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/* $Id: signal.c,v 1.108 2001/01/24 21:05:12 davem Exp $
* linux/arch/sparc/kernel/signal.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
*/
#include <linux/config.h>
#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/smp.h>
#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#include <asm/bitops.h>
#include <asm/ptrace.h>
#include <asm/svr4.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
void *fpqueue, unsigned long *fpqdepth);
extern void fpload(unsigned long *fpregs, unsigned long *fsr);
asmlinkage int do_signal(sigset_t *oldset, struct pt_regs * regs,
unsigned long orig_o0, int ret_from_syscall);
/* This turned off for production... */
/* #define DEBUG_SIGNALS 1 */
/* #define DEBUG_SIGNALS_TRACE 1 */
/* #define DEBUG_SIGNALS_MAPS 1 */
/* 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_sframe {
struct reg_window sig_window;
int sig_num;
int sig_code;
struct sigcontext *sig_scptr;
int sig_address;
struct sigcontext sig_context;
unsigned int extramask[_NSIG_WORDS - 1];
};
/*
* 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_frame {
struct sparc_stackf ss;
__siginfo_t info;
__siginfo_fpu_t *fpu_save;
unsigned long insns [2] __attribute__ ((aligned (8)));
unsigned int extramask[_NSIG_WORDS - 1];
unsigned int extra_size; /* Should be 0 */
__siginfo_fpu_t fpu_state;
};
struct rt_signal_frame {
struct sparc_stackf ss;
siginfo_t info;
struct pt_regs regs;
sigset_t mask;
__siginfo_fpu_t *fpu_save;
unsigned int insns [2];
stack_t stack;
unsigned int extra_size; /* Should be 0 */
__siginfo_fpu_t fpu_state;
};
int copy_siginfo_to_user(siginfo_t *to, siginfo_t *from)
{
if (!access_ok(VERIFY_WRITE, to, sizeof(siginfo_t)))
return -EFAULT;
if (from->si_code < 0)
return __copy_to_user(to, from, sizeof(siginfo_t));
else {
int err;
/* 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. */
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);
switch (from->si_code >> 16) {
case __SI_CHLD >> 16:
err |= __put_user(from->si_utime, &to->si_utime);
err |= __put_user(from->si_stime, &to->si_stime);
/* case __SI_RT: This is not generated by the kernel as of now. */
err |= __put_user(from->si_status, &to->si_status);
default:
err |= __put_user(from->si_uid, &to->si_uid);
err |= __put_user(from->si_pid, &to->si_pid);
break;
}
return err;
}
}
/* Align macros */
#define SF_ALIGNEDSZ (((sizeof(struct signal_sframe) + 7) & (~7)))
#define NF_ALIGNEDSZ (((sizeof(struct new_signal_frame) + 7) & (~7)))
#define RT_ALIGNEDSZ (((sizeof(struct rt_signal_frame) + 7) & (~7)))
/*
* atomically swap in the new signal mask, and wait for a signal.
* This is really tricky on the Sparc, watch out...
*/
asmlinkage void _sigpause_common(old_sigset_t set, struct pt_regs *regs)
{
sigset_t saveset;
set &= _BLOCKABLE;
spin_lock_irq(¤t->sigmask_lock);
saveset = current->blocked;
siginitset(¤t->blocked, set);
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
regs->pc = regs->npc;
regs->npc += 4;
/* 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->psr |= PSR_C;
regs->u_regs[UREG_I0] = EINTR;
if (do_signal(&saveset, regs, 0, 0))
return;
}
}
asmlinkage void do_sigpause(unsigned int set, struct pt_regs *regs)
{
_sigpause_common(set, regs);
}
asmlinkage void do_sigsuspend (struct pt_regs *regs)
{
_sigpause_common(regs->u_regs[UREG_I0], regs);
}
asmlinkage void do_rt_sigsuspend(sigset_t *uset, size_t sigsetsize,
struct pt_regs *regs)
{
sigset_t oldset, set;
/* XXX: Don't preclude handling different sized sigset_t's. */
if (sigsetsize != sizeof(sigset_t)) {
regs->psr |= PSR_C;
regs->u_regs[UREG_I0] = EINVAL;
return;
}
if (copy_from_user(&set, uset, sizeof(set))) {
regs->psr |= PSR_C;
regs->u_regs[UREG_I0] = EFAULT;
return;
}
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sigmask_lock);
oldset = current->blocked;
current->blocked = set;
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
regs->pc = regs->npc;
regs->npc += 4;
/* 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->psr |= PSR_C;
regs->u_regs[UREG_I0] = EINTR;
if (do_signal(&oldset, regs, 0, 0))
return;
}
}
static inline int
restore_fpu_state(struct pt_regs *regs, __siginfo_fpu_t *fpu)
{
int err;
#ifdef CONFIG_SMP
if (current->flags & PF_USEDFPU)
regs->psr &= ~PSR_EF;
#else
if (current == last_task_used_math) {
last_task_used_math = 0;
regs->psr &= ~PSR_EF;
}
#endif
current->used_math = 1;
current->flags &= ~PF_USEDFPU;
if (verify_area (VERIFY_READ, fpu, sizeof(*fpu)))
return -EFAULT;
err = __copy_from_user(¤t->thread.float_regs[0], &fpu->si_float_regs[0],
(sizeof(unsigned long) * 32));
err |= __get_user(current->thread.fsr, &fpu->si_fsr);
err |= __get_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
if (current->thread.fpqdepth != 0)
err |= __copy_from_user(¤t->thread.fpqueue[0],
&fpu->si_fpqueue[0],
((sizeof(unsigned long) +
(sizeof(unsigned long *)))*16));
return err;
}
static inline void do_new_sigreturn (struct pt_regs *regs)
{
struct new_signal_frame *sf;
unsigned long up_psr, pc, npc;
sigset_t set;
__siginfo_fpu_t *fpu_save;
int err;
sf = (struct new_signal_frame *) regs->u_regs [UREG_FP];
/* 1. Make sure we are not getting garbage from the user */
if (verify_area (VERIFY_READ, sf, sizeof (*sf)))
goto segv_and_exit;
if (((uint) sf) & 3)
goto segv_and_exit;
err = __get_user(pc, &sf->info.si_regs.pc);
err |= __get_user(npc, &sf->info.si_regs.npc);
if ((pc | npc) & 3)
goto segv_and_exit;
/* 2. Restore the state */
up_psr = regs->psr;
err |= __copy_from_user(regs, &sf->info.si_regs, sizeof (struct pt_regs));
/* User can only change condition codes and FPU enabling in %psr. */
regs->psr = (up_psr & ~(PSR_ICC | PSR_EF))
| (regs->psr & (PSR_ICC | PSR_EF));
err |= __get_user(fpu_save, &sf->fpu_save);
if (fpu_save)
err |= restore_fpu_state(regs, fpu_save);
/* This is pretty much atomic, no amount locking would prevent
* the races which exist anyways.
*/
err |= __get_user(set.sig[0], &sf->info.si_mask);
err |= __copy_from_user(&set.sig[1], &sf->extramask,
(_NSIG_WORDS-1) * sizeof(unsigned int));
if (err)
goto segv_and_exit;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sigmask_lock);
current->blocked = set;
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
return;
segv_and_exit:
do_exit(SIGSEGV);
}
asmlinkage void do_sigreturn(struct pt_regs *regs)
{
struct sigcontext *scptr;
unsigned long pc, npc, psr;
sigset_t set;
int err;
synchronize_user_stack();
if (current->thread.new_signal)
return do_new_sigreturn (regs);
scptr = (struct sigcontext *) regs->u_regs[UREG_I0];
/* Check sanity of the user arg. */
if(verify_area(VERIFY_READ, scptr, sizeof(struct sigcontext)) ||
(((unsigned long) scptr) & 3))
goto segv_and_exit;
err = __get_user(pc, &scptr->sigc_pc);
err |= __get_user(npc, &scptr->sigc_npc);
if((pc | npc) & 3)
goto segv_and_exit;
/* This is pretty much atomic, no amount locking would prevent
* the races which exist anyways.
*/
err |= __get_user(set.sig[0], &scptr->sigc_mask);
/* Note that scptr + 1 points to extramask */
err |= __copy_from_user(&set.sig[1], scptr + 1,
(_NSIG_WORDS - 1) * sizeof(unsigned int));
if (err)
goto segv_and_exit;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sigmask_lock);
current->blocked = set;
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
regs->pc = pc;
regs->npc = 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 %psr. */
err |= __get_user(psr, &scptr->sigc_psr);
if (err)
goto segv_and_exit;
regs->psr &= ~(PSR_ICC);
regs->psr |= (psr & PSR_ICC);
return;
segv_and_exit:
send_sig(SIGSEGV, current, 1);
}
asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
{
struct rt_signal_frame *sf;
unsigned int psr, pc, npc;
__siginfo_fpu_t *fpu_save;
sigset_t set;
stack_t st;
int err;
synchronize_user_stack();
sf = (struct rt_signal_frame *) regs->u_regs[UREG_FP];
if(verify_area(VERIFY_READ, sf, sizeof(*sf)) ||
(((unsigned long) sf) & 0x03))
goto segv;
err = __get_user(pc, &sf->regs.pc);
err |= __get_user(npc, &sf->regs.npc);
err |= ((pc | npc) & 0x03);
err |= __get_user(regs->y, &sf->regs.y);
err |= __get_user(psr, &sf->regs.psr);
err |= __copy_from_user(®s->u_regs[UREG_G1], &sf->regs.u_regs[UREG_G1], 15*sizeof(u32));
regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC);
err |= __get_user(fpu_save, &sf->fpu_save);
if(fpu_save)
err |= restore_fpu_state(regs, fpu_save);
err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
err |= __copy_from_user(&st, &sf->stack, sizeof(stack_t));
if (err)
goto segv;
regs->pc = pc;
regs->npc = npc;
/* It is more difficult to avoid calling this function than to
call it and ignore errors. */
do_sigaltstack(&st, NULL, (unsigned long)sf);
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sigmask_lock);
current->blocked = set;
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
return;
segv:
send_sig(SIGSEGV, current, 1);
}
/* Checks if the fp is valid */
static inline int invalid_frame_pointer (void *fp, int fplen)
{
if ((((unsigned long) fp) & 7) ||
!__access_ok((unsigned long)fp, fplen) ||
((sparc_cpu_model == sun4 || sparc_cpu_model == sun4c) &&
((unsigned long) fp < 0xe0000000 && (unsigned long) fp >= 0x20000000)))
return 1;
return 0;
}
static inline void *get_sigframe(struct sigaction *sa, struct pt_regs *regs, unsigned long framesize)
{
unsigned long sp;
sp = regs->u_regs[UREG_FP];
/* This is the X/Open sanctioned signal stack switching. */
if (sa->sa_flags & SA_ONSTACK) {
if (!on_sig_stack(sp) && !((current->sas_ss_sp + current->sas_ss_size) & 7))
sp = current->sas_ss_sp + current->sas_ss_size;
}
return (void *)(sp - framesize);
}
static inline void
setup_frame(struct sigaction *sa, struct pt_regs *regs, int signr, sigset_t *oldset, siginfo_t *info)
{
struct signal_sframe *sframep;
struct sigcontext *sc;
int window = 0, err;
unsigned long pc = regs->pc;
unsigned long npc = regs->npc;
void *sig_address;
int sig_code;
synchronize_user_stack();
sframep = (struct signal_sframe *)get_sigframe(sa, regs, SF_ALIGNEDSZ);
if (invalid_frame_pointer (sframep, sizeof(*sframep))){
#ifdef DEBUG_SIGNALS /* fills up the console logs during crashme runs, yuck... */
printk("%s [%d]: User has trashed signal stack\n",
current->comm, current->pid);
printk("Sigstack ptr %p handler at pc<%08lx> for sig<%d>\n",
sframep, pc, signr);
#endif
/* Don't change signal code and address, so that
* post mortem debuggers can have a look.
*/
goto sigill_and_return;
}
sc = &sframep->sig_context;
/* We've already made sure frame pointer isn't in kernel space... */
err = __put_user((sas_ss_flags(regs->u_regs[UREG_FP]) == SS_ONSTACK),
&sc->sigc_onstack);
err |= __put_user(oldset->sig[0], &sc->sigc_mask);
err |= __copy_to_user(sframep->extramask, &oldset->sig[1],
(_NSIG_WORDS - 1) * sizeof(unsigned int));
err |= __put_user(regs->u_regs[UREG_FP], &sc->sigc_sp);
err |= __put_user(pc, &sc->sigc_pc);
err |= __put_user(npc, &sc->sigc_npc);
err |= __put_user(regs->psr, &sc->sigc_psr);
err |= __put_user(regs->u_regs[UREG_G1], &sc->sigc_g1);
err |= __put_user(regs->u_regs[UREG_I0], &sc->sigc_o0);
err |= __put_user(current->thread.w_saved, &sc->sigc_oswins);
if(current->thread.w_saved)
for(window = 0; window < current->thread.w_saved; window++) {
sc->sigc_spbuf[window] =
(char *)current->thread.rwbuf_stkptrs[window];
err |= __copy_to_user(&sc->sigc_wbuf[window],
¤t->thread.reg_window[window],
sizeof(struct reg_window));
}
else
err |= __copy_to_user(sframep, (char *)regs->u_regs[UREG_FP],
sizeof(struct reg_window));
current->thread.w_saved = 0; /* So process is allowed to execute. */
err |= __put_user(signr, &sframep->sig_num);
sig_address = NULL;
sig_code = 0;
if (SI_FROMKERNEL (info) && (info->si_code & __SI_MASK) == __SI_FAULT) {
sig_address = info->si_addr;
switch (signr) {
case SIGSEGV:
switch (info->si_code) {
case SEGV_MAPERR: sig_code = SUBSIG_NOMAPPING; break;
default: sig_code = SUBSIG_PROTECTION; break;
}
break;
case SIGILL:
switch (info->si_code) {
case ILL_ILLOPC: sig_code = SUBSIG_ILLINST; break;
case ILL_PRVOPC: sig_code = SUBSIG_PRIVINST; break;
case ILL_ILLTRP: sig_code = SUBSIG_BADTRAP (info->si_trapno); break;
default: sig_code = SUBSIG_STACK; break;
}
break;
case SIGFPE:
switch (info->si_code) {
case FPE_INTDIV: sig_code = SUBSIG_IDIVZERO; break;
case FPE_INTOVF: sig_code = SUBSIG_FPINTOVFL; break;
case FPE_FLTDIV: sig_code = SUBSIG_FPDIVZERO; break;
case FPE_FLTOVF: sig_code = SUBSIG_FPOVFLOW; break;
case FPE_FLTUND: sig_code = SUBSIG_FPUNFLOW; break;
case FPE_FLTRES: sig_code = SUBSIG_FPINEXACT; break;
case FPE_FLTINV: sig_code = SUBSIG_FPOPERROR; break;
default: sig_code = SUBSIG_FPERROR; break;
}
break;
case SIGBUS:
switch (info->si_code) {
case BUS_ADRALN: sig_code = SUBSIG_ALIGNMENT; break;
case BUS_ADRERR: sig_code = SUBSIG_MISCERROR; break;
default: sig_code = SUBSIG_BUSTIMEOUT; break;
}
break;
case SIGEMT:
switch (info->si_code) {
case EMT_TAGOVF: sig_code = SUBSIG_TAG; break;
}
break;
case SIGSYS:
if (info->si_code == (__SI_FAULT|0x100)) {
/* See sys_sunos.c */
sig_code = info->si_trapno;
break;
}
default:
sig_address = NULL;
}
}
err |= __put_user((long)sig_address, &sframep->sig_address);
err |= __put_user(sig_code, &sframep->sig_code);
err |= __put_user(sc, &sframep->sig_scptr);
if (err)
goto sigsegv;
regs->u_regs[UREG_FP] = (unsigned long) sframep;
regs->pc = (unsigned long) sa->sa_handler;
regs->npc = (regs->pc + 4);
return;
sigill_and_return:
do_exit(SIGILL);
sigsegv:
do_exit(SIGSEGV);
}
static inline int
save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t *fpu)
{
int err = 0;
#ifdef CONFIG_SMP
if (current->flags & PF_USEDFPU) {
put_psr(get_psr() | PSR_EF);
fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
regs->psr &= ~(PSR_EF);
current->flags &= ~(PF_USEDFPU);
}
#else
if (current == last_task_used_math) {
put_psr(get_psr() | PSR_EF);
fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
last_task_used_math = 0;
regs->psr &= ~(PSR_EF);
}
#endif
err |= __copy_to_user(&fpu->si_float_regs[0], ¤t->thread.float_regs[0],
(sizeof(unsigned long) * 32));
err |= __put_user(current->thread.fsr, &fpu->si_fsr);
err |= __put_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
if (current->thread.fpqdepth != 0)
err |= __copy_to_user(&fpu->si_fpqueue[0], ¤t->thread.fpqueue[0],
((sizeof(unsigned long) +
(sizeof(unsigned long *)))*16));
current->used_math = 0;
return err;
}
static inline void
new_setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
int signo, sigset_t *oldset)
{
struct new_signal_frame *sf;
int sigframe_size, err;
/* 1. Make sure everything is clean */
synchronize_user_stack();
sigframe_size = NF_ALIGNEDSZ;
if (!current->used_math)
sigframe_size -= sizeof(__siginfo_fpu_t);
sf = (struct new_signal_frame *)get_sigframe(&ka->sa, regs, sigframe_size);
if (invalid_frame_pointer (sf, sigframe_size))
goto sigill_and_return;
if (current->thread.w_saved != 0) {
#ifdef DEBUG_SIGNALS
printk ("%s [%d]: Invalid user stack frame for "
"signal delivery.\n", current->comm, current->pid);
#endif
goto sigill_and_return;
}
/* 2. Save the current process state */
err = __copy_to_user(&sf->info.si_regs, regs, sizeof (struct pt_regs));
err |= __put_user(0, &sf->extra_size);
if (current->used_math) {
err |= save_fpu_state(regs, &sf->fpu_state);
err |= __put_user(&sf->fpu_state, &sf->fpu_save);
} else {
err |= __put_user(0, &sf->fpu_save);
}
err |= __put_user(oldset->sig[0], &sf->info.si_mask);
err |= __copy_to_user(sf->extramask, &oldset->sig[1],
(_NSIG_WORDS - 1) * sizeof(unsigned int));
err |= __copy_to_user(sf, (char *) regs->u_regs [UREG_FP],
sizeof (struct reg_window));
if (err)
goto sigsegv;
/* 3. signal handler back-trampoline and parameters */
regs->u_regs[UREG_FP] = (unsigned long) sf;
regs->u_regs[UREG_I0] = signo;
regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
/* 4. signal handler */
regs->pc = (unsigned long) ka->sa.sa_handler;
regs->npc = (regs->pc + 4);
/* 5. return to kernel instructions */
if (ka->ka_restorer)
regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
else {
regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2);
/* mov __NR_sigreturn, %g1 */
err |= __put_user(0x821020d8, &sf->insns[0]);
/* t 0x10 */
err |= __put_user(0x91d02010, &sf->insns[1]);
if (err)
goto sigsegv;
/* Flush instruction space. */
flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
}
return;
sigill_and_return:
do_exit(SIGILL);
sigsegv:
do_exit(SIGSEGV);
}
static inline void
new_setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
int signo, sigset_t *oldset, siginfo_t *info)
{
struct rt_signal_frame *sf;
int sigframe_size;
unsigned int psr;
int err;
synchronize_user_stack();
sigframe_size = RT_ALIGNEDSZ;
if(!current->used_math)
sigframe_size -= sizeof(__siginfo_fpu_t);
sf = (struct rt_signal_frame *)get_sigframe(&ka->sa, regs, sigframe_size);
if(invalid_frame_pointer(sf, sigframe_size))
goto sigill;
if(current->thread.w_saved != 0)
goto sigill;
err = __put_user(regs->pc, &sf->regs.pc);
err |= __put_user(regs->npc, &sf->regs.npc);
err |= __put_user(regs->y, &sf->regs.y);
psr = regs->psr;
if(current->used_math)
psr |= PSR_EF;
err |= __put_user(psr, &sf->regs.psr);
err |= __copy_to_user(&sf->regs.u_regs, regs->u_regs, sizeof(regs->u_regs));
err |= __put_user(0, &sf->extra_size);
if(psr & PSR_EF) {
err |= save_fpu_state(regs, &sf->fpu_state);
err |= __put_user(&sf->fpu_state, &sf->fpu_save);
} else {
err |= __put_user(0, &sf->fpu_save);
}
err |= __copy_to_user(&sf->mask, &oldset->sig[0], sizeof(sigset_t));
/* 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, (char *) regs->u_regs [UREG_FP],
sizeof (struct reg_window));
err |= copy_siginfo_to_user(&sf->info, info);
if (err)
goto sigsegv;
regs->u_regs[UREG_FP] = (unsigned long) sf;
regs->u_regs[UREG_I0] = signo;
regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
regs->pc = (unsigned long) ka->sa.sa_handler;
regs->npc = (regs->pc + 4);
if(ka->ka_restorer)
regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
else {
regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2);
/* mov __NR_sigreturn, %g1 */
err |= __put_user(0x821020d8, &sf->insns[0]);
/* t 0x10 */
err |= __put_user(0x91d02010, &sf->insns[1]);
if (err)
goto sigsegv;
/* Flush instruction space. */
flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
}
return;
sigill:
do_exit(SIGILL);
sigsegv:
do_exit(SIGSEGV);
}
/* Setup a Solaris stack frame */
static inline void
setup_svr4_frame(struct sigaction *sa, unsigned long pc, unsigned long npc,
struct pt_regs *regs, int signr, sigset_t *oldset)
{
svr4_signal_frame_t *sfp;
svr4_gregset_t *gr;
svr4_siginfo_t *si;
svr4_mcontext_t *mc;
svr4_gwindows_t *gw;
svr4_ucontext_t *uc;
svr4_sigset_t setv;
int window = 0, err;
synchronize_user_stack();
sfp = (svr4_signal_frame_t *) get_sigframe(sa, regs, SVR4_SF_ALIGNED + REGWIN_SZ);
if (invalid_frame_pointer (sfp, sizeof (*sfp))){
#ifdef DEBUG_SIGNALS
printk ("Invalid stack frame\n");
#endif
goto sigill_and_return;
}
/* Start with a clean frame pointer and fill it */
err = __clear_user(sfp, sizeof (*sfp));
/* Setup convenience variables */
si = &sfp->si;
uc = &sfp->uc;
gw = &sfp->gw;
mc = &uc->mcontext;
gr = &mc->greg;
/* FIXME: where am I supposed to put this?
* sc->sigc_onstack = old_status;
* anyways, it does not look like it is used for anything at all.
*/
setv.sigbits[0] = oldset->sig[0];
setv.sigbits[1] = oldset->sig[1];
if (_NSIG_WORDS >= 4) {
setv.sigbits[2] = oldset->sig[2];
setv.sigbits[3] = oldset->sig[3];
err |= __copy_to_user(&uc->sigmask, &setv, sizeof(svr4_sigset_t));
} else
err |= __copy_to_user(&uc->sigmask, &setv, 2 * sizeof(unsigned int));
/* Store registers */
err |= __put_user(regs->pc, &((*gr) [SVR4_PC]));
err |= __put_user(regs->npc, &((*gr) [SVR4_NPC]));
err |= __put_user(regs->psr, &((*gr) [SVR4_PSR]));
err |= __put_user(regs->y, &((*gr) [SVR4_Y]));
/* Copy g [1..7] and o [0..7] registers */
err |= __copy_to_user(&(*gr)[SVR4_G1], ®s->u_regs [UREG_G1], sizeof (long) * 7);
err |= __copy_to_user(&(*gr)[SVR4_O0], ®s->u_regs [UREG_I0], sizeof (long) * 8);
/* Setup sigaltstack */
err |= __put_user(current->sas_ss_sp, &uc->stack.sp);
err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &uc->stack.flags);
err |= __put_user(current->sas_ss_size, &uc->stack.size);
/* Save the currently window file: */
/* 1. Link sfp->uc->gwins to our windows */
err |= __put_user(gw, &mc->gwin);
/* 2. Number of windows to restore at setcontext (): */
err |= __put_user(current->thread.w_saved, &gw->count);
/* 3. Save each valid window
* Currently, it makes a copy of the windows from the kernel copy.
* David's code for SunOS, makes the copy but keeps the pointer to
* the kernel. My version makes the pointer point to a userland
* copy of those. Mhm, I wonder if I shouldn't just ignore those
* on setcontext and use those that are on the kernel, the signal
* handler should not be modyfing those, mhm.
*
* These windows are just used in case synchronize_user_stack failed
* to flush the user windows.
*/
for(window = 0; window < current->thread.w_saved; window++) {
err |= __put_user((int *) &(gw->win [window]), &gw->winptr [window]);
err |= __copy_to_user(&gw->win [window],
¤t->thread.reg_window [window],
sizeof (svr4_rwindow_t));
err |= __put_user(0, gw->winptr [window]);
}
/* 4. We just pay attention to the gw->count field on setcontext */
current->thread.w_saved = 0; /* So process is allowed to execute. */
/* Setup the signal information. Solaris expects a bunch of
* information to be passed to the signal handler, we don't provide
* that much currently, should use siginfo.
*/
err |= __put_user(signr, &si->siginfo.signo);
err |= __put_user(SVR4_SINOINFO, &si->siginfo.code);
if (err)
goto sigsegv;
regs->u_regs[UREG_FP] = (unsigned long) sfp;
regs->pc = (unsigned long) sa->sa_handler;
regs->npc = (regs->pc + 4);
#ifdef DEBUG_SIGNALS
printk ("Solaris-frame: %x %x\n", (int) regs->pc, (int) regs->npc);
#endif
/* Arguments passed to signal handler */
if (regs->u_regs [14]){
struct reg_window *rw = (struct reg_window *) regs->u_regs [14];
err |= __put_user(signr, &rw->ins [0]);
err |= __put_user(si, &rw->ins [1]);
err |= __put_user(uc, &rw->ins [2]);
err |= __put_user(sfp, &rw->ins [6]); /* frame pointer */
if (err)
goto sigsegv;
regs->u_regs[UREG_I0] = signr;
regs->u_regs[UREG_I1] = (uint) si;
regs->u_regs[UREG_I2] = (uint) uc;
}
return;
sigill_and_return:
do_exit(SIGILL);
sigsegv:
do_exit(SIGSEGV);
}
asmlinkage int svr4_getcontext (svr4_ucontext_t *uc, struct pt_regs *regs)
{
svr4_gregset_t *gr;
svr4_mcontext_t *mc;
svr4_sigset_t setv;
int err = 0;
synchronize_user_stack();
if (current->thread.w_saved)
goto sigsegv_and_return;
err = clear_user(uc, sizeof (*uc));
if (err)
return -EFAULT;
/* Setup convenience variables */
mc = &uc->mcontext;
gr = &mc->greg;
setv.sigbits[0] = current->blocked.sig[0];
setv.sigbits[1] = current->blocked.sig[1];
if (_NSIG_WORDS >= 4) {
setv.sigbits[2] = current->blocked.sig[2];
setv.sigbits[3] = current->blocked.sig[3];
err |= __copy_to_user(&uc->sigmask, &setv, sizeof(svr4_sigset_t));
} else
err |= __copy_to_user(&uc->sigmask, &setv, 2 * sizeof(unsigned int));
/* Store registers */
err |= __put_user(regs->pc, &uc->mcontext.greg [SVR4_PC]);
err |= __put_user(regs->npc, &uc->mcontext.greg [SVR4_NPC]);
err |= __put_user(regs->psr, &uc->mcontext.greg [SVR4_PSR]);
err |= __put_user(regs->y, &uc->mcontext.greg [SVR4_Y]);
/* Copy g [1..7] and o [0..7] registers */
err |= __copy_to_user(&(*gr)[SVR4_G1], ®s->u_regs [UREG_G1], sizeof (uint) * 7);
err |= __copy_to_user(&(*gr)[SVR4_O0], ®s->u_regs [UREG_I0], sizeof (uint) * 8);
/* Setup sigaltstack */
err |= __put_user(current->sas_ss_sp, &uc->stack.sp);
err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &uc->stack.flags);
err |= __put_user(current->sas_ss_size, &uc->stack.size);
/* The register file is not saved
* we have already stuffed all of it with sync_user_stack
*/
return (err ? -EFAULT : 0);
sigsegv_and_return:
do_exit(SIGSEGV);
}
/* Set the context for a svr4 application, this is Solaris way to sigreturn */
asmlinkage int svr4_setcontext (svr4_ucontext_t *c, struct pt_regs *regs)
{
struct thread_struct *tp = ¤t->thread;
svr4_gregset_t *gr;
unsigned long pc, npc, psr;
sigset_t set;
svr4_sigset_t setv;
int err;
stack_t st;
/* Fixme: restore windows, or is this already taken care of in
* svr4_setup_frame when sync_user_windows is done?
*/
flush_user_windows();
if (tp->w_saved)
goto sigsegv_and_return;
if (((uint) c) & 3)
goto sigsegv_and_return;
if(!__access_ok((unsigned long)c, sizeof(*c)))
goto sigsegv_and_return;
/* Check for valid PC and nPC */
gr = &c->mcontext.greg;
err = __get_user(pc, &((*gr)[SVR4_PC]));
err |= __get_user(npc, &((*gr)[SVR4_NPC]));
if((pc | npc) & 3)
goto sigsegv_and_return;
/* Retrieve information from passed ucontext */
/* note that nPC is ored a 1, this is used to inform entry.S */
/* that we don't want it to mess with our PC and nPC */
/* This is pretty much atomic, no amount locking would prevent
* the races which exist anyways.
*/
err |= __copy_from_user(&setv, &c->sigmask, sizeof(svr4_sigset_t));
err |= __get_user(st.ss_sp, &c->stack.sp);
err |= __get_user(st.ss_flags, &c->stack.flags);
err |= __get_user(st.ss_size, &c->stack.size);
if (err)
goto sigsegv_and_return;
/* It is more difficult to avoid calling this function than to
call it and ignore errors. */
do_sigaltstack(&st, NULL, regs->u_regs[UREG_I6]);
set.sig[0] = setv.sigbits[0];
set.sig[1] = setv.sigbits[1];
if (_NSIG_WORDS >= 4) {
set.sig[2] = setv.sigbits[2];
set.sig[3] = setv.sigbits[3];
}
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sigmask_lock);
current->blocked = set;
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
regs->pc = pc;
regs->npc = npc | 1;
err |= __get_user(regs->y, &((*gr) [SVR4_Y]));
err |= __get_user(psr, &((*gr) [SVR4_PSR]));
regs->psr &= ~(PSR_ICC);
regs->psr |= (psr & PSR_ICC);
/* Restore g[1..7] and o[0..7] registers */
err |= __copy_from_user(®s->u_regs [UREG_G1], &(*gr)[SVR4_G1],
sizeof (long) * 7);
err |= __copy_from_user(®s->u_regs [UREG_I0], &(*gr)[SVR4_O0],
sizeof (long) * 8);
return (err ? -EFAULT : 0);
sigsegv_and_return:
do_exit(SIGSEGV);
}
static inline void
handle_signal(unsigned long signr, struct k_sigaction *ka,
siginfo_t *info, sigset_t *oldset, struct pt_regs *regs,
int svr4_signal)
{
if (svr4_signal)
setup_svr4_frame(&ka->sa, regs->pc, regs->npc, regs, signr, oldset);
else {
if (ka->sa.sa_flags & SA_SIGINFO)
new_setup_rt_frame(ka, regs, signr, oldset, info);
else if (current->thread.new_signal)
new_setup_frame (ka, regs, signr, oldset);
else
setup_frame(&ka->sa, regs, signr, oldset, info);
}
if(ka->sa.sa_flags & SA_ONESHOT)
ka->sa.sa_handler = SIG_DFL;
if(!(ka->sa.sa_flags & SA_NOMASK)) {
spin_lock_irq(¤t->sigmask_lock);
sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
sigaddset(¤t->blocked, signr);
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
}
}
static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
struct sigaction *sa)
{
switch(regs->u_regs[UREG_I0]) {
case ERESTARTNOHAND:
no_system_call_restart:
regs->u_regs[UREG_I0] = EINTR;
regs->psr |= PSR_C;
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->pc -= 4;
regs->npc -= 4;
}
}
#ifdef DEBUG_SIGNALS_MAPS
#define MAPS_LINE_FORMAT "%08lx-%08lx %s %08lx %s %lu "
static inline void read_maps (void)
{
struct vm_area_struct * map, * next;
char * buffer;
ssize_t i;
buffer = (char*)__get_free_page(GFP_KERNEL);
if (!buffer)
return;
for (map = current->mm->mmap ; map ; map = next ) {
/* produce the next line */
char *line;
char str[5], *cp = str;
int flags;
kdev_t dev;
unsigned long ino;
/*
* Get the next vma now (but it won't be used if we sleep).
*/
next = map->vm_next;
flags = map->vm_flags;
*cp++ = flags & VM_READ ? 'r' : '-';
*cp++ = flags & VM_WRITE ? 'w' : '-';
*cp++ = flags & VM_EXEC ? 'x' : '-';
*cp++ = flags & VM_MAYSHARE ? 's' : 'p';
*cp++ = 0;
dev = 0;
ino = 0;
if (map->vm_file != NULL) {
dev = map->vm_file->f_dentry->d_inode->i_dev;
ino = map->vm_file->f_dentry->d_inode->i_ino;
line = d_path(map->vm_file->f_dentry,
map->vm_file->f_vfsmnt,
buffer, PAGE_SIZE);
}
printk(MAPS_LINE_FORMAT, map->vm_start, map->vm_end, str, map->vm_pgoff << PAGE_SHIFT,
kdevname(dev), ino);
if (map->vm_file != NULL)
printk("%s\n", line);
else
printk("\n");
}
free_page((unsigned long)buffer);
return;
}
#endif
/* 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.
*/
asmlinkage int do_signal(sigset_t *oldset, struct pt_regs * regs,
unsigned long orig_i0, int restart_syscall)
{
unsigned long signr;
struct k_sigaction *ka;
siginfo_t info;
/*
* XXX Disable svr4 signal handling until solaris emulation works.
* It is buggy - Anton
*/
#define SVR4_SIGNAL_BROKEN 1
#ifdef SVR4_SIGNAL_BROKEN
int svr4_signal = 0;
#else
int svr4_signal = current->personality == PER_SVR4;
#endif
if (!oldset)
oldset = ¤t->blocked;
for (;;) {
spin_lock_irq(¤t->sigmask_lock);
signr = dequeue_signal(¤t->blocked, &info);
spin_unlock_irq(¤t->sigmask_lock);
if (!signr) break;
if ((current->ptrace & PT_PTRACED) && signr != SIGKILL) {
current->exit_code = signr;
current->state = TASK_STOPPED;
/* This happens to be SMP safe so no need to
* grab master kernel lock even in this case.
*/
notify_parent(current, SIGCHLD);
schedule();
if (!(signr = current->exit_code))
continue;
current->exit_code = 0;
if (signr == SIGSTOP)
continue;
/* Update the siginfo structure. Is this good? */
if (signr != info.si_signo) {
info.si_signo = signr;
info.si_errno = 0;
info.si_code = SI_USER;
info.si_pid = current->p_pptr->pid;
info.si_uid = current->p_pptr->uid;
}
/* If the (new) signal is now blocked, requeue it. */
if (sigismember(¤t->blocked, signr)) {
send_sig_info(signr, &info, current);
continue;
}
}
ka = ¤t->sig->action[signr-1];
if(ka->sa.sa_handler == SIG_IGN) {
if(signr != SIGCHLD)
continue;
/* sys_wait4() grabs the master kernel lock, so
* we need not do so, that sucker should be
* threaded and would not be that difficult to
* do anyways.
*/
while(sys_wait4(-1, NULL, WNOHANG, NULL) > 0)
;
continue;
}
if(ka->sa.sa_handler == SIG_DFL) {
unsigned long exit_code = signr;
if(current->pid == 1)
continue;
switch(signr) {
case SIGCONT: case SIGCHLD: case SIGWINCH:
continue;
case SIGTSTP: case SIGTTIN: case SIGTTOU:
/* The operations performed by
* is_orphaned_pgrp() are protected by
* the tasklist_lock.
*/
if (is_orphaned_pgrp(current->pgrp))
continue;
case SIGSTOP:
if (current->ptrace & PT_PTRACED)
continue;
current->state = TASK_STOPPED;
current->exit_code = signr;
/* notify_parent() is SMP safe */
if(!(current->p_pptr->sig->action[SIGCHLD-1].sa.sa_flags &
SA_NOCLDSTOP))
notify_parent(current, SIGCHLD);
schedule();
continue;
case SIGQUIT: case SIGILL: case SIGTRAP:
case SIGABRT: case SIGFPE: case SIGSEGV:
case SIGBUS: case SIGSYS: case SIGXCPU: case SIGXFSZ:
if (do_coredump(signr, regs))
exit_code |= 0x80;
#ifdef DEBUG_SIGNALS
/* Very useful to debug dynamic linker problems */
printk ("Sig %ld going for %s[%d]...\n", signr, current->comm, current->pid);
show_regs (regs);
#ifdef DEBUG_SIGNALS_TRACE
{
struct reg_window *rw = (struct reg_window *)regs->u_regs[UREG_FP];
unsigned int ins[8];
while(rw &&
!(((unsigned long) rw) & 0x3)) {
copy_from_user(ins, &rw->ins[0], sizeof(ins));
printk("Caller[%08x](%08x,%08x,%08x,%08x,%08x,%08x)\n", ins[7], ins[0], ins[1], ins[2], ins[3], ins[4], ins[5]);
rw = (struct reg_window *)(unsigned long)ins[6];
}
}
#endif
#ifdef DEBUG_SIGNALS_MAPS
printk("Maps:\n");
read_maps();
#endif
#endif
/* fall through */
default:
sigaddset(¤t->pending.signal, signr);
recalc_sigpending(current);
current->flags |= PF_SIGNALED;
do_exit(exit_code);
/* NOT REACHED */
}
}
if(restart_syscall)
syscall_restart(orig_i0, regs, &ka->sa);
handle_signal(signr, ka, &info, oldset, regs, svr4_signal);
return 1;
}
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->pc -= 4;
regs->npc -= 4;
}
return 0;
}
asmlinkage int
do_sys_sigstack(struct sigstack *ssptr, struct sigstack *ossptr, unsigned long sp)
{
int ret = -EFAULT;
/* First see if old state is wanted. */
if (ossptr) {
if (put_user(current->sas_ss_sp + current->sas_ss_size, &ossptr->the_stack) ||
__put_user(on_sig_stack(sp), &ossptr->cur_status))
goto out;
}
/* Now see if we want to update the new state. */
if (ssptr) {
void *ss_sp;
if (get_user((long)ss_sp, &ssptr->the_stack))
goto out;
/* If the current stack was set with sigaltstack, don't
swap stacks while we are on it. */
ret = -EPERM;
if (current->sas_ss_sp && on_sig_stack(sp))
goto out;
/* Since we don't know the extent of the stack, and we don't
track onstack-ness, but rather calculate it, we must
presume a size. Ho hum this interface is lossy. */
current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
current->sas_ss_size = SIGSTKSZ;
}
ret = 0;
out:
return ret;
}
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