/*
* Set up a signal frame for a "real-time" signal handler
* (one which gets siginfo).
*/
static void
handle_rt_signal(unsigned long sig, struct k_sigaction *ka,
siginfo_t *info, sigset_t *oldset, struct pt_regs * regs,
unsigned long newsp)
{
struct rt_sigframe __user *rt_sf;
struct mcontext __user *frame;
unsigned long origsp = newsp;
/* Set up Signal Frame */
/* Put a Real Time Context onto stack */
newsp -= sizeof(*rt_sf);
rt_sf = (struct rt_sigframe __user *) newsp;
/* create a stack frame for the caller of the handler */
newsp -= __SIGNAL_FRAMESIZE + 16;
if (verify_area(VERIFY_WRITE, (void __user *) newsp, origsp - newsp))
goto badframe;
/* Put the siginfo & fill in most of the ucontext */
if (copy_siginfo_to_user(&rt_sf->info, info)
|| __put_user(0, &rt_sf->uc.uc_flags)
|| __put_user(0, &rt_sf->uc.uc_link)
|| __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)
|| __put_user(sas_ss_flags(regs->gpr[1]),
&rt_sf->uc.uc_stack.ss_flags)
|| __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size)
|| __put_user(&rt_sf->uc.uc_mcontext, &rt_sf->uc.uc_regs)
|| __copy_to_user(&rt_sf->uc.uc_sigmask, oldset, sizeof(*oldset)))
goto badframe;
/* Save user registers on the stack */
frame = &rt_sf->uc.uc_mcontext;
if (save_user_regs(regs, frame, __NR_rt_sigreturn))
goto badframe;
if (put_user(regs->gpr[1], (unsigned long __user *)newsp))
goto badframe;
regs->gpr[1] = newsp;
regs->gpr[3] = sig;
regs->gpr[4] = (unsigned long) &rt_sf->info;
regs->gpr[5] = (unsigned long) &rt_sf->uc;
regs->gpr[6] = (unsigned long) rt_sf;
regs->nip = (unsigned long) ka->sa.sa_handler;
regs->link = (unsigned long) frame->tramp;
regs->trap = 0;
return;
badframe:
#ifdef DEBUG_SIG
printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n",
regs, frame, newsp);
#endif
if (sig == SIGSEGV)
ka->sa.sa_handler = SIG_DFL;
force_sig(SIGSEGV, current);
}
/*
* OK, we're invoking a handler
*/
static void
handle_signal(unsigned long sig, struct k_sigaction *ka,
siginfo_t *info, sigset_t *oldset, struct pt_regs * regs,
unsigned long newsp)
{
struct sigcontext __user *sc;
struct sigregs __user *frame;
unsigned long origsp = newsp;
/* Set up Signal Frame */
newsp -= sizeof(struct sigregs);
frame = (struct sigregs __user *) newsp;
/* Put a sigcontext on the stack */
newsp -= sizeof(*sc);
sc = (struct sigcontext __user *) newsp;
/* create a stack frame for the caller of the handler */
newsp -= __SIGNAL_FRAMESIZE;
if (verify_area(VERIFY_WRITE, (void __user *) newsp, origsp - newsp))
goto badframe;
#if _NSIG != 64
#error "Please adjust handle_signal()"
#endif
if (__put_user((unsigned long) ka->sa.sa_handler, &sc->handler)
|| __put_user(oldset->sig[0], &sc->oldmask)
|| __put_user(oldset->sig[1], &sc->_unused[3])
|| __put_user((struct pt_regs *)frame, &sc->regs)
|| __put_user(sig, &sc->signal))
goto badframe;
if (save_user_regs(regs, &frame->mctx, __NR_sigreturn))
goto badframe;
if (put_user(regs->gpr[1], (unsigned long __user *)newsp))
goto badframe;
regs->gpr[1] = newsp;
regs->gpr[3] = sig;
regs->gpr[4] = (unsigned long) sc;
regs->nip = (unsigned long) ka->sa.sa_handler;
regs->link = (unsigned long) frame->mctx.tramp;
regs->trap = 0;
return;
badframe:
#ifdef DEBUG_SIG
printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n",
regs, frame, newsp);
#endif
if (sig == SIGSEGV)
ka->sa.sa_handler = SIG_DFL;
force_sig(SIGSEGV, current);
}
/*
* Set up a signal frame
*/
static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
{
save_user_regs(current->thread.user);
if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
goto badframe;
/* non-iBCS2 extensions.. */
if (__put_user(mask, &sc->sc_oldmask) < 0)
goto badframe;
return 0;
badframe:
return 1;
}
int sys_swapcontext(struct ucontext __user *old_ctx,
struct ucontext __user *new_ctx,
int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
{
unsigned char tmp;
/* Context size is for future use. Right now, we only make sure
* we are passed something we understand
*/
if (ctx_size < sizeof(struct ucontext))
return -EINVAL;
if (old_ctx != NULL) {
if (verify_area(VERIFY_WRITE, old_ctx, sizeof(*old_ctx))
|| save_user_regs(regs, &old_ctx->uc_mcontext, 0)
|| __copy_to_user(&old_ctx->uc_sigmask,
¤t->blocked, sizeof(sigset_t))
|| __put_user(&old_ctx->uc_mcontext, &old_ctx->uc_regs))
return -EFAULT;
}
if (new_ctx == NULL)
return 0;
if (verify_area(VERIFY_READ, new_ctx, sizeof(*new_ctx))
|| __get_user(tmp, (u8 __user *) new_ctx)
|| __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1))
return -EFAULT;
/*
* If we get a fault copying the context into the kernel's
* image of the user's registers, we can't just return -EFAULT
* because the user's registers will be corrupted. For instance
* the NIP value may have been updated but not some of the
* other registers. Given that we have done the verify_area
* and successfully read the first and last bytes of the region
* above, this should only happen in an out-of-memory situation
* or if another thread unmaps the region containing the context.
* We kill the task with a SIGSEGV in this situation.
*/
if (do_setcontext(new_ctx, regs, 0))
do_exit(SIGSEGV);
sigreturn_exit(regs);
/* doesn't actually return back to here */
return 0;
}
