2 * linux/arch/x86_64/ia32/ia32_signal.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
6 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
7 * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes
8 * 2000-12-* x86-64 compatibility mode signal handling by Andi Kleen
11 #include <linux/sched.h>
13 #include <linux/smp.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/wait.h>
17 #include <linux/unistd.h>
18 #include <linux/stddef.h>
19 #include <linux/personality.h>
20 #include <linux/compat.h>
21 #include <linux/binfmts.h>
22 #include <asm/ucontext.h>
23 #include <asm/uaccess.h>
24 #include <asm/fpu/internal.h>
25 #include <asm/fpu/signal.h>
26 #include <asm/ptrace.h>
27 #include <asm/ia32_unistd.h>
28 #include <asm/user32.h>
29 #include <uapi/asm/sigcontext.h>
30 #include <asm/proto.h>
32 #include <asm/sigframe.h>
33 #include <asm/sighandling.h>
34 #include <asm/sys_ia32.h>
38 * Do a signal return; undo the signal stack.
40 #define loadsegment_gs(v) load_gs_index(v)
41 #define loadsegment_fs(v) loadsegment(fs, v)
42 #define loadsegment_ds(v) loadsegment(ds, v)
43 #define loadsegment_es(v) loadsegment(es, v)
45 #define get_user_seg(seg) ({ unsigned int v; savesegment(seg, v); v; })
46 #define set_user_seg(seg, v) loadsegment_##seg(v)
49 get_user_ex(regs->x, &sc->x); \
52 #define GET_SEG(seg) ({ \
54 get_user_ex(tmp, &sc->seg); \
58 #define COPY_SEG_CPL3(seg) do { \
59 regs->seg = GET_SEG(seg) | 3; \
62 #define RELOAD_SEG(seg) { \
63 unsigned int pre = (seg) | 3; \
64 unsigned int cur = get_user_seg(seg); \
66 set_user_seg(seg, pre); \
69 static int ia32_restore_sigcontext(struct pt_regs *regs,
70 struct sigcontext_32 __user *sc)
72 unsigned int tmpflags, err = 0;
77 /* Always make any pending restarted system calls return -EINTR */
78 current->restart_block.fn = do_no_restart_syscall;
86 COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
87 COPY(dx); COPY(cx); COPY(ip); COPY(ax);
88 /* Don't touch extended registers */
93 get_user_ex(tmpflags, &sc->flags);
94 regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
95 /* disable syscall checks */
98 get_user_ex(tmp, &sc->fpstate);
99 buf = compat_ptr(tmp);
100 } get_user_catch(err);
103 * Reload fs and gs if they have changed in the signal
104 * handler. This does not handle long fs/gs base changes in
105 * the handler, but does not clobber them at least in the
113 err |= fpu__restore_sig(buf, 1);
120 asmlinkage long sys32_sigreturn(void)
122 struct pt_regs *regs = current_pt_regs();
123 struct sigframe_ia32 __user *frame = (struct sigframe_ia32 __user *)(regs->sp-8);
126 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
128 if (__get_user(set.sig[0], &frame->sc.oldmask)
129 || (_COMPAT_NSIG_WORDS > 1
130 && __copy_from_user((((char *) &set.sig) + 4),
132 sizeof(frame->extramask))))
135 set_current_blocked(&set);
137 if (ia32_restore_sigcontext(regs, &frame->sc))
142 signal_fault(regs, frame, "32bit sigreturn");
146 asmlinkage long sys32_rt_sigreturn(void)
148 struct pt_regs *regs = current_pt_regs();
149 struct rt_sigframe_ia32 __user *frame;
152 frame = (struct rt_sigframe_ia32 __user *)(regs->sp - 4);
154 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
156 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
159 set_current_blocked(&set);
161 if (ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext))
164 if (compat_restore_altstack(&frame->uc.uc_stack))
170 signal_fault(regs, frame, "32bit rt sigreturn");
175 * Set up a signal frame.
178 static int ia32_setup_sigcontext(struct sigcontext_32 __user *sc,
179 void __user *fpstate,
180 struct pt_regs *regs, unsigned int mask)
185 put_user_ex(get_user_seg(gs), (unsigned int __user *)&sc->gs);
186 put_user_ex(get_user_seg(fs), (unsigned int __user *)&sc->fs);
187 put_user_ex(get_user_seg(ds), (unsigned int __user *)&sc->ds);
188 put_user_ex(get_user_seg(es), (unsigned int __user *)&sc->es);
190 put_user_ex(regs->di, &sc->di);
191 put_user_ex(regs->si, &sc->si);
192 put_user_ex(regs->bp, &sc->bp);
193 put_user_ex(regs->sp, &sc->sp);
194 put_user_ex(regs->bx, &sc->bx);
195 put_user_ex(regs->dx, &sc->dx);
196 put_user_ex(regs->cx, &sc->cx);
197 put_user_ex(regs->ax, &sc->ax);
198 put_user_ex(current->thread.trap_nr, &sc->trapno);
199 put_user_ex(current->thread.error_code, &sc->err);
200 put_user_ex(regs->ip, &sc->ip);
201 put_user_ex(regs->cs, (unsigned int __user *)&sc->cs);
202 put_user_ex(regs->flags, &sc->flags);
203 put_user_ex(regs->sp, &sc->sp_at_signal);
204 put_user_ex(regs->ss, (unsigned int __user *)&sc->ss);
206 put_user_ex(ptr_to_compat(fpstate), &sc->fpstate);
208 /* non-iBCS2 extensions.. */
209 put_user_ex(mask, &sc->oldmask);
210 put_user_ex(current->thread.cr2, &sc->cr2);
211 } put_user_catch(err);
217 * Determine which stack to use..
219 static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
221 void __user **fpstate)
223 struct fpu *fpu = ¤t->thread.fpu;
226 /* Default to using normal stack */
229 /* This is the X/Open sanctioned signal stack switching. */
230 if (ksig->ka.sa.sa_flags & SA_ONSTACK)
231 sp = sigsp(sp, ksig);
232 /* This is the legacy signal stack switching. */
233 else if ((regs->ss & 0xffff) != __USER32_DS &&
234 !(ksig->ka.sa.sa_flags & SA_RESTORER) &&
235 ksig->ka.sa.sa_restorer)
236 sp = (unsigned long) ksig->ka.sa.sa_restorer;
238 if (fpu->fpstate_active) {
239 unsigned long fx_aligned, math_size;
241 sp = fpu__alloc_mathframe(sp, 1, &fx_aligned, &math_size);
242 *fpstate = (struct _fpstate_32 __user *) sp;
243 if (copy_fpstate_to_sigframe(*fpstate, (void __user *)fx_aligned,
245 return (void __user *) -1L;
249 /* Align the stack pointer according to the i386 ABI,
250 * i.e. so that on function entry ((sp + 4) & 15) == 0. */
251 sp = ((sp + 4) & -16ul) - 4;
252 return (void __user *) sp;
255 int ia32_setup_frame(int sig, struct ksignal *ksig,
256 compat_sigset_t *set, struct pt_regs *regs)
258 struct sigframe_ia32 __user *frame;
259 void __user *restorer;
261 void __user *fpstate = NULL;
263 /* copy_to_user optimizes that into a single 8 byte store */
264 static const struct {
268 } __attribute__((packed)) code = {
269 0xb858, /* popl %eax ; movl $...,%eax */
271 0x80cd, /* int $0x80 */
274 frame = get_sigframe(ksig, regs, sizeof(*frame), &fpstate);
276 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
279 if (__put_user(sig, &frame->sig))
282 if (ia32_setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]))
285 if (_COMPAT_NSIG_WORDS > 1) {
286 if (__copy_to_user(frame->extramask, &set->sig[1],
287 sizeof(frame->extramask)))
291 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
292 restorer = ksig->ka.sa.sa_restorer;
294 /* Return stub is in 32bit vsyscall page */
295 if (current->mm->context.vdso)
296 restorer = current->mm->context.vdso +
297 vdso_image_32.sym___kernel_sigreturn;
299 restorer = &frame->retcode;
303 put_user_ex(ptr_to_compat(restorer), &frame->pretcode);
306 * These are actually not used anymore, but left because some
307 * gdb versions depend on them as a marker.
309 put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode);
310 } put_user_catch(err);
315 /* Set up registers for signal handler */
316 regs->sp = (unsigned long) frame;
317 regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
319 /* Make -mregparm=3 work */
324 loadsegment(ds, __USER32_DS);
325 loadsegment(es, __USER32_DS);
327 regs->cs = __USER32_CS;
328 regs->ss = __USER32_DS;
333 int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
334 compat_sigset_t *set, struct pt_regs *regs)
336 struct rt_sigframe_ia32 __user *frame;
337 void __user *restorer;
339 void __user *fpstate = NULL;
341 /* __copy_to_user optimizes that into a single 8 byte store */
342 static const struct {
347 } __attribute__((packed)) code = {
349 __NR_ia32_rt_sigreturn,
354 frame = get_sigframe(ksig, regs, sizeof(*frame), &fpstate);
356 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
360 put_user_ex(sig, &frame->sig);
361 put_user_ex(ptr_to_compat(&frame->info), &frame->pinfo);
362 put_user_ex(ptr_to_compat(&frame->uc), &frame->puc);
364 /* Create the ucontext. */
365 if (boot_cpu_has(X86_FEATURE_XSAVE))
366 put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags);
368 put_user_ex(0, &frame->uc.uc_flags);
369 put_user_ex(0, &frame->uc.uc_link);
370 compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp);
372 if (ksig->ka.sa.sa_flags & SA_RESTORER)
373 restorer = ksig->ka.sa.sa_restorer;
375 restorer = current->mm->context.vdso +
376 vdso_image_32.sym___kernel_rt_sigreturn;
377 put_user_ex(ptr_to_compat(restorer), &frame->pretcode);
380 * Not actually used anymore, but left because some gdb
383 put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode);
384 } put_user_catch(err);
386 err |= __copy_siginfo_to_user32(&frame->info, &ksig->info, false);
387 err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
389 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
394 /* Set up registers for signal handler */
395 regs->sp = (unsigned long) frame;
396 regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
398 /* Make -mregparm=3 work */
400 regs->dx = (unsigned long) &frame->info;
401 regs->cx = (unsigned long) &frame->uc;
403 loadsegment(ds, __USER32_DS);
404 loadsegment(es, __USER32_DS);
406 regs->cs = __USER32_CS;
407 regs->ss = __USER32_DS;