/*
* Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
* Licensed under the GPL
*/
#include "linux/signal.h"
#include "linux/ptrace.h"
#include "asm/current.h"
#include "asm/ucontext.h"
#include "asm/uaccess.h"
#include "asm/unistd.h"
#include "frame_kern.h"
#include "sigcontext.h"
#include "registers.h"
#include "mode.h"
#ifdef CONFIG_MODE_SKAS
#include "skas.h"
static int copy_sc_from_user_skas(struct pt_regs *regs,
struct sigcontext *from)
{
struct sigcontext sc;
unsigned long fpregs[HOST_FP_SIZE];
int err;
err = copy_from_user(&sc, from, sizeof(sc));
err |= copy_from_user(fpregs, sc.fpstate, sizeof(fpregs));
if(err)
return(err);
REGS_GS(regs->regs.skas.regs) = sc.gs;
REGS_FS(regs->regs.skas.regs) = sc.fs;
REGS_ES(regs->regs.skas.regs) = sc.es;
REGS_DS(regs->regs.skas.regs) = sc.ds;
REGS_EDI(regs->regs.skas.regs) = sc.edi;
REGS_ESI(regs->regs.skas.regs) = sc.esi;
REGS_EBP(regs->regs.skas.regs) = sc.ebp;
REGS_SP(regs->regs.skas.regs) = sc.esp;
REGS_EBX(regs->regs.skas.regs) = sc.ebx;
REGS_EDX(regs->regs.skas.regs) = sc.edx;
REGS_ECX(regs->regs.skas.regs) = sc.ecx;
REGS_EAX(regs->regs.skas.regs) = sc.eax;
REGS_IP(regs->regs.skas.regs) = sc.eip;
REGS_CS(regs->regs.skas.regs) = sc.cs;
REGS_EFLAGS(regs->regs.skas.regs) = sc.eflags;
REGS_SS(regs->regs.skas.regs) = sc.ss;
err = restore_fp_registers(userspace_pid[0], fpregs);
if(err < 0){
printk("copy_sc_from_user_skas - PTRACE_SETFPREGS failed, "
"errno = %d\n", err);
return(1);
}
return(0);
}
int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp,
struct pt_regs *regs)
{
struct sigcontext sc;
unsigned long fpregs[HOST_FP_SIZE];
struct faultinfo * fi = ¤t->thread.arch.faultinfo;
int err;
sc.gs = REGS_GS(regs->regs.skas.regs);
sc.fs = REGS_FS(regs->regs.skas.regs);
sc.es = REGS_ES(regs->regs.skas.regs);
sc.ds = REGS_DS(regs->regs.skas.regs);
sc.edi = REGS_EDI(regs->regs.skas.regs);
sc.esi = REGS_ESI(regs->regs.skas.regs);
sc.ebp = REGS_EBP(regs->regs.skas.regs);
sc.esp = REGS_SP(regs->regs.skas.regs);
sc.ebx = REGS_EBX(regs->regs.skas.regs);
sc.edx = REGS_EDX(regs->regs.skas.regs);
sc.ecx = REGS_ECX(regs->regs.skas.regs);
sc.eax = REGS_EAX(regs->regs.skas.regs);
sc.eip = REGS_IP(regs->regs.skas.regs);
sc.cs = REGS_CS(regs->regs.skas.regs);
sc.eflags = REGS_EFLAGS(regs->regs.skas.regs);
sc.esp_at_signal = regs->regs.skas.regs[UESP];
sc.ss = regs->regs.skas.regs[SS];
sc.cr2 = fi->cr2;
sc.err = fi->error_code;
sc.trapno = fi->trap_no;
err = save_fp_registers(userspace_pid[0], fpregs);
if(err < 0){
printk("copy_sc_to_user_skas - PTRACE_GETFPREGS failed, "
"errno = %d\n", err);
return(1);
}
to_fp = (to_fp ? to_fp : (struct _fpstate *) (to + 1));
sc.fpstate = to_fp;
if(err)
return(err);
return(copy_to_user(to, &sc, sizeof(sc)) ||
copy_to_user(to_fp, fpregs, sizeof(fpregs)));
}
#endif
#ifdef CONFIG_MODE_TT
/* These copy a sigcontext to/from userspace. They copy the fpstate pointer,
* blowing away the old, good one. So, that value is saved, and then restored
* after the sigcontext copy. In copy_from, the variable holding the saved
* fpstate pointer, and the sigcontext that it should be restored to are both
* in the kernel, so we can just restore using an assignment. In copy_to, the
* saved pointer is in the kernel, but the sigcontext is in userspace, so we
* copy_to_user it.
*/
int copy_sc_from_user_tt(struct sigcontext *to, struct sigcontext *from,
int fpsize)
{
struct _fpstate *to_fp, *from_fp;
unsigned long sigs;
int err;
to_fp = to->fpstate;
sigs = to->oldmask;
err = copy_from_user(to, from, sizeof(*to));
from_fp = to->fpstate;
to->oldmask = sigs;
to->fpstate = to_fp;
if(to_fp != NULL)
err |= copy_from_user(to_fp, from_fp, fpsize);
return(err);
}
int copy_sc_to_user_tt(struct sigcontext *to, struct _fpstate *fp,
struct sigcontext *from, int fpsize)
{
struct _fpstate *to_fp, *from_fp;
int err;
to_fp = (fp ? fp : (struct _fpstate *) (to + 1));
from_fp = from->fpstate;
err = copy_to_user(to, from, sizeof(*to));
if(from_fp != NULL){
err |= copy_to_user(&to->fpstate, &to_fp, sizeof(to->fpstate));
err |= copy_to_user(to_fp, from_fp, fpsize);
}
return(err);
}
#endif
static int copy_sc_from_user(struct pt_regs *to, void __user *from)
{
int ret;
ret = CHOOSE_MODE(copy_sc_from_user_tt(UPT_SC(&to->regs), from,
sizeof(struct _fpstate)),
copy_sc_from_user_skas(to, from));
return(ret);
}
static int copy_sc_to_user(struct sigcontext *to, struct _fpstate *fp,
struct pt_regs *from)
{
return(CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs),
sizeof(*fp)),
copy_sc_to_user_skas(to, fp, from)));
}
static int copy_ucontext_to_user(struct ucontext *uc, struct _fpstate *fp,
sigset_t *set, unsigned long sp)
{
int err = 0;
err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs);
err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
return(err);
}
struct sigframe
{
char *pretcode;
int sig;
struct sigcontext sc;
struct _fpstate fpstate;
unsigned long extramask[_NSIG_WORDS-1];
char retcode[8];
};
struct rt_sigframe
{
char *pretcode;
int sig;
struct siginfo *pinfo;
void *puc;
struct siginfo info;
struct ucontext uc;
struct _fpstate fpstate;
char retcode[8];
};
int setup_signal_stack_sc(unsigned long stack_top, int sig,
struct k_sigaction *ka, struct pt_regs *regs,
sigset_t *mask)
{
struct sigframe __user *frame;
void *restorer;
int err = 0;
stack_top &= -8UL;
frame = (struct sigframe *) stack_top - 1;
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
return 1;
restorer = (void *) frame->retcode;
if(ka->sa.sa_flags & SA_RESTORER)
restorer = ka->sa.sa_restorer;
err |= __put_user(restorer, &frame->pretcode);
err |= __put_user(sig, &frame->sig);
err |= copy_sc_to_user(&frame->sc, NULL, regs);
err |= __put_user(mask->sig[0], &frame->sc.oldmask);
if (_NSIG_WORDS > 1)
err |= __copy_to_user(&frame->extramask, &mask->sig[1],
sizeof(frame->extramask));
/*
* This is popl %eax ; movl $,%eax ; int $0x80
*
* WE DO NOT USE IT ANY MORE! It's only left here for historical
* reasons and because gdb uses it as a signature to notice
* signal handler stack frames.
*/
err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
if(err)
return(err);
PT_REGS_SP(regs) = (unsigned long) frame;
PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
PT_REGS_EAX(regs) = (unsigned long) sig;
PT_REGS_EDX(regs) = (unsigned long) 0;
PT_REGS_ECX(regs) = (unsigned long) 0;
if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
ptrace_notify(SIGTRAP);
return(0);
}
int setup_signal_stack_si(unsigned long stack_top, int sig,
struct k_sigaction *ka, struct pt_regs *regs,
siginfo_t *info, sigset_t *mask)
{
struct rt_sigframe __user *frame;
void *restorer;
int err = 0;
stack_top &= -8UL;
frame = (struct rt_sigframe *) stack_top - 1;
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
return 1;
restorer = (void *) frame->retcode;
if(ka->sa.sa_flags & SA_RESTORER)
restorer = ka->sa.sa_restorer;
err |= __put_user(restorer, &frame->pretcode);
err |= __put_user(sig, &frame->sig);
err |= __put_user(&frame->info, &frame->pinfo);
err |= __put_user(&frame->uc, &frame->puc);
err |= copy_siginfo_to_user(&frame->info, info);
err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
PT_REGS_SP(regs));
/*
* This is movl $,%eax ; int $0x80
*
* WE DO NOT USE IT ANY MORE! It's only left here for historical
* reasons and because gdb uses it as a signature to notice
* signal handler stack frames.
*/
err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
if(err)
return(err);
PT_REGS_SP(regs) = (unsigned long) frame;
PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
PT_REGS_EAX(regs) = (unsigned long) sig;
PT_REGS_EDX(regs) = (unsigned long) &frame->info;
PT_REGS_ECX(regs) = (unsigned long) &frame->uc;
if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
ptrace_notify(SIGTRAP);
return(0);
}
long sys_sigreturn(struct pt_regs regs)
{
unsigned long sp = PT_REGS_SP(¤t->thread.regs);
struct sigframe __user *frame = (struct sigframe *)(sp - 8);
sigset_t set;
struct sigcontext __user *sc = &frame->sc;
unsigned long __user *oldmask = &sc->oldmask;
unsigned long __user *extramask = frame->extramask;
int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
if(copy_from_user(&set.sig[0], oldmask, sizeof(set.sig[0])) ||
copy_from_user(&set.sig[1], extramask, sig_size))
goto segfault;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(¤t->sighand->siglock);
if(copy_sc_from_user(¤t->thread.regs, sc))
goto segfault;
/* Avoid ERESTART handling */
PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
return(PT_REGS_SYSCALL_RET(¤t->thread.regs));
segfault:
force_sig(SIGSEGV, current);
return 0;
}
long sys_rt_sigreturn(struct pt_regs regs)
{
unsigned long __user sp = PT_REGS_SP(¤t->thread.regs);
struct rt_sigframe __user *frame = (struct rt_sigframe *) (sp - 4);
sigset_t set;
struct ucontext __user *uc = &frame->uc;
int sig_size = _NSIG_WORDS * sizeof(unsigned long);
if(copy_from_user(&set, &uc->uc_sigmask, sig_size))
goto segfault;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(¤t->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(¤t->sighand->siglock);
if(copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext))
goto segfault;
/* Avoid ERESTART handling */
PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
return(PT_REGS_SYSCALL_RET(¤t->thread.regs));
segfault:
force_sig(SIGSEGV, current);
return 0;
}
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/
