/*
* Architecture-specific signal handling support.
*
- * Copyright (C) 1999-2003 Hewlett-Packard Co
+ * Copyright (C) 1999-2004 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
*
* Derived from i386 and Alpha versions.
#endif
long
-ia64_rt_sigsuspend (sigset_t *uset, size_t sigsetsize, struct sigscratch *scr)
+ia64_rt_sigsuspend (sigset_t __user *uset, size_t sigsetsize, struct sigscratch *scr)
{
sigset_t oldset, set;
}
asmlinkage long
-sys_sigaltstack (const stack_t *uss, stack_t *uoss, long arg2, long arg3, long arg4,
- long arg5, long arg6, long arg7, long stack)
+sys_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, long arg2,
+ long arg3, long arg4, long arg5, long arg6, long arg7,
+ struct pt_regs regs)
{
- struct pt_regs *pt = (struct pt_regs *) &stack;
-
- return do_sigaltstack(uss, uoss, pt->r12);
+ return do_sigaltstack(uss, uoss, regs.r12);
}
static long
-restore_sigcontext (struct sigcontext *sc, struct sigscratch *scr)
+restore_sigcontext (struct sigcontext __user *sc, struct sigscratch *scr)
{
unsigned long ip, flags, nat, um, cfm;
long err;
}
int
-copy_siginfo_to_user (siginfo_t *to, siginfo_t *from)
+copy_siginfo_to_user (siginfo_t __user *to, siginfo_t *from)
{
if (!access_ok(VERIFY_WRITE, to, sizeof(siginfo_t)))
return -EFAULT;
ia64_rt_sigreturn (struct sigscratch *scr)
{
extern char ia64_strace_leave_kernel, ia64_leave_kernel;
- struct sigcontext *sc;
+ struct sigcontext __user *sc;
struct siginfo si;
sigset_t set;
long retval;
- sc = &((struct sigframe *) (scr->pt.r12 + 16))->sc;
+ sc = &((struct sigframe __user *) (scr->pt.r12 + 16))->sc;
/*
* When we return to the previously executing context, r8 and r10 have already
* could be corrupted.
*/
retval = (long) &ia64_leave_kernel;
- if (test_thread_flag(TIF_SYSCALL_TRACE))
+ if (test_thread_flag(TIF_SYSCALL_TRACE)
+ || test_thread_flag(TIF_SYSCALL_AUDIT))
/*
* strace expects to be notified after sigreturn returns even though the
* context to which we return may not be in the middle of a syscall.
* It is more difficult to avoid calling this function than to
* call it and ignore errors.
*/
- do_sigaltstack(&sc->sc_stack, 0, scr->pt.r12);
+ do_sigaltstack(&sc->sc_stack, NULL, scr->pt.r12);
return retval;
give_sigsegv:
* trampoline starts. Everything else is done at the user-level.
*/
static long
-setup_sigcontext (struct sigcontext *sc, sigset_t *mask, struct sigscratch *scr)
+setup_sigcontext (struct sigcontext __user *sc, sigset_t *mask, struct sigscratch *scr)
{
unsigned long flags = 0, ifs, cfm, nat;
long err;
if (on_sig_stack((unsigned long) sc))
flags |= IA64_SC_FLAG_ONSTACK;
- if ((ifs & (1UL << 63)) == 0) {
- /* if cr_ifs isn't valid, we got here through a syscall */
+ if ((ifs & (1UL << 63)) == 0)
+ /* if cr_ifs doesn't have the valid bit set, we got here through a syscall */
flags |= IA64_SC_FLAG_IN_SYSCALL;
- cfm = scr->ar_pfs & ((1UL << 38) - 1);
- } else
- cfm = ifs & ((1UL << 38) - 1);
+ cfm = ifs & ((1UL << 38) - 1);
ia64_flush_fph(current);
if ((current->thread.flags & IA64_THREAD_FPH_VALID)) {
flags |= IA64_SC_FLAG_FPH_VALID;
err |= __put_user(scr->pt.ar_ccv, &sc->sc_ar_ccv); /* ar.ccv */
err |= __put_user(scr->pt.b7, &sc->sc_br[7]); /* b7 */
err |= __put_user(scr->pt.r14, &sc->sc_gr[14]); /* r14 */
- err |= __copy_to_user(&scr->pt.ar_csd, &sc->sc_ar25, 2*8); /* ar.csd & ar.ssd */
+ err |= __copy_to_user(&sc->sc_ar25, &scr->pt.ar_csd, 2*8); /* ar.csd & ar.ssd */
err |= __copy_to_user(&sc->sc_gr[2], &scr->pt.r2, 2*8); /* r2-r3 */
err |= __copy_to_user(&sc->sc_gr[16], &scr->pt.r16, 16*8); /* r16-r31 */
}
return (bsp - current->sas_ss_sp < current->sas_ss_size);
}
+static long
+force_sigsegv_info (int sig, void __user *addr)
+{
+ unsigned long flags;
+ struct siginfo si;
+
+ if (sig == SIGSEGV) {
+ /*
+ * Acquiring siglock around the sa_handler-update is almost
+ * certainly overkill, but this isn't a
+ * performance-critical path and I'd rather play it safe
+ * here than having to debug a nasty race if and when
+ * something changes in kernel/signal.c that would make it
+ * no longer safe to modify sa_handler without holding the
+ * lock.
+ */
+ spin_lock_irqsave(¤t->sighand->siglock, flags);
+ current->sighand->action[sig - 1].sa.sa_handler = SIG_DFL;
+ spin_unlock_irqrestore(¤t->sighand->siglock, flags);
+ }
+ si.si_signo = SIGSEGV;
+ si.si_errno = 0;
+ si.si_code = SI_KERNEL;
+ si.si_pid = current->pid;
+ si.si_uid = current->uid;
+ si.si_addr = addr;
+ force_sig_info(SIGSEGV, &si, current);
+ return 0;
+}
+
static long
setup_frame (int sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *set,
struct sigscratch *scr)
{
extern char __kernel_sigtramp[];
unsigned long tramp_addr, new_rbs = 0;
- struct sigframe *frame;
- struct siginfo si;
+ struct sigframe __user *frame;
long err;
- frame = (void *) scr->pt.r12;
+ frame = (void __user *) scr->pt.r12;
tramp_addr = (unsigned long) __kernel_sigtramp;
if ((ka->sa.sa_flags & SA_ONSTACK) && sas_ss_flags((unsigned long) frame) == 0) {
- frame = (void *) ((current->sas_ss_sp + current->sas_ss_size)
- & ~(STACK_ALIGN - 1));
+ frame = (void __user *) ((current->sas_ss_sp + current->sas_ss_size)
+ & ~(STACK_ALIGN - 1));
/*
* We need to check for the register stack being on the signal stack
* separately, because it's switched separately (memory stack is switched
if (!rbs_on_sig_stack(scr->pt.ar_bspstore))
new_rbs = (current->sas_ss_sp + sizeof(long) - 1) & ~(sizeof(long) - 1);
}
- frame = (void *) frame - ((sizeof(*frame) + STACK_ALIGN - 1) & ~(STACK_ALIGN - 1));
+ frame = (void __user *) frame - ((sizeof(*frame) + STACK_ALIGN - 1) & ~(STACK_ALIGN - 1));
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
- goto give_sigsegv;
+ return force_sigsegv_info(sig, frame);
err = __put_user(sig, &frame->arg0);
err |= __put_user(&frame->info, &frame->arg1);
err |= __put_user(sas_ss_flags(scr->pt.r12), &frame->sc.sc_stack.ss_flags);
err |= setup_sigcontext(&frame->sc, set, scr);
- if (err)
- goto give_sigsegv;
+ if (unlikely(err))
+ return force_sigsegv_info(sig, frame);
scr->pt.r12 = (unsigned long) frame - 16; /* new stack pointer */
scr->pt.ar_fpsr = FPSR_DEFAULT; /* reset fpsr for signal handler */
current->comm, current->pid, sig, scr->pt.r12, frame->sc.sc_ip, frame->handler);
#endif
return 1;
-
- give_sigsegv:
- if (sig == SIGSEGV)
- ka->sa.sa_handler = SIG_DFL;
- si.si_signo = SIGSEGV;
- si.si_errno = 0;
- si.si_code = SI_KERNEL;
- si.si_pid = current->pid;
- si.si_uid = current->uid;
- si.si_addr = frame;
- force_sig_info(SIGSEGV, &si, current);
- return 0;
}
static long
if (!setup_frame(sig, ka, info, oldset, scr))
return 0;
- if (ka->sa.sa_flags & SA_ONESHOT)
- ka->sa.sa_handler = SIG_DFL;
-
if (!(ka->sa.sa_flags & SA_NODEFER)) {
spin_lock_irq(¤t->sighand->siglock);
{
long
ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
{
- struct k_sigaction *ka;
+ struct k_sigaction ka;
siginfo_t info;
long restart = in_syscall;
long errno = scr->pt.r8;
* need to push through a forced SIGSEGV.
*/
while (1) {
- int signr = get_signal_to_deliver(&info, &scr->pt, NULL);
+ int signr = get_signal_to_deliver(&info, &ka, &scr->pt, NULL);
/*
* get_signal_to_deliver() may have run a debugger (via notify_parent())
if (signr <= 0)
break;
- ka = ¤t->sighand->action[signr - 1];
-
if (unlikely(restart)) {
switch (errno) {
case ERESTART_RESTARTBLOCK:
break;
case ERESTARTSYS:
- if ((ka->sa.sa_flags & SA_RESTART) == 0) {
+ if ((ka.sa.sa_flags & SA_RESTART) == 0) {
scr->pt.r8 = ERR_CODE(EINTR);
/* note: scr->pt.r10 is already -1 */
break;
* Whee! Actually deliver the signal. If the delivery failed, we need to
* continue to iterate in this loop so we can deliver the SIGSEGV...
*/
- if (handle_signal(signr, ka, &info, oldset, scr))
+ if (handle_signal(signr, &ka, &info, oldset, scr))
return 1;
}
}
return 0;
}
+
+/* Set a delayed signal that was detected in MCA/INIT/NMI/PMI context where it
+ * could not be delivered. It is important that the target process is not
+ * allowed to do any more work in user space. Possible cases for the target
+ * process:
+ *
+ * - It is sleeping and will wake up soon. Store the data in the current task,
+ * the signal will be sent when the current task returns from the next
+ * interrupt.
+ *
+ * - It is running in user context. Store the data in the current task, the
+ * signal will be sent when the current task returns from the next interrupt.
+ *
+ * - It is running in kernel context on this or another cpu and will return to
+ * user context. Store the data in the target task, the signal will be sent
+ * to itself when the target task returns to user space.
+ *
+ * - It is running in kernel context on this cpu and will sleep before
+ * returning to user context. Because this is also the current task, the
+ * signal will not get delivered and the task could sleep indefinitely.
+ * Store the data in the idle task for this cpu, the signal will be sent
+ * after the idle task processes its next interrupt.
+ *
+ * To cover all cases, store the data in the target task, the current task and
+ * the idle task on this cpu. Whatever happens, the signal will be delivered
+ * to the target task before it can do any useful user space work. Multiple
+ * deliveries have no unwanted side effects.
+ *
+ * Note: This code is executed in MCA/INIT/NMI/PMI context, with interrupts
+ * disabled. It must not take any locks nor use kernel structures or services
+ * that require locks.
+ */
+
+/* To ensure that we get the right pid, check its start time. To avoid extra
+ * include files in thread_info.h, convert the task start_time to unsigned long,
+ * giving us a cycle time of > 580 years.
+ */
+static inline unsigned long
+start_time_ul(const struct task_struct *t)
+{
+ return t->start_time.tv_sec * NSEC_PER_SEC + t->start_time.tv_nsec;
+}
+
+void
+set_sigdelayed(pid_t pid, int signo, int code, void __user *addr)
+{
+ struct task_struct *t;
+ unsigned long start_time = 0;
+ int i;
+
+ for (i = 1; i <= 3; ++i) {
+ switch (i) {
+ case 1:
+ t = find_task_by_pid(pid);
+ if (t)
+ start_time = start_time_ul(t);
+ break;
+ case 2:
+ t = current;
+ break;
+ default:
+ t = idle_task(smp_processor_id());
+ break;
+ }
+
+ if (!t)
+ return;
+ t->thread_info->sigdelayed.signo = signo;
+ t->thread_info->sigdelayed.code = code;
+ t->thread_info->sigdelayed.addr = addr;
+ t->thread_info->sigdelayed.start_time = start_time;
+ t->thread_info->sigdelayed.pid = pid;
+ wmb();
+ set_tsk_thread_flag(t, TIF_SIGDELAYED);
+ }
+}
+
+/* Called from entry.S when it detects TIF_SIGDELAYED, a delayed signal that
+ * was detected in MCA/INIT/NMI/PMI context where it could not be delivered.
+ */
+
+void
+do_sigdelayed(void)
+{
+ struct siginfo siginfo;
+ pid_t pid;
+ struct task_struct *t;
+
+ clear_thread_flag(TIF_SIGDELAYED);
+ memset(&siginfo, 0, sizeof(siginfo));
+ siginfo.si_signo = current_thread_info()->sigdelayed.signo;
+ siginfo.si_code = current_thread_info()->sigdelayed.code;
+ siginfo.si_addr = current_thread_info()->sigdelayed.addr;
+ pid = current_thread_info()->sigdelayed.pid;
+ t = find_task_by_pid(pid);
+ if (!t)
+ return;
+ if (current_thread_info()->sigdelayed.start_time != start_time_ul(t))
+ return;
+ force_sig_info(siginfo.si_signo, &siginfo, t);
+}
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