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linux/arch/sparc/kernel/signal.c
Steven Rostedt 69be8f1896 [PATCH] convert signal handling of NODEFER to act like other Unix boxes. 
It has been reported that the way Linux handles NODEFER for signals is
not consistent with the way other Unix boxes handle it.  I've written a
program to test the behavior of how this flag affects signals and had
several reports from people who ran this on various Unix boxes,
confirming that Linux seems to be unique on the way this is handled.

The way NODEFER affects signals on other Unix boxes is as follows:

1) If NODEFER is set, other signals in sa_mask are still blocked.

2) If NODEFER is set and the signal is in sa_mask, then the signal is
still blocked. (Note: this is the behavior of all tested but Linux _and_
NetBSD 2.0 *).

The way NODEFER affects signals on Linux:

1) If NODEFER is set, other signals are _not_ blocked regardless of
sa_mask (Even NetBSD doesn't do this).

2) If NODEFER is set and the signal is in sa_mask, then the signal being
handled is not blocked.

The patch converts signal handling in all current Linux architectures to
the way most Unix boxes work.

Unix boxes that were tested:  DU4, AIX 5.2, Irix 6.5, NetBSD 2.0, SFU
3.5 on WinXP, AIX 5.3, Mac OSX, and of course Linux 2.6.13-rcX.

* NetBSD was the only other Unix to behave like Linux on point #2. The
main concern was brought up by point #1 which even NetBSD isn't like
Linux.  So with this patch, we leave NetBSD as the lonely one that
behaves differently here with #2.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-29 10:03:11 -07:00

1181 lines
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/* $Id: signal.c,v 1.110 2002/02/08 03:57:14 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/tty.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/binfmts.h> /* do_coredum */
#include <linux/bitops.h>
#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/svr4.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/cacheflush.h> /* flush_sig_insns */
#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 restart_syscall);
/* 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 __user *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 __user *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 __user *fpu_save;
unsigned int insns[2];
stack_t stack;
unsigned int extra_size; /* Should be 0 */
__siginfo_fpu_t fpu_state;
};
/* 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(&current->sighand->siglock);
saveset = current->blocked;
siginitset(&current->blocked, set);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
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 __user *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(&current->sighand->siglock);
oldset = current->blocked;
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
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 __user *fpu)
{
int err;
#ifdef CONFIG_SMP
if (test_tsk_thread_flag(current, TIF_USEDFPU))
regs->psr &= ~PSR_EF;
#else
if (current == last_task_used_math) {
last_task_used_math = NULL;
regs->psr &= ~PSR_EF;
}
#endif
set_used_math();
clear_tsk_thread_flag(current, TIF_USEDFPU);
if (!access_ok(VERIFY_READ, fpu, sizeof(*fpu)))
return -EFAULT;
err = __copy_from_user(&current->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(&current->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 __user *sf;
unsigned long up_psr, pc, npc;
sigset_t set;
__siginfo_fpu_t __user *fpu_save;
int err;
sf = (struct new_signal_frame __user *) regs->u_regs[UREG_FP];
/* 1. Make sure we are not getting garbage from the user */
if (!access_ok(VERIFY_READ, sf, sizeof(*sf)))
goto segv_and_exit;
if (((unsigned long) 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(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
return;
segv_and_exit:
force_sig(SIGSEGV, current);
}
asmlinkage void do_sigreturn(struct pt_regs *regs)
{
struct sigcontext __user *scptr;
unsigned long pc, npc, psr;
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();
if (current->thread.new_signal) {
do_new_sigreturn(regs);
return;
}
scptr = (struct sigcontext __user *) regs->u_regs[UREG_I0];
/* Check sanity of the user arg. */
if (!access_ok(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(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
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:
force_sig(SIGSEGV, current);
}
asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
{
struct rt_signal_frame __user *sf;
unsigned int psr, pc, npc;
__siginfo_fpu_t __user *fpu_save;
mm_segment_t old_fs;
sigset_t set;
stack_t st;
int err;
synchronize_user_stack();
sf = (struct rt_signal_frame __user *) regs->u_regs[UREG_FP];
if (!access_ok(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(&regs->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.
*/
old_fs = get_fs();
set_fs(KERNEL_DS);
do_sigaltstack((const stack_t __user *) &st, NULL, (unsigned long)sf);
set_fs(old_fs);
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
return;
segv:
force_sig(SIGSEGV, current);
}
/* Checks if the fp is valid */
static inline int invalid_frame_pointer(void __user *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 __user *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 __user *)(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 __user *sframep;
struct sigcontext __user *sc;
int window = 0, err;
unsigned long pc = regs->pc;
unsigned long npc = regs->npc;
struct thread_info *tp = current_thread_info();
void __user *sig_address;
int sig_code;
synchronize_user_stack();
sframep = (struct signal_sframe __user *)
get_sigframe(sa, regs, SF_ALIGNEDSZ);
if (invalid_frame_pointer(sframep, sizeof(*sframep))){
/* 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(tp->w_saved, &sc->sigc_oswins);
if (tp->w_saved)
for (window = 0; window < tp->w_saved; window++) {
put_user((char *)tp->rwbuf_stkptrs[window],
&sc->sigc_spbuf[window]);
err |= __copy_to_user(&sc->sigc_wbuf[window],
&tp->reg_window[window],
sizeof(struct reg_window));
}
else
err |= __copy_to_user(sframep, (char *) regs->u_regs[UREG_FP],
sizeof(struct reg_window));
tp->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((unsigned 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:
force_sigsegv(signr, current);
}
static inline int
save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
int err = 0;
#ifdef CONFIG_SMP
if (test_tsk_thread_flag(current, TIF_USEDFPU)) {
put_psr(get_psr() | PSR_EF);
fpsave(&current->thread.float_regs[0], &current->thread.fsr,
&current->thread.fpqueue[0], &current->thread.fpqdepth);
regs->psr &= ~(PSR_EF);
clear_tsk_thread_flag(current, TIF_USEDFPU);
}
#else
if (current == last_task_used_math) {
put_psr(get_psr() | PSR_EF);
fpsave(&current->thread.float_regs[0], &current->thread.fsr,
&current->thread.fpqueue[0], &current->thread.fpqdepth);
last_task_used_math = NULL;
regs->psr &= ~(PSR_EF);
}
#endif
err |= __copy_to_user(&fpu->si_float_regs[0],
&current->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],
&current->thread.fpqueue[0],
((sizeof(unsigned long) +
(sizeof(unsigned long *)))*16));
clear_used_math();
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 __user *sf;
int sigframe_size, err;
/* 1. Make sure everything is clean */
synchronize_user_stack();
sigframe_size = NF_ALIGNEDSZ;
if (!used_math())
sigframe_size -= sizeof(__siginfo_fpu_t);
sf = (struct new_signal_frame __user *)
get_sigframe(&ka->sa, regs, sigframe_size);
if (invalid_frame_pointer(sf, sigframe_size))
goto sigill_and_return;
if (current_thread_info()->w_saved != 0)
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 (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;
regs->u_regs[UREG_I2] = (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:
force_sigsegv(signo, current);
}
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 __user *sf;
int sigframe_size;
unsigned int psr;
int err;
synchronize_user_stack();
sigframe_size = RT_ALIGNEDSZ;
if (!used_math())
sigframe_size -= sizeof(__siginfo_fpu_t);
sf = (struct rt_signal_frame __user *)
get_sigframe(&ka->sa, regs, sigframe_size);
if (invalid_frame_pointer(sf, sigframe_size))
goto sigill;
if (current_thread_info()->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 (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->u_regs[UREG_I2] = (unsigned long) &sf->regs;
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:
force_sigsegv(signo, current);
}
/* 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 __user *sfp;
svr4_gregset_t __user *gr;
svr4_siginfo_t __user *si;
svr4_mcontext_t __user *mc;
svr4_gwindows_t __user *gw;
svr4_ucontext_t __user *uc;
svr4_sigset_t setv;
struct thread_info *tp = current_thread_info();
int window = 0, err;
synchronize_user_stack();
sfp = (svr4_signal_frame_t __user *)
get_sigframe(sa, regs, SVR4_SF_ALIGNED + sizeof(struct reg_window));
if (invalid_frame_pointer(sfp, sizeof(*sfp)))
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], &regs->u_regs[UREG_G1],
sizeof(long) * 7);
err |= __copy_to_user(&(*gr)[SVR4_O0], &regs->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(tp->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 < tp->w_saved; window++) {
err |= __put_user((int __user *) &(gw->win[window]), &gw->winptr[window]);
err |= __copy_to_user(&gw->win[window],
&tp->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 */
tp->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);
/* Arguments passed to signal handler */
if (regs->u_regs[14]){
struct reg_window __user *rw = (struct reg_window __user *)
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] = (unsigned long) si;
regs->u_regs[UREG_I2] = (unsigned long) uc;
}
return;
sigill_and_return:
do_exit(SIGILL);
sigsegv:
force_sigsegv(signr, current);
}
asmlinkage int svr4_getcontext(svr4_ucontext_t __user *uc, struct pt_regs *regs)
{
svr4_gregset_t __user *gr;
svr4_mcontext_t __user *mc;
svr4_sigset_t setv;
int err = 0;
synchronize_user_stack();
if (current_thread_info()->w_saved)
return -EFAULT;
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], &regs->u_regs[UREG_G1],
sizeof(uint) * 7);
err |= __copy_to_user(&(*gr)[SVR4_O0], &regs->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);
}
/* Set the context for a svr4 application, this is Solaris way to sigreturn */
asmlinkage int svr4_setcontext(svr4_ucontext_t __user *c, struct pt_regs *regs)
{
svr4_gregset_t __user *gr;
unsigned long pc, npc, psr;
mm_segment_t old_fs;
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 (current_thread_info()->w_saved)
goto sigsegv_and_return;
if (((unsigned long) 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. */
old_fs = get_fs();
set_fs(KERNEL_DS);
do_sigaltstack((const stack_t __user *) &st, NULL,
regs->u_regs[UREG_I6]);
set_fs(old_fs);
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(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
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(&regs->u_regs[UREG_G1], &(*gr)[SVR4_G1],
sizeof(long) * 7);
err |= __copy_from_user(&regs->u_regs[UREG_I0], &(*gr)[SVR4_O0],
sizeof(long) * 8);
return (err ? -EFAULT : 0);
sigsegv_and_return:
force_sig(SIGSEGV, current);
return -EFAULT;
}
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);
}
spin_lock_irq(&current->sighand->siglock);
sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NOMASK))
sigaddset(&current->blocked, signr);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
}
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->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;
}
}
/* 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)
{
siginfo_t info;
struct sparc_deliver_cookie cookie;
struct k_sigaction ka;
int signr;
/*
* 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
cookie.restart_syscall = restart_syscall;
cookie.orig_i0 = orig_i0;
if (!oldset)
oldset = &current->blocked;
signr = get_signal_to_deliver(&info, &ka, regs, &cookie);
if (signr > 0) {
if (cookie.restart_syscall)
syscall_restart(cookie.orig_i0, regs, &ka.sa);
handle_signal(signr, &ka, &info, oldset,
regs, svr4_signal);
return 1;
}
if (cookie.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] = cookie.orig_i0;
regs->pc -= 4;
regs->npc -= 4;
}
if (cookie.restart_syscall &&
regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
regs->u_regs[UREG_G1] = __NR_restart_syscall;
regs->pc -= 4;
regs->npc -= 4;
}
return 0;
}
asmlinkage int
do_sys_sigstack(struct sigstack __user *ssptr, struct sigstack __user *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) {
char *ss_sp;
if (get_user(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;
}
void ptrace_signal_deliver(struct pt_regs *regs, void *cookie)
{
struct sparc_deliver_cookie *cp = cookie;
if (cp->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] = cp->orig_i0;
regs->pc -= 4;
regs->npc -= 4;
cp->restart_syscall = 0;
}
if (cp->restart_syscall &&
regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
regs->u_regs[UREG_G1] = __NR_restart_syscall;
regs->pc -= 4;
regs->npc -= 4;
cp->restart_syscall = 0;
}
}
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