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 | ||
2601657d | 53 | #define COPY(x) { \ |
98e3d45e | 54 | get_user_ex(regs->x, &sc->x); \ |
2601657d HS |
55 | } |
56 | ||
57 | #define COPY_SEG(seg) { \ | |
58 | unsigned short tmp; \ | |
98e3d45e | 59 | get_user_ex(tmp, &sc->seg); \ |
2601657d HS |
60 | regs->seg = tmp; \ |
61 | } | |
62 | ||
63 | #define COPY_SEG_CPL3(seg) { \ | |
64 | unsigned short tmp; \ | |
98e3d45e | 65 | get_user_ex(tmp, &sc->seg); \ |
2601657d HS |
66 | regs->seg = tmp | 3; \ |
67 | } | |
68 | ||
69 | #define GET_SEG(seg) { \ | |
70 | unsigned short tmp; \ | |
98e3d45e | 71 | get_user_ex(tmp, &sc->seg); \ |
2601657d HS |
72 | loadsegment(seg, tmp); \ |
73 | } | |
74 | ||
75 | static int | |
76 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, | |
77 | unsigned long *pax) | |
78 | { | |
79 | void __user *buf; | |
80 | unsigned int tmpflags; | |
81 | unsigned int err = 0; | |
82 | ||
83 | /* Always make any pending restarted system calls return -EINTR */ | |
84 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
85 | ||
98e3d45e HS |
86 | get_user_try { |
87 | ||
2601657d | 88 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
89 | GET_SEG(gs); |
90 | COPY_SEG(fs); | |
91 | COPY_SEG(es); | |
92 | COPY_SEG(ds); | |
2601657d HS |
93 | #endif /* CONFIG_X86_32 */ |
94 | ||
98e3d45e HS |
95 | COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); |
96 | COPY(dx); COPY(cx); COPY(ip); | |
2601657d HS |
97 | |
98 | #ifdef CONFIG_X86_64 | |
98e3d45e HS |
99 | COPY(r8); |
100 | COPY(r9); | |
101 | COPY(r10); | |
102 | COPY(r11); | |
103 | COPY(r12); | |
104 | COPY(r13); | |
105 | COPY(r14); | |
106 | COPY(r15); | |
2601657d HS |
107 | #endif /* CONFIG_X86_64 */ |
108 | ||
109 | #ifdef CONFIG_X86_32 | |
98e3d45e HS |
110 | COPY_SEG_CPL3(cs); |
111 | COPY_SEG_CPL3(ss); | |
2601657d | 112 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
113 | /* Kernel saves and restores only the CS segment register on signals, |
114 | * which is the bare minimum needed to allow mixed 32/64-bit code. | |
115 | * App's signal handler can save/restore other segments if needed. */ | |
116 | COPY_SEG_CPL3(cs); | |
2601657d HS |
117 | #endif /* CONFIG_X86_32 */ |
118 | ||
98e3d45e HS |
119 | get_user_ex(tmpflags, &sc->flags); |
120 | regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
121 | regs->orig_ax = -1; /* disable syscall checks */ | |
122 | ||
123 | get_user_ex(buf, &sc->fpstate); | |
124 | err |= restore_i387_xstate(buf); | |
2601657d | 125 | |
98e3d45e HS |
126 | get_user_ex(*pax, &sc->ax); |
127 | } get_user_catch(err); | |
2601657d | 128 | |
2601657d HS |
129 | return err; |
130 | } | |
131 | ||
132 | static int | |
133 | setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, | |
134 | struct pt_regs *regs, unsigned long mask) | |
135 | { | |
136 | int err = 0; | |
137 | ||
98e3d45e | 138 | put_user_try { |
2601657d | 139 | |
98e3d45e HS |
140 | #ifdef CONFIG_X86_32 |
141 | { | |
142 | unsigned int tmp; | |
143 | ||
144 | savesegment(gs, tmp); | |
145 | put_user_ex(tmp, (unsigned int __user *)&sc->gs); | |
146 | } | |
147 | put_user_ex(regs->fs, (unsigned int __user *)&sc->fs); | |
148 | put_user_ex(regs->es, (unsigned int __user *)&sc->es); | |
149 | put_user_ex(regs->ds, (unsigned int __user *)&sc->ds); | |
2601657d HS |
150 | #endif /* CONFIG_X86_32 */ |
151 | ||
98e3d45e HS |
152 | put_user_ex(regs->di, &sc->di); |
153 | put_user_ex(regs->si, &sc->si); | |
154 | put_user_ex(regs->bp, &sc->bp); | |
155 | put_user_ex(regs->sp, &sc->sp); | |
156 | put_user_ex(regs->bx, &sc->bx); | |
157 | put_user_ex(regs->dx, &sc->dx); | |
158 | put_user_ex(regs->cx, &sc->cx); | |
159 | put_user_ex(regs->ax, &sc->ax); | |
2601657d | 160 | #ifdef CONFIG_X86_64 |
98e3d45e HS |
161 | put_user_ex(regs->r8, &sc->r8); |
162 | put_user_ex(regs->r9, &sc->r9); | |
163 | put_user_ex(regs->r10, &sc->r10); | |
164 | put_user_ex(regs->r11, &sc->r11); | |
165 | put_user_ex(regs->r12, &sc->r12); | |
166 | put_user_ex(regs->r13, &sc->r13); | |
167 | put_user_ex(regs->r14, &sc->r14); | |
168 | put_user_ex(regs->r15, &sc->r15); | |
2601657d HS |
169 | #endif /* CONFIG_X86_64 */ |
170 | ||
98e3d45e HS |
171 | put_user_ex(current->thread.trap_no, &sc->trapno); |
172 | put_user_ex(current->thread.error_code, &sc->err); | |
173 | put_user_ex(regs->ip, &sc->ip); | |
2601657d | 174 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
175 | put_user_ex(regs->cs, (unsigned int __user *)&sc->cs); |
176 | put_user_ex(regs->flags, &sc->flags); | |
177 | put_user_ex(regs->sp, &sc->sp_at_signal); | |
178 | put_user_ex(regs->ss, (unsigned int __user *)&sc->ss); | |
2601657d | 179 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
180 | put_user_ex(regs->flags, &sc->flags); |
181 | put_user_ex(regs->cs, &sc->cs); | |
182 | put_user_ex(0, &sc->gs); | |
183 | put_user_ex(0, &sc->fs); | |
2601657d HS |
184 | #endif /* CONFIG_X86_32 */ |
185 | ||
98e3d45e | 186 | put_user_ex(fpstate, &sc->fpstate); |
2601657d | 187 | |
98e3d45e HS |
188 | /* non-iBCS2 extensions.. */ |
189 | put_user_ex(mask, &sc->oldmask); | |
190 | put_user_ex(current->thread.cr2, &sc->cr2); | |
191 | } put_user_catch(err); | |
2601657d HS |
192 | |
193 | return err; | |
194 | } | |
195 | ||
1da177e4 | 196 | /* |
bfeb91a9 | 197 | * Set up a signal frame. |
1da177e4 | 198 | */ |
2456d738 | 199 | #ifdef CONFIG_X86_32 |
bfeb91a9 HS |
200 | static const struct { |
201 | u16 poplmovl; | |
202 | u32 val; | |
203 | u16 int80; | |
204 | } __attribute__((packed)) retcode = { | |
205 | 0xb858, /* popl %eax; movl $..., %eax */ | |
206 | __NR_sigreturn, | |
207 | 0x80cd, /* int $0x80 */ | |
208 | }; | |
e6babb6b | 209 | |
bfeb91a9 HS |
210 | static const struct { |
211 | u8 movl; | |
212 | u32 val; | |
213 | u16 int80; | |
214 | u8 pad; | |
215 | } __attribute__((packed)) rt_retcode = { | |
216 | 0xb8, /* movl $..., %eax */ | |
217 | __NR_rt_sigreturn, | |
218 | 0x80cd, /* int $0x80 */ | |
219 | 0 | |
220 | }; | |
1da177e4 LT |
221 | |
222 | /* | |
223 | * Determine which stack to use.. | |
224 | */ | |
225 | static inline void __user * | |
3c1c7f10 | 226 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, |
ab513701 | 227 | void **fpstate) |
1da177e4 | 228 | { |
65ea5b03 | 229 | unsigned long sp; |
1da177e4 LT |
230 | |
231 | /* Default to using normal stack */ | |
65ea5b03 | 232 | sp = regs->sp; |
1da177e4 | 233 | |
83bd0102 RM |
234 | /* |
235 | * If we are on the alternate signal stack and would overflow it, don't. | |
236 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
237 | */ | |
65ea5b03 | 238 | if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size))) |
83bd0102 RM |
239 | return (void __user *) -1L; |
240 | ||
1da177e4 LT |
241 | /* This is the X/Open sanctioned signal stack switching. */ |
242 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
65ea5b03 PA |
243 | if (sas_ss_flags(sp) == 0) |
244 | sp = current->sas_ss_sp + current->sas_ss_size; | |
7e907f48 IM |
245 | } else { |
246 | /* This is the legacy signal stack switching. */ | |
247 | if ((regs->ss & 0xffff) != __USER_DS && | |
248 | !(ka->sa.sa_flags & SA_RESTORER) && | |
249 | ka->sa.sa_restorer) | |
250 | sp = (unsigned long) ka->sa.sa_restorer; | |
1da177e4 LT |
251 | } |
252 | ||
3c1c7f10 SS |
253 | if (used_math()) { |
254 | sp = sp - sig_xstate_size; | |
255 | *fpstate = (struct _fpstate *) sp; | |
4b33669e HS |
256 | if (save_i387_xstate(*fpstate) < 0) |
257 | return (void __user *)-1L; | |
3c1c7f10 SS |
258 | } |
259 | ||
65ea5b03 | 260 | sp -= frame_size; |
7e907f48 IM |
261 | /* |
262 | * Align the stack pointer according to the i386 ABI, | |
263 | * i.e. so that on function entry ((sp + 4) & 15) == 0. | |
264 | */ | |
65ea5b03 | 265 | sp = ((sp + 4) & -16ul) - 4; |
7e907f48 | 266 | |
65ea5b03 | 267 | return (void __user *) sp; |
1da177e4 LT |
268 | } |
269 | ||
7e907f48 | 270 | static int |
1d13024e HS |
271 | __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, |
272 | struct pt_regs *regs) | |
1da177e4 | 273 | { |
1da177e4 | 274 | struct sigframe __user *frame; |
7e907f48 | 275 | void __user *restorer; |
1da177e4 | 276 | int err = 0; |
ab513701 | 277 | void __user *fpstate = NULL; |
1da177e4 | 278 | |
3c1c7f10 | 279 | frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
280 | |
281 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 282 | return -EFAULT; |
1da177e4 | 283 | |
2ba48e16 | 284 | if (__put_user(sig, &frame->sig)) |
3d0aedd9 | 285 | return -EFAULT; |
1da177e4 | 286 | |
2ba48e16 | 287 | if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0])) |
3d0aedd9 | 288 | return -EFAULT; |
1da177e4 LT |
289 | |
290 | if (_NSIG_WORDS > 1) { | |
2ba48e16 HS |
291 | if (__copy_to_user(&frame->extramask, &set->sig[1], |
292 | sizeof(frame->extramask))) | |
3d0aedd9 | 293 | return -EFAULT; |
1da177e4 LT |
294 | } |
295 | ||
1a3e4ca4 | 296 | if (current->mm->context.vdso) |
6c3652ef | 297 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn); |
9fbbd4dd | 298 | else |
ade1af77 | 299 | restorer = &frame->retcode; |
1da177e4 LT |
300 | if (ka->sa.sa_flags & SA_RESTORER) |
301 | restorer = ka->sa.sa_restorer; | |
302 | ||
303 | /* Set up to return from userspace. */ | |
304 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 305 | |
1da177e4 | 306 | /* |
7e907f48 | 307 | * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 |
1da177e4 LT |
308 | * |
309 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
310 | * reasons and because gdb uses it as a signature to notice | |
311 | * signal handler stack frames. | |
312 | */ | |
4a612048 | 313 | err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode); |
1da177e4 LT |
314 | |
315 | if (err) | |
3d0aedd9 | 316 | return -EFAULT; |
1da177e4 LT |
317 | |
318 | /* Set up registers for signal handler */ | |
7e907f48 IM |
319 | regs->sp = (unsigned long)frame; |
320 | regs->ip = (unsigned long)ka->sa.sa_handler; | |
321 | regs->ax = (unsigned long)sig; | |
92bc2056 HH |
322 | regs->dx = 0; |
323 | regs->cx = 0; | |
1da177e4 | 324 | |
65ea5b03 PA |
325 | regs->ds = __USER_DS; |
326 | regs->es = __USER_DS; | |
327 | regs->ss = __USER_DS; | |
328 | regs->cs = __USER_CS; | |
1da177e4 | 329 | |
283828f3 | 330 | return 0; |
1da177e4 LT |
331 | } |
332 | ||
1d13024e HS |
333 | static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
334 | sigset_t *set, struct pt_regs *regs) | |
1da177e4 | 335 | { |
1da177e4 | 336 | struct rt_sigframe __user *frame; |
7e907f48 | 337 | void __user *restorer; |
1da177e4 | 338 | int err = 0; |
ab513701 | 339 | void __user *fpstate = NULL; |
1da177e4 | 340 | |
3c1c7f10 | 341 | frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
342 | |
343 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 344 | return -EFAULT; |
1da177e4 | 345 | |
98e3d45e HS |
346 | put_user_try { |
347 | put_user_ex(sig, &frame->sig); | |
348 | put_user_ex(&frame->info, &frame->pinfo); | |
349 | put_user_ex(&frame->uc, &frame->puc); | |
350 | err |= copy_siginfo_to_user(&frame->info, info); | |
351 | ||
352 | /* Create the ucontext. */ | |
353 | if (cpu_has_xsave) | |
354 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
355 | else | |
356 | put_user_ex(0, &frame->uc.uc_flags); | |
357 | put_user_ex(0, &frame->uc.uc_link); | |
358 | put_user_ex(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
359 | put_user_ex(sas_ss_flags(regs->sp), | |
360 | &frame->uc.uc_stack.ss_flags); | |
361 | put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
362 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, | |
363 | regs, set->sig[0]); | |
364 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
365 | ||
366 | /* Set up to return from userspace. */ | |
367 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn); | |
368 | if (ka->sa.sa_flags & SA_RESTORER) | |
369 | restorer = ka->sa.sa_restorer; | |
370 | put_user_ex(restorer, &frame->pretcode); | |
371 | ||
372 | /* | |
373 | * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 | |
374 | * | |
375 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
376 | * reasons and because gdb uses it as a signature to notice | |
377 | * signal handler stack frames. | |
378 | */ | |
379 | put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode); | |
380 | } put_user_catch(err); | |
1da177e4 LT |
381 | |
382 | if (err) | |
3d0aedd9 | 383 | return -EFAULT; |
1da177e4 LT |
384 | |
385 | /* Set up registers for signal handler */ | |
7e907f48 IM |
386 | regs->sp = (unsigned long)frame; |
387 | regs->ip = (unsigned long)ka->sa.sa_handler; | |
13ad7725 | 388 | regs->ax = (unsigned long)sig; |
7e907f48 IM |
389 | regs->dx = (unsigned long)&frame->info; |
390 | regs->cx = (unsigned long)&frame->uc; | |
1da177e4 | 391 | |
65ea5b03 PA |
392 | regs->ds = __USER_DS; |
393 | regs->es = __USER_DS; | |
394 | regs->ss = __USER_DS; | |
395 | regs->cs = __USER_CS; | |
1da177e4 | 396 | |
283828f3 | 397 | return 0; |
1da177e4 | 398 | } |
bfeb91a9 HS |
399 | #else /* !CONFIG_X86_32 */ |
400 | /* | |
401 | * Determine which stack to use.. | |
402 | */ | |
403 | static void __user * | |
404 | get_stack(struct k_sigaction *ka, unsigned long sp, unsigned long size) | |
405 | { | |
406 | /* Default to using normal stack - redzone*/ | |
407 | sp -= 128; | |
408 | ||
409 | /* This is the X/Open sanctioned signal stack switching. */ | |
410 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
411 | if (sas_ss_flags(sp) == 0) | |
412 | sp = current->sas_ss_sp + current->sas_ss_size; | |
413 | } | |
414 | ||
415 | return (void __user *)round_down(sp - size, 64); | |
416 | } | |
417 | ||
418 | static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
419 | sigset_t *set, struct pt_regs *regs) | |
420 | { | |
421 | struct rt_sigframe __user *frame; | |
422 | void __user *fp = NULL; | |
423 | int err = 0; | |
424 | struct task_struct *me = current; | |
425 | ||
426 | if (used_math()) { | |
427 | fp = get_stack(ka, regs->sp, sig_xstate_size); | |
428 | frame = (void __user *)round_down( | |
429 | (unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8; | |
430 | ||
431 | if (save_i387_xstate(fp) < 0) | |
432 | return -EFAULT; | |
433 | } else | |
434 | frame = get_stack(ka, regs->sp, sizeof(struct rt_sigframe)) - 8; | |
435 | ||
436 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
437 | return -EFAULT; | |
438 | ||
439 | if (ka->sa.sa_flags & SA_SIGINFO) { | |
440 | if (copy_siginfo_to_user(&frame->info, info)) | |
441 | return -EFAULT; | |
442 | } | |
443 | ||
98e3d45e HS |
444 | put_user_try { |
445 | /* Create the ucontext. */ | |
446 | if (cpu_has_xsave) | |
447 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
448 | else | |
449 | put_user_ex(0, &frame->uc.uc_flags); | |
450 | put_user_ex(0, &frame->uc.uc_link); | |
451 | put_user_ex(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
452 | put_user_ex(sas_ss_flags(regs->sp), | |
453 | &frame->uc.uc_stack.ss_flags); | |
454 | put_user_ex(me->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
455 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]); | |
456 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
457 | ||
458 | /* Set up to return from userspace. If provided, use a stub | |
459 | already in userspace. */ | |
460 | /* x86-64 should always use SA_RESTORER. */ | |
461 | if (ka->sa.sa_flags & SA_RESTORER) { | |
462 | put_user_ex(ka->sa.sa_restorer, &frame->pretcode); | |
463 | } else { | |
464 | /* could use a vstub here */ | |
465 | err |= -EFAULT; | |
466 | } | |
467 | } put_user_catch(err); | |
bfeb91a9 HS |
468 | |
469 | if (err) | |
470 | return -EFAULT; | |
471 | ||
472 | /* Set up registers for signal handler */ | |
473 | regs->di = sig; | |
474 | /* In case the signal handler was declared without prototypes */ | |
475 | regs->ax = 0; | |
476 | ||
477 | /* This also works for non SA_SIGINFO handlers because they expect the | |
478 | next argument after the signal number on the stack. */ | |
479 | regs->si = (unsigned long)&frame->info; | |
480 | regs->dx = (unsigned long)&frame->uc; | |
481 | regs->ip = (unsigned long) ka->sa.sa_handler; | |
482 | ||
483 | regs->sp = (unsigned long)frame; | |
484 | ||
485 | /* Set up the CS register to run signal handlers in 64-bit mode, | |
486 | even if the handler happens to be interrupting 32-bit code. */ | |
487 | regs->cs = __USER_CS; | |
488 | ||
489 | return 0; | |
490 | } | |
491 | #endif /* CONFIG_X86_32 */ | |
492 | ||
e5fa2d06 | 493 | #ifdef CONFIG_X86_32 |
bfeb91a9 HS |
494 | /* |
495 | * Atomically swap in the new signal mask, and wait for a signal. | |
496 | */ | |
497 | asmlinkage int | |
498 | sys_sigsuspend(int history0, int history1, old_sigset_t mask) | |
499 | { | |
500 | mask &= _BLOCKABLE; | |
501 | spin_lock_irq(¤t->sighand->siglock); | |
502 | current->saved_sigmask = current->blocked; | |
503 | siginitset(¤t->blocked, mask); | |
504 | recalc_sigpending(); | |
505 | spin_unlock_irq(¤t->sighand->siglock); | |
506 | ||
507 | current->state = TASK_INTERRUPTIBLE; | |
508 | schedule(); | |
509 | set_restore_sigmask(); | |
510 | ||
511 | return -ERESTARTNOHAND; | |
512 | } | |
513 | ||
514 | asmlinkage int | |
515 | sys_sigaction(int sig, const struct old_sigaction __user *act, | |
516 | struct old_sigaction __user *oact) | |
517 | { | |
518 | struct k_sigaction new_ka, old_ka; | |
98e3d45e | 519 | int ret = 0; |
bfeb91a9 HS |
520 | |
521 | if (act) { | |
522 | old_sigset_t mask; | |
523 | ||
98e3d45e | 524 | if (!access_ok(VERIFY_READ, act, sizeof(*act))) |
bfeb91a9 HS |
525 | return -EFAULT; |
526 | ||
98e3d45e HS |
527 | get_user_try { |
528 | get_user_ex(new_ka.sa.sa_handler, &act->sa_handler); | |
529 | get_user_ex(new_ka.sa.sa_flags, &act->sa_flags); | |
530 | get_user_ex(mask, &act->sa_mask); | |
531 | get_user_ex(new_ka.sa.sa_restorer, &act->sa_restorer); | |
532 | } get_user_catch(ret); | |
533 | ||
534 | if (ret) | |
535 | return -EFAULT; | |
bfeb91a9 HS |
536 | siginitset(&new_ka.sa.sa_mask, mask); |
537 | } | |
538 | ||
539 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
540 | ||
541 | if (!ret && oact) { | |
98e3d45e | 542 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact))) |
bfeb91a9 HS |
543 | return -EFAULT; |
544 | ||
98e3d45e HS |
545 | put_user_try { |
546 | put_user_ex(old_ka.sa.sa_handler, &oact->sa_handler); | |
547 | put_user_ex(old_ka.sa.sa_flags, &oact->sa_flags); | |
548 | put_user_ex(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
549 | put_user_ex(old_ka.sa.sa_restorer, &oact->sa_restorer); | |
550 | } put_user_catch(ret); | |
551 | ||
552 | if (ret) | |
553 | return -EFAULT; | |
bfeb91a9 HS |
554 | } |
555 | ||
556 | return ret; | |
557 | } | |
e5fa2d06 | 558 | #endif /* CONFIG_X86_32 */ |
bfeb91a9 HS |
559 | |
560 | #ifdef CONFIG_X86_32 | |
561 | asmlinkage int sys_sigaltstack(unsigned long bx) | |
562 | { | |
563 | /* | |
564 | * This is needed to make gcc realize it doesn't own the | |
565 | * "struct pt_regs" | |
566 | */ | |
567 | struct pt_regs *regs = (struct pt_regs *)&bx; | |
568 | const stack_t __user *uss = (const stack_t __user *)bx; | |
569 | stack_t __user *uoss = (stack_t __user *)regs->cx; | |
570 | ||
571 | return do_sigaltstack(uss, uoss, regs->sp); | |
572 | } | |
573 | #else /* !CONFIG_X86_32 */ | |
574 | asmlinkage long | |
575 | sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, | |
576 | struct pt_regs *regs) | |
577 | { | |
578 | return do_sigaltstack(uss, uoss, regs->sp); | |
579 | } | |
580 | #endif /* CONFIG_X86_32 */ | |
581 | ||
582 | /* | |
583 | * Do a signal return; undo the signal stack. | |
584 | */ | |
e5fa2d06 | 585 | #ifdef CONFIG_X86_32 |
bfeb91a9 HS |
586 | asmlinkage unsigned long sys_sigreturn(unsigned long __unused) |
587 | { | |
588 | struct sigframe __user *frame; | |
589 | struct pt_regs *regs; | |
590 | unsigned long ax; | |
591 | sigset_t set; | |
592 | ||
593 | regs = (struct pt_regs *) &__unused; | |
594 | frame = (struct sigframe __user *)(regs->sp - 8); | |
595 | ||
596 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
597 | goto badframe; | |
598 | if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1 | |
599 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
600 | sizeof(frame->extramask)))) | |
601 | goto badframe; | |
602 | ||
603 | sigdelsetmask(&set, ~_BLOCKABLE); | |
604 | spin_lock_irq(¤t->sighand->siglock); | |
605 | current->blocked = set; | |
606 | recalc_sigpending(); | |
607 | spin_unlock_irq(¤t->sighand->siglock); | |
608 | ||
609 | if (restore_sigcontext(regs, &frame->sc, &ax)) | |
610 | goto badframe; | |
611 | return ax; | |
612 | ||
613 | badframe: | |
ae417bb4 | 614 | signal_fault(regs, frame, "sigreturn"); |
bfeb91a9 HS |
615 | |
616 | return 0; | |
617 | } | |
e5fa2d06 | 618 | #endif /* CONFIG_X86_32 */ |
bfeb91a9 HS |
619 | |
620 | static long do_rt_sigreturn(struct pt_regs *regs) | |
621 | { | |
622 | struct rt_sigframe __user *frame; | |
623 | unsigned long ax; | |
624 | sigset_t set; | |
625 | ||
626 | frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); | |
627 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
628 | goto badframe; | |
629 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
630 | goto badframe; | |
631 | ||
632 | sigdelsetmask(&set, ~_BLOCKABLE); | |
633 | spin_lock_irq(¤t->sighand->siglock); | |
634 | current->blocked = set; | |
635 | recalc_sigpending(); | |
636 | spin_unlock_irq(¤t->sighand->siglock); | |
637 | ||
638 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) | |
639 | goto badframe; | |
640 | ||
641 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT) | |
642 | goto badframe; | |
643 | ||
644 | return ax; | |
645 | ||
646 | badframe: | |
647 | signal_fault(regs, frame, "rt_sigreturn"); | |
648 | return 0; | |
649 | } | |
650 | ||
651 | #ifdef CONFIG_X86_32 | |
4217458d | 652 | asmlinkage int sys_rt_sigreturn(struct pt_regs regs) |
bfeb91a9 | 653 | { |
4217458d | 654 | return do_rt_sigreturn(®s); |
bfeb91a9 HS |
655 | } |
656 | #else /* !CONFIG_X86_32 */ | |
657 | asmlinkage long sys_rt_sigreturn(struct pt_regs *regs) | |
658 | { | |
659 | return do_rt_sigreturn(regs); | |
660 | } | |
661 | #endif /* CONFIG_X86_32 */ | |
1da177e4 LT |
662 | |
663 | /* | |
7e907f48 IM |
664 | * OK, we're invoking a handler: |
665 | */ | |
8d8c13bd HS |
666 | static int signr_convert(int sig) |
667 | { | |
96bf84b7 | 668 | #ifdef CONFIG_X86_32 |
8d8c13bd HS |
669 | struct thread_info *info = current_thread_info(); |
670 | ||
671 | if (info->exec_domain && info->exec_domain->signal_invmap && sig < 32) | |
672 | return info->exec_domain->signal_invmap[sig]; | |
96bf84b7 | 673 | #endif /* CONFIG_X86_32 */ |
8d8c13bd HS |
674 | return sig; |
675 | } | |
676 | ||
cabf5035 HS |
677 | #ifdef CONFIG_X86_32 |
678 | ||
455edbc4 | 679 | #define is_ia32 1 |
4694d239 HS |
680 | #define ia32_setup_frame __setup_frame |
681 | #define ia32_setup_rt_frame __setup_rt_frame | |
455edbc4 | 682 | |
cabf5035 HS |
683 | #else /* !CONFIG_X86_32 */ |
684 | ||
685 | #ifdef CONFIG_IA32_EMULATION | |
686 | #define is_ia32 test_thread_flag(TIF_IA32) | |
687 | #else /* !CONFIG_IA32_EMULATION */ | |
688 | #define is_ia32 0 | |
689 | #endif /* CONFIG_IA32_EMULATION */ | |
690 | ||
f5223763 HS |
691 | int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
692 | sigset_t *set, struct pt_regs *regs); | |
693 | int ia32_setup_frame(int sig, struct k_sigaction *ka, | |
694 | sigset_t *set, struct pt_regs *regs); | |
695 | ||
cabf5035 HS |
696 | #endif /* CONFIG_X86_32 */ |
697 | ||
1d13024e HS |
698 | static int |
699 | setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
700 | sigset_t *set, struct pt_regs *regs) | |
701 | { | |
8d8c13bd | 702 | int usig = signr_convert(sig); |
1d13024e HS |
703 | int ret; |
704 | ||
705 | /* Set up the stack frame */ | |
455edbc4 HS |
706 | if (is_ia32) { |
707 | if (ka->sa.sa_flags & SA_SIGINFO) | |
4694d239 | 708 | ret = ia32_setup_rt_frame(usig, ka, info, set, regs); |
455edbc4 | 709 | else |
4694d239 | 710 | ret = ia32_setup_frame(usig, ka, set, regs); |
455edbc4 HS |
711 | } else |
712 | ret = __setup_rt_frame(sig, ka, info, set, regs); | |
1d13024e | 713 | |
3d0aedd9 HS |
714 | if (ret) { |
715 | force_sigsegv(sig, current); | |
716 | return -EFAULT; | |
717 | } | |
718 | ||
1d13024e HS |
719 | return ret; |
720 | } | |
721 | ||
7c1def16 | 722 | static int |
1da177e4 | 723 | handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, |
ac66f3fd | 724 | sigset_t *oldset, struct pt_regs *regs) |
1da177e4 | 725 | { |
7c1def16 RM |
726 | int ret; |
727 | ||
1da177e4 | 728 | /* Are we from a system call? */ |
bb57925f | 729 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 730 | /* If so, check system call restarting.. */ |
bb57925f | 731 | switch (syscall_get_error(current, regs)) { |
ac66f3fd HH |
732 | case -ERESTART_RESTARTBLOCK: |
733 | case -ERESTARTNOHAND: | |
734 | regs->ax = -EINTR; | |
735 | break; | |
736 | ||
737 | case -ERESTARTSYS: | |
738 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
65ea5b03 | 739 | regs->ax = -EINTR; |
1da177e4 | 740 | break; |
ac66f3fd HH |
741 | } |
742 | /* fallthrough */ | |
743 | case -ERESTARTNOINTR: | |
744 | regs->ax = regs->orig_ax; | |
745 | regs->ip -= 2; | |
746 | break; | |
1da177e4 LT |
747 | } |
748 | } | |
749 | ||
750 | /* | |
e1f28773 RM |
751 | * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF |
752 | * flag so that register information in the sigcontext is correct. | |
1da177e4 | 753 | */ |
65ea5b03 | 754 | if (unlikely(regs->flags & X86_EFLAGS_TF) && |
e1f28773 | 755 | likely(test_and_clear_thread_flag(TIF_FORCED_TF))) |
65ea5b03 | 756 | regs->flags &= ~X86_EFLAGS_TF; |
1da177e4 | 757 | |
1d13024e | 758 | ret = setup_rt_frame(sig, ka, info, oldset, regs); |
1da177e4 | 759 | |
7e907f48 IM |
760 | if (ret) |
761 | return ret; | |
7c1def16 | 762 | |
86d3237c HS |
763 | #ifdef CONFIG_X86_64 |
764 | /* | |
765 | * This has nothing to do with segment registers, | |
766 | * despite the name. This magic affects uaccess.h | |
767 | * macros' behavior. Reset it to the normal setting. | |
768 | */ | |
769 | set_fs(USER_DS); | |
770 | #endif | |
771 | ||
8b9c5ff3 RM |
772 | /* |
773 | * Clear the direction flag as per the ABI for function entry. | |
774 | */ | |
775 | regs->flags &= ~X86_EFLAGS_DF; | |
776 | ||
777 | /* | |
778 | * Clear TF when entering the signal handler, but | |
779 | * notify any tracer that was single-stepping it. | |
780 | * The tracer may want to single-step inside the | |
781 | * handler too. | |
782 | */ | |
783 | regs->flags &= ~X86_EFLAGS_TF; | |
8b9c5ff3 | 784 | |
7e907f48 IM |
785 | spin_lock_irq(¤t->sighand->siglock); |
786 | sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask); | |
787 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
788 | sigaddset(¤t->blocked, sig); | |
789 | recalc_sigpending(); | |
790 | spin_unlock_irq(¤t->sighand->siglock); | |
791 | ||
36a03308 RM |
792 | tracehook_signal_handler(sig, info, ka, regs, |
793 | test_thread_flag(TIF_SINGLESTEP)); | |
794 | ||
7e907f48 | 795 | return 0; |
1da177e4 LT |
796 | } |
797 | ||
57917752 | 798 | #ifdef CONFIG_X86_32 |
8fcd8e20 | 799 | #define NR_restart_syscall __NR_restart_syscall |
57917752 HS |
800 | #else /* !CONFIG_X86_32 */ |
801 | #define NR_restart_syscall \ | |
802 | test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall | |
803 | #endif /* CONFIG_X86_32 */ | |
804 | ||
1da177e4 LT |
805 | /* |
806 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
807 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
808 | * mistake. | |
809 | */ | |
75604d7f | 810 | static void do_signal(struct pt_regs *regs) |
1da177e4 | 811 | { |
ac66f3fd | 812 | struct k_sigaction ka; |
1da177e4 LT |
813 | siginfo_t info; |
814 | int signr; | |
283828f3 | 815 | sigset_t *oldset; |
1da177e4 LT |
816 | |
817 | /* | |
ac66f3fd HH |
818 | * We want the common case to go fast, which is why we may in certain |
819 | * cases get here from kernel mode. Just return without doing anything | |
820 | * if so. | |
821 | * X86_32: vm86 regs switched out by assembly code before reaching | |
822 | * here, so testing against kernel CS suffices. | |
1da177e4 | 823 | */ |
717b594a | 824 | if (!user_mode(regs)) |
283828f3 | 825 | return; |
1da177e4 | 826 | |
5a8da0ea | 827 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) |
283828f3 DH |
828 | oldset = ¤t->saved_sigmask; |
829 | else | |
1da177e4 LT |
830 | oldset = ¤t->blocked; |
831 | ||
832 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
833 | if (signr > 0) { | |
7e907f48 IM |
834 | /* |
835 | * Re-enable any watchpoints before delivering the | |
1da177e4 LT |
836 | * signal to user space. The processor register will |
837 | * have been cleared if the watchpoint triggered | |
838 | * inside the kernel. | |
839 | */ | |
ac66f3fd | 840 | if (current->thread.debugreg7) |
0f534093 | 841 | set_debugreg(current->thread.debugreg7, 7); |
1da177e4 | 842 | |
7e907f48 | 843 | /* Whee! Actually deliver the signal. */ |
283828f3 | 844 | if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { |
7e907f48 | 845 | /* |
5a8da0ea | 846 | * A signal was successfully delivered; the saved |
283828f3 DH |
847 | * sigmask will have been stored in the signal frame, |
848 | * and will be restored by sigreturn, so we can simply | |
5a8da0ea | 849 | * clear the TS_RESTORE_SIGMASK flag. |
7e907f48 | 850 | */ |
5a8da0ea | 851 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; |
283828f3 | 852 | } |
283828f3 | 853 | return; |
1da177e4 LT |
854 | } |
855 | ||
1da177e4 | 856 | /* Did we come from a system call? */ |
bb57925f | 857 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 858 | /* Restart the system call - no handlers present */ |
bb57925f | 859 | switch (syscall_get_error(current, regs)) { |
283828f3 DH |
860 | case -ERESTARTNOHAND: |
861 | case -ERESTARTSYS: | |
862 | case -ERESTARTNOINTR: | |
65ea5b03 PA |
863 | regs->ax = regs->orig_ax; |
864 | regs->ip -= 2; | |
283828f3 DH |
865 | break; |
866 | ||
867 | case -ERESTART_RESTARTBLOCK: | |
8fcd8e20 | 868 | regs->ax = NR_restart_syscall; |
65ea5b03 | 869 | regs->ip -= 2; |
283828f3 | 870 | break; |
1da177e4 LT |
871 | } |
872 | } | |
283828f3 | 873 | |
ac66f3fd HH |
874 | /* |
875 | * If there's no signal to deliver, we just put the saved sigmask | |
876 | * back. | |
877 | */ | |
5a8da0ea RM |
878 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) { |
879 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; | |
283828f3 DH |
880 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); |
881 | } | |
1da177e4 LT |
882 | } |
883 | ||
884 | /* | |
885 | * notification of userspace execution resumption | |
283828f3 | 886 | * - triggered by the TIF_WORK_MASK flags |
1da177e4 | 887 | */ |
7e907f48 IM |
888 | void |
889 | do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) | |
1da177e4 | 890 | { |
ee847c54 HS |
891 | #if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE) |
892 | /* notify userspace of pending MCEs */ | |
893 | if (thread_info_flags & _TIF_MCE_NOTIFY) | |
894 | mce_notify_user(); | |
895 | #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ | |
896 | ||
1da177e4 | 897 | /* deal with pending signal delivery */ |
5a8da0ea | 898 | if (thread_info_flags & _TIF_SIGPENDING) |
283828f3 | 899 | do_signal(regs); |
8f4d37ec | 900 | |
59e52130 RM |
901 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { |
902 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
903 | tracehook_notify_resume(regs); | |
904 | } | |
905 | ||
ee847c54 | 906 | #ifdef CONFIG_X86_32 |
1da177e4 | 907 | clear_thread_flag(TIF_IRET); |
ee847c54 | 908 | #endif /* CONFIG_X86_32 */ |
1da177e4 | 909 | } |
72fa50f4 HS |
910 | |
911 | void signal_fault(struct pt_regs *regs, void __user *frame, char *where) | |
912 | { | |
913 | struct task_struct *me = current; | |
914 | ||
915 | if (show_unhandled_signals && printk_ratelimit()) { | |
ae417bb4 | 916 | printk("%s" |
72fa50f4 | 917 | "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx", |
ae417bb4 | 918 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
72fa50f4 HS |
919 | me->comm, me->pid, where, frame, |
920 | regs->ip, regs->sp, regs->orig_ax); | |
921 | print_vma_addr(" in ", regs->ip); | |
922 | printk(KERN_CONT "\n"); | |
923 | } | |
924 | ||
925 | force_sig(SIGSEGV, me); | |
926 | } |