2 * linux/arch/x86_64/kernel/signal.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs
7 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
8 * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes
9 * 2000-2002 x86-64 support by Andi Kleen
11 * $Id: signal.c,v 1.18 2001/10/17 22:30:37 ak Exp $
14 #include <linux/sched.h>
16 #include <linux/smp.h>
17 #include <linux/smp_lock.h>
18 #include <linux/kernel.h>
19 #include <linux/signal.h>
20 #include <linux/errno.h>
21 #include <linux/wait.h>
22 #include <linux/ptrace.h>
23 #include <linux/unistd.h>
24 #include <linux/stddef.h>
25 #include <linux/personality.h>
26 #include <linux/compiler.h>
27 #include <linux/suspend.h>
28 #include <asm/ucontext.h>
29 #include <asm/uaccess.h>
31 #include <asm/proto.h>
33 /* #define DEBUG_SIG 1 */
35 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
37 void ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
38 sigset_t *set, struct pt_regs * regs);
39 void ia32_setup_frame(int sig, struct k_sigaction *ka,
40 sigset_t *set, struct pt_regs * regs);
43 sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, struct pt_regs regs)
45 sigset_t saveset, newset;
47 /* XXX: Don't preclude handling different sized sigset_t's. */
48 if (sigsetsize != sizeof(sigset_t))
51 if (copy_from_user(&newset, unewset, sizeof(newset)))
53 sigdelsetmask(&newset, ~_BLOCKABLE);
55 spin_lock_irq(¤t->sighand->siglock);
56 saveset = current->blocked;
57 current->blocked = newset;
59 spin_unlock_irq(¤t->sighand->siglock);
61 printk("rt_sigsuspend savset(%lx) newset(%lx) regs(%p) rip(%lx)\n",
62 saveset, newset, ®s, regs.rip);
66 current->state = TASK_INTERRUPTIBLE;
68 if (do_signal(®s, &saveset))
74 sys_sigaltstack(const stack_t *uss, stack_t *uoss, struct pt_regs regs)
76 return do_sigaltstack(uss, uoss, regs.rsp);
81 * Do a signal return; undo the signal stack.
92 restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc, unsigned long *prax)
96 /* Always make any pending restarted system calls return -EINTR */
97 current_thread_info()->restart_block.fn = do_no_restart_syscall;
99 #define COPY(x) err |= __get_user(regs->x, &sc->x)
101 COPY(rdi); COPY(rsi); COPY(rbp); COPY(rsp); COPY(rbx);
102 COPY(rdx); COPY(rcx); COPY(rip);
113 unsigned int tmpflags;
114 err |= __get_user(tmpflags, &sc->eflags);
115 regs->eflags = (regs->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
116 regs->orig_rax = -1; /* disable syscall checks */
120 struct _fpstate * buf;
121 err |= __get_user(buf, &sc->fpstate);
124 if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
126 err |= restore_i387(buf);
130 err |= __get_user(*prax, &sc->rax);
137 asmlinkage long sys_rt_sigreturn(struct pt_regs regs)
139 struct rt_sigframe *frame = (struct rt_sigframe *)(regs.rsp - 8);
143 if (verify_area(VERIFY_READ, frame, sizeof(*frame))) {
146 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) {
150 sigdelsetmask(&set, ~_BLOCKABLE);
151 spin_lock_irq(¤t->sighand->siglock);
152 current->blocked = set;
154 spin_unlock_irq(¤t->sighand->siglock);
156 if (restore_sigcontext(®s, &frame->uc.uc_mcontext, &eax)) {
161 printk("%d sigreturn rip:%lx rsp:%lx frame:%p rax:%lx\n",current->pid,regs.rip,regs.rsp,frame,eax);
164 if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs.rsp) == -EFAULT)
170 signal_fault(®s,frame,"sigreturn");
175 * Set up a signal frame.
179 setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, unsigned long mask, struct task_struct *me)
183 err |= __put_user(0, &sc->gs);
184 err |= __put_user(0, &sc->fs);
186 err |= __put_user(regs->rdi, &sc->rdi);
187 err |= __put_user(regs->rsi, &sc->rsi);
188 err |= __put_user(regs->rbp, &sc->rbp);
189 err |= __put_user(regs->rsp, &sc->rsp);
190 err |= __put_user(regs->rbx, &sc->rbx);
191 err |= __put_user(regs->rdx, &sc->rdx);
192 err |= __put_user(regs->rcx, &sc->rcx);
193 err |= __put_user(regs->rax, &sc->rax);
194 err |= __put_user(regs->r8, &sc->r8);
195 err |= __put_user(regs->r9, &sc->r9);
196 err |= __put_user(regs->r10, &sc->r10);
197 err |= __put_user(regs->r11, &sc->r11);
198 err |= __put_user(regs->r12, &sc->r12);
199 err |= __put_user(regs->r13, &sc->r13);
200 err |= __put_user(regs->r14, &sc->r14);
201 err |= __put_user(regs->r15, &sc->r15);
202 err |= __put_user(me->thread.trap_no, &sc->trapno);
203 err |= __put_user(me->thread.error_code, &sc->err);
204 err |= __put_user(regs->rip, &sc->rip);
205 err |= __put_user(regs->eflags, &sc->eflags);
206 err |= __put_user(mask, &sc->oldmask);
207 err |= __put_user(me->thread.cr2, &sc->cr2);
213 * Determine which stack to use..
217 get_stack(struct k_sigaction *ka, struct pt_regs *regs, unsigned long size)
221 /* Default to using normal stack - redzone*/
222 rsp = regs->rsp - 128;
224 /* This is the X/Open sanctioned signal stack switching. */
225 /* RED-PEN: redzone on that stack? */
226 if (ka->sa.sa_flags & SA_ONSTACK) {
227 if (sas_ss_flags(rsp) == 0)
228 rsp = current->sas_ss_sp + current->sas_ss_size;
231 return (void *)round_down(rsp - size, 16);
234 static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
235 sigset_t *set, struct pt_regs * regs)
237 struct rt_sigframe *frame;
238 struct _fpstate *fp = NULL;
240 struct task_struct *me = current;
243 fp = get_stack(ka, regs, sizeof(struct _fpstate));
244 frame = (void *)round_down((u64)fp - sizeof(struct rt_sigframe), 16) - 8;
246 if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate))) {
250 if (save_i387(fp) < 0)
253 frame = get_stack(ka, regs, sizeof(struct rt_sigframe)) - 8;
256 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) {
260 if (ka->sa.sa_flags & SA_SIGINFO) {
261 err |= copy_siginfo_to_user(&frame->info, info);
267 /* Create the ucontext. */
268 err |= __put_user(0, &frame->uc.uc_flags);
269 err |= __put_user(0, &frame->uc.uc_link);
270 err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
271 err |= __put_user(sas_ss_flags(regs->rsp),
272 &frame->uc.uc_stack.ss_flags);
273 err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
274 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0], me);
275 err |= __put_user(fp, &frame->uc.uc_mcontext.fpstate);
276 if (sizeof(*set) == 16) {
277 __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
278 __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
280 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
283 /* Set up to return from userspace. If provided, use a stub
284 already in userspace. */
285 /* x86-64 should always use SA_RESTORER. */
286 if (ka->sa.sa_flags & SA_RESTORER) {
287 err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
289 printk("%s forgot to set SA_RESTORER for signal %d.\n", me->comm, sig);
298 printk("%d old rip %lx old rsp %lx old rax %lx\n", current->pid,regs->rip,regs->rsp,regs->rax);
301 /* Set up registers for signal handler */
303 struct exec_domain *ed = current_thread_info()->exec_domain;
304 if (unlikely(ed && ed->signal_invmap && sig < 32))
305 sig = ed->signal_invmap[sig];
308 /* In case the signal handler was declared without prototypes */
311 /* This also works for non SA_SIGINFO handlers because they expect the
312 next argument after the signal number on the stack. */
313 regs->rsi = (unsigned long)&frame->info;
314 regs->rdx = (unsigned long)&frame->uc;
315 regs->rip = (unsigned long) ka->sa.sa_handler;
317 regs->rsp = (unsigned long)frame;
320 regs->eflags &= ~TF_MASK;
323 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
324 current->comm, current->pid, frame, regs->rip, frame->pretcode);
331 ka->sa.sa_handler = SIG_DFL;
332 signal_fault(regs,frame,"signal deliver");
336 * OK, we're invoking a handler
340 handle_signal(unsigned long sig, siginfo_t *info, sigset_t *oldset,
341 struct pt_regs * regs)
343 struct k_sigaction *ka = ¤t->sighand->action[sig-1];
346 printk("handle_signal pid:%d sig:%lu rip:%lx rsp:%lx regs=%p\n", current->pid, sig,
347 regs->rip, regs->rsp, regs);
350 /* Are we from a system call? */
351 if (regs->orig_rax >= 0) {
352 /* If so, check system call restarting.. */
354 case -ERESTART_RESTARTBLOCK:
355 case -ERESTARTNOHAND:
360 if (!(ka->sa.sa_flags & SA_RESTART)) {
365 case -ERESTARTNOINTR:
366 regs->rax = regs->orig_rax;
371 #ifdef CONFIG_IA32_EMULATION
372 if (test_thread_flag(TIF_IA32)) {
373 if (ka->sa.sa_flags & SA_SIGINFO)
374 ia32_setup_rt_frame(sig, ka, info, oldset, regs);
376 ia32_setup_frame(sig, ka, oldset, regs);
379 setup_rt_frame(sig, ka, info, oldset, regs);
381 if (ka->sa.sa_flags & SA_ONESHOT)
382 ka->sa.sa_handler = SIG_DFL;
384 if (!(ka->sa.sa_flags & SA_NODEFER)) {
385 spin_lock_irq(¤t->sighand->siglock);
386 sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
387 sigaddset(¤t->blocked,sig);
389 spin_unlock_irq(¤t->sighand->siglock);
394 * Note that 'init' is a special process: it doesn't get signals it doesn't
395 * want to handle. Thus you cannot kill init even with a SIGKILL even by
398 int do_signal(struct pt_regs *regs, sigset_t *oldset)
404 * We want the common case to go fast, which
405 * is why we may in certain cases get here from
406 * kernel mode. Just return without doing anything
409 if ((regs->cs & 3) != 3) {
413 if (current->flags & PF_FREEZE) {
419 oldset = ¤t->blocked;
421 signr = get_signal_to_deliver(&info, regs, NULL);
423 /* Reenable any watchpoints before delivering the
424 * signal to user space. The processor register will
425 * have been cleared if the watchpoint triggered
428 if (current->thread.debugreg7)
429 asm volatile("movq %0,%%db7" : : "r" (current->thread.debugreg7));
431 /* Whee! Actually deliver the signal. */
432 handle_signal(signr, &info, oldset, regs);
437 /* Did we come from a system call? */
438 if (regs->orig_rax >= 0) {
439 /* Restart the system call - no handlers present */
440 long res = regs->rax;
441 if (res == -ERESTARTNOHAND ||
442 res == -ERESTARTSYS ||
443 res == -ERESTARTNOINTR) {
444 regs->rax = regs->orig_rax;
447 if (regs->rax == (unsigned long)-ERESTART_RESTARTBLOCK) {
448 regs->rax = __NR_restart_syscall;
455 void do_notify_resume(struct pt_regs *regs, sigset_t *oldset, __u32 thread_info_flags)
458 printk("do_notify_resume flags:%x rip:%lx rsp:%lx caller:%lx pending:%lx\n",
459 thread_info_flags, regs->rip, regs->rsp, __builtin_return_address(0),signal_pending(current));
462 /* Pending single-step? */
463 if (thread_info_flags & _TIF_SINGLESTEP) {
464 regs->eflags |= TF_MASK;
465 clear_thread_flag(TIF_SINGLESTEP);
468 /* deal with pending signal delivery */
469 if (thread_info_flags & _TIF_SIGPENDING)
470 do_signal(regs,oldset);
473 void signal_fault(struct pt_regs *regs, void *frame, char *where)
475 struct task_struct *me = current;
477 printk("%s[%d] bad frame in %s frame:%p rip:%lx rsp:%lx orax:%lx\n",
478 me->comm,me->pid,where,frame,regs->rip,regs->rsp,regs->orig_rax);
480 force_sig(SIGSEGV, me);