Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 | 2 | * Copyright (C) 1991, 1992 Linus Torvalds |
e5fa2d06 | 3 | * Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs |
1da177e4 LT |
4 | * |
5 | * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson | |
6 | * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes | |
e5fa2d06 | 7 | * 2000-2002 x86-64 support by Andi Kleen |
1da177e4 LT |
8 | */ |
9 | ||
5c9b3a0c HS |
10 | #include <linux/sched.h> |
11 | #include <linux/mm.h> | |
12 | #include <linux/smp.h> | |
1da177e4 LT |
13 | #include <linux/kernel.h> |
14 | #include <linux/signal.h> | |
15 | #include <linux/errno.h> | |
16 | #include <linux/wait.h> | |
5c9b3a0c | 17 | #include <linux/ptrace.h> |
36a03308 | 18 | #include <linux/tracehook.h> |
5c9b3a0c HS |
19 | #include <linux/unistd.h> |
20 | #include <linux/stddef.h> | |
21 | #include <linux/personality.h> | |
22 | #include <linux/uaccess.h> | |
7e907f48 | 23 | |
1da177e4 LT |
24 | #include <asm/processor.h> |
25 | #include <asm/ucontext.h> | |
1da177e4 | 26 | #include <asm/i387.h> |
6c3652ef | 27 | #include <asm/vdso.h> |
5c9b3a0c HS |
28 | |
29 | #ifdef CONFIG_X86_64 | |
30 | #include <asm/proto.h> | |
31 | #include <asm/ia32_unistd.h> | |
32 | #include <asm/mce.h> | |
33 | #endif /* CONFIG_X86_64 */ | |
34 | ||
bb57925f | 35 | #include <asm/syscall.h> |
bbc1f698 | 36 | #include <asm/syscalls.h> |
7e907f48 | 37 | |
41af86fa | 38 | #include <asm/sigframe.h> |
1da177e4 | 39 | |
1da177e4 LT |
40 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) |
41 | ||
1a176803 HH |
42 | #define __FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \ |
43 | X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \ | |
44 | X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \ | |
45 | X86_EFLAGS_CF) | |
46 | ||
47 | #ifdef CONFIG_X86_32 | |
48 | # define FIX_EFLAGS (__FIX_EFLAGS | X86_EFLAGS_RF) | |
49 | #else | |
50 | # define FIX_EFLAGS __FIX_EFLAGS | |
51 | #endif | |
52 | ||
d9a89a26 TH |
53 | #define COPY(x) do { \ |
54 | get_user_ex(regs->x, &sc->x); \ | |
55 | } while (0) | |
2601657d | 56 | |
d9a89a26 TH |
57 | #define GET_SEG(seg) ({ \ |
58 | unsigned short tmp; \ | |
59 | get_user_ex(tmp, &sc->seg); \ | |
60 | tmp; \ | |
61 | }) | |
2601657d | 62 | |
d9a89a26 TH |
63 | #define COPY_SEG(seg) do { \ |
64 | regs->seg = GET_SEG(seg); \ | |
65 | } while (0) | |
2601657d | 66 | |
d9a89a26 TH |
67 | #define COPY_SEG_CPL3(seg) do { \ |
68 | regs->seg = GET_SEG(seg) | 3; \ | |
69 | } while (0) | |
2601657d HS |
70 | |
71 | static int | |
72 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, | |
73 | unsigned long *pax) | |
74 | { | |
75 | void __user *buf; | |
76 | unsigned int tmpflags; | |
77 | unsigned int err = 0; | |
78 | ||
79 | /* Always make any pending restarted system calls return -EINTR */ | |
80 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
81 | ||
98e3d45e HS |
82 | get_user_try { |
83 | ||
2601657d | 84 | #ifdef CONFIG_X86_32 |
d9a89a26 | 85 | set_user_gs(regs, GET_SEG(gs)); |
98e3d45e HS |
86 | COPY_SEG(fs); |
87 | COPY_SEG(es); | |
88 | COPY_SEG(ds); | |
2601657d HS |
89 | #endif /* CONFIG_X86_32 */ |
90 | ||
98e3d45e HS |
91 | COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); |
92 | COPY(dx); COPY(cx); COPY(ip); | |
2601657d HS |
93 | |
94 | #ifdef CONFIG_X86_64 | |
98e3d45e HS |
95 | COPY(r8); |
96 | COPY(r9); | |
97 | COPY(r10); | |
98 | COPY(r11); | |
99 | COPY(r12); | |
100 | COPY(r13); | |
101 | COPY(r14); | |
102 | COPY(r15); | |
2601657d HS |
103 | #endif /* CONFIG_X86_64 */ |
104 | ||
105 | #ifdef CONFIG_X86_32 | |
98e3d45e HS |
106 | COPY_SEG_CPL3(cs); |
107 | COPY_SEG_CPL3(ss); | |
2601657d | 108 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
109 | /* Kernel saves and restores only the CS segment register on signals, |
110 | * which is the bare minimum needed to allow mixed 32/64-bit code. | |
111 | * App's signal handler can save/restore other segments if needed. */ | |
112 | COPY_SEG_CPL3(cs); | |
2601657d HS |
113 | #endif /* CONFIG_X86_32 */ |
114 | ||
98e3d45e HS |
115 | get_user_ex(tmpflags, &sc->flags); |
116 | regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
117 | regs->orig_ax = -1; /* disable syscall checks */ | |
118 | ||
119 | get_user_ex(buf, &sc->fpstate); | |
120 | err |= restore_i387_xstate(buf); | |
2601657d | 121 | |
98e3d45e HS |
122 | get_user_ex(*pax, &sc->ax); |
123 | } get_user_catch(err); | |
2601657d | 124 | |
2601657d HS |
125 | return err; |
126 | } | |
127 | ||
128 | static int | |
129 | setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, | |
130 | struct pt_regs *regs, unsigned long mask) | |
131 | { | |
132 | int err = 0; | |
133 | ||
98e3d45e | 134 | put_user_try { |
2601657d | 135 | |
98e3d45e | 136 | #ifdef CONFIG_X86_32 |
d9a89a26 | 137 | put_user_ex(get_user_gs(regs), (unsigned int __user *)&sc->gs); |
98e3d45e HS |
138 | put_user_ex(regs->fs, (unsigned int __user *)&sc->fs); |
139 | put_user_ex(regs->es, (unsigned int __user *)&sc->es); | |
140 | put_user_ex(regs->ds, (unsigned int __user *)&sc->ds); | |
2601657d HS |
141 | #endif /* CONFIG_X86_32 */ |
142 | ||
98e3d45e HS |
143 | put_user_ex(regs->di, &sc->di); |
144 | put_user_ex(regs->si, &sc->si); | |
145 | put_user_ex(regs->bp, &sc->bp); | |
146 | put_user_ex(regs->sp, &sc->sp); | |
147 | put_user_ex(regs->bx, &sc->bx); | |
148 | put_user_ex(regs->dx, &sc->dx); | |
149 | put_user_ex(regs->cx, &sc->cx); | |
150 | put_user_ex(regs->ax, &sc->ax); | |
2601657d | 151 | #ifdef CONFIG_X86_64 |
98e3d45e HS |
152 | put_user_ex(regs->r8, &sc->r8); |
153 | put_user_ex(regs->r9, &sc->r9); | |
154 | put_user_ex(regs->r10, &sc->r10); | |
155 | put_user_ex(regs->r11, &sc->r11); | |
156 | put_user_ex(regs->r12, &sc->r12); | |
157 | put_user_ex(regs->r13, &sc->r13); | |
158 | put_user_ex(regs->r14, &sc->r14); | |
159 | put_user_ex(regs->r15, &sc->r15); | |
2601657d HS |
160 | #endif /* CONFIG_X86_64 */ |
161 | ||
98e3d45e HS |
162 | put_user_ex(current->thread.trap_no, &sc->trapno); |
163 | put_user_ex(current->thread.error_code, &sc->err); | |
164 | put_user_ex(regs->ip, &sc->ip); | |
2601657d | 165 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
166 | put_user_ex(regs->cs, (unsigned int __user *)&sc->cs); |
167 | put_user_ex(regs->flags, &sc->flags); | |
168 | put_user_ex(regs->sp, &sc->sp_at_signal); | |
169 | put_user_ex(regs->ss, (unsigned int __user *)&sc->ss); | |
2601657d | 170 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
171 | put_user_ex(regs->flags, &sc->flags); |
172 | put_user_ex(regs->cs, &sc->cs); | |
173 | put_user_ex(0, &sc->gs); | |
174 | put_user_ex(0, &sc->fs); | |
2601657d HS |
175 | #endif /* CONFIG_X86_32 */ |
176 | ||
98e3d45e | 177 | put_user_ex(fpstate, &sc->fpstate); |
2601657d | 178 | |
98e3d45e HS |
179 | /* non-iBCS2 extensions.. */ |
180 | put_user_ex(mask, &sc->oldmask); | |
181 | put_user_ex(current->thread.cr2, &sc->cr2); | |
182 | } put_user_catch(err); | |
2601657d HS |
183 | |
184 | return err; | |
185 | } | |
186 | ||
1da177e4 | 187 | /* |
bfeb91a9 | 188 | * Set up a signal frame. |
1da177e4 | 189 | */ |
2456d738 | 190 | #ifdef CONFIG_X86_32 |
bfeb91a9 HS |
191 | static const struct { |
192 | u16 poplmovl; | |
193 | u32 val; | |
194 | u16 int80; | |
195 | } __attribute__((packed)) retcode = { | |
196 | 0xb858, /* popl %eax; movl $..., %eax */ | |
197 | __NR_sigreturn, | |
198 | 0x80cd, /* int $0x80 */ | |
199 | }; | |
e6babb6b | 200 | |
bfeb91a9 HS |
201 | static const struct { |
202 | u8 movl; | |
203 | u32 val; | |
204 | u16 int80; | |
205 | u8 pad; | |
206 | } __attribute__((packed)) rt_retcode = { | |
207 | 0xb8, /* movl $..., %eax */ | |
208 | __NR_rt_sigreturn, | |
209 | 0x80cd, /* int $0x80 */ | |
210 | 0 | |
211 | }; | |
1da177e4 LT |
212 | |
213 | /* | |
214 | * Determine which stack to use.. | |
215 | */ | |
216 | static inline void __user * | |
3c1c7f10 | 217 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, |
ab513701 | 218 | void **fpstate) |
1da177e4 | 219 | { |
65ea5b03 | 220 | unsigned long sp; |
1da177e4 LT |
221 | |
222 | /* Default to using normal stack */ | |
65ea5b03 | 223 | sp = regs->sp; |
1da177e4 | 224 | |
83bd0102 RM |
225 | /* |
226 | * If we are on the alternate signal stack and would overflow it, don't. | |
227 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
228 | */ | |
65ea5b03 | 229 | if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size))) |
83bd0102 RM |
230 | return (void __user *) -1L; |
231 | ||
1da177e4 LT |
232 | /* This is the X/Open sanctioned signal stack switching. */ |
233 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
65ea5b03 PA |
234 | if (sas_ss_flags(sp) == 0) |
235 | sp = current->sas_ss_sp + current->sas_ss_size; | |
7e907f48 IM |
236 | } else { |
237 | /* This is the legacy signal stack switching. */ | |
238 | if ((regs->ss & 0xffff) != __USER_DS && | |
239 | !(ka->sa.sa_flags & SA_RESTORER) && | |
240 | ka->sa.sa_restorer) | |
241 | sp = (unsigned long) ka->sa.sa_restorer; | |
1da177e4 LT |
242 | } |
243 | ||
3c1c7f10 SS |
244 | if (used_math()) { |
245 | sp = sp - sig_xstate_size; | |
246 | *fpstate = (struct _fpstate *) sp; | |
4b33669e HS |
247 | if (save_i387_xstate(*fpstate) < 0) |
248 | return (void __user *)-1L; | |
3c1c7f10 SS |
249 | } |
250 | ||
65ea5b03 | 251 | sp -= frame_size; |
7e907f48 IM |
252 | /* |
253 | * Align the stack pointer according to the i386 ABI, | |
254 | * i.e. so that on function entry ((sp + 4) & 15) == 0. | |
255 | */ | |
65ea5b03 | 256 | sp = ((sp + 4) & -16ul) - 4; |
7e907f48 | 257 | |
65ea5b03 | 258 | return (void __user *) sp; |
1da177e4 LT |
259 | } |
260 | ||
7e907f48 | 261 | static int |
1d13024e HS |
262 | __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, |
263 | struct pt_regs *regs) | |
1da177e4 | 264 | { |
1da177e4 | 265 | struct sigframe __user *frame; |
7e907f48 | 266 | void __user *restorer; |
1da177e4 | 267 | int err = 0; |
ab513701 | 268 | void __user *fpstate = NULL; |
1da177e4 | 269 | |
3c1c7f10 | 270 | frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
271 | |
272 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 273 | return -EFAULT; |
1da177e4 | 274 | |
2ba48e16 | 275 | if (__put_user(sig, &frame->sig)) |
3d0aedd9 | 276 | return -EFAULT; |
1da177e4 | 277 | |
2ba48e16 | 278 | if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0])) |
3d0aedd9 | 279 | return -EFAULT; |
1da177e4 LT |
280 | |
281 | if (_NSIG_WORDS > 1) { | |
2ba48e16 HS |
282 | if (__copy_to_user(&frame->extramask, &set->sig[1], |
283 | sizeof(frame->extramask))) | |
3d0aedd9 | 284 | return -EFAULT; |
1da177e4 LT |
285 | } |
286 | ||
1a3e4ca4 | 287 | if (current->mm->context.vdso) |
6c3652ef | 288 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn); |
9fbbd4dd | 289 | else |
ade1af77 | 290 | restorer = &frame->retcode; |
1da177e4 LT |
291 | if (ka->sa.sa_flags & SA_RESTORER) |
292 | restorer = ka->sa.sa_restorer; | |
293 | ||
294 | /* Set up to return from userspace. */ | |
295 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 296 | |
1da177e4 | 297 | /* |
7e907f48 | 298 | * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 |
1da177e4 LT |
299 | * |
300 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
301 | * reasons and because gdb uses it as a signature to notice | |
302 | * signal handler stack frames. | |
303 | */ | |
4a612048 | 304 | err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode); |
1da177e4 LT |
305 | |
306 | if (err) | |
3d0aedd9 | 307 | return -EFAULT; |
1da177e4 LT |
308 | |
309 | /* Set up registers for signal handler */ | |
7e907f48 IM |
310 | regs->sp = (unsigned long)frame; |
311 | regs->ip = (unsigned long)ka->sa.sa_handler; | |
312 | regs->ax = (unsigned long)sig; | |
92bc2056 HH |
313 | regs->dx = 0; |
314 | regs->cx = 0; | |
1da177e4 | 315 | |
65ea5b03 PA |
316 | regs->ds = __USER_DS; |
317 | regs->es = __USER_DS; | |
318 | regs->ss = __USER_DS; | |
319 | regs->cs = __USER_CS; | |
1da177e4 | 320 | |
283828f3 | 321 | return 0; |
1da177e4 LT |
322 | } |
323 | ||
1d13024e HS |
324 | static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
325 | sigset_t *set, struct pt_regs *regs) | |
1da177e4 | 326 | { |
1da177e4 | 327 | struct rt_sigframe __user *frame; |
7e907f48 | 328 | void __user *restorer; |
1da177e4 | 329 | int err = 0; |
ab513701 | 330 | void __user *fpstate = NULL; |
1da177e4 | 331 | |
3c1c7f10 | 332 | frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
333 | |
334 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 335 | return -EFAULT; |
1da177e4 | 336 | |
98e3d45e HS |
337 | put_user_try { |
338 | put_user_ex(sig, &frame->sig); | |
339 | put_user_ex(&frame->info, &frame->pinfo); | |
340 | put_user_ex(&frame->uc, &frame->puc); | |
341 | err |= copy_siginfo_to_user(&frame->info, info); | |
342 | ||
343 | /* Create the ucontext. */ | |
344 | if (cpu_has_xsave) | |
345 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
346 | else | |
347 | put_user_ex(0, &frame->uc.uc_flags); | |
348 | put_user_ex(0, &frame->uc.uc_link); | |
349 | put_user_ex(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
350 | put_user_ex(sas_ss_flags(regs->sp), | |
351 | &frame->uc.uc_stack.ss_flags); | |
352 | put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
353 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, | |
354 | regs, set->sig[0]); | |
355 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
356 | ||
357 | /* Set up to return from userspace. */ | |
358 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn); | |
359 | if (ka->sa.sa_flags & SA_RESTORER) | |
360 | restorer = ka->sa.sa_restorer; | |
361 | put_user_ex(restorer, &frame->pretcode); | |
362 | ||
363 | /* | |
364 | * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 | |
365 | * | |
366 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
367 | * reasons and because gdb uses it as a signature to notice | |
368 | * signal handler stack frames. | |
369 | */ | |
370 | put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode); | |
371 | } put_user_catch(err); | |
1da177e4 LT |
372 | |
373 | if (err) | |
3d0aedd9 | 374 | return -EFAULT; |
1da177e4 LT |
375 | |
376 | /* Set up registers for signal handler */ | |
7e907f48 IM |
377 | regs->sp = (unsigned long)frame; |
378 | regs->ip = (unsigned long)ka->sa.sa_handler; | |
13ad7725 | 379 | regs->ax = (unsigned long)sig; |
7e907f48 IM |
380 | regs->dx = (unsigned long)&frame->info; |
381 | regs->cx = (unsigned long)&frame->uc; | |
1da177e4 | 382 | |
65ea5b03 PA |
383 | regs->ds = __USER_DS; |
384 | regs->es = __USER_DS; | |
385 | regs->ss = __USER_DS; | |
386 | regs->cs = __USER_CS; | |
1da177e4 | 387 | |
283828f3 | 388 | return 0; |
1da177e4 | 389 | } |
bfeb91a9 HS |
390 | #else /* !CONFIG_X86_32 */ |
391 | /* | |
392 | * Determine which stack to use.. | |
393 | */ | |
394 | static void __user * | |
395 | get_stack(struct k_sigaction *ka, unsigned long sp, unsigned long size) | |
396 | { | |
397 | /* Default to using normal stack - redzone*/ | |
398 | sp -= 128; | |
399 | ||
400 | /* This is the X/Open sanctioned signal stack switching. */ | |
401 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
402 | if (sas_ss_flags(sp) == 0) | |
403 | sp = current->sas_ss_sp + current->sas_ss_size; | |
404 | } | |
405 | ||
406 | return (void __user *)round_down(sp - size, 64); | |
407 | } | |
408 | ||
409 | static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
410 | sigset_t *set, struct pt_regs *regs) | |
411 | { | |
412 | struct rt_sigframe __user *frame; | |
413 | void __user *fp = NULL; | |
414 | int err = 0; | |
415 | struct task_struct *me = current; | |
416 | ||
417 | if (used_math()) { | |
418 | fp = get_stack(ka, regs->sp, sig_xstate_size); | |
419 | frame = (void __user *)round_down( | |
420 | (unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8; | |
421 | ||
422 | if (save_i387_xstate(fp) < 0) | |
423 | return -EFAULT; | |
424 | } else | |
425 | frame = get_stack(ka, regs->sp, sizeof(struct rt_sigframe)) - 8; | |
426 | ||
427 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
428 | return -EFAULT; | |
429 | ||
430 | if (ka->sa.sa_flags & SA_SIGINFO) { | |
431 | if (copy_siginfo_to_user(&frame->info, info)) | |
432 | return -EFAULT; | |
433 | } | |
434 | ||
98e3d45e HS |
435 | put_user_try { |
436 | /* Create the ucontext. */ | |
437 | if (cpu_has_xsave) | |
438 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
439 | else | |
440 | put_user_ex(0, &frame->uc.uc_flags); | |
441 | put_user_ex(0, &frame->uc.uc_link); | |
442 | put_user_ex(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
443 | put_user_ex(sas_ss_flags(regs->sp), | |
444 | &frame->uc.uc_stack.ss_flags); | |
445 | put_user_ex(me->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
446 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]); | |
447 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
448 | ||
449 | /* Set up to return from userspace. If provided, use a stub | |
450 | already in userspace. */ | |
451 | /* x86-64 should always use SA_RESTORER. */ | |
452 | if (ka->sa.sa_flags & SA_RESTORER) { | |
453 | put_user_ex(ka->sa.sa_restorer, &frame->pretcode); | |
454 | } else { | |
455 | /* could use a vstub here */ | |
456 | err |= -EFAULT; | |
457 | } | |
458 | } put_user_catch(err); | |
bfeb91a9 HS |
459 | |
460 | if (err) | |
461 | return -EFAULT; | |
462 | ||
463 | /* Set up registers for signal handler */ | |
464 | regs->di = sig; | |
465 | /* In case the signal handler was declared without prototypes */ | |
466 | regs->ax = 0; | |
467 | ||
468 | /* This also works for non SA_SIGINFO handlers because they expect the | |
469 | next argument after the signal number on the stack. */ | |
470 | regs->si = (unsigned long)&frame->info; | |
471 | regs->dx = (unsigned long)&frame->uc; | |
472 | regs->ip = (unsigned long) ka->sa.sa_handler; | |
473 | ||
474 | regs->sp = (unsigned long)frame; | |
475 | ||
476 | /* Set up the CS register to run signal handlers in 64-bit mode, | |
477 | even if the handler happens to be interrupting 32-bit code. */ | |
478 | regs->cs = __USER_CS; | |
479 | ||
480 | return 0; | |
481 | } | |
482 | #endif /* CONFIG_X86_32 */ | |
483 | ||
e5fa2d06 | 484 | #ifdef CONFIG_X86_32 |
bfeb91a9 HS |
485 | /* |
486 | * Atomically swap in the new signal mask, and wait for a signal. | |
487 | */ | |
488 | asmlinkage int | |
489 | sys_sigsuspend(int history0, int history1, old_sigset_t mask) | |
490 | { | |
491 | mask &= _BLOCKABLE; | |
492 | spin_lock_irq(¤t->sighand->siglock); | |
493 | current->saved_sigmask = current->blocked; | |
494 | siginitset(¤t->blocked, mask); | |
495 | recalc_sigpending(); | |
496 | spin_unlock_irq(¤t->sighand->siglock); | |
497 | ||
498 | current->state = TASK_INTERRUPTIBLE; | |
499 | schedule(); | |
500 | set_restore_sigmask(); | |
501 | ||
502 | return -ERESTARTNOHAND; | |
503 | } | |
504 | ||
505 | asmlinkage int | |
506 | sys_sigaction(int sig, const struct old_sigaction __user *act, | |
507 | struct old_sigaction __user *oact) | |
508 | { | |
509 | struct k_sigaction new_ka, old_ka; | |
98e3d45e | 510 | int ret = 0; |
bfeb91a9 HS |
511 | |
512 | if (act) { | |
513 | old_sigset_t mask; | |
514 | ||
98e3d45e | 515 | if (!access_ok(VERIFY_READ, act, sizeof(*act))) |
bfeb91a9 HS |
516 | return -EFAULT; |
517 | ||
98e3d45e HS |
518 | get_user_try { |
519 | get_user_ex(new_ka.sa.sa_handler, &act->sa_handler); | |
520 | get_user_ex(new_ka.sa.sa_flags, &act->sa_flags); | |
521 | get_user_ex(mask, &act->sa_mask); | |
522 | get_user_ex(new_ka.sa.sa_restorer, &act->sa_restorer); | |
523 | } get_user_catch(ret); | |
524 | ||
525 | if (ret) | |
526 | return -EFAULT; | |
bfeb91a9 HS |
527 | siginitset(&new_ka.sa.sa_mask, mask); |
528 | } | |
529 | ||
530 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
531 | ||
532 | if (!ret && oact) { | |
98e3d45e | 533 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact))) |
bfeb91a9 HS |
534 | return -EFAULT; |
535 | ||
98e3d45e HS |
536 | put_user_try { |
537 | put_user_ex(old_ka.sa.sa_handler, &oact->sa_handler); | |
538 | put_user_ex(old_ka.sa.sa_flags, &oact->sa_flags); | |
539 | put_user_ex(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
540 | put_user_ex(old_ka.sa.sa_restorer, &oact->sa_restorer); | |
541 | } put_user_catch(ret); | |
542 | ||
543 | if (ret) | |
544 | return -EFAULT; | |
bfeb91a9 HS |
545 | } |
546 | ||
547 | return ret; | |
548 | } | |
e5fa2d06 | 549 | #endif /* CONFIG_X86_32 */ |
bfeb91a9 HS |
550 | |
551 | #ifdef CONFIG_X86_32 | |
552 | asmlinkage int sys_sigaltstack(unsigned long bx) | |
553 | { | |
554 | /* | |
555 | * This is needed to make gcc realize it doesn't own the | |
556 | * "struct pt_regs" | |
557 | */ | |
558 | struct pt_regs *regs = (struct pt_regs *)&bx; | |
559 | const stack_t __user *uss = (const stack_t __user *)bx; | |
560 | stack_t __user *uoss = (stack_t __user *)regs->cx; | |
561 | ||
562 | return do_sigaltstack(uss, uoss, regs->sp); | |
563 | } | |
564 | #else /* !CONFIG_X86_32 */ | |
565 | asmlinkage long | |
566 | sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, | |
567 | struct pt_regs *regs) | |
568 | { | |
569 | return do_sigaltstack(uss, uoss, regs->sp); | |
570 | } | |
571 | #endif /* CONFIG_X86_32 */ | |
572 | ||
573 | /* | |
574 | * Do a signal return; undo the signal stack. | |
575 | */ | |
e5fa2d06 | 576 | #ifdef CONFIG_X86_32 |
bfeb91a9 HS |
577 | asmlinkage unsigned long sys_sigreturn(unsigned long __unused) |
578 | { | |
579 | struct sigframe __user *frame; | |
580 | struct pt_regs *regs; | |
581 | unsigned long ax; | |
582 | sigset_t set; | |
583 | ||
584 | regs = (struct pt_regs *) &__unused; | |
585 | frame = (struct sigframe __user *)(regs->sp - 8); | |
586 | ||
587 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
588 | goto badframe; | |
589 | if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1 | |
590 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
591 | sizeof(frame->extramask)))) | |
592 | goto badframe; | |
593 | ||
594 | sigdelsetmask(&set, ~_BLOCKABLE); | |
595 | spin_lock_irq(¤t->sighand->siglock); | |
596 | current->blocked = set; | |
597 | recalc_sigpending(); | |
598 | spin_unlock_irq(¤t->sighand->siglock); | |
599 | ||
600 | if (restore_sigcontext(regs, &frame->sc, &ax)) | |
601 | goto badframe; | |
602 | return ax; | |
603 | ||
604 | badframe: | |
ae417bb4 | 605 | signal_fault(regs, frame, "sigreturn"); |
bfeb91a9 HS |
606 | |
607 | return 0; | |
608 | } | |
e5fa2d06 | 609 | #endif /* CONFIG_X86_32 */ |
bfeb91a9 HS |
610 | |
611 | static long do_rt_sigreturn(struct pt_regs *regs) | |
612 | { | |
613 | struct rt_sigframe __user *frame; | |
614 | unsigned long ax; | |
615 | sigset_t set; | |
616 | ||
617 | frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); | |
618 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
619 | goto badframe; | |
620 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
621 | goto badframe; | |
622 | ||
623 | sigdelsetmask(&set, ~_BLOCKABLE); | |
624 | spin_lock_irq(¤t->sighand->siglock); | |
625 | current->blocked = set; | |
626 | recalc_sigpending(); | |
627 | spin_unlock_irq(¤t->sighand->siglock); | |
628 | ||
629 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) | |
630 | goto badframe; | |
631 | ||
632 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT) | |
633 | goto badframe; | |
634 | ||
635 | return ax; | |
636 | ||
637 | badframe: | |
638 | signal_fault(regs, frame, "rt_sigreturn"); | |
639 | return 0; | |
640 | } | |
641 | ||
642 | #ifdef CONFIG_X86_32 | |
552b8aa4 IM |
643 | /* |
644 | * Note: do not pass in pt_regs directly as with tail-call optimization | |
645 | * GCC will incorrectly stomp on the caller's frame and corrupt user-space | |
646 | * register state: | |
647 | */ | |
648 | asmlinkage int sys_rt_sigreturn(unsigned long __unused) | |
bfeb91a9 | 649 | { |
552b8aa4 IM |
650 | struct pt_regs *regs = (struct pt_regs *)&__unused; |
651 | ||
652 | return do_rt_sigreturn(regs); | |
bfeb91a9 HS |
653 | } |
654 | #else /* !CONFIG_X86_32 */ | |
655 | asmlinkage long sys_rt_sigreturn(struct pt_regs *regs) | |
656 | { | |
657 | return do_rt_sigreturn(regs); | |
658 | } | |
659 | #endif /* CONFIG_X86_32 */ | |
1da177e4 LT |
660 | |
661 | /* | |
7e907f48 IM |
662 | * OK, we're invoking a handler: |
663 | */ | |
8d8c13bd HS |
664 | static int signr_convert(int sig) |
665 | { | |
96bf84b7 | 666 | #ifdef CONFIG_X86_32 |
8d8c13bd HS |
667 | struct thread_info *info = current_thread_info(); |
668 | ||
669 | if (info->exec_domain && info->exec_domain->signal_invmap && sig < 32) | |
670 | return info->exec_domain->signal_invmap[sig]; | |
96bf84b7 | 671 | #endif /* CONFIG_X86_32 */ |
8d8c13bd HS |
672 | return sig; |
673 | } | |
674 | ||
cabf5035 HS |
675 | #ifdef CONFIG_X86_32 |
676 | ||
455edbc4 | 677 | #define is_ia32 1 |
4694d239 HS |
678 | #define ia32_setup_frame __setup_frame |
679 | #define ia32_setup_rt_frame __setup_rt_frame | |
455edbc4 | 680 | |
cabf5035 HS |
681 | #else /* !CONFIG_X86_32 */ |
682 | ||
683 | #ifdef CONFIG_IA32_EMULATION | |
684 | #define is_ia32 test_thread_flag(TIF_IA32) | |
685 | #else /* !CONFIG_IA32_EMULATION */ | |
686 | #define is_ia32 0 | |
687 | #endif /* CONFIG_IA32_EMULATION */ | |
688 | ||
f5223763 HS |
689 | int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
690 | sigset_t *set, struct pt_regs *regs); | |
691 | int ia32_setup_frame(int sig, struct k_sigaction *ka, | |
692 | sigset_t *set, struct pt_regs *regs); | |
693 | ||
cabf5035 HS |
694 | #endif /* CONFIG_X86_32 */ |
695 | ||
1d13024e HS |
696 | static int |
697 | setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
698 | sigset_t *set, struct pt_regs *regs) | |
699 | { | |
8d8c13bd | 700 | int usig = signr_convert(sig); |
1d13024e HS |
701 | int ret; |
702 | ||
703 | /* Set up the stack frame */ | |
455edbc4 HS |
704 | if (is_ia32) { |
705 | if (ka->sa.sa_flags & SA_SIGINFO) | |
4694d239 | 706 | ret = ia32_setup_rt_frame(usig, ka, info, set, regs); |
455edbc4 | 707 | else |
4694d239 | 708 | ret = ia32_setup_frame(usig, ka, set, regs); |
455edbc4 HS |
709 | } else |
710 | ret = __setup_rt_frame(sig, ka, info, set, regs); | |
1d13024e | 711 | |
3d0aedd9 HS |
712 | if (ret) { |
713 | force_sigsegv(sig, current); | |
714 | return -EFAULT; | |
715 | } | |
716 | ||
1d13024e HS |
717 | return ret; |
718 | } | |
719 | ||
7c1def16 | 720 | static int |
1da177e4 | 721 | handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, |
ac66f3fd | 722 | sigset_t *oldset, struct pt_regs *regs) |
1da177e4 | 723 | { |
7c1def16 RM |
724 | int ret; |
725 | ||
1da177e4 | 726 | /* Are we from a system call? */ |
bb57925f | 727 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 728 | /* If so, check system call restarting.. */ |
bb57925f | 729 | switch (syscall_get_error(current, regs)) { |
ac66f3fd HH |
730 | case -ERESTART_RESTARTBLOCK: |
731 | case -ERESTARTNOHAND: | |
732 | regs->ax = -EINTR; | |
733 | break; | |
734 | ||
735 | case -ERESTARTSYS: | |
736 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
65ea5b03 | 737 | regs->ax = -EINTR; |
1da177e4 | 738 | break; |
ac66f3fd HH |
739 | } |
740 | /* fallthrough */ | |
741 | case -ERESTARTNOINTR: | |
742 | regs->ax = regs->orig_ax; | |
743 | regs->ip -= 2; | |
744 | break; | |
1da177e4 LT |
745 | } |
746 | } | |
747 | ||
748 | /* | |
e1f28773 RM |
749 | * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF |
750 | * flag so that register information in the sigcontext is correct. | |
1da177e4 | 751 | */ |
65ea5b03 | 752 | if (unlikely(regs->flags & X86_EFLAGS_TF) && |
e1f28773 | 753 | likely(test_and_clear_thread_flag(TIF_FORCED_TF))) |
65ea5b03 | 754 | regs->flags &= ~X86_EFLAGS_TF; |
1da177e4 | 755 | |
1d13024e | 756 | ret = setup_rt_frame(sig, ka, info, oldset, regs); |
1da177e4 | 757 | |
7e907f48 IM |
758 | if (ret) |
759 | return ret; | |
7c1def16 | 760 | |
86d3237c HS |
761 | #ifdef CONFIG_X86_64 |
762 | /* | |
763 | * This has nothing to do with segment registers, | |
764 | * despite the name. This magic affects uaccess.h | |
765 | * macros' behavior. Reset it to the normal setting. | |
766 | */ | |
767 | set_fs(USER_DS); | |
768 | #endif | |
769 | ||
8b9c5ff3 RM |
770 | /* |
771 | * Clear the direction flag as per the ABI for function entry. | |
772 | */ | |
773 | regs->flags &= ~X86_EFLAGS_DF; | |
774 | ||
775 | /* | |
776 | * Clear TF when entering the signal handler, but | |
777 | * notify any tracer that was single-stepping it. | |
778 | * The tracer may want to single-step inside the | |
779 | * handler too. | |
780 | */ | |
781 | regs->flags &= ~X86_EFLAGS_TF; | |
8b9c5ff3 | 782 | |
7e907f48 IM |
783 | spin_lock_irq(¤t->sighand->siglock); |
784 | sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask); | |
785 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
786 | sigaddset(¤t->blocked, sig); | |
787 | recalc_sigpending(); | |
788 | spin_unlock_irq(¤t->sighand->siglock); | |
789 | ||
36a03308 RM |
790 | tracehook_signal_handler(sig, info, ka, regs, |
791 | test_thread_flag(TIF_SINGLESTEP)); | |
792 | ||
7e907f48 | 793 | return 0; |
1da177e4 LT |
794 | } |
795 | ||
57917752 | 796 | #ifdef CONFIG_X86_32 |
8fcd8e20 | 797 | #define NR_restart_syscall __NR_restart_syscall |
57917752 HS |
798 | #else /* !CONFIG_X86_32 */ |
799 | #define NR_restart_syscall \ | |
800 | test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall | |
801 | #endif /* CONFIG_X86_32 */ | |
802 | ||
1da177e4 LT |
803 | /* |
804 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
805 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
806 | * mistake. | |
807 | */ | |
75604d7f | 808 | static void do_signal(struct pt_regs *regs) |
1da177e4 | 809 | { |
ac66f3fd | 810 | struct k_sigaction ka; |
1da177e4 LT |
811 | siginfo_t info; |
812 | int signr; | |
283828f3 | 813 | sigset_t *oldset; |
1da177e4 LT |
814 | |
815 | /* | |
ac66f3fd HH |
816 | * We want the common case to go fast, which is why we may in certain |
817 | * cases get here from kernel mode. Just return without doing anything | |
818 | * if so. | |
819 | * X86_32: vm86 regs switched out by assembly code before reaching | |
820 | * here, so testing against kernel CS suffices. | |
1da177e4 | 821 | */ |
717b594a | 822 | if (!user_mode(regs)) |
283828f3 | 823 | return; |
1da177e4 | 824 | |
5a8da0ea | 825 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) |
283828f3 DH |
826 | oldset = ¤t->saved_sigmask; |
827 | else | |
1da177e4 LT |
828 | oldset = ¤t->blocked; |
829 | ||
830 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
831 | if (signr > 0) { | |
7e907f48 IM |
832 | /* |
833 | * Re-enable any watchpoints before delivering the | |
1da177e4 LT |
834 | * signal to user space. The processor register will |
835 | * have been cleared if the watchpoint triggered | |
836 | * inside the kernel. | |
837 | */ | |
ac66f3fd | 838 | if (current->thread.debugreg7) |
0f534093 | 839 | set_debugreg(current->thread.debugreg7, 7); |
1da177e4 | 840 | |
7e907f48 | 841 | /* Whee! Actually deliver the signal. */ |
283828f3 | 842 | if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { |
7e907f48 | 843 | /* |
5a8da0ea | 844 | * A signal was successfully delivered; the saved |
283828f3 DH |
845 | * sigmask will have been stored in the signal frame, |
846 | * and will be restored by sigreturn, so we can simply | |
5a8da0ea | 847 | * clear the TS_RESTORE_SIGMASK flag. |
7e907f48 | 848 | */ |
5a8da0ea | 849 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; |
283828f3 | 850 | } |
283828f3 | 851 | return; |
1da177e4 LT |
852 | } |
853 | ||
1da177e4 | 854 | /* Did we come from a system call? */ |
bb57925f | 855 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 856 | /* Restart the system call - no handlers present */ |
bb57925f | 857 | switch (syscall_get_error(current, regs)) { |
283828f3 DH |
858 | case -ERESTARTNOHAND: |
859 | case -ERESTARTSYS: | |
860 | case -ERESTARTNOINTR: | |
65ea5b03 PA |
861 | regs->ax = regs->orig_ax; |
862 | regs->ip -= 2; | |
283828f3 DH |
863 | break; |
864 | ||
865 | case -ERESTART_RESTARTBLOCK: | |
8fcd8e20 | 866 | regs->ax = NR_restart_syscall; |
65ea5b03 | 867 | regs->ip -= 2; |
283828f3 | 868 | break; |
1da177e4 LT |
869 | } |
870 | } | |
283828f3 | 871 | |
ac66f3fd HH |
872 | /* |
873 | * If there's no signal to deliver, we just put the saved sigmask | |
874 | * back. | |
875 | */ | |
5a8da0ea RM |
876 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) { |
877 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; | |
283828f3 DH |
878 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); |
879 | } | |
1da177e4 LT |
880 | } |
881 | ||
882 | /* | |
883 | * notification of userspace execution resumption | |
283828f3 | 884 | * - triggered by the TIF_WORK_MASK flags |
1da177e4 | 885 | */ |
7e907f48 IM |
886 | void |
887 | do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) | |
1da177e4 | 888 | { |
ee847c54 HS |
889 | #if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE) |
890 | /* notify userspace of pending MCEs */ | |
891 | if (thread_info_flags & _TIF_MCE_NOTIFY) | |
892 | mce_notify_user(); | |
893 | #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ | |
894 | ||
1da177e4 | 895 | /* deal with pending signal delivery */ |
5a8da0ea | 896 | if (thread_info_flags & _TIF_SIGPENDING) |
283828f3 | 897 | do_signal(regs); |
8f4d37ec | 898 | |
59e52130 RM |
899 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { |
900 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
901 | tracehook_notify_resume(regs); | |
902 | } | |
903 | ||
ee847c54 | 904 | #ifdef CONFIG_X86_32 |
1da177e4 | 905 | clear_thread_flag(TIF_IRET); |
ee847c54 | 906 | #endif /* CONFIG_X86_32 */ |
1da177e4 | 907 | } |
72fa50f4 HS |
908 | |
909 | void signal_fault(struct pt_regs *regs, void __user *frame, char *where) | |
910 | { | |
911 | struct task_struct *me = current; | |
912 | ||
913 | if (show_unhandled_signals && printk_ratelimit()) { | |
ae417bb4 | 914 | printk("%s" |
72fa50f4 | 915 | "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx", |
ae417bb4 | 916 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
72fa50f4 HS |
917 | me->comm, me->pid, where, frame, |
918 | regs->ip, regs->sp, regs->orig_ax); | |
919 | print_vma_addr(" in ", regs->ip); | |
920 | printk(KERN_CONT "\n"); | |
921 | } | |
922 | ||
923 | force_sig(SIGSEGV, me); | |
924 | } |