/*
* OK, we're invoking a handler
*/
static int handle_signal(struct pt_regs *regs, unsigned long signr,
struct k_sigaction *ka, siginfo_t *info,
sigset_t *oldset)
{
unsigned long sp;
int err;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
/* Did we come from a system call? */
if (PT_REGS_SYSCALL_NR(regs) >= 0) {
/* If so, check system call restarting.. */
switch (PT_REGS_SYSCALL_RET(regs)) {
case -ERESTART_RESTARTBLOCK:
case -ERESTARTNOHAND:
PT_REGS_SYSCALL_RET(regs) = -EINTR;
break;
case -ERESTARTSYS:
if (!(ka->sa.sa_flags & SA_RESTART)) {
PT_REGS_SYSCALL_RET(regs) = -EINTR;
break;
}
/* fallthrough */
case -ERESTARTNOINTR:
PT_REGS_RESTART_SYSCALL(regs);
PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs);
break;
}
}
sp = PT_REGS_SP(regs);
if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags(sp) == 0))
sp = current->sas_ss_sp + current->sas_ss_size;
#ifdef CONFIG_ARCH_HAS_SC_SIGNALS
if (!(ka->sa.sa_flags & SA_SIGINFO))
err = setup_signal_stack_sc(sp, signr, ka, regs, oldset);
else
#endif
err = setup_signal_stack_si(sp, signr, ka, regs, info, oldset);
if (err)
force_sigsegv(signr, current);
else
block_sigmask(ka, signr);
return err;
}
long sys_rt_sigreturn(struct pt_regs regs)
{
unsigned long sp = PT_REGS_SP(¤t->thread.regs);
struct rt_sigframe __user *frame = (struct rt_sigframe __user *) (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;
}
long sys_sigreturn(struct pt_regs regs)
{
unsigned long sp = PT_REGS_SP(¤t->thread.regs);
struct sigframe __user *frame = (struct sigframe __user *)(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;
}
static int kern_do_signal(struct pt_regs *regs, sigset_t *oldset, int error)
{
siginfo_t info;
struct k_sigaction *ka;
int err, sig;
if (!oldset)
oldset = ¤t->blocked;
sig = get_signal_to_deliver(&info, regs, NULL);
if(sig == 0)
return(0);
/* Whee! Actually deliver the signal. */
ka = ¤t->sig->action[sig -1 ];
err = handle_signal(regs, sig, ka, &info, oldset, error);
if(!err) return(1);
/* Did we come from a system call? */
if(PT_REGS_SYSCALL_NR(regs) >= 0){
/* Restart the system call - no handlers present */
if(PT_REGS_SYSCALL_RET(regs) == -ERESTARTNOHAND ||
PT_REGS_SYSCALL_RET(regs) == -ERESTARTSYS ||
PT_REGS_SYSCALL_RET(regs) == -ERESTARTNOINTR){
PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs);
PT_REGS_RESTART_SYSCALL(regs);
}
else if(PT_REGS_SYSCALL_RET(regs) == -ERESTART_RESTARTBLOCK){
PT_REGS_SYSCALL_RET(regs) = __NR_restart_syscall;
PT_REGS_RESTART_SYSCALL(regs);
}
}
/* This closes a way to execute a system call on the host. If
* you set a breakpoint on a system call instruction and singlestep
* from it, the tracing thread used to PTRACE_SINGLESTEP the process
* rather than PTRACE_SYSCALL it, allowing the system call to execute
* on the host. The tracing thread will check this flag and
* PTRACE_SYSCALL if necessary.
*/
if((current->ptrace & PT_DTRACE) &&
is_syscall(PT_REGS_IP(¤t->thread.regs)))
(void) CHOOSE_MODE(current->thread.mode.tt.singlestep_syscall = 1, 0);
return(0);
}
/*
* OK, we're invoking a handler
*/
static void handle_signal(struct pt_regs *regs, unsigned long signr,
struct k_sigaction *ka, siginfo_t *info)
{
sigset_t *oldset = sigmask_to_save();
unsigned long sp;
int err;
/* Did we come from a system call? */
if (PT_REGS_SYSCALL_NR(regs) >= 0) {
/* If so, check system call restarting.. */
switch (PT_REGS_SYSCALL_RET(regs)) {
case -ERESTART_RESTARTBLOCK:
case -ERESTARTNOHAND:
PT_REGS_SYSCALL_RET(regs) = -EINTR;
break;
case -ERESTARTSYS:
if (!(ka->sa.sa_flags & SA_RESTART)) {
PT_REGS_SYSCALL_RET(regs) = -EINTR;
break;
}
/* fallthrough */
case -ERESTARTNOINTR:
PT_REGS_RESTART_SYSCALL(regs);
PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs);
break;
}
}
sp = PT_REGS_SP(regs);
if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags(sp) == 0))
sp = current->sas_ss_sp + current->sas_ss_size;
#ifdef CONFIG_ARCH_HAS_SC_SIGNALS
if (!(ka->sa.sa_flags & SA_SIGINFO))
err = setup_signal_stack_sc(sp, signr, ka, regs, oldset);
else
#endif
err = setup_signal_stack_si(sp, signr, ka, regs, info, oldset);
if (err)
force_sigsegv(signr, current);
else
signal_delivered(signr, info, ka, regs, 0);
}
static int kern_do_signal(struct pt_regs *regs)
{
struct k_sigaction ka_copy;
siginfo_t info;
sigset_t *oldset;
int sig, handled_sig = 0;
if (test_thread_flag(TIF_RESTORE_SIGMASK))
oldset = ¤t->saved_sigmask;
else
oldset = ¤t->blocked;
while ((sig = get_signal_to_deliver(&info, &ka_copy, regs, NULL)) > 0) {
handled_sig = 1;
/* Whee! Actually deliver the signal. */
handle_signal(regs, sig, &ka_copy, &info);
}
/* Did we come from a system call? */
if (!handled_sig && (PT_REGS_SYSCALL_NR(regs) >= 0)) {
/* Restart the system call - no handlers present */
switch (PT_REGS_SYSCALL_RET(regs)) {
case -ERESTARTNOHAND:
case -ERESTARTSYS:
case -ERESTARTNOINTR:
PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs);
PT_REGS_RESTART_SYSCALL(regs);
break;
case -ERESTART_RESTARTBLOCK:
PT_REGS_ORIG_SYSCALL(regs) = __NR_restart_syscall;
PT_REGS_RESTART_SYSCALL(regs);
break;
}
}
/*
* This closes a way to execute a system call on the host. If
* you set a breakpoint on a system call instruction and singlestep
* from it, the tracing thread used to PTRACE_SINGLESTEP the process
* rather than PTRACE_SYSCALL it, allowing the system call to execute
* on the host. The tracing thread will check this flag and
* PTRACE_SYSCALL if necessary.
*/
if (current->ptrace & PT_DTRACE)
current->thread.singlestep_syscall =
is_syscall(PT_REGS_IP(¤t->thread.regs));
/*
* if there's no signal to deliver, we just put the saved sigmask
* back
*/
if (!handled_sig)
restore_saved_sigmask();
return handled_sig;
}
static int kern_do_signal(struct pt_regs *regs)
{
struct k_sigaction ka_copy;
siginfo_t info;
sigset_t *oldset;
int sig, handled_sig = 0;
if (test_thread_flag(TIF_RESTORE_SIGMASK))
oldset = ¤t->saved_sigmask;
else
oldset = ¤t->blocked;
while ((sig = get_signal_to_deliver(&info, &ka_copy, regs, NULL)) > 0) {
handled_sig = 1;
if (!handle_signal(regs, sig, &ka_copy, &info, oldset)) {
if (test_thread_flag(TIF_RESTORE_SIGMASK))
clear_thread_flag(TIF_RESTORE_SIGMASK);
break;
}
}
if (!handled_sig && (PT_REGS_SYSCALL_NR(regs) >= 0)) {
switch (PT_REGS_SYSCALL_RET(regs)) {
case -ERESTARTNOHAND:
case -ERESTARTSYS:
case -ERESTARTNOINTR:
PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs);
PT_REGS_RESTART_SYSCALL(regs);
break;
case -ERESTART_RESTARTBLOCK:
PT_REGS_ORIG_SYSCALL(regs) = __NR_restart_syscall;
PT_REGS_RESTART_SYSCALL(regs);
break;
}
}
if (current->ptrace & PT_DTRACE)
current->thread.singlestep_syscall =
is_syscall(PT_REGS_IP(¤t->thread.regs));
if (!handled_sig && test_thread_flag(TIF_RESTORE_SIGMASK)) {
clear_thread_flag(TIF_RESTORE_SIGMASK);
sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
}
return handled_sig;
}
int sys_rt_sigreturn(struct pt_regs regs)
{
struct ucontext *uc = sp_to_uc(PT_REGS_SP(¤t->thread.regs));
void *fp;
int sig_size = _NSIG_WORDS * sizeof(unsigned long);
spin_lock_irq(¤t->sighand->siglock);
copy_from_user(¤t->blocked, &uc->uc_sigmask, sig_size);
sigdelsetmask(¤t->blocked, ~_BLOCKABLE);
recalc_sigpending();
spin_unlock_irq(¤t->sighand->siglock);
fp = (void *) (((unsigned long) uc) + sizeof(struct ucontext));
copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext,
&signal_frame_si.common.arch);
return(PT_REGS_SYSCALL_RET(¤t->thread.regs));
}
int sys_sigreturn(struct pt_regs regs)
{
void *sc = sp_to_sc(PT_REGS_SP(¤t->thread.regs));
void *mask = sp_to_mask(PT_REGS_SP(¤t->thread.regs));
int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
spin_lock_irq(¤t->sighand->siglock);
copy_from_user(¤t->blocked.sig[0], sc_sigmask(sc),
sizeof(current->blocked.sig[0]));
copy_from_user(¤t->blocked.sig[1], mask, sig_size);
sigdelsetmask(¤t->blocked, ~_BLOCKABLE);
recalc_sigpending();
spin_unlock_irq(¤t->sighand->siglock);
copy_sc_from_user(¤t->thread.regs, sc,
&signal_frame_sc.common.arch);
return(PT_REGS_SYSCALL_RET(¤t->thread.regs));
}
