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|
/*
* IA32 Architecture-specific signal handling support.
*
* Copyright (C) 1999 Hewlett-Packard Co
* Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
* Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com>
* Copyright (C) 2000 VA Linux Co
* Copyright (C) 2000 Don Dugger <n0ano@valinux.com>
*
* Derived from i386 and Alpha versions.
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/wait.h>
#include <asm/uaccess.h>
#include <asm/rse.h>
#include <asm/sigcontext.h>
#include <asm/segment.h>
#include <asm/ia32.h>
#define DEBUG_SIG 0
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
struct sigframe_ia32
{
int pretcode;
int sig;
struct sigcontext_ia32 sc;
struct _fpstate_ia32 fpstate;
unsigned int extramask[_IA32_NSIG_WORDS-1];
char retcode[8];
};
struct rt_sigframe_ia32
{
int pretcode;
int sig;
int pinfo;
int puc;
struct siginfo info;
struct ucontext_ia32 uc;
struct _fpstate_ia32 fpstate;
char retcode[8];
};
static int
setup_sigcontext_ia32(struct sigcontext_ia32 *sc, struct _fpstate_ia32 *fpstate,
struct pt_regs *regs, unsigned long mask)
{
int err = 0;
err |= __put_user((regs->r16 >> 32) & 0xffff , (unsigned int *)&sc->fs);
err |= __put_user((regs->r16 >> 48) & 0xffff , (unsigned int *)&sc->gs);
err |= __put_user((regs->r16 >> 56) & 0xffff, (unsigned int *)&sc->es);
err |= __put_user(regs->r16 & 0xffff, (unsigned int *)&sc->ds);
err |= __put_user(regs->r15, &sc->edi);
err |= __put_user(regs->r14, &sc->esi);
err |= __put_user(regs->r13, &sc->ebp);
err |= __put_user(regs->r12, &sc->esp);
err |= __put_user(regs->r11, &sc->ebx);
err |= __put_user(regs->r10, &sc->edx);
err |= __put_user(regs->r9, &sc->ecx);
err |= __put_user(regs->r8, &sc->eax);
#if 0
err |= __put_user(current->tss.trap_no, &sc->trapno);
err |= __put_user(current->tss.error_code, &sc->err);
#endif
err |= __put_user(regs->cr_iip, &sc->eip);
err |= __put_user(regs->r17 & 0xffff, (unsigned int *)&sc->cs);
#if 0
err |= __put_user(regs->eflags, &sc->eflags);
#endif
err |= __put_user(regs->r12, &sc->esp_at_signal);
err |= __put_user((regs->r17 >> 16) & 0xffff, (unsigned int *)&sc->ss);
#if 0
tmp = save_i387(fpstate);
if (tmp < 0)
err = 1;
else
err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate);
/* non-iBCS2 extensions.. */
err |= __put_user(mask, &sc->oldmask);
err |= __put_user(current->tss.cr2, &sc->cr2);
#endif
return err;
}
static int
restore_sigcontext_ia32(struct pt_regs *regs, struct sigcontext_ia32 *sc, int *peax)
{
unsigned int err = 0;
#define COPY(ia64x, ia32x) err |= __get_user(regs->ia64x, &sc->ia32x)
#define copyseg_gs(tmp) (regs->r16 |= (unsigned long) tmp << 48)
#define copyseg_fs(tmp) (regs->r16 |= (unsigned long) tmp << 32)
#define copyseg_cs(tmp) (regs->r17 |= tmp)
#define copyseg_ss(tmp) (regs->r17 |= (unsigned long) tmp << 16)
#define copyseg_es(tmp) (regs->r16 |= (unsigned long) tmp << 16)
#define copyseg_ds(tmp) (regs->r16 |= tmp)
#define COPY_SEG(seg) \
{ unsigned short tmp; \
err |= __get_user(tmp, &sc->seg); \
copyseg_##seg(tmp); }
#define COPY_SEG_STRICT(seg) \
{ unsigned short tmp; \
err |= __get_user(tmp, &sc->seg); \
copyseg_##seg(tmp|3); }
/* To make COPY_SEGs easier, we zero r16, r17 */
regs->r16 = 0;
regs->r17 = 0;
COPY_SEG(gs);
COPY_SEG(fs);
COPY_SEG(es);
COPY_SEG(ds);
COPY(r15, edi);
COPY(r14, esi);
COPY(r13, ebp);
COPY(r12, esp);
COPY(r11, ebx);
COPY(r10, edx);
COPY(r9, ecx);
COPY(cr_iip, eip);
COPY_SEG_STRICT(cs);
COPY_SEG_STRICT(ss);
#if 0
{
unsigned int tmpflags;
err |= __get_user(tmpflags, &sc->eflags);
/* XXX: Change this to ar.eflags */
regs->eflags = (regs->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
regs->orig_eax = -1; /* disable syscall checks */
}
{
struct _fpstate * buf;
err |= __get_user(buf, &sc->fpstate);
if (buf) {
if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
goto badframe;
err |= restore_i387(buf);
}
}
#endif
err |= __get_user(*peax, &sc->eax);
return err;
#if 0
badframe:
return 1;
#endif
}
/*
* Determine which stack to use..
*/
static inline void *
get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
{
unsigned long esp;
unsigned int xss;
/* Default to using normal stack */
esp = regs->r12;
xss = regs->r16 >> 16;
/* This is the X/Open sanctioned signal stack switching. */
if (ka->sa.sa_flags & SA_ONSTACK) {
if (! on_sig_stack(esp))
esp = current->sas_ss_sp + current->sas_ss_size;
}
/* Legacy stack switching not supported */
return (void *)((esp - frame_size) & -8ul);
}
static void
setup_frame_ia32(int sig, struct k_sigaction *ka, sigset_t *set,
struct pt_regs * regs)
{
struct sigframe_ia32 *frame;
int err = 0;
frame = get_sigframe(ka, regs, sizeof(*frame));
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
err |= __put_user((current->exec_domain
&& current->exec_domain->signal_invmap
&& sig < 32
? (int)(current->exec_domain->signal_invmap[sig])
: sig),
&frame->sig);
err |= setup_sigcontext_ia32(&frame->sc, &frame->fpstate, regs, set->sig[0]);
if (_NSIG_WORDS > 1) {
err |= __copy_to_user(frame->extramask, &set->sig[1],
sizeof(frame->extramask));
}
/* Set up to return from userspace. If provided, use a stub
already in userspace. */
err |= __put_user(frame->retcode, &frame->pretcode);
/* This is popl %eax ; movl $,%eax ; int $0x80 */
err |= __put_user(0xb858, (short *)(frame->retcode+0));
#define __IA32_NR_sigreturn 119
err |= __put_user(__IA32_NR_sigreturn & 0xffff, (short *)(frame->retcode+2));
err |= __put_user(__IA32_NR_sigreturn >> 16, (short *)(frame->retcode+4));
err |= __put_user(0x80cd, (short *)(frame->retcode+6));
if (err)
goto give_sigsegv;
/* Set up registers for signal handler */
regs->r12 = (unsigned long) frame;
regs->cr_iip = (unsigned long) ka->sa.sa_handler;
set_fs(USER_DS);
regs->r16 = (__USER_DS << 16) | (__USER_DS); /* ES == DS, GS, FS are zero */
regs->r17 = (__USER_DS << 16) | __USER_CS;
#if 0
regs->eflags &= ~TF_MASK;
#endif
#if 1
printk("SIG deliver (%s:%d): sp=%p pc=%lx ra=%x\n",
current->comm, current->pid, frame, regs->cr_iip, frame->pretcode);
#endif
return;
give_sigsegv:
if (sig == SIGSEGV)
ka->sa.sa_handler = SIG_DFL;
force_sig(SIGSEGV, current);
}
static void
setup_rt_frame_ia32(int sig, struct k_sigaction *ka, siginfo_t *info,
sigset_t *set, struct pt_regs * regs)
{
struct rt_sigframe_ia32 *frame;
int err = 0;
frame = get_sigframe(ka, regs, sizeof(*frame));
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
err |= __put_user((current->exec_domain
&& current->exec_domain->signal_invmap
&& sig < 32
? current->exec_domain->signal_invmap[sig]
: sig),
&frame->sig);
err |= __put_user(&frame->info, &frame->pinfo);
err |= __put_user(&frame->uc, &frame->puc);
err |= __copy_to_user(&frame->info, info, sizeof(*info));
/* Create the ucontext. */
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->r12),
&frame->uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
err |= setup_sigcontext_ia32(&frame->uc.uc_mcontext, &frame->fpstate,
regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
err |= __put_user(frame->retcode, &frame->pretcode);
/* This is movl $,%eax ; int $0x80 */
err |= __put_user(0xb8, (char *)(frame->retcode+0));
#define __IA32_NR_rt_sigreturn 173
err |= __put_user(__IA32_NR_rt_sigreturn, (int *)(frame->retcode+1));
err |= __put_user(0x80cd, (short *)(frame->retcode+5));
if (err)
goto give_sigsegv;
/* Set up registers for signal handler */
regs->r12 = (unsigned long) frame;
regs->cr_iip = (unsigned long) ka->sa.sa_handler;
set_fs(USER_DS);
regs->r16 = (__USER_DS << 16) | (__USER_DS); /* ES == DS, GS, FS are zero */
regs->r17 = (__USER_DS << 16) | __USER_CS;
#if 0
regs->eflags &= ~TF_MASK;
#endif
#if 1
printk("SIG deliver (%s:%d): sp=%p pc=%lx ra=%x\n",
current->comm, current->pid, frame, regs->cr_iip, frame->pretcode);
#endif
return;
give_sigsegv:
if (sig == SIGSEGV)
ka->sa.sa_handler = SIG_DFL;
force_sig(SIGSEGV, current);
}
long
ia32_setup_frame1 (int sig, struct k_sigaction *ka, siginfo_t *info,
sigset_t *set, struct pt_regs *regs)
{
/* Set up the stack frame */
if (ka->sa.sa_flags & SA_SIGINFO)
setup_rt_frame_ia32(sig, ka, info, set, regs);
else
setup_frame_ia32(sig, ka, set, regs);
}
asmlinkage int
sys32_sigreturn(
int arg0,
int arg1,
int arg2,
int arg3,
int arg4,
int arg5,
int arg6,
int arg7,
unsigned long stack)
{
struct pt_regs *regs = (struct pt_regs *) &stack;
struct sigframe_ia32 *frame = (struct sigframe_ia32 *)(regs->r12- 8);
sigset_t set;
int eax;
if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__get_user(set.sig[0], &frame->sc.oldmask)
|| (_IA32_NSIG_WORDS > 1
&& __copy_from_user((((char *) &set.sig) + 4),
&frame->extramask,
sizeof(frame->extramask))))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sigmask_lock);
current->blocked = (sigset_t) set;
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
if (restore_sigcontext_ia32(regs, &frame->sc, &eax))
goto badframe;
return eax;
badframe:
force_sig(SIGSEGV, current);
return 0;
}
asmlinkage int
sys32_rt_sigreturn(
int arg0,
int arg1,
int arg2,
int arg3,
int arg4,
int arg5,
int arg6,
int arg7,
unsigned long stack)
{
struct pt_regs *regs = (struct pt_regs *) &stack;
struct rt_sigframe_ia32 *frame = (struct rt_sigframe_ia32 *)(regs->r12 - 4);
sigset_t set;
stack_t st;
int eax;
if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sigmask_lock);
current->blocked = set;
recalc_sigpending(current);
spin_unlock_irq(¤t->sigmask_lock);
if (restore_sigcontext_ia32(regs, &frame->uc.uc_mcontext, &eax))
goto badframe;
if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
goto badframe;
/* It is more difficult to avoid calling this function than to
call it and ignore errors. */
do_sigaltstack(&st, NULL, regs->r12);
return eax;
badframe:
force_sig(SIGSEGV, current);
return 0;
}
|
