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 | */ | |
7 | ||
5c9b3a0c HS |
8 | #include <linux/sched.h> |
9 | #include <linux/mm.h> | |
10 | #include <linux/smp.h> | |
1da177e4 LT |
11 | #include <linux/kernel.h> |
12 | #include <linux/signal.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/wait.h> | |
5c9b3a0c | 15 | #include <linux/ptrace.h> |
36a03308 | 16 | #include <linux/tracehook.h> |
5c9b3a0c HS |
17 | #include <linux/unistd.h> |
18 | #include <linux/stddef.h> | |
19 | #include <linux/personality.h> | |
20 | #include <linux/uaccess.h> | |
7e907f48 | 21 | |
1da177e4 LT |
22 | #include <asm/processor.h> |
23 | #include <asm/ucontext.h> | |
1da177e4 | 24 | #include <asm/i387.h> |
6c3652ef | 25 | #include <asm/vdso.h> |
5c9b3a0c HS |
26 | |
27 | #ifdef CONFIG_X86_64 | |
28 | #include <asm/proto.h> | |
29 | #include <asm/ia32_unistd.h> | |
30 | #include <asm/mce.h> | |
31 | #endif /* CONFIG_X86_64 */ | |
32 | ||
bb57925f | 33 | #include <asm/syscall.h> |
bbc1f698 | 34 | #include <asm/syscalls.h> |
7e907f48 | 35 | |
123a6347 | 36 | #include "sigframe.h" |
1da177e4 | 37 | |
1da177e4 LT |
38 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) |
39 | ||
1a176803 HH |
40 | #define __FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \ |
41 | X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \ | |
42 | X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \ | |
43 | X86_EFLAGS_CF) | |
44 | ||
45 | #ifdef CONFIG_X86_32 | |
46 | # define FIX_EFLAGS (__FIX_EFLAGS | X86_EFLAGS_RF) | |
47 | #else | |
48 | # define FIX_EFLAGS __FIX_EFLAGS | |
49 | #endif | |
50 | ||
4a612048 HS |
51 | static const struct { |
52 | u16 poplmovl; | |
53 | u32 val; | |
54 | u16 int80; | |
55 | } __attribute__((packed)) retcode = { | |
56 | 0xb858, /* popl %eax; movl $..., %eax */ | |
57 | __NR_sigreturn, | |
58 | 0x80cd, /* int $0x80 */ | |
59 | }; | |
60 | ||
61 | static const struct { | |
62 | u8 movl; | |
63 | u32 val; | |
64 | u16 int80; | |
65 | u8 pad; | |
66 | } __attribute__((packed)) rt_retcode = { | |
67 | 0xb8, /* movl $..., %eax */ | |
68 | __NR_rt_sigreturn, | |
69 | 0x80cd, /* int $0x80 */ | |
70 | 0 | |
71 | }; | |
72 | ||
1da177e4 LT |
73 | /* |
74 | * Atomically swap in the new signal mask, and wait for a signal. | |
75 | */ | |
76 | asmlinkage int | |
77 | sys_sigsuspend(int history0, int history1, old_sigset_t mask) | |
78 | { | |
1da177e4 LT |
79 | mask &= _BLOCKABLE; |
80 | spin_lock_irq(¤t->sighand->siglock); | |
283828f3 | 81 | current->saved_sigmask = current->blocked; |
1da177e4 LT |
82 | siginitset(¤t->blocked, mask); |
83 | recalc_sigpending(); | |
84 | spin_unlock_irq(¤t->sighand->siglock); | |
85 | ||
283828f3 DH |
86 | current->state = TASK_INTERRUPTIBLE; |
87 | schedule(); | |
5a8da0ea | 88 | set_restore_sigmask(); |
7e907f48 | 89 | |
283828f3 | 90 | return -ERESTARTNOHAND; |
1da177e4 LT |
91 | } |
92 | ||
7e907f48 | 93 | asmlinkage int |
1da177e4 LT |
94 | sys_sigaction(int sig, const struct old_sigaction __user *act, |
95 | struct old_sigaction __user *oact) | |
96 | { | |
97 | struct k_sigaction new_ka, old_ka; | |
98 | int ret; | |
99 | ||
100 | if (act) { | |
101 | old_sigset_t mask; | |
7e907f48 | 102 | |
1da177e4 LT |
103 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || |
104 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
105 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | |
106 | return -EFAULT; | |
7e907f48 | 107 | |
1da177e4 LT |
108 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); |
109 | __get_user(mask, &act->sa_mask); | |
110 | siginitset(&new_ka.sa.sa_mask, mask); | |
111 | } | |
112 | ||
113 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
114 | ||
115 | if (!ret && oact) { | |
116 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
117 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
118 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | |
119 | return -EFAULT; | |
7e907f48 | 120 | |
1da177e4 LT |
121 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); |
122 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
123 | } | |
124 | ||
125 | return ret; | |
126 | } | |
127 | ||
666ac7be | 128 | #ifdef CONFIG_X86_32 |
7e907f48 | 129 | asmlinkage int sys_sigaltstack(unsigned long bx) |
1da177e4 | 130 | { |
7e907f48 IM |
131 | /* |
132 | * This is needed to make gcc realize it doesn't own the | |
133 | * "struct pt_regs" | |
134 | */ | |
65ea5b03 PA |
135 | struct pt_regs *regs = (struct pt_regs *)&bx; |
136 | const stack_t __user *uss = (const stack_t __user *)bx; | |
137 | stack_t __user *uoss = (stack_t __user *)regs->cx; | |
1da177e4 | 138 | |
65ea5b03 | 139 | return do_sigaltstack(uss, uoss, regs->sp); |
1da177e4 | 140 | } |
666ac7be HS |
141 | #else /* !CONFIG_X86_32 */ |
142 | asmlinkage long | |
143 | sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, | |
144 | struct pt_regs *regs) | |
145 | { | |
146 | return do_sigaltstack(uss, uoss, regs->sp); | |
147 | } | |
148 | #endif /* CONFIG_X86_32 */ | |
1da177e4 | 149 | |
a2e8d3dc HS |
150 | #define COPY(x) { \ |
151 | err |= __get_user(regs->x, &sc->x); \ | |
152 | } | |
153 | ||
154 | #define COPY_SEG(seg) { \ | |
155 | unsigned short tmp; \ | |
156 | err |= __get_user(tmp, &sc->seg); \ | |
157 | regs->seg = tmp; \ | |
158 | } | |
159 | ||
3ddd972d | 160 | #define COPY_SEG_CPL3(seg) { \ |
a2e8d3dc HS |
161 | unsigned short tmp; \ |
162 | err |= __get_user(tmp, &sc->seg); \ | |
163 | regs->seg = tmp | 3; \ | |
164 | } | |
165 | ||
166 | #define GET_SEG(seg) { \ | |
167 | unsigned short tmp; \ | |
168 | err |= __get_user(tmp, &sc->seg); \ | |
169 | loadsegment(seg, tmp); \ | |
170 | } | |
1da177e4 LT |
171 | |
172 | /* | |
173 | * Do a signal return; undo the signal stack. | |
174 | */ | |
1da177e4 | 175 | static int |
866bc13f HH |
176 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, |
177 | unsigned long *pax) | |
1da177e4 | 178 | { |
69e13ad5 HS |
179 | void __user *buf; |
180 | unsigned int tmpflags; | |
1da177e4 LT |
181 | unsigned int err = 0; |
182 | ||
183 | /* Always make any pending restarted system calls return -EINTR */ | |
184 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
185 | ||
709110bd | 186 | #ifdef CONFIG_X86_32 |
464d1a78 JF |
187 | GET_SEG(gs); |
188 | COPY_SEG(fs); | |
1da177e4 LT |
189 | COPY_SEG(es); |
190 | COPY_SEG(ds); | |
709110bd HS |
191 | #endif /* CONFIG_X86_32 */ |
192 | ||
ac66f3fd HH |
193 | COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); |
194 | COPY(dx); COPY(cx); COPY(ip); | |
709110bd HS |
195 | |
196 | #ifdef CONFIG_X86_64 | |
197 | COPY(r8); | |
198 | COPY(r9); | |
199 | COPY(r10); | |
200 | COPY(r11); | |
201 | COPY(r12); | |
202 | COPY(r13); | |
203 | COPY(r14); | |
204 | COPY(r15); | |
205 | #endif /* CONFIG_X86_64 */ | |
206 | ||
207 | #ifdef CONFIG_X86_32 | |
3ddd972d HS |
208 | COPY_SEG_CPL3(cs); |
209 | COPY_SEG_CPL3(ss); | |
709110bd HS |
210 | #else /* !CONFIG_X86_32 */ |
211 | /* Kernel saves and restores only the CS segment register on signals, | |
212 | * which is the bare minimum needed to allow mixed 32/64-bit code. | |
213 | * App's signal handler can save/restore other segments if needed. */ | |
3ddd972d | 214 | COPY_SEG_CPL3(cs); |
709110bd | 215 | #endif /* CONFIG_X86_32 */ |
7e907f48 | 216 | |
69e13ad5 HS |
217 | err |= __get_user(tmpflags, &sc->flags); |
218 | regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
219 | regs->orig_ax = -1; /* disable syscall checks */ | |
7e907f48 | 220 | |
69e13ad5 HS |
221 | err |= __get_user(buf, &sc->fpstate); |
222 | err |= restore_i387_xstate(buf); | |
1da177e4 | 223 | |
866bc13f | 224 | err |= __get_user(*pax, &sc->ax); |
1da177e4 | 225 | return err; |
1da177e4 LT |
226 | } |
227 | ||
866bc13f | 228 | asmlinkage unsigned long sys_sigreturn(unsigned long __unused) |
1da177e4 | 229 | { |
7e907f48 IM |
230 | struct sigframe __user *frame; |
231 | struct pt_regs *regs; | |
866bc13f | 232 | unsigned long ax; |
7e907f48 IM |
233 | sigset_t set; |
234 | ||
235 | regs = (struct pt_regs *) &__unused; | |
236 | frame = (struct sigframe __user *)(regs->sp - 8); | |
1da177e4 LT |
237 | |
238 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
239 | goto badframe; | |
7e907f48 | 240 | if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1 |
1da177e4 LT |
241 | && __copy_from_user(&set.sig[1], &frame->extramask, |
242 | sizeof(frame->extramask)))) | |
243 | goto badframe; | |
244 | ||
245 | sigdelsetmask(&set, ~_BLOCKABLE); | |
246 | spin_lock_irq(¤t->sighand->siglock); | |
247 | current->blocked = set; | |
248 | recalc_sigpending(); | |
249 | spin_unlock_irq(¤t->sighand->siglock); | |
7e907f48 | 250 | |
65ea5b03 | 251 | if (restore_sigcontext(regs, &frame->sc, &ax)) |
1da177e4 | 252 | goto badframe; |
65ea5b03 | 253 | return ax; |
1da177e4 LT |
254 | |
255 | badframe: | |
03252919 | 256 | if (show_unhandled_signals && printk_ratelimit()) { |
1181f8b5 | 257 | printk("%s%s[%d] bad frame in sigreturn frame:" |
97b44ae6 | 258 | "%p ip:%lx sp:%lx oeax:%lx", |
19c5870c | 259 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
65ea5b03 PA |
260 | current->comm, task_pid_nr(current), frame, regs->ip, |
261 | regs->sp, regs->orig_ax); | |
03252919 | 262 | print_vma_addr(" in ", regs->ip); |
97b44ae6 | 263 | printk(KERN_CONT "\n"); |
03252919 | 264 | } |
abd4f750 | 265 | |
1da177e4 | 266 | force_sig(SIGSEGV, current); |
7e907f48 | 267 | |
1da177e4 | 268 | return 0; |
7e907f48 | 269 | } |
1da177e4 | 270 | |
e6babb6b | 271 | static long do_rt_sigreturn(struct pt_regs *regs) |
1da177e4 | 272 | { |
2d19c458 | 273 | struct rt_sigframe __user *frame; |
866bc13f | 274 | unsigned long ax; |
1da177e4 | 275 | sigset_t set; |
1da177e4 | 276 | |
2d19c458 | 277 | frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); |
1da177e4 LT |
278 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
279 | goto badframe; | |
280 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
281 | goto badframe; | |
282 | ||
283 | sigdelsetmask(&set, ~_BLOCKABLE); | |
284 | spin_lock_irq(¤t->sighand->siglock); | |
285 | current->blocked = set; | |
286 | recalc_sigpending(); | |
287 | spin_unlock_irq(¤t->sighand->siglock); | |
7e907f48 | 288 | |
65ea5b03 | 289 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) |
1da177e4 LT |
290 | goto badframe; |
291 | ||
65ea5b03 | 292 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT) |
1da177e4 LT |
293 | goto badframe; |
294 | ||
65ea5b03 | 295 | return ax; |
1da177e4 LT |
296 | |
297 | badframe: | |
e6babb6b | 298 | signal_fault(regs, frame, "rt_sigreturn"); |
1da177e4 | 299 | return 0; |
7e907f48 | 300 | } |
1da177e4 | 301 | |
e6babb6b HS |
302 | asmlinkage int sys_rt_sigreturn(unsigned long __unused) |
303 | { | |
304 | struct pt_regs *regs = (struct pt_regs *)&__unused; | |
305 | ||
306 | return do_rt_sigreturn(regs); | |
307 | } | |
308 | ||
1da177e4 LT |
309 | /* |
310 | * Set up a signal frame. | |
311 | */ | |
1da177e4 | 312 | static int |
ab513701 | 313 | setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, |
1da177e4 LT |
314 | struct pt_regs *regs, unsigned long mask) |
315 | { | |
15002fa9 | 316 | int err = 0; |
1da177e4 | 317 | |
15002fa9 HS |
318 | #ifdef CONFIG_X86_32 |
319 | { | |
320 | unsigned int tmp; | |
1da177e4 | 321 | |
15002fa9 HS |
322 | savesegment(gs, tmp); |
323 | err |= __put_user(tmp, (unsigned int __user *)&sc->gs); | |
324 | } | |
325 | err |= __put_user(regs->fs, (unsigned int __user *)&sc->fs); | |
65ea5b03 PA |
326 | err |= __put_user(regs->es, (unsigned int __user *)&sc->es); |
327 | err |= __put_user(regs->ds, (unsigned int __user *)&sc->ds); | |
15002fa9 HS |
328 | #endif /* CONFIG_X86_32 */ |
329 | ||
742fa54a PA |
330 | err |= __put_user(regs->di, &sc->di); |
331 | err |= __put_user(regs->si, &sc->si); | |
332 | err |= __put_user(regs->bp, &sc->bp); | |
333 | err |= __put_user(regs->sp, &sc->sp); | |
334 | err |= __put_user(regs->bx, &sc->bx); | |
335 | err |= __put_user(regs->dx, &sc->dx); | |
336 | err |= __put_user(regs->cx, &sc->cx); | |
337 | err |= __put_user(regs->ax, &sc->ax); | |
15002fa9 HS |
338 | #ifdef CONFIG_X86_64 |
339 | err |= __put_user(regs->r8, &sc->r8); | |
340 | err |= __put_user(regs->r9, &sc->r9); | |
341 | err |= __put_user(regs->r10, &sc->r10); | |
342 | err |= __put_user(regs->r11, &sc->r11); | |
343 | err |= __put_user(regs->r12, &sc->r12); | |
344 | err |= __put_user(regs->r13, &sc->r13); | |
345 | err |= __put_user(regs->r14, &sc->r14); | |
346 | err |= __put_user(regs->r15, &sc->r15); | |
347 | #endif /* CONFIG_X86_64 */ | |
348 | ||
1da177e4 LT |
349 | err |= __put_user(current->thread.trap_no, &sc->trapno); |
350 | err |= __put_user(current->thread.error_code, &sc->err); | |
742fa54a | 351 | err |= __put_user(regs->ip, &sc->ip); |
15002fa9 | 352 | #ifdef CONFIG_X86_32 |
65ea5b03 | 353 | err |= __put_user(regs->cs, (unsigned int __user *)&sc->cs); |
742fa54a PA |
354 | err |= __put_user(regs->flags, &sc->flags); |
355 | err |= __put_user(regs->sp, &sc->sp_at_signal); | |
65ea5b03 | 356 | err |= __put_user(regs->ss, (unsigned int __user *)&sc->ss); |
15002fa9 HS |
357 | #else /* !CONFIG_X86_32 */ |
358 | err |= __put_user(regs->flags, &sc->flags); | |
359 | err |= __put_user(regs->cs, &sc->cs); | |
360 | err |= __put_user(0, &sc->gs); | |
361 | err |= __put_user(0, &sc->fs); | |
362 | #endif /* CONFIG_X86_32 */ | |
1da177e4 | 363 | |
4b33669e | 364 | err |= __put_user(fpstate, &sc->fpstate); |
1da177e4 LT |
365 | |
366 | /* non-iBCS2 extensions.. */ | |
367 | err |= __put_user(mask, &sc->oldmask); | |
368 | err |= __put_user(current->thread.cr2, &sc->cr2); | |
369 | ||
370 | return err; | |
371 | } | |
372 | ||
373 | /* | |
374 | * Determine which stack to use.. | |
375 | */ | |
376 | static inline void __user * | |
3c1c7f10 | 377 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, |
ab513701 | 378 | void **fpstate) |
1da177e4 | 379 | { |
65ea5b03 | 380 | unsigned long sp; |
1da177e4 LT |
381 | |
382 | /* Default to using normal stack */ | |
65ea5b03 | 383 | sp = regs->sp; |
1da177e4 | 384 | |
83bd0102 RM |
385 | /* |
386 | * If we are on the alternate signal stack and would overflow it, don't. | |
387 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
388 | */ | |
65ea5b03 | 389 | if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size))) |
83bd0102 RM |
390 | return (void __user *) -1L; |
391 | ||
1da177e4 LT |
392 | /* This is the X/Open sanctioned signal stack switching. */ |
393 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
65ea5b03 PA |
394 | if (sas_ss_flags(sp) == 0) |
395 | sp = current->sas_ss_sp + current->sas_ss_size; | |
7e907f48 IM |
396 | } else { |
397 | /* This is the legacy signal stack switching. */ | |
398 | if ((regs->ss & 0xffff) != __USER_DS && | |
399 | !(ka->sa.sa_flags & SA_RESTORER) && | |
400 | ka->sa.sa_restorer) | |
401 | sp = (unsigned long) ka->sa.sa_restorer; | |
1da177e4 LT |
402 | } |
403 | ||
3c1c7f10 SS |
404 | if (used_math()) { |
405 | sp = sp - sig_xstate_size; | |
406 | *fpstate = (struct _fpstate *) sp; | |
4b33669e HS |
407 | if (save_i387_xstate(*fpstate) < 0) |
408 | return (void __user *)-1L; | |
3c1c7f10 SS |
409 | } |
410 | ||
65ea5b03 | 411 | sp -= frame_size; |
7e907f48 IM |
412 | /* |
413 | * Align the stack pointer according to the i386 ABI, | |
414 | * i.e. so that on function entry ((sp + 4) & 15) == 0. | |
415 | */ | |
65ea5b03 | 416 | sp = ((sp + 4) & -16ul) - 4; |
7e907f48 | 417 | |
65ea5b03 | 418 | return (void __user *) sp; |
1da177e4 LT |
419 | } |
420 | ||
7e907f48 | 421 | static int |
1d13024e HS |
422 | __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, |
423 | struct pt_regs *regs) | |
1da177e4 | 424 | { |
1da177e4 | 425 | struct sigframe __user *frame; |
7e907f48 | 426 | void __user *restorer; |
1da177e4 | 427 | int err = 0; |
ab513701 | 428 | void __user *fpstate = NULL; |
1da177e4 | 429 | |
3c1c7f10 | 430 | frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
431 | |
432 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 433 | return -EFAULT; |
1da177e4 | 434 | |
2ba48e16 | 435 | if (__put_user(sig, &frame->sig)) |
3d0aedd9 | 436 | return -EFAULT; |
1da177e4 | 437 | |
2ba48e16 | 438 | if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0])) |
3d0aedd9 | 439 | return -EFAULT; |
1da177e4 LT |
440 | |
441 | if (_NSIG_WORDS > 1) { | |
2ba48e16 HS |
442 | if (__copy_to_user(&frame->extramask, &set->sig[1], |
443 | sizeof(frame->extramask))) | |
3d0aedd9 | 444 | return -EFAULT; |
1da177e4 LT |
445 | } |
446 | ||
1a3e4ca4 | 447 | if (current->mm->context.vdso) |
6c3652ef | 448 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn); |
9fbbd4dd | 449 | else |
ade1af77 | 450 | restorer = &frame->retcode; |
1da177e4 LT |
451 | if (ka->sa.sa_flags & SA_RESTORER) |
452 | restorer = ka->sa.sa_restorer; | |
453 | ||
454 | /* Set up to return from userspace. */ | |
455 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 456 | |
1da177e4 | 457 | /* |
7e907f48 | 458 | * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 |
1da177e4 LT |
459 | * |
460 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
461 | * reasons and because gdb uses it as a signature to notice | |
462 | * signal handler stack frames. | |
463 | */ | |
4a612048 | 464 | err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode); |
1da177e4 LT |
465 | |
466 | if (err) | |
3d0aedd9 | 467 | return -EFAULT; |
1da177e4 LT |
468 | |
469 | /* Set up registers for signal handler */ | |
7e907f48 IM |
470 | regs->sp = (unsigned long)frame; |
471 | regs->ip = (unsigned long)ka->sa.sa_handler; | |
472 | regs->ax = (unsigned long)sig; | |
92bc2056 HH |
473 | regs->dx = 0; |
474 | regs->cx = 0; | |
1da177e4 | 475 | |
65ea5b03 PA |
476 | regs->ds = __USER_DS; |
477 | regs->es = __USER_DS; | |
478 | regs->ss = __USER_DS; | |
479 | regs->cs = __USER_CS; | |
1da177e4 | 480 | |
283828f3 | 481 | return 0; |
1da177e4 LT |
482 | } |
483 | ||
1d13024e HS |
484 | static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
485 | sigset_t *set, struct pt_regs *regs) | |
1da177e4 | 486 | { |
1da177e4 | 487 | struct rt_sigframe __user *frame; |
7e907f48 | 488 | void __user *restorer; |
1da177e4 | 489 | int err = 0; |
ab513701 | 490 | void __user *fpstate = NULL; |
1da177e4 | 491 | |
3c1c7f10 | 492 | frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
493 | |
494 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 495 | return -EFAULT; |
1da177e4 | 496 | |
13ad7725 | 497 | err |= __put_user(sig, &frame->sig); |
1da177e4 LT |
498 | err |= __put_user(&frame->info, &frame->pinfo); |
499 | err |= __put_user(&frame->uc, &frame->puc); | |
500 | err |= copy_siginfo_to_user(&frame->info, info); | |
501 | if (err) | |
3d0aedd9 | 502 | return -EFAULT; |
1da177e4 LT |
503 | |
504 | /* Create the ucontext. */ | |
c37b5efe SS |
505 | if (cpu_has_xsave) |
506 | err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags); | |
507 | else | |
508 | err |= __put_user(0, &frame->uc.uc_flags); | |
1da177e4 LT |
509 | err |= __put_user(0, &frame->uc.uc_link); |
510 | err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
65ea5b03 | 511 | err |= __put_user(sas_ss_flags(regs->sp), |
1da177e4 LT |
512 | &frame->uc.uc_stack.ss_flags); |
513 | err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
3c1c7f10 | 514 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
7e907f48 | 515 | regs, set->sig[0]); |
1da177e4 LT |
516 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); |
517 | if (err) | |
3d0aedd9 | 518 | return -EFAULT; |
1da177e4 LT |
519 | |
520 | /* Set up to return from userspace. */ | |
6c3652ef | 521 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn); |
1da177e4 LT |
522 | if (ka->sa.sa_flags & SA_RESTORER) |
523 | restorer = ka->sa.sa_restorer; | |
524 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 525 | |
1da177e4 | 526 | /* |
7e907f48 | 527 | * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 |
1da177e4 LT |
528 | * |
529 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
530 | * reasons and because gdb uses it as a signature to notice | |
531 | * signal handler stack frames. | |
532 | */ | |
4a612048 | 533 | err |= __put_user(*((u64 *)&rt_retcode), (u64 *)frame->retcode); |
1da177e4 LT |
534 | |
535 | if (err) | |
3d0aedd9 | 536 | return -EFAULT; |
1da177e4 LT |
537 | |
538 | /* Set up registers for signal handler */ | |
7e907f48 IM |
539 | regs->sp = (unsigned long)frame; |
540 | regs->ip = (unsigned long)ka->sa.sa_handler; | |
13ad7725 | 541 | regs->ax = (unsigned long)sig; |
7e907f48 IM |
542 | regs->dx = (unsigned long)&frame->info; |
543 | regs->cx = (unsigned long)&frame->uc; | |
1da177e4 | 544 | |
65ea5b03 PA |
545 | regs->ds = __USER_DS; |
546 | regs->es = __USER_DS; | |
547 | regs->ss = __USER_DS; | |
548 | regs->cs = __USER_CS; | |
1da177e4 | 549 | |
283828f3 | 550 | return 0; |
1da177e4 LT |
551 | } |
552 | ||
553 | /* | |
7e907f48 IM |
554 | * OK, we're invoking a handler: |
555 | */ | |
8d8c13bd HS |
556 | static int signr_convert(int sig) |
557 | { | |
96bf84b7 | 558 | #ifdef CONFIG_X86_32 |
8d8c13bd HS |
559 | struct thread_info *info = current_thread_info(); |
560 | ||
561 | if (info->exec_domain && info->exec_domain->signal_invmap && sig < 32) | |
562 | return info->exec_domain->signal_invmap[sig]; | |
96bf84b7 | 563 | #endif /* CONFIG_X86_32 */ |
8d8c13bd HS |
564 | return sig; |
565 | } | |
566 | ||
cabf5035 HS |
567 | #ifdef CONFIG_X86_32 |
568 | ||
455edbc4 | 569 | #define is_ia32 1 |
4694d239 HS |
570 | #define ia32_setup_frame __setup_frame |
571 | #define ia32_setup_rt_frame __setup_rt_frame | |
455edbc4 | 572 | |
cabf5035 HS |
573 | #else /* !CONFIG_X86_32 */ |
574 | ||
575 | #ifdef CONFIG_IA32_EMULATION | |
576 | #define is_ia32 test_thread_flag(TIF_IA32) | |
577 | #else /* !CONFIG_IA32_EMULATION */ | |
578 | #define is_ia32 0 | |
579 | #endif /* CONFIG_IA32_EMULATION */ | |
580 | ||
581 | #endif /* CONFIG_X86_32 */ | |
582 | ||
1d13024e HS |
583 | static int |
584 | setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
585 | sigset_t *set, struct pt_regs *regs) | |
586 | { | |
8d8c13bd | 587 | int usig = signr_convert(sig); |
1d13024e HS |
588 | int ret; |
589 | ||
590 | /* Set up the stack frame */ | |
455edbc4 HS |
591 | if (is_ia32) { |
592 | if (ka->sa.sa_flags & SA_SIGINFO) | |
4694d239 | 593 | ret = ia32_setup_rt_frame(usig, ka, info, set, regs); |
455edbc4 | 594 | else |
4694d239 | 595 | ret = ia32_setup_frame(usig, ka, set, regs); |
455edbc4 HS |
596 | } else |
597 | ret = __setup_rt_frame(sig, ka, info, set, regs); | |
1d13024e | 598 | |
3d0aedd9 HS |
599 | if (ret) { |
600 | force_sigsegv(sig, current); | |
601 | return -EFAULT; | |
602 | } | |
603 | ||
1d13024e HS |
604 | return ret; |
605 | } | |
606 | ||
7c1def16 | 607 | static int |
1da177e4 | 608 | handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, |
ac66f3fd | 609 | sigset_t *oldset, struct pt_regs *regs) |
1da177e4 | 610 | { |
7c1def16 RM |
611 | int ret; |
612 | ||
1da177e4 | 613 | /* Are we from a system call? */ |
bb57925f | 614 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 615 | /* If so, check system call restarting.. */ |
bb57925f | 616 | switch (syscall_get_error(current, regs)) { |
ac66f3fd HH |
617 | case -ERESTART_RESTARTBLOCK: |
618 | case -ERESTARTNOHAND: | |
619 | regs->ax = -EINTR; | |
620 | break; | |
621 | ||
622 | case -ERESTARTSYS: | |
623 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
65ea5b03 | 624 | regs->ax = -EINTR; |
1da177e4 | 625 | break; |
ac66f3fd HH |
626 | } |
627 | /* fallthrough */ | |
628 | case -ERESTARTNOINTR: | |
629 | regs->ax = regs->orig_ax; | |
630 | regs->ip -= 2; | |
631 | break; | |
1da177e4 LT |
632 | } |
633 | } | |
634 | ||
635 | /* | |
e1f28773 RM |
636 | * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF |
637 | * flag so that register information in the sigcontext is correct. | |
1da177e4 | 638 | */ |
65ea5b03 | 639 | if (unlikely(regs->flags & X86_EFLAGS_TF) && |
e1f28773 | 640 | likely(test_and_clear_thread_flag(TIF_FORCED_TF))) |
65ea5b03 | 641 | regs->flags &= ~X86_EFLAGS_TF; |
1da177e4 | 642 | |
1d13024e | 643 | ret = setup_rt_frame(sig, ka, info, oldset, regs); |
1da177e4 | 644 | |
7e907f48 IM |
645 | if (ret) |
646 | return ret; | |
7c1def16 | 647 | |
86d3237c HS |
648 | #ifdef CONFIG_X86_64 |
649 | /* | |
650 | * This has nothing to do with segment registers, | |
651 | * despite the name. This magic affects uaccess.h | |
652 | * macros' behavior. Reset it to the normal setting. | |
653 | */ | |
654 | set_fs(USER_DS); | |
655 | #endif | |
656 | ||
8b9c5ff3 RM |
657 | /* |
658 | * Clear the direction flag as per the ABI for function entry. | |
659 | */ | |
660 | regs->flags &= ~X86_EFLAGS_DF; | |
661 | ||
662 | /* | |
663 | * Clear TF when entering the signal handler, but | |
664 | * notify any tracer that was single-stepping it. | |
665 | * The tracer may want to single-step inside the | |
666 | * handler too. | |
667 | */ | |
668 | regs->flags &= ~X86_EFLAGS_TF; | |
8b9c5ff3 | 669 | |
7e907f48 IM |
670 | spin_lock_irq(¤t->sighand->siglock); |
671 | sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask); | |
672 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
673 | sigaddset(¤t->blocked, sig); | |
674 | recalc_sigpending(); | |
675 | spin_unlock_irq(¤t->sighand->siglock); | |
676 | ||
36a03308 RM |
677 | tracehook_signal_handler(sig, info, ka, regs, |
678 | test_thread_flag(TIF_SINGLESTEP)); | |
679 | ||
7e907f48 | 680 | return 0; |
1da177e4 LT |
681 | } |
682 | ||
57917752 | 683 | #ifdef CONFIG_X86_32 |
8fcd8e20 | 684 | #define NR_restart_syscall __NR_restart_syscall |
57917752 HS |
685 | #else /* !CONFIG_X86_32 */ |
686 | #define NR_restart_syscall \ | |
687 | test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall | |
688 | #endif /* CONFIG_X86_32 */ | |
689 | ||
1da177e4 LT |
690 | /* |
691 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
692 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
693 | * mistake. | |
694 | */ | |
75604d7f | 695 | static void do_signal(struct pt_regs *regs) |
1da177e4 | 696 | { |
ac66f3fd | 697 | struct k_sigaction ka; |
1da177e4 LT |
698 | siginfo_t info; |
699 | int signr; | |
283828f3 | 700 | sigset_t *oldset; |
1da177e4 LT |
701 | |
702 | /* | |
ac66f3fd HH |
703 | * We want the common case to go fast, which is why we may in certain |
704 | * cases get here from kernel mode. Just return without doing anything | |
705 | * if so. | |
706 | * X86_32: vm86 regs switched out by assembly code before reaching | |
707 | * here, so testing against kernel CS suffices. | |
1da177e4 | 708 | */ |
717b594a | 709 | if (!user_mode(regs)) |
283828f3 | 710 | return; |
1da177e4 | 711 | |
5a8da0ea | 712 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) |
283828f3 DH |
713 | oldset = ¤t->saved_sigmask; |
714 | else | |
1da177e4 LT |
715 | oldset = ¤t->blocked; |
716 | ||
717 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
718 | if (signr > 0) { | |
7e907f48 IM |
719 | /* |
720 | * Re-enable any watchpoints before delivering the | |
1da177e4 LT |
721 | * signal to user space. The processor register will |
722 | * have been cleared if the watchpoint triggered | |
723 | * inside the kernel. | |
724 | */ | |
ac66f3fd | 725 | if (current->thread.debugreg7) |
0f534093 | 726 | set_debugreg(current->thread.debugreg7, 7); |
1da177e4 | 727 | |
7e907f48 | 728 | /* Whee! Actually deliver the signal. */ |
283828f3 | 729 | if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { |
7e907f48 | 730 | /* |
5a8da0ea | 731 | * A signal was successfully delivered; the saved |
283828f3 DH |
732 | * sigmask will have been stored in the signal frame, |
733 | * and will be restored by sigreturn, so we can simply | |
5a8da0ea | 734 | * clear the TS_RESTORE_SIGMASK flag. |
7e907f48 | 735 | */ |
5a8da0ea | 736 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; |
283828f3 | 737 | } |
283828f3 | 738 | return; |
1da177e4 LT |
739 | } |
740 | ||
1da177e4 | 741 | /* Did we come from a system call? */ |
bb57925f | 742 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 743 | /* Restart the system call - no handlers present */ |
bb57925f | 744 | switch (syscall_get_error(current, regs)) { |
283828f3 DH |
745 | case -ERESTARTNOHAND: |
746 | case -ERESTARTSYS: | |
747 | case -ERESTARTNOINTR: | |
65ea5b03 PA |
748 | regs->ax = regs->orig_ax; |
749 | regs->ip -= 2; | |
283828f3 DH |
750 | break; |
751 | ||
752 | case -ERESTART_RESTARTBLOCK: | |
8fcd8e20 | 753 | regs->ax = NR_restart_syscall; |
65ea5b03 | 754 | regs->ip -= 2; |
283828f3 | 755 | break; |
1da177e4 LT |
756 | } |
757 | } | |
283828f3 | 758 | |
ac66f3fd HH |
759 | /* |
760 | * If there's no signal to deliver, we just put the saved sigmask | |
761 | * back. | |
762 | */ | |
5a8da0ea RM |
763 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) { |
764 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; | |
283828f3 DH |
765 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); |
766 | } | |
1da177e4 LT |
767 | } |
768 | ||
769 | /* | |
770 | * notification of userspace execution resumption | |
283828f3 | 771 | * - triggered by the TIF_WORK_MASK flags |
1da177e4 | 772 | */ |
7e907f48 IM |
773 | void |
774 | do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) | |
1da177e4 | 775 | { |
ee847c54 HS |
776 | #if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE) |
777 | /* notify userspace of pending MCEs */ | |
778 | if (thread_info_flags & _TIF_MCE_NOTIFY) | |
779 | mce_notify_user(); | |
780 | #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ | |
781 | ||
1da177e4 | 782 | /* deal with pending signal delivery */ |
5a8da0ea | 783 | if (thread_info_flags & _TIF_SIGPENDING) |
283828f3 | 784 | do_signal(regs); |
8f4d37ec | 785 | |
59e52130 RM |
786 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { |
787 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
788 | tracehook_notify_resume(regs); | |
789 | } | |
790 | ||
ee847c54 | 791 | #ifdef CONFIG_X86_32 |
1da177e4 | 792 | clear_thread_flag(TIF_IRET); |
ee847c54 | 793 | #endif /* CONFIG_X86_32 */ |
1da177e4 | 794 | } |
72fa50f4 HS |
795 | |
796 | void signal_fault(struct pt_regs *regs, void __user *frame, char *where) | |
797 | { | |
798 | struct task_struct *me = current; | |
799 | ||
800 | if (show_unhandled_signals && printk_ratelimit()) { | |
801 | printk(KERN_INFO | |
802 | "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx", | |
803 | me->comm, me->pid, where, frame, | |
804 | regs->ip, regs->sp, regs->orig_ax); | |
805 | print_vma_addr(" in ", regs->ip); | |
806 | printk(KERN_CONT "\n"); | |
807 | } | |
808 | ||
809 | force_sig(SIGSEGV, me); | |
810 | } |