needed for 64-bit SparcLinux userland. */
asmlinkage void sparc64_set_context(struct pt_regs *regs)
{
struct ucontext __user *ucp = (struct ucontext __user *)
regs->u_regs[UREG_I0];
mc_gregset_t __user *grp;
unsigned long pc, npc, tstate;
unsigned long fp, i7;
unsigned char fenab;
int err;
flush_user_windows();
if (get_thread_wsaved() ||
(((unsigned long)ucp) & (sizeof(unsigned long)-1)) ||
(!__access_ok(ucp, sizeof(*ucp))))
goto do_sigsegv;
grp = &ucp->uc_mcontext.mc_gregs;
err = __get_user(pc, &((*grp)[MC_PC]));
err |= __get_user(npc, &((*grp)[MC_NPC]));
if (err || ((pc | npc) & 3))
goto do_sigsegv;
if (regs->u_regs[UREG_I1]) {
sigset_t set;
if (_NSIG_WORDS == 1) {
if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
goto do_sigsegv;
} else {
if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
goto do_sigsegv;
}
sigdelsetmask(&set, ~_BLOCKABLE);
set_current_blocked(&set);
}
if (test_thread_flag(TIF_32BIT)) {
pc &= 0xffffffff;
npc &= 0xffffffff;
}
regs->tpc = pc;
regs->tnpc = npc;
err |= __get_user(regs->y, &((*grp)[MC_Y]));
err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
/* Skip %g7 as that's the thread register in userspace. */
err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
err |= __put_user(fp,
(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
err |= __put_user(i7,
(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
if (fenab) {
unsigned long *fpregs = current_thread_info()->fpregs;
unsigned long fprs;
fprs_write(0);
err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
if (fprs & FPRS_DL)
err |= copy_from_user(fpregs,
&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
(sizeof(unsigned int) * 32));
if (fprs & FPRS_DU)
err |= copy_from_user(fpregs+16,
((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
(sizeof(unsigned int) * 32));
err |= __get_user(current_thread_info()->xfsr[0],
&(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
err |= __get_user(current_thread_info()->gsr[0],
&(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
regs->tstate &= ~TSTATE_PEF;
}
if (err)
goto do_sigsegv;
return;
do_sigsegv:
force_sig(SIGSEGV, current);
}
asmlinkage void sparc64_get_context(struct pt_regs *regs)
{
struct ucontext __user *ucp = (struct ucontext __user *)
regs->u_regs[UREG_I0];
mc_gregset_t __user *grp;
mcontext_t __user *mcp;
unsigned long fp, i7;
unsigned char fenab;
int err;
synchronize_user_stack();
if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
goto do_sigsegv;
#if 1
fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
#else
fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
#endif
mcp = &ucp->uc_mcontext;
grp = &mcp->mc_gregs;
/* Skip over the trap instruction, first. */
if (test_thread_flag(TIF_32BIT)) {
regs->tpc = (regs->tnpc & 0xffffffff);
regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
} else {
regs->tpc = regs->tnpc;
regs->tnpc += 4;
}
err = 0;
if (_NSIG_WORDS == 1)
err |= __put_user(current->blocked.sig[0],
(unsigned long __user *)&ucp->uc_sigmask);
else
err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
sizeof(sigset_t));
err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
err |= __put_user(regs->y, &((*grp)[MC_Y]));
err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
err |= __get_user(fp,
(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
err |= __get_user(i7,
(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
err |= __put_user(fp, &(mcp->mc_fp));
err |= __put_user(i7, &(mcp->mc_i7));
err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
if (fenab) {
unsigned long *fpregs = current_thread_info()->fpregs;
unsigned long fprs;
fprs = current_thread_info()->fpsaved[0];
if (fprs & FPRS_DL)
err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
(sizeof(unsigned int) * 32));
if (fprs & FPRS_DU)
err |= copy_to_user(
((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
(sizeof(unsigned int) * 32));
err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
}
if (err)
goto do_sigsegv;
return;
do_sigsegv:
force_sig(SIGSEGV, current);
}
struct rt_signal_frame {
struct sparc_stackf ss;
siginfo_t info;
struct pt_regs regs;
__siginfo_fpu_t __user *fpu_save;
stack_t stack;
sigset_t mask;
__siginfo_rwin_t *rwin_save;
};
static long _sigpause_common(old_sigset_t set)
{
sigset_t blocked;
siginitset(&blocked, set);
return sigsuspend(&blocked);
}
asmlinkage long sys_sigpause(unsigned int set)
{
return _sigpause_common(set);
}
asmlinkage long sys_sigsuspend(old_sigset_t set)
{
return _sigpause_common(set);
}
void do_rt_sigreturn(struct pt_regs *regs)
{
struct rt_signal_frame __user *sf;
unsigned long tpc, tnpc, tstate;
__siginfo_fpu_t __user *fpu_save;
__siginfo_rwin_t __user *rwin_save;
sigset_t set;
int err;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
synchronize_user_stack ();
sf = (struct rt_signal_frame __user *)
(regs->u_regs [UREG_FP] + STACK_BIAS);
/* 1. Make sure we are not getting garbage from the user */
if (((unsigned long) sf) & 3)
goto segv;
err = get_user(tpc, &sf->regs.tpc);
err |= __get_user(tnpc, &sf->regs.tnpc);
if (test_thread_flag(TIF_32BIT)) {
tpc &= 0xffffffff;
tnpc &= 0xffffffff;
}
err |= ((tpc | tnpc) & 3);
/* 2. Restore the state */
err |= __get_user(regs->y, &sf->regs.y);
err |= __get_user(tstate, &sf->regs.tstate);
err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
/* User can only change condition codes and %asi in %tstate. */
regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
err |= __get_user(fpu_save, &sf->fpu_save);
if (!err && fpu_save)
err |= restore_fpu_state(regs, fpu_save);
err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
err |= do_sigaltstack(&sf->stack, NULL, (unsigned long)sf);
if (err)
goto segv;
err |= __get_user(rwin_save, &sf->rwin_save);
if (!err && rwin_save) {
if (restore_rwin_state(rwin_save))
goto segv;
}
regs->tpc = tpc;
regs->tnpc = tnpc;
/* Prevent syscall restart. */
pt_regs_clear_syscall(regs);
sigdelsetmask(&set, ~_BLOCKABLE);
set_current_blocked(&set);
return;
segv:
force_sig(SIGSEGV, current);
}
/* Checks if the fp is valid */
static int invalid_frame_pointer(void __user *fp)
{
if (((unsigned long) fp) & 15)
return 1;
return 0;
}
static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, unsigned long framesize)
{
unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
/*
* If we are on the alternate signal stack and would overflow it, don't.
* Return an always-bogus address instead so we will die with SIGSEGV.
*/
if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
return (void __user *) -1L;
/* This is the X/Open sanctioned signal stack switching. */
if (ka->sa.sa_flags & SA_ONSTACK) {
if (sas_ss_flags(sp) == 0)
sp = current->sas_ss_sp + current->sas_ss_size;
}
sp -= framesize;
/* Always align the stack frame. This handles two cases. First,
* sigaltstack need not be mindful of platform specific stack
* alignment. Second, if we took this signal because the stack
* is not aligned properly, we'd like to take the signal cleanly
* and report that.
*/
sp &= ~15UL;
return (void __user *) sp;
}
static inline int
setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
int signo, sigset_t *oldset, siginfo_t *info)
{
struct rt_signal_frame __user *sf;
int wsaved, err, sf_size;
void __user *tail;
/* 1. Make sure everything is clean */
synchronize_user_stack();
save_and_clear_fpu();
wsaved = get_thread_wsaved();
sf_size = sizeof(struct rt_signal_frame);
if (current_thread_info()->fpsaved[0] & FPRS_FEF)
sf_size += sizeof(__siginfo_fpu_t);
if (wsaved)
sf_size += sizeof(__siginfo_rwin_t);
sf = (struct rt_signal_frame __user *)
get_sigframe(ka, regs, sf_size);
if (invalid_frame_pointer (sf))
goto sigill;
tail = (sf + 1);
/* 2. Save the current process state */
err = copy_to_user(&sf->regs, regs, sizeof (*regs));
if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
__siginfo_fpu_t __user *fpu_save = tail;
tail += sizeof(__siginfo_fpu_t);
err |= save_fpu_state(regs, fpu_save);
err |= __put_user((u64)fpu_save, &sf->fpu_save);
} else {
err |= __put_user(0, &sf->fpu_save);
}
if (wsaved) {
__siginfo_rwin_t __user *rwin_save = tail;
tail += sizeof(__siginfo_rwin_t);
err |= save_rwin_state(wsaved, rwin_save);
err |= __put_user((u64)rwin_save, &sf->rwin_save);
set_thread_wsaved(0);
} else {
err |= __put_user(0, &sf->rwin_save);
}
/* Setup sigaltstack */
err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
err |= copy_to_user(&sf->mask, oldset, sizeof(sigset_t));
if (!wsaved) {
err |= copy_in_user((u64 __user *)sf,
(u64 __user *)(regs->u_regs[UREG_FP] +
STACK_BIAS),
sizeof(struct reg_window));
} else {
struct reg_window *rp;
rp = &current_thread_info()->reg_window[wsaved - 1];
err |= copy_to_user(sf, rp, sizeof(struct reg_window));
}
if (info)
err |= copy_siginfo_to_user(&sf->info, info);
else {
err |= __put_user(signo, &sf->info.si_signo);
err |= __put_user(SI_NOINFO, &sf->info.si_code);
}
if (err)
goto sigsegv;
/* 3. signal handler back-trampoline and parameters */
regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
regs->u_regs[UREG_I0] = signo;
regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
/* The sigcontext is passed in this way because of how it
* is defined in GLIBC's /usr/include/bits/sigcontext.h
* for sparc64. It includes the 128 bytes of siginfo_t.
*/
regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
/* 5. signal handler */
regs->tpc = (unsigned long) ka->sa.sa_handler;
regs->tnpc = (regs->tpc + 4);
if (test_thread_flag(TIF_32BIT)) {
regs->tpc &= 0xffffffff;
regs->tnpc &= 0xffffffff;
}
/* 4. return to kernel instructions */
regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
return 0;
sigill:
do_exit(SIGILL);
return -EINVAL;
sigsegv:
force_sigsegv(signo, current);
return -EFAULT;
}
static inline int handle_signal(unsigned long signr, struct k_sigaction *ka,
siginfo_t *info,
sigset_t *oldset, struct pt_regs *regs)
{
int err;
err = setup_rt_frame(ka, regs, signr, oldset,
(ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
if (err)
return err;
block_sigmask(ka, signr);
tracehook_signal_handler(signr, info, ka, regs, 0);
return 0;
}
static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
struct sigaction *sa)
{
switch (regs->u_regs[UREG_I0]) {
case ERESTART_RESTARTBLOCK:
case ERESTARTNOHAND:
no_system_call_restart:
regs->u_regs[UREG_I0] = EINTR;
regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
break;
case ERESTARTSYS:
if (!(sa->sa_flags & SA_RESTART))
goto no_system_call_restart;
/* fallthrough */
case ERESTARTNOINTR:
regs->u_regs[UREG_I0] = orig_i0;
regs->tpc -= 4;
regs->tnpc -= 4;
}
}
/* Note that 'init' is a special process: it doesn't get signals it doesn't
* want to handle. Thus you cannot kill init even with a SIGKILL even by
* mistake.
*/
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
struct k_sigaction ka;
int restart_syscall;
sigset_t *oldset;
siginfo_t info;
int signr;
/* It's a lot of work and synchronization to add a new ptrace
* register for GDB to save and restore in order to get
* orig_i0 correct for syscall restarts when debugging.
*
* Although it should be the case that most of the global
* registers are volatile across a system call, glibc already
* depends upon that fact that we preserve them. So we can't
* just use any global register to save away the orig_i0 value.
*
* In particular %g2, %g3, %g4, and %g5 are all assumed to be
* preserved across a system call trap by various pieces of
* code in glibc.
*
* %g7 is used as the "thread register". %g6 is not used in
* any fixed manner. %g6 is used as a scratch register and
* a compiler temporary, but it's value is never used across
* a system call. Therefore %g6 is usable for orig_i0 storage.
*/
if (pt_regs_is_syscall(regs) &&
(regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
regs->u_regs[UREG_G6] = orig_i0;
if (current_thread_info()->status & TS_RESTORE_SIGMASK)
oldset = &current->saved_sigmask;
else
oldset = &current->blocked;
#ifdef CONFIG_COMPAT
if (test_thread_flag(TIF_32BIT)) {
extern void do_signal32(sigset_t *, struct pt_regs *);
do_signal32(oldset, regs);
return;
}
#endif
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
restart_syscall = 0;
if (pt_regs_is_syscall(regs) &&
(regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
restart_syscall = 1;
orig_i0 = regs->u_regs[UREG_G6];
}
if (signr > 0) {
if (restart_syscall)
syscall_restart(orig_i0, regs, &ka.sa);
if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
/* A signal was successfully delivered; the saved
* sigmask will have been stored in the signal frame,
* and will be restored by sigreturn, so we can simply
* clear the TS_RESTORE_SIGMASK flag.
*/
current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
}
return;
}
if (restart_syscall &&
(regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
regs->u_regs[UREG_I0] == ERESTARTSYS ||
regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
/* replay the system call when we are done */
regs->u_regs[UREG_I0] = orig_i0;
regs->tpc -= 4;
regs->tnpc -= 4;
pt_regs_clear_syscall(regs);
}
if (restart_syscall &&
regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
regs->u_regs[UREG_G1] = __NR_restart_syscall;
regs->tpc -= 4;
regs->tnpc -= 4;
pt_regs_clear_syscall(regs);
}
/* If there's no signal to deliver, we just put the saved sigmask
* back
*/
if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
set_current_blocked(&current->saved_sigmask);
}
}
void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
{
if (thread_info_flags & _TIF_SIGPENDING)
do_signal(regs, orig_i0);
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
if (current->replacement_session_keyring)
key_replace_session_keyring();
}
}
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