Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Copyright (C) 1991, 1992 Linus Torvalds |
3 | * | |
4 | * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson | |
5 | * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes | |
6 | */ | |
7e907f48 | 7 | #include <linux/list.h> |
1da177e4 | 8 | |
7e907f48 IM |
9 | #include <linux/personality.h> |
10 | #include <linux/binfmts.h> | |
11 | #include <linux/suspend.h> | |
1da177e4 | 12 | #include <linux/kernel.h> |
7e907f48 | 13 | #include <linux/ptrace.h> |
1da177e4 | 14 | #include <linux/signal.h> |
7e907f48 IM |
15 | #include <linux/stddef.h> |
16 | #include <linux/unistd.h> | |
1da177e4 | 17 | #include <linux/errno.h> |
7e907f48 | 18 | #include <linux/sched.h> |
1da177e4 | 19 | #include <linux/wait.h> |
36a03308 | 20 | #include <linux/tracehook.h> |
1da177e4 | 21 | #include <linux/elf.h> |
7e907f48 IM |
22 | #include <linux/smp.h> |
23 | #include <linux/mm.h> | |
24 | ||
1da177e4 LT |
25 | #include <asm/processor.h> |
26 | #include <asm/ucontext.h> | |
27 | #include <asm/uaccess.h> | |
28 | #include <asm/i387.h> | |
6c3652ef | 29 | #include <asm/vdso.h> |
bb57925f | 30 | #include <asm/syscall.h> |
bbc1f698 | 31 | #include <asm/syscalls.h> |
7e907f48 | 32 | |
123a6347 | 33 | #include "sigframe.h" |
1da177e4 | 34 | |
1da177e4 LT |
35 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) |
36 | ||
1a176803 HH |
37 | #define __FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \ |
38 | X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \ | |
39 | X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \ | |
40 | X86_EFLAGS_CF) | |
41 | ||
42 | #ifdef CONFIG_X86_32 | |
43 | # define FIX_EFLAGS (__FIX_EFLAGS | X86_EFLAGS_RF) | |
44 | #else | |
45 | # define FIX_EFLAGS __FIX_EFLAGS | |
46 | #endif | |
47 | ||
4a612048 HS |
48 | static const struct { |
49 | u16 poplmovl; | |
50 | u32 val; | |
51 | u16 int80; | |
52 | } __attribute__((packed)) retcode = { | |
53 | 0xb858, /* popl %eax; movl $..., %eax */ | |
54 | __NR_sigreturn, | |
55 | 0x80cd, /* int $0x80 */ | |
56 | }; | |
57 | ||
58 | static const struct { | |
59 | u8 movl; | |
60 | u32 val; | |
61 | u16 int80; | |
62 | u8 pad; | |
63 | } __attribute__((packed)) rt_retcode = { | |
64 | 0xb8, /* movl $..., %eax */ | |
65 | __NR_rt_sigreturn, | |
66 | 0x80cd, /* int $0x80 */ | |
67 | 0 | |
68 | }; | |
69 | ||
1da177e4 LT |
70 | /* |
71 | * Atomically swap in the new signal mask, and wait for a signal. | |
72 | */ | |
73 | asmlinkage int | |
74 | sys_sigsuspend(int history0, int history1, old_sigset_t mask) | |
75 | { | |
1da177e4 LT |
76 | mask &= _BLOCKABLE; |
77 | spin_lock_irq(¤t->sighand->siglock); | |
283828f3 | 78 | current->saved_sigmask = current->blocked; |
1da177e4 LT |
79 | siginitset(¤t->blocked, mask); |
80 | recalc_sigpending(); | |
81 | spin_unlock_irq(¤t->sighand->siglock); | |
82 | ||
283828f3 DH |
83 | current->state = TASK_INTERRUPTIBLE; |
84 | schedule(); | |
5a8da0ea | 85 | set_restore_sigmask(); |
7e907f48 | 86 | |
283828f3 | 87 | return -ERESTARTNOHAND; |
1da177e4 LT |
88 | } |
89 | ||
7e907f48 | 90 | asmlinkage int |
1da177e4 LT |
91 | sys_sigaction(int sig, const struct old_sigaction __user *act, |
92 | struct old_sigaction __user *oact) | |
93 | { | |
94 | struct k_sigaction new_ka, old_ka; | |
95 | int ret; | |
96 | ||
97 | if (act) { | |
98 | old_sigset_t mask; | |
7e907f48 | 99 | |
1da177e4 LT |
100 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || |
101 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
102 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | |
103 | return -EFAULT; | |
7e907f48 | 104 | |
1da177e4 LT |
105 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); |
106 | __get_user(mask, &act->sa_mask); | |
107 | siginitset(&new_ka.sa.sa_mask, mask); | |
108 | } | |
109 | ||
110 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
111 | ||
112 | if (!ret && oact) { | |
113 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
114 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
115 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | |
116 | return -EFAULT; | |
7e907f48 | 117 | |
1da177e4 LT |
118 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); |
119 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
120 | } | |
121 | ||
122 | return ret; | |
123 | } | |
124 | ||
7e907f48 | 125 | asmlinkage int sys_sigaltstack(unsigned long bx) |
1da177e4 | 126 | { |
7e907f48 IM |
127 | /* |
128 | * This is needed to make gcc realize it doesn't own the | |
129 | * "struct pt_regs" | |
130 | */ | |
65ea5b03 PA |
131 | struct pt_regs *regs = (struct pt_regs *)&bx; |
132 | const stack_t __user *uss = (const stack_t __user *)bx; | |
133 | stack_t __user *uoss = (stack_t __user *)regs->cx; | |
1da177e4 | 134 | |
65ea5b03 | 135 | return do_sigaltstack(uss, uoss, regs->sp); |
1da177e4 LT |
136 | } |
137 | ||
a2e8d3dc HS |
138 | #define COPY(x) { \ |
139 | err |= __get_user(regs->x, &sc->x); \ | |
140 | } | |
141 | ||
142 | #define COPY_SEG(seg) { \ | |
143 | unsigned short tmp; \ | |
144 | err |= __get_user(tmp, &sc->seg); \ | |
145 | regs->seg = tmp; \ | |
146 | } | |
147 | ||
148 | #define COPY_SEG_STRICT(seg) { \ | |
149 | unsigned short tmp; \ | |
150 | err |= __get_user(tmp, &sc->seg); \ | |
151 | regs->seg = tmp | 3; \ | |
152 | } | |
153 | ||
154 | #define GET_SEG(seg) { \ | |
155 | unsigned short tmp; \ | |
156 | err |= __get_user(tmp, &sc->seg); \ | |
157 | loadsegment(seg, tmp); \ | |
158 | } | |
1da177e4 LT |
159 | |
160 | /* | |
161 | * Do a signal return; undo the signal stack. | |
162 | */ | |
1da177e4 | 163 | static int |
866bc13f HH |
164 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, |
165 | unsigned long *pax) | |
1da177e4 | 166 | { |
69e13ad5 HS |
167 | void __user *buf; |
168 | unsigned int tmpflags; | |
1da177e4 LT |
169 | unsigned int err = 0; |
170 | ||
171 | /* Always make any pending restarted system calls return -EINTR */ | |
172 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
173 | ||
709110bd | 174 | #ifdef CONFIG_X86_32 |
464d1a78 JF |
175 | GET_SEG(gs); |
176 | COPY_SEG(fs); | |
1da177e4 LT |
177 | COPY_SEG(es); |
178 | COPY_SEG(ds); | |
709110bd HS |
179 | #endif /* CONFIG_X86_32 */ |
180 | ||
ac66f3fd HH |
181 | COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); |
182 | COPY(dx); COPY(cx); COPY(ip); | |
709110bd HS |
183 | |
184 | #ifdef CONFIG_X86_64 | |
185 | COPY(r8); | |
186 | COPY(r9); | |
187 | COPY(r10); | |
188 | COPY(r11); | |
189 | COPY(r12); | |
190 | COPY(r13); | |
191 | COPY(r14); | |
192 | COPY(r15); | |
193 | #endif /* CONFIG_X86_64 */ | |
194 | ||
195 | #ifdef CONFIG_X86_32 | |
1da177e4 LT |
196 | COPY_SEG_STRICT(cs); |
197 | COPY_SEG_STRICT(ss); | |
709110bd HS |
198 | #else /* !CONFIG_X86_32 */ |
199 | /* Kernel saves and restores only the CS segment register on signals, | |
200 | * which is the bare minimum needed to allow mixed 32/64-bit code. | |
201 | * App's signal handler can save/restore other segments if needed. */ | |
202 | COPY_SEG_STRICT(cs); | |
203 | #endif /* CONFIG_X86_32 */ | |
7e907f48 | 204 | |
69e13ad5 HS |
205 | err |= __get_user(tmpflags, &sc->flags); |
206 | regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
207 | regs->orig_ax = -1; /* disable syscall checks */ | |
7e907f48 | 208 | |
69e13ad5 HS |
209 | err |= __get_user(buf, &sc->fpstate); |
210 | err |= restore_i387_xstate(buf); | |
1da177e4 | 211 | |
866bc13f | 212 | err |= __get_user(*pax, &sc->ax); |
1da177e4 | 213 | return err; |
1da177e4 LT |
214 | } |
215 | ||
866bc13f | 216 | asmlinkage unsigned long sys_sigreturn(unsigned long __unused) |
1da177e4 | 217 | { |
7e907f48 IM |
218 | struct sigframe __user *frame; |
219 | struct pt_regs *regs; | |
866bc13f | 220 | unsigned long ax; |
7e907f48 IM |
221 | sigset_t set; |
222 | ||
223 | regs = (struct pt_regs *) &__unused; | |
224 | frame = (struct sigframe __user *)(regs->sp - 8); | |
1da177e4 LT |
225 | |
226 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
227 | goto badframe; | |
7e907f48 | 228 | if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1 |
1da177e4 LT |
229 | && __copy_from_user(&set.sig[1], &frame->extramask, |
230 | sizeof(frame->extramask)))) | |
231 | goto badframe; | |
232 | ||
233 | sigdelsetmask(&set, ~_BLOCKABLE); | |
234 | spin_lock_irq(¤t->sighand->siglock); | |
235 | current->blocked = set; | |
236 | recalc_sigpending(); | |
237 | spin_unlock_irq(¤t->sighand->siglock); | |
7e907f48 | 238 | |
65ea5b03 | 239 | if (restore_sigcontext(regs, &frame->sc, &ax)) |
1da177e4 | 240 | goto badframe; |
65ea5b03 | 241 | return ax; |
1da177e4 LT |
242 | |
243 | badframe: | |
03252919 | 244 | if (show_unhandled_signals && printk_ratelimit()) { |
1181f8b5 | 245 | printk("%s%s[%d] bad frame in sigreturn frame:" |
97b44ae6 | 246 | "%p ip:%lx sp:%lx oeax:%lx", |
19c5870c | 247 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
65ea5b03 PA |
248 | current->comm, task_pid_nr(current), frame, regs->ip, |
249 | regs->sp, regs->orig_ax); | |
03252919 | 250 | print_vma_addr(" in ", regs->ip); |
97b44ae6 | 251 | printk(KERN_CONT "\n"); |
03252919 | 252 | } |
abd4f750 | 253 | |
1da177e4 | 254 | force_sig(SIGSEGV, current); |
7e907f48 | 255 | |
1da177e4 | 256 | return 0; |
7e907f48 | 257 | } |
1da177e4 | 258 | |
e6babb6b | 259 | static long do_rt_sigreturn(struct pt_regs *regs) |
1da177e4 | 260 | { |
2d19c458 | 261 | struct rt_sigframe __user *frame; |
866bc13f | 262 | unsigned long ax; |
1da177e4 | 263 | sigset_t set; |
1da177e4 | 264 | |
2d19c458 | 265 | frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); |
1da177e4 LT |
266 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
267 | goto badframe; | |
268 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
269 | goto badframe; | |
270 | ||
271 | sigdelsetmask(&set, ~_BLOCKABLE); | |
272 | spin_lock_irq(¤t->sighand->siglock); | |
273 | current->blocked = set; | |
274 | recalc_sigpending(); | |
275 | spin_unlock_irq(¤t->sighand->siglock); | |
7e907f48 | 276 | |
65ea5b03 | 277 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) |
1da177e4 LT |
278 | goto badframe; |
279 | ||
65ea5b03 | 280 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT) |
1da177e4 LT |
281 | goto badframe; |
282 | ||
65ea5b03 | 283 | return ax; |
1da177e4 LT |
284 | |
285 | badframe: | |
e6babb6b | 286 | signal_fault(regs, frame, "rt_sigreturn"); |
1da177e4 | 287 | return 0; |
7e907f48 | 288 | } |
1da177e4 | 289 | |
e6babb6b HS |
290 | asmlinkage int sys_rt_sigreturn(unsigned long __unused) |
291 | { | |
292 | struct pt_regs *regs = (struct pt_regs *)&__unused; | |
293 | ||
294 | return do_rt_sigreturn(regs); | |
295 | } | |
296 | ||
1da177e4 LT |
297 | /* |
298 | * Set up a signal frame. | |
299 | */ | |
1da177e4 | 300 | static int |
ab513701 | 301 | setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, |
1da177e4 LT |
302 | struct pt_regs *regs, unsigned long mask) |
303 | { | |
15002fa9 | 304 | int err = 0; |
1da177e4 | 305 | |
15002fa9 HS |
306 | #ifdef CONFIG_X86_32 |
307 | { | |
308 | unsigned int tmp; | |
1da177e4 | 309 | |
15002fa9 HS |
310 | savesegment(gs, tmp); |
311 | err |= __put_user(tmp, (unsigned int __user *)&sc->gs); | |
312 | } | |
313 | err |= __put_user(regs->fs, (unsigned int __user *)&sc->fs); | |
65ea5b03 PA |
314 | err |= __put_user(regs->es, (unsigned int __user *)&sc->es); |
315 | err |= __put_user(regs->ds, (unsigned int __user *)&sc->ds); | |
15002fa9 HS |
316 | #endif /* CONFIG_X86_32 */ |
317 | ||
742fa54a PA |
318 | err |= __put_user(regs->di, &sc->di); |
319 | err |= __put_user(regs->si, &sc->si); | |
320 | err |= __put_user(regs->bp, &sc->bp); | |
321 | err |= __put_user(regs->sp, &sc->sp); | |
322 | err |= __put_user(regs->bx, &sc->bx); | |
323 | err |= __put_user(regs->dx, &sc->dx); | |
324 | err |= __put_user(regs->cx, &sc->cx); | |
325 | err |= __put_user(regs->ax, &sc->ax); | |
15002fa9 HS |
326 | #ifdef CONFIG_X86_64 |
327 | err |= __put_user(regs->r8, &sc->r8); | |
328 | err |= __put_user(regs->r9, &sc->r9); | |
329 | err |= __put_user(regs->r10, &sc->r10); | |
330 | err |= __put_user(regs->r11, &sc->r11); | |
331 | err |= __put_user(regs->r12, &sc->r12); | |
332 | err |= __put_user(regs->r13, &sc->r13); | |
333 | err |= __put_user(regs->r14, &sc->r14); | |
334 | err |= __put_user(regs->r15, &sc->r15); | |
335 | #endif /* CONFIG_X86_64 */ | |
336 | ||
1da177e4 LT |
337 | err |= __put_user(current->thread.trap_no, &sc->trapno); |
338 | err |= __put_user(current->thread.error_code, &sc->err); | |
742fa54a | 339 | err |= __put_user(regs->ip, &sc->ip); |
15002fa9 | 340 | #ifdef CONFIG_X86_32 |
65ea5b03 | 341 | err |= __put_user(regs->cs, (unsigned int __user *)&sc->cs); |
742fa54a PA |
342 | err |= __put_user(regs->flags, &sc->flags); |
343 | err |= __put_user(regs->sp, &sc->sp_at_signal); | |
65ea5b03 | 344 | err |= __put_user(regs->ss, (unsigned int __user *)&sc->ss); |
15002fa9 HS |
345 | #else /* !CONFIG_X86_32 */ |
346 | err |= __put_user(regs->flags, &sc->flags); | |
347 | err |= __put_user(regs->cs, &sc->cs); | |
348 | err |= __put_user(0, &sc->gs); | |
349 | err |= __put_user(0, &sc->fs); | |
350 | #endif /* CONFIG_X86_32 */ | |
1da177e4 | 351 | |
4b33669e | 352 | err |= __put_user(fpstate, &sc->fpstate); |
1da177e4 LT |
353 | |
354 | /* non-iBCS2 extensions.. */ | |
355 | err |= __put_user(mask, &sc->oldmask); | |
356 | err |= __put_user(current->thread.cr2, &sc->cr2); | |
357 | ||
358 | return err; | |
359 | } | |
360 | ||
361 | /* | |
362 | * Determine which stack to use.. | |
363 | */ | |
364 | static inline void __user * | |
3c1c7f10 | 365 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, |
ab513701 | 366 | void **fpstate) |
1da177e4 | 367 | { |
65ea5b03 | 368 | unsigned long sp; |
1da177e4 LT |
369 | |
370 | /* Default to using normal stack */ | |
65ea5b03 | 371 | sp = regs->sp; |
1da177e4 | 372 | |
83bd0102 RM |
373 | /* |
374 | * If we are on the alternate signal stack and would overflow it, don't. | |
375 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
376 | */ | |
65ea5b03 | 377 | if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size))) |
83bd0102 RM |
378 | return (void __user *) -1L; |
379 | ||
1da177e4 LT |
380 | /* This is the X/Open sanctioned signal stack switching. */ |
381 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
65ea5b03 PA |
382 | if (sas_ss_flags(sp) == 0) |
383 | sp = current->sas_ss_sp + current->sas_ss_size; | |
7e907f48 IM |
384 | } else { |
385 | /* This is the legacy signal stack switching. */ | |
386 | if ((regs->ss & 0xffff) != __USER_DS && | |
387 | !(ka->sa.sa_flags & SA_RESTORER) && | |
388 | ka->sa.sa_restorer) | |
389 | sp = (unsigned long) ka->sa.sa_restorer; | |
1da177e4 LT |
390 | } |
391 | ||
3c1c7f10 SS |
392 | if (used_math()) { |
393 | sp = sp - sig_xstate_size; | |
394 | *fpstate = (struct _fpstate *) sp; | |
4b33669e HS |
395 | if (save_i387_xstate(*fpstate) < 0) |
396 | return (void __user *)-1L; | |
3c1c7f10 SS |
397 | } |
398 | ||
65ea5b03 | 399 | sp -= frame_size; |
7e907f48 IM |
400 | /* |
401 | * Align the stack pointer according to the i386 ABI, | |
402 | * i.e. so that on function entry ((sp + 4) & 15) == 0. | |
403 | */ | |
65ea5b03 | 404 | sp = ((sp + 4) & -16ul) - 4; |
7e907f48 | 405 | |
65ea5b03 | 406 | return (void __user *) sp; |
1da177e4 LT |
407 | } |
408 | ||
7e907f48 | 409 | static int |
1d13024e HS |
410 | __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, |
411 | struct pt_regs *regs) | |
1da177e4 | 412 | { |
1da177e4 | 413 | struct sigframe __user *frame; |
7e907f48 | 414 | void __user *restorer; |
1da177e4 | 415 | int err = 0; |
ab513701 | 416 | void __user *fpstate = NULL; |
1da177e4 | 417 | |
3c1c7f10 | 418 | frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
419 | |
420 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 421 | return -EFAULT; |
1da177e4 | 422 | |
2ba48e16 | 423 | if (__put_user(sig, &frame->sig)) |
3d0aedd9 | 424 | return -EFAULT; |
1da177e4 | 425 | |
2ba48e16 | 426 | if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0])) |
3d0aedd9 | 427 | return -EFAULT; |
1da177e4 LT |
428 | |
429 | if (_NSIG_WORDS > 1) { | |
2ba48e16 HS |
430 | if (__copy_to_user(&frame->extramask, &set->sig[1], |
431 | sizeof(frame->extramask))) | |
3d0aedd9 | 432 | return -EFAULT; |
1da177e4 LT |
433 | } |
434 | ||
1a3e4ca4 | 435 | if (current->mm->context.vdso) |
6c3652ef | 436 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn); |
9fbbd4dd | 437 | else |
ade1af77 | 438 | restorer = &frame->retcode; |
1da177e4 LT |
439 | if (ka->sa.sa_flags & SA_RESTORER) |
440 | restorer = ka->sa.sa_restorer; | |
441 | ||
442 | /* Set up to return from userspace. */ | |
443 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 444 | |
1da177e4 | 445 | /* |
7e907f48 | 446 | * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 |
1da177e4 LT |
447 | * |
448 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
449 | * reasons and because gdb uses it as a signature to notice | |
450 | * signal handler stack frames. | |
451 | */ | |
4a612048 | 452 | err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode); |
1da177e4 LT |
453 | |
454 | if (err) | |
3d0aedd9 | 455 | return -EFAULT; |
1da177e4 LT |
456 | |
457 | /* Set up registers for signal handler */ | |
7e907f48 IM |
458 | regs->sp = (unsigned long)frame; |
459 | regs->ip = (unsigned long)ka->sa.sa_handler; | |
460 | regs->ax = (unsigned long)sig; | |
92bc2056 HH |
461 | regs->dx = 0; |
462 | regs->cx = 0; | |
1da177e4 | 463 | |
65ea5b03 PA |
464 | regs->ds = __USER_DS; |
465 | regs->es = __USER_DS; | |
466 | regs->ss = __USER_DS; | |
467 | regs->cs = __USER_CS; | |
1da177e4 | 468 | |
283828f3 | 469 | return 0; |
1da177e4 LT |
470 | } |
471 | ||
1d13024e HS |
472 | static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
473 | sigset_t *set, struct pt_regs *regs) | |
1da177e4 | 474 | { |
1da177e4 | 475 | struct rt_sigframe __user *frame; |
7e907f48 | 476 | void __user *restorer; |
1da177e4 | 477 | int err = 0; |
ab513701 | 478 | void __user *fpstate = NULL; |
1da177e4 | 479 | |
3c1c7f10 | 480 | frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
481 | |
482 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 483 | return -EFAULT; |
1da177e4 | 484 | |
13ad7725 | 485 | err |= __put_user(sig, &frame->sig); |
1da177e4 LT |
486 | err |= __put_user(&frame->info, &frame->pinfo); |
487 | err |= __put_user(&frame->uc, &frame->puc); | |
488 | err |= copy_siginfo_to_user(&frame->info, info); | |
489 | if (err) | |
3d0aedd9 | 490 | return -EFAULT; |
1da177e4 LT |
491 | |
492 | /* Create the ucontext. */ | |
c37b5efe SS |
493 | if (cpu_has_xsave) |
494 | err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags); | |
495 | else | |
496 | err |= __put_user(0, &frame->uc.uc_flags); | |
1da177e4 LT |
497 | err |= __put_user(0, &frame->uc.uc_link); |
498 | err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
65ea5b03 | 499 | err |= __put_user(sas_ss_flags(regs->sp), |
1da177e4 LT |
500 | &frame->uc.uc_stack.ss_flags); |
501 | err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
3c1c7f10 | 502 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
7e907f48 | 503 | regs, set->sig[0]); |
1da177e4 LT |
504 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); |
505 | if (err) | |
3d0aedd9 | 506 | return -EFAULT; |
1da177e4 LT |
507 | |
508 | /* Set up to return from userspace. */ | |
6c3652ef | 509 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn); |
1da177e4 LT |
510 | if (ka->sa.sa_flags & SA_RESTORER) |
511 | restorer = ka->sa.sa_restorer; | |
512 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 513 | |
1da177e4 | 514 | /* |
7e907f48 | 515 | * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 |
1da177e4 LT |
516 | * |
517 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
518 | * reasons and because gdb uses it as a signature to notice | |
519 | * signal handler stack frames. | |
520 | */ | |
4a612048 | 521 | err |= __put_user(*((u64 *)&rt_retcode), (u64 *)frame->retcode); |
1da177e4 LT |
522 | |
523 | if (err) | |
3d0aedd9 | 524 | return -EFAULT; |
1da177e4 LT |
525 | |
526 | /* Set up registers for signal handler */ | |
7e907f48 IM |
527 | regs->sp = (unsigned long)frame; |
528 | regs->ip = (unsigned long)ka->sa.sa_handler; | |
13ad7725 | 529 | regs->ax = (unsigned long)sig; |
7e907f48 IM |
530 | regs->dx = (unsigned long)&frame->info; |
531 | regs->cx = (unsigned long)&frame->uc; | |
1da177e4 | 532 | |
65ea5b03 PA |
533 | regs->ds = __USER_DS; |
534 | regs->es = __USER_DS; | |
535 | regs->ss = __USER_DS; | |
536 | regs->cs = __USER_CS; | |
1da177e4 | 537 | |
283828f3 | 538 | return 0; |
1da177e4 LT |
539 | } |
540 | ||
541 | /* | |
7e907f48 IM |
542 | * OK, we're invoking a handler: |
543 | */ | |
8d8c13bd HS |
544 | static int signr_convert(int sig) |
545 | { | |
96bf84b7 | 546 | #ifdef CONFIG_X86_32 |
8d8c13bd HS |
547 | struct thread_info *info = current_thread_info(); |
548 | ||
549 | if (info->exec_domain && info->exec_domain->signal_invmap && sig < 32) | |
550 | return info->exec_domain->signal_invmap[sig]; | |
96bf84b7 | 551 | #endif /* CONFIG_X86_32 */ |
8d8c13bd HS |
552 | return sig; |
553 | } | |
554 | ||
cabf5035 HS |
555 | #ifdef CONFIG_X86_32 |
556 | ||
455edbc4 | 557 | #define is_ia32 1 |
4694d239 HS |
558 | #define ia32_setup_frame __setup_frame |
559 | #define ia32_setup_rt_frame __setup_rt_frame | |
455edbc4 | 560 | |
cabf5035 HS |
561 | #else /* !CONFIG_X86_32 */ |
562 | ||
563 | #ifdef CONFIG_IA32_EMULATION | |
564 | #define is_ia32 test_thread_flag(TIF_IA32) | |
565 | #else /* !CONFIG_IA32_EMULATION */ | |
566 | #define is_ia32 0 | |
567 | #endif /* CONFIG_IA32_EMULATION */ | |
568 | ||
569 | #endif /* CONFIG_X86_32 */ | |
570 | ||
1d13024e HS |
571 | static int |
572 | setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
573 | sigset_t *set, struct pt_regs *regs) | |
574 | { | |
8d8c13bd | 575 | int usig = signr_convert(sig); |
1d13024e HS |
576 | int ret; |
577 | ||
578 | /* Set up the stack frame */ | |
455edbc4 HS |
579 | if (is_ia32) { |
580 | if (ka->sa.sa_flags & SA_SIGINFO) | |
4694d239 | 581 | ret = ia32_setup_rt_frame(usig, ka, info, set, regs); |
455edbc4 | 582 | else |
4694d239 | 583 | ret = ia32_setup_frame(usig, ka, set, regs); |
455edbc4 HS |
584 | } else |
585 | ret = __setup_rt_frame(sig, ka, info, set, regs); | |
1d13024e | 586 | |
3d0aedd9 HS |
587 | if (ret) { |
588 | force_sigsegv(sig, current); | |
589 | return -EFAULT; | |
590 | } | |
591 | ||
1d13024e HS |
592 | return ret; |
593 | } | |
594 | ||
7c1def16 | 595 | static int |
1da177e4 | 596 | handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, |
ac66f3fd | 597 | sigset_t *oldset, struct pt_regs *regs) |
1da177e4 | 598 | { |
7c1def16 RM |
599 | int ret; |
600 | ||
1da177e4 | 601 | /* Are we from a system call? */ |
bb57925f | 602 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 603 | /* If so, check system call restarting.. */ |
bb57925f | 604 | switch (syscall_get_error(current, regs)) { |
ac66f3fd HH |
605 | case -ERESTART_RESTARTBLOCK: |
606 | case -ERESTARTNOHAND: | |
607 | regs->ax = -EINTR; | |
608 | break; | |
609 | ||
610 | case -ERESTARTSYS: | |
611 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
65ea5b03 | 612 | regs->ax = -EINTR; |
1da177e4 | 613 | break; |
ac66f3fd HH |
614 | } |
615 | /* fallthrough */ | |
616 | case -ERESTARTNOINTR: | |
617 | regs->ax = regs->orig_ax; | |
618 | regs->ip -= 2; | |
619 | break; | |
1da177e4 LT |
620 | } |
621 | } | |
622 | ||
623 | /* | |
e1f28773 RM |
624 | * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF |
625 | * flag so that register information in the sigcontext is correct. | |
1da177e4 | 626 | */ |
65ea5b03 | 627 | if (unlikely(regs->flags & X86_EFLAGS_TF) && |
e1f28773 | 628 | likely(test_and_clear_thread_flag(TIF_FORCED_TF))) |
65ea5b03 | 629 | regs->flags &= ~X86_EFLAGS_TF; |
1da177e4 | 630 | |
1d13024e | 631 | ret = setup_rt_frame(sig, ka, info, oldset, regs); |
1da177e4 | 632 | |
7e907f48 IM |
633 | if (ret) |
634 | return ret; | |
7c1def16 | 635 | |
86d3237c HS |
636 | #ifdef CONFIG_X86_64 |
637 | /* | |
638 | * This has nothing to do with segment registers, | |
639 | * despite the name. This magic affects uaccess.h | |
640 | * macros' behavior. Reset it to the normal setting. | |
641 | */ | |
642 | set_fs(USER_DS); | |
643 | #endif | |
644 | ||
8b9c5ff3 RM |
645 | /* |
646 | * Clear the direction flag as per the ABI for function entry. | |
647 | */ | |
648 | regs->flags &= ~X86_EFLAGS_DF; | |
649 | ||
650 | /* | |
651 | * Clear TF when entering the signal handler, but | |
652 | * notify any tracer that was single-stepping it. | |
653 | * The tracer may want to single-step inside the | |
654 | * handler too. | |
655 | */ | |
656 | regs->flags &= ~X86_EFLAGS_TF; | |
8b9c5ff3 | 657 | |
7e907f48 IM |
658 | spin_lock_irq(¤t->sighand->siglock); |
659 | sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask); | |
660 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
661 | sigaddset(¤t->blocked, sig); | |
662 | recalc_sigpending(); | |
663 | spin_unlock_irq(¤t->sighand->siglock); | |
664 | ||
36a03308 RM |
665 | tracehook_signal_handler(sig, info, ka, regs, |
666 | test_thread_flag(TIF_SINGLESTEP)); | |
667 | ||
7e907f48 | 668 | return 0; |
1da177e4 LT |
669 | } |
670 | ||
57917752 | 671 | #ifdef CONFIG_X86_32 |
8fcd8e20 | 672 | #define NR_restart_syscall __NR_restart_syscall |
57917752 HS |
673 | #else /* !CONFIG_X86_32 */ |
674 | #define NR_restart_syscall \ | |
675 | test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall | |
676 | #endif /* CONFIG_X86_32 */ | |
677 | ||
1da177e4 LT |
678 | /* |
679 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
680 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
681 | * mistake. | |
682 | */ | |
75604d7f | 683 | static void do_signal(struct pt_regs *regs) |
1da177e4 | 684 | { |
ac66f3fd | 685 | struct k_sigaction ka; |
1da177e4 LT |
686 | siginfo_t info; |
687 | int signr; | |
283828f3 | 688 | sigset_t *oldset; |
1da177e4 LT |
689 | |
690 | /* | |
ac66f3fd HH |
691 | * We want the common case to go fast, which is why we may in certain |
692 | * cases get here from kernel mode. Just return without doing anything | |
693 | * if so. | |
694 | * X86_32: vm86 regs switched out by assembly code before reaching | |
695 | * here, so testing against kernel CS suffices. | |
1da177e4 | 696 | */ |
717b594a | 697 | if (!user_mode(regs)) |
283828f3 | 698 | return; |
1da177e4 | 699 | |
5a8da0ea | 700 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) |
283828f3 DH |
701 | oldset = ¤t->saved_sigmask; |
702 | else | |
1da177e4 LT |
703 | oldset = ¤t->blocked; |
704 | ||
705 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
706 | if (signr > 0) { | |
7e907f48 IM |
707 | /* |
708 | * Re-enable any watchpoints before delivering the | |
1da177e4 LT |
709 | * signal to user space. The processor register will |
710 | * have been cleared if the watchpoint triggered | |
711 | * inside the kernel. | |
712 | */ | |
ac66f3fd | 713 | if (current->thread.debugreg7) |
0f534093 | 714 | set_debugreg(current->thread.debugreg7, 7); |
1da177e4 | 715 | |
7e907f48 | 716 | /* Whee! Actually deliver the signal. */ |
283828f3 | 717 | if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { |
7e907f48 | 718 | /* |
5a8da0ea | 719 | * A signal was successfully delivered; the saved |
283828f3 DH |
720 | * sigmask will have been stored in the signal frame, |
721 | * and will be restored by sigreturn, so we can simply | |
5a8da0ea | 722 | * clear the TS_RESTORE_SIGMASK flag. |
7e907f48 | 723 | */ |
5a8da0ea | 724 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; |
283828f3 | 725 | } |
283828f3 | 726 | return; |
1da177e4 LT |
727 | } |
728 | ||
1da177e4 | 729 | /* Did we come from a system call? */ |
bb57925f | 730 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 731 | /* Restart the system call - no handlers present */ |
bb57925f | 732 | switch (syscall_get_error(current, regs)) { |
283828f3 DH |
733 | case -ERESTARTNOHAND: |
734 | case -ERESTARTSYS: | |
735 | case -ERESTARTNOINTR: | |
65ea5b03 PA |
736 | regs->ax = regs->orig_ax; |
737 | regs->ip -= 2; | |
283828f3 DH |
738 | break; |
739 | ||
740 | case -ERESTART_RESTARTBLOCK: | |
8fcd8e20 | 741 | regs->ax = NR_restart_syscall; |
65ea5b03 | 742 | regs->ip -= 2; |
283828f3 | 743 | break; |
1da177e4 LT |
744 | } |
745 | } | |
283828f3 | 746 | |
ac66f3fd HH |
747 | /* |
748 | * If there's no signal to deliver, we just put the saved sigmask | |
749 | * back. | |
750 | */ | |
5a8da0ea RM |
751 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) { |
752 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; | |
283828f3 DH |
753 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); |
754 | } | |
1da177e4 LT |
755 | } |
756 | ||
757 | /* | |
758 | * notification of userspace execution resumption | |
283828f3 | 759 | * - triggered by the TIF_WORK_MASK flags |
1da177e4 | 760 | */ |
7e907f48 IM |
761 | void |
762 | do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) | |
1da177e4 | 763 | { |
ee847c54 HS |
764 | #if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE) |
765 | /* notify userspace of pending MCEs */ | |
766 | if (thread_info_flags & _TIF_MCE_NOTIFY) | |
767 | mce_notify_user(); | |
768 | #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ | |
769 | ||
1da177e4 | 770 | /* deal with pending signal delivery */ |
5a8da0ea | 771 | if (thread_info_flags & _TIF_SIGPENDING) |
283828f3 | 772 | do_signal(regs); |
8f4d37ec | 773 | |
59e52130 RM |
774 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { |
775 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
776 | tracehook_notify_resume(regs); | |
777 | } | |
778 | ||
ee847c54 | 779 | #ifdef CONFIG_X86_32 |
1da177e4 | 780 | clear_thread_flag(TIF_IRET); |
ee847c54 | 781 | #endif /* CONFIG_X86_32 */ |
1da177e4 | 782 | } |
72fa50f4 HS |
783 | |
784 | void signal_fault(struct pt_regs *regs, void __user *frame, char *where) | |
785 | { | |
786 | struct task_struct *me = current; | |
787 | ||
788 | if (show_unhandled_signals && printk_ratelimit()) { | |
789 | printk(KERN_INFO | |
790 | "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx", | |
791 | me->comm, me->pid, where, frame, | |
792 | regs->ip, regs->sp, regs->orig_ax); | |
793 | print_vma_addr(" in ", regs->ip); | |
794 | printk(KERN_CONT "\n"); | |
795 | } | |
796 | ||
797 | force_sig(SIGSEGV, me); | |
798 | } |