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 | 8 | */ |
c767a54b JP |
9 | |
10 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
11 | ||
5c9b3a0c HS |
12 | #include <linux/sched.h> |
13 | #include <linux/mm.h> | |
14 | #include <linux/smp.h> | |
1da177e4 | 15 | #include <linux/kernel.h> |
1da177e4 LT |
16 | #include <linux/errno.h> |
17 | #include <linux/wait.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> | |
7c68af6e | 23 | #include <linux/user-return-notifier.h> |
0326f5a9 | 24 | #include <linux/uprobes.h> |
91d1aa43 | 25 | #include <linux/context_tracking.h> |
7e907f48 | 26 | |
1da177e4 LT |
27 | #include <asm/processor.h> |
28 | #include <asm/ucontext.h> | |
1da177e4 | 29 | #include <asm/i387.h> |
1361b83a | 30 | #include <asm/fpu-internal.h> |
6c3652ef | 31 | #include <asm/vdso.h> |
4efc0670 | 32 | #include <asm/mce.h> |
f28f0c23 | 33 | #include <asm/sighandling.h> |
5c9b3a0c HS |
34 | |
35 | #ifdef CONFIG_X86_64 | |
36 | #include <asm/proto.h> | |
37 | #include <asm/ia32_unistd.h> | |
c5a37394 | 38 | #include <asm/sys_ia32.h> |
5c9b3a0c HS |
39 | #endif /* CONFIG_X86_64 */ |
40 | ||
bb57925f | 41 | #include <asm/syscall.h> |
bbc1f698 | 42 | #include <asm/syscalls.h> |
7e907f48 | 43 | |
41af86fa | 44 | #include <asm/sigframe.h> |
1da177e4 | 45 | |
1a176803 HH |
46 | #ifdef CONFIG_X86_32 |
47 | # define FIX_EFLAGS (__FIX_EFLAGS | X86_EFLAGS_RF) | |
48 | #else | |
49 | # define FIX_EFLAGS __FIX_EFLAGS | |
50 | #endif | |
51 | ||
d9a89a26 TH |
52 | #define COPY(x) do { \ |
53 | get_user_ex(regs->x, &sc->x); \ | |
54 | } while (0) | |
2601657d | 55 | |
d9a89a26 TH |
56 | #define GET_SEG(seg) ({ \ |
57 | unsigned short tmp; \ | |
58 | get_user_ex(tmp, &sc->seg); \ | |
59 | tmp; \ | |
60 | }) | |
2601657d | 61 | |
d9a89a26 TH |
62 | #define COPY_SEG(seg) do { \ |
63 | regs->seg = GET_SEG(seg); \ | |
64 | } while (0) | |
2601657d | 65 | |
d9a89a26 TH |
66 | #define COPY_SEG_CPL3(seg) do { \ |
67 | regs->seg = GET_SEG(seg) | 3; \ | |
68 | } while (0) | |
2601657d | 69 | |
85139422 PA |
70 | int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, |
71 | unsigned long *pax) | |
2601657d HS |
72 | { |
73 | void __user *buf; | |
74 | unsigned int tmpflags; | |
75 | unsigned int err = 0; | |
76 | ||
77 | /* Always make any pending restarted system calls return -EINTR */ | |
78 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
79 | ||
98e3d45e HS |
80 | get_user_try { |
81 | ||
2601657d | 82 | #ifdef CONFIG_X86_32 |
d9a89a26 | 83 | set_user_gs(regs, GET_SEG(gs)); |
98e3d45e HS |
84 | COPY_SEG(fs); |
85 | COPY_SEG(es); | |
86 | COPY_SEG(ds); | |
2601657d HS |
87 | #endif /* CONFIG_X86_32 */ |
88 | ||
98e3d45e HS |
89 | COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); |
90 | COPY(dx); COPY(cx); COPY(ip); | |
2601657d HS |
91 | |
92 | #ifdef CONFIG_X86_64 | |
98e3d45e HS |
93 | COPY(r8); |
94 | COPY(r9); | |
95 | COPY(r10); | |
96 | COPY(r11); | |
97 | COPY(r12); | |
98 | COPY(r13); | |
99 | COPY(r14); | |
100 | COPY(r15); | |
2601657d HS |
101 | #endif /* CONFIG_X86_64 */ |
102 | ||
103 | #ifdef CONFIG_X86_32 | |
98e3d45e HS |
104 | COPY_SEG_CPL3(cs); |
105 | COPY_SEG_CPL3(ss); | |
2601657d | 106 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
107 | /* Kernel saves and restores only the CS segment register on signals, |
108 | * which is the bare minimum needed to allow mixed 32/64-bit code. | |
109 | * App's signal handler can save/restore other segments if needed. */ | |
110 | COPY_SEG_CPL3(cs); | |
2601657d HS |
111 | #endif /* CONFIG_X86_32 */ |
112 | ||
98e3d45e HS |
113 | get_user_ex(tmpflags, &sc->flags); |
114 | regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
115 | regs->orig_ax = -1; /* disable syscall checks */ | |
116 | ||
117 | get_user_ex(buf, &sc->fpstate); | |
2601657d | 118 | |
98e3d45e HS |
119 | get_user_ex(*pax, &sc->ax); |
120 | } get_user_catch(err); | |
2601657d | 121 | |
49b8c695 | 122 | err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32)); |
5e88353d | 123 | |
2601657d HS |
124 | return err; |
125 | } | |
126 | ||
85139422 PA |
127 | int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, |
128 | struct pt_regs *regs, unsigned long mask) | |
2601657d HS |
129 | { |
130 | int err = 0; | |
131 | ||
98e3d45e | 132 | put_user_try { |
2601657d | 133 | |
98e3d45e | 134 | #ifdef CONFIG_X86_32 |
d9a89a26 | 135 | put_user_ex(get_user_gs(regs), (unsigned int __user *)&sc->gs); |
98e3d45e HS |
136 | put_user_ex(regs->fs, (unsigned int __user *)&sc->fs); |
137 | put_user_ex(regs->es, (unsigned int __user *)&sc->es); | |
138 | put_user_ex(regs->ds, (unsigned int __user *)&sc->ds); | |
2601657d HS |
139 | #endif /* CONFIG_X86_32 */ |
140 | ||
98e3d45e HS |
141 | put_user_ex(regs->di, &sc->di); |
142 | put_user_ex(regs->si, &sc->si); | |
143 | put_user_ex(regs->bp, &sc->bp); | |
144 | put_user_ex(regs->sp, &sc->sp); | |
145 | put_user_ex(regs->bx, &sc->bx); | |
146 | put_user_ex(regs->dx, &sc->dx); | |
147 | put_user_ex(regs->cx, &sc->cx); | |
148 | put_user_ex(regs->ax, &sc->ax); | |
2601657d | 149 | #ifdef CONFIG_X86_64 |
98e3d45e HS |
150 | put_user_ex(regs->r8, &sc->r8); |
151 | put_user_ex(regs->r9, &sc->r9); | |
152 | put_user_ex(regs->r10, &sc->r10); | |
153 | put_user_ex(regs->r11, &sc->r11); | |
154 | put_user_ex(regs->r12, &sc->r12); | |
155 | put_user_ex(regs->r13, &sc->r13); | |
156 | put_user_ex(regs->r14, &sc->r14); | |
157 | put_user_ex(regs->r15, &sc->r15); | |
2601657d HS |
158 | #endif /* CONFIG_X86_64 */ |
159 | ||
51e7dc70 | 160 | put_user_ex(current->thread.trap_nr, &sc->trapno); |
98e3d45e HS |
161 | put_user_ex(current->thread.error_code, &sc->err); |
162 | put_user_ex(regs->ip, &sc->ip); | |
2601657d | 163 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
164 | put_user_ex(regs->cs, (unsigned int __user *)&sc->cs); |
165 | put_user_ex(regs->flags, &sc->flags); | |
166 | put_user_ex(regs->sp, &sc->sp_at_signal); | |
167 | put_user_ex(regs->ss, (unsigned int __user *)&sc->ss); | |
2601657d | 168 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
169 | put_user_ex(regs->flags, &sc->flags); |
170 | put_user_ex(regs->cs, &sc->cs); | |
171 | put_user_ex(0, &sc->gs); | |
172 | put_user_ex(0, &sc->fs); | |
2601657d HS |
173 | #endif /* CONFIG_X86_32 */ |
174 | ||
98e3d45e | 175 | put_user_ex(fpstate, &sc->fpstate); |
2601657d | 176 | |
98e3d45e HS |
177 | /* non-iBCS2 extensions.. */ |
178 | put_user_ex(mask, &sc->oldmask); | |
179 | put_user_ex(current->thread.cr2, &sc->cr2); | |
180 | } put_user_catch(err); | |
2601657d HS |
181 | |
182 | return err; | |
183 | } | |
184 | ||
1da177e4 | 185 | /* |
bfeb91a9 | 186 | * Set up a signal frame. |
1da177e4 | 187 | */ |
1da177e4 LT |
188 | |
189 | /* | |
190 | * Determine which stack to use.. | |
191 | */ | |
1fae0279 HS |
192 | static unsigned long align_sigframe(unsigned long sp) |
193 | { | |
194 | #ifdef CONFIG_X86_32 | |
195 | /* | |
196 | * Align the stack pointer according to the i386 ABI, | |
197 | * i.e. so that on function entry ((sp + 4) & 15) == 0. | |
198 | */ | |
199 | sp = ((sp + 4) & -16ul) - 4; | |
200 | #else /* !CONFIG_X86_32 */ | |
201 | sp = round_down(sp, 16) - 8; | |
202 | #endif | |
203 | return sp; | |
204 | } | |
205 | ||
1da177e4 | 206 | static inline void __user * |
3c1c7f10 | 207 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, |
144b0712 | 208 | void __user **fpstate) |
1da177e4 | 209 | { |
1da177e4 | 210 | /* Default to using normal stack */ |
72a671ce | 211 | unsigned long math_size = 0; |
75779f05 | 212 | unsigned long sp = regs->sp; |
72a671ce | 213 | unsigned long buf_fx = 0; |
14fc9fbc | 214 | int onsigstack = on_sig_stack(sp); |
75779f05 | 215 | |
75779f05 | 216 | /* redzone */ |
050902c0 SS |
217 | if (config_enabled(CONFIG_X86_64)) |
218 | sp -= 128; | |
1da177e4 | 219 | |
14fc9fbc HS |
220 | if (!onsigstack) { |
221 | /* This is the X/Open sanctioned signal stack switching. */ | |
222 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
0f8f3089 | 223 | if (current->sas_ss_size) |
14fc9fbc | 224 | sp = current->sas_ss_sp + current->sas_ss_size; |
050902c0 SS |
225 | } else if (config_enabled(CONFIG_X86_32) && |
226 | (regs->ss & 0xffff) != __USER_DS && | |
227 | !(ka->sa.sa_flags & SA_RESTORER) && | |
228 | ka->sa.sa_restorer) { | |
229 | /* This is the legacy signal stack switching. */ | |
14fc9fbc | 230 | sp = (unsigned long) ka->sa.sa_restorer; |
14fc9fbc | 231 | } |
1da177e4 LT |
232 | } |
233 | ||
3c1c7f10 | 234 | if (used_math()) { |
72a671ce SS |
235 | sp = alloc_mathframe(sp, config_enabled(CONFIG_X86_32), |
236 | &buf_fx, &math_size); | |
25051702 | 237 | *fpstate = (void __user *)sp; |
3c1c7f10 SS |
238 | } |
239 | ||
14fc9fbc HS |
240 | sp = align_sigframe(sp - frame_size); |
241 | ||
242 | /* | |
243 | * If we are on the alternate signal stack and would overflow it, don't. | |
244 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
245 | */ | |
246 | if (onsigstack && !likely(on_sig_stack(sp))) | |
247 | return (void __user *)-1L; | |
248 | ||
72a671ce SS |
249 | /* save i387 and extended state */ |
250 | if (used_math() && | |
251 | save_xstate_sig(*fpstate, (void __user *)buf_fx, math_size) < 0) | |
14fc9fbc HS |
252 | return (void __user *)-1L; |
253 | ||
254 | return (void __user *)sp; | |
1da177e4 LT |
255 | } |
256 | ||
75779f05 HS |
257 | #ifdef CONFIG_X86_32 |
258 | static const struct { | |
259 | u16 poplmovl; | |
260 | u32 val; | |
261 | u16 int80; | |
262 | } __attribute__((packed)) retcode = { | |
263 | 0xb858, /* popl %eax; movl $..., %eax */ | |
264 | __NR_sigreturn, | |
265 | 0x80cd, /* int $0x80 */ | |
266 | }; | |
267 | ||
268 | static const struct { | |
269 | u8 movl; | |
270 | u32 val; | |
271 | u16 int80; | |
272 | u8 pad; | |
273 | } __attribute__((packed)) rt_retcode = { | |
274 | 0xb8, /* movl $..., %eax */ | |
275 | __NR_rt_sigreturn, | |
276 | 0x80cd, /* int $0x80 */ | |
277 | 0 | |
278 | }; | |
279 | ||
7e907f48 | 280 | static int |
235b8022 | 281 | __setup_frame(int sig, struct ksignal *ksig, sigset_t *set, |
1d13024e | 282 | struct pt_regs *regs) |
1da177e4 | 283 | { |
1da177e4 | 284 | struct sigframe __user *frame; |
7e907f48 | 285 | void __user *restorer; |
1da177e4 | 286 | int err = 0; |
ab513701 | 287 | void __user *fpstate = NULL; |
1da177e4 | 288 | |
235b8022 | 289 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
290 | |
291 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 292 | return -EFAULT; |
1da177e4 | 293 | |
2ba48e16 | 294 | if (__put_user(sig, &frame->sig)) |
3d0aedd9 | 295 | return -EFAULT; |
1da177e4 | 296 | |
2ba48e16 | 297 | if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0])) |
3d0aedd9 | 298 | return -EFAULT; |
1da177e4 LT |
299 | |
300 | if (_NSIG_WORDS > 1) { | |
2ba48e16 HS |
301 | if (__copy_to_user(&frame->extramask, &set->sig[1], |
302 | sizeof(frame->extramask))) | |
3d0aedd9 | 303 | return -EFAULT; |
1da177e4 LT |
304 | } |
305 | ||
1a3e4ca4 | 306 | if (current->mm->context.vdso) |
6c3652ef | 307 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn); |
9fbbd4dd | 308 | else |
ade1af77 | 309 | restorer = &frame->retcode; |
235b8022 AV |
310 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
311 | restorer = ksig->ka.sa.sa_restorer; | |
1da177e4 LT |
312 | |
313 | /* Set up to return from userspace. */ | |
314 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 315 | |
1da177e4 | 316 | /* |
7e907f48 | 317 | * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 |
1da177e4 LT |
318 | * |
319 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
320 | * reasons and because gdb uses it as a signature to notice | |
321 | * signal handler stack frames. | |
322 | */ | |
4a612048 | 323 | err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode); |
1da177e4 LT |
324 | |
325 | if (err) | |
3d0aedd9 | 326 | return -EFAULT; |
1da177e4 LT |
327 | |
328 | /* Set up registers for signal handler */ | |
7e907f48 | 329 | regs->sp = (unsigned long)frame; |
235b8022 | 330 | regs->ip = (unsigned long)ksig->ka.sa.sa_handler; |
7e907f48 | 331 | regs->ax = (unsigned long)sig; |
92bc2056 HH |
332 | regs->dx = 0; |
333 | regs->cx = 0; | |
1da177e4 | 334 | |
65ea5b03 PA |
335 | regs->ds = __USER_DS; |
336 | regs->es = __USER_DS; | |
337 | regs->ss = __USER_DS; | |
338 | regs->cs = __USER_CS; | |
1da177e4 | 339 | |
283828f3 | 340 | return 0; |
1da177e4 LT |
341 | } |
342 | ||
235b8022 | 343 | static int __setup_rt_frame(int sig, struct ksignal *ksig, |
1d13024e | 344 | sigset_t *set, struct pt_regs *regs) |
1da177e4 | 345 | { |
1da177e4 | 346 | struct rt_sigframe __user *frame; |
7e907f48 | 347 | void __user *restorer; |
1da177e4 | 348 | int err = 0; |
ab513701 | 349 | void __user *fpstate = NULL; |
1da177e4 | 350 | |
235b8022 | 351 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
352 | |
353 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 354 | return -EFAULT; |
1da177e4 | 355 | |
98e3d45e HS |
356 | put_user_try { |
357 | put_user_ex(sig, &frame->sig); | |
358 | put_user_ex(&frame->info, &frame->pinfo); | |
359 | put_user_ex(&frame->uc, &frame->puc); | |
98e3d45e HS |
360 | |
361 | /* Create the ucontext. */ | |
362 | if (cpu_has_xsave) | |
363 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
364 | else | |
365 | put_user_ex(0, &frame->uc.uc_flags); | |
366 | put_user_ex(0, &frame->uc.uc_link); | |
a168ad26 | 367 | save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
98e3d45e HS |
368 | |
369 | /* Set up to return from userspace. */ | |
370 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn); | |
235b8022 AV |
371 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
372 | restorer = ksig->ka.sa.sa_restorer; | |
98e3d45e HS |
373 | put_user_ex(restorer, &frame->pretcode); |
374 | ||
375 | /* | |
376 | * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 | |
377 | * | |
378 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
379 | * reasons and because gdb uses it as a signature to notice | |
380 | * signal handler stack frames. | |
381 | */ | |
382 | put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode); | |
383 | } put_user_catch(err); | |
49b8c695 | 384 | |
235b8022 | 385 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); |
5e88353d PA |
386 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
387 | regs, set->sig[0]); | |
388 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
1da177e4 LT |
389 | |
390 | if (err) | |
3d0aedd9 | 391 | return -EFAULT; |
1da177e4 LT |
392 | |
393 | /* Set up registers for signal handler */ | |
7e907f48 | 394 | regs->sp = (unsigned long)frame; |
235b8022 | 395 | regs->ip = (unsigned long)ksig->ka.sa.sa_handler; |
13ad7725 | 396 | regs->ax = (unsigned long)sig; |
7e907f48 IM |
397 | regs->dx = (unsigned long)&frame->info; |
398 | regs->cx = (unsigned long)&frame->uc; | |
1da177e4 | 399 | |
65ea5b03 PA |
400 | regs->ds = __USER_DS; |
401 | regs->es = __USER_DS; | |
402 | regs->ss = __USER_DS; | |
403 | regs->cs = __USER_CS; | |
1da177e4 | 404 | |
283828f3 | 405 | return 0; |
1da177e4 | 406 | } |
bfeb91a9 | 407 | #else /* !CONFIG_X86_32 */ |
235b8022 | 408 | static int __setup_rt_frame(int sig, struct ksignal *ksig, |
bfeb91a9 HS |
409 | sigset_t *set, struct pt_regs *regs) |
410 | { | |
411 | struct rt_sigframe __user *frame; | |
412 | void __user *fp = NULL; | |
413 | int err = 0; | |
bfeb91a9 | 414 | |
235b8022 | 415 | frame = get_sigframe(&ksig->ka, regs, sizeof(struct rt_sigframe), &fp); |
bfeb91a9 HS |
416 | |
417 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
418 | return -EFAULT; | |
419 | ||
235b8022 AV |
420 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
421 | if (copy_siginfo_to_user(&frame->info, &ksig->info)) | |
bfeb91a9 HS |
422 | return -EFAULT; |
423 | } | |
424 | ||
98e3d45e HS |
425 | put_user_try { |
426 | /* Create the ucontext. */ | |
427 | if (cpu_has_xsave) | |
428 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
429 | else | |
430 | put_user_ex(0, &frame->uc.uc_flags); | |
431 | put_user_ex(0, &frame->uc.uc_link); | |
a168ad26 | 432 | save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
98e3d45e HS |
433 | |
434 | /* Set up to return from userspace. If provided, use a stub | |
435 | already in userspace. */ | |
436 | /* x86-64 should always use SA_RESTORER. */ | |
235b8022 AV |
437 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
438 | put_user_ex(ksig->ka.sa.sa_restorer, &frame->pretcode); | |
98e3d45e HS |
439 | } else { |
440 | /* could use a vstub here */ | |
441 | err |= -EFAULT; | |
442 | } | |
443 | } put_user_catch(err); | |
bfeb91a9 | 444 | |
5e88353d PA |
445 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]); |
446 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
447 | ||
bfeb91a9 HS |
448 | if (err) |
449 | return -EFAULT; | |
450 | ||
451 | /* Set up registers for signal handler */ | |
452 | regs->di = sig; | |
453 | /* In case the signal handler was declared without prototypes */ | |
454 | regs->ax = 0; | |
455 | ||
456 | /* This also works for non SA_SIGINFO handlers because they expect the | |
457 | next argument after the signal number on the stack. */ | |
458 | regs->si = (unsigned long)&frame->info; | |
459 | regs->dx = (unsigned long)&frame->uc; | |
235b8022 | 460 | regs->ip = (unsigned long) ksig->ka.sa.sa_handler; |
bfeb91a9 HS |
461 | |
462 | regs->sp = (unsigned long)frame; | |
463 | ||
464 | /* Set up the CS register to run signal handlers in 64-bit mode, | |
465 | even if the handler happens to be interrupting 32-bit code. */ | |
466 | regs->cs = __USER_CS; | |
467 | ||
468 | return 0; | |
469 | } | |
470 | #endif /* CONFIG_X86_32 */ | |
471 | ||
235b8022 AV |
472 | static int x32_setup_rt_frame(struct ksignal *ksig, |
473 | compat_sigset_t *set, | |
050902c0 SS |
474 | struct pt_regs *regs) |
475 | { | |
476 | #ifdef CONFIG_X86_X32_ABI | |
477 | struct rt_sigframe_x32 __user *frame; | |
478 | void __user *restorer; | |
479 | int err = 0; | |
480 | void __user *fpstate = NULL; | |
481 | ||
235b8022 | 482 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
050902c0 SS |
483 | |
484 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
485 | return -EFAULT; | |
486 | ||
235b8022 AV |
487 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
488 | if (copy_siginfo_to_user32(&frame->info, &ksig->info)) | |
050902c0 SS |
489 | return -EFAULT; |
490 | } | |
491 | ||
492 | put_user_try { | |
493 | /* Create the ucontext. */ | |
494 | if (cpu_has_xsave) | |
495 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
496 | else | |
497 | put_user_ex(0, &frame->uc.uc_flags); | |
498 | put_user_ex(0, &frame->uc.uc_link); | |
a168ad26 | 499 | compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
050902c0 | 500 | put_user_ex(0, &frame->uc.uc__pad0); |
050902c0 | 501 | |
235b8022 AV |
502 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
503 | restorer = ksig->ka.sa.sa_restorer; | |
050902c0 SS |
504 | } else { |
505 | /* could use a vstub here */ | |
506 | restorer = NULL; | |
507 | err |= -EFAULT; | |
508 | } | |
509 | put_user_ex(restorer, &frame->pretcode); | |
510 | } put_user_catch(err); | |
511 | ||
49b8c695 PA |
512 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
513 | regs, set->sig[0]); | |
514 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
515 | ||
050902c0 SS |
516 | if (err) |
517 | return -EFAULT; | |
518 | ||
519 | /* Set up registers for signal handler */ | |
520 | regs->sp = (unsigned long) frame; | |
235b8022 | 521 | regs->ip = (unsigned long) ksig->ka.sa.sa_handler; |
050902c0 SS |
522 | |
523 | /* We use the x32 calling convention here... */ | |
235b8022 | 524 | regs->di = ksig->sig; |
050902c0 SS |
525 | regs->si = (unsigned long) &frame->info; |
526 | regs->dx = (unsigned long) &frame->uc; | |
527 | ||
528 | loadsegment(ds, __USER_DS); | |
529 | loadsegment(es, __USER_DS); | |
530 | ||
531 | regs->cs = __USER_CS; | |
532 | regs->ss = __USER_DS; | |
533 | #endif /* CONFIG_X86_X32_ABI */ | |
534 | ||
535 | return 0; | |
536 | } | |
537 | ||
bfeb91a9 HS |
538 | /* |
539 | * Do a signal return; undo the signal stack. | |
540 | */ | |
e5fa2d06 | 541 | #ifdef CONFIG_X86_32 |
3fe26fa3 | 542 | unsigned long sys_sigreturn(void) |
bfeb91a9 | 543 | { |
3fe26fa3 | 544 | struct pt_regs *regs = current_pt_regs(); |
bfeb91a9 | 545 | struct sigframe __user *frame; |
bfeb91a9 HS |
546 | unsigned long ax; |
547 | sigset_t set; | |
548 | ||
bfeb91a9 HS |
549 | frame = (struct sigframe __user *)(regs->sp - 8); |
550 | ||
551 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
552 | goto badframe; | |
553 | if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1 | |
554 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
555 | sizeof(frame->extramask)))) | |
556 | goto badframe; | |
557 | ||
3982294b | 558 | set_current_blocked(&set); |
bfeb91a9 HS |
559 | |
560 | if (restore_sigcontext(regs, &frame->sc, &ax)) | |
561 | goto badframe; | |
562 | return ax; | |
563 | ||
564 | badframe: | |
ae417bb4 | 565 | signal_fault(regs, frame, "sigreturn"); |
bfeb91a9 HS |
566 | |
567 | return 0; | |
568 | } | |
e5fa2d06 | 569 | #endif /* CONFIG_X86_32 */ |
bfeb91a9 | 570 | |
3fe26fa3 | 571 | long sys_rt_sigreturn(void) |
bfeb91a9 | 572 | { |
3fe26fa3 | 573 | struct pt_regs *regs = current_pt_regs(); |
bfeb91a9 HS |
574 | struct rt_sigframe __user *frame; |
575 | unsigned long ax; | |
576 | sigset_t set; | |
577 | ||
578 | frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); | |
579 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
580 | goto badframe; | |
581 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
582 | goto badframe; | |
583 | ||
e9bd3f0f | 584 | set_current_blocked(&set); |
bfeb91a9 HS |
585 | |
586 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) | |
587 | goto badframe; | |
588 | ||
c40702c4 | 589 | if (restore_altstack(&frame->uc.uc_stack)) |
bfeb91a9 HS |
590 | goto badframe; |
591 | ||
592 | return ax; | |
593 | ||
594 | badframe: | |
595 | signal_fault(regs, frame, "rt_sigreturn"); | |
596 | return 0; | |
597 | } | |
598 | ||
1da177e4 | 599 | /* |
7e907f48 IM |
600 | * OK, we're invoking a handler: |
601 | */ | |
8d8c13bd HS |
602 | static int signr_convert(int sig) |
603 | { | |
96bf84b7 | 604 | #ifdef CONFIG_X86_32 |
8d8c13bd HS |
605 | struct thread_info *info = current_thread_info(); |
606 | ||
607 | if (info->exec_domain && info->exec_domain->signal_invmap && sig < 32) | |
608 | return info->exec_domain->signal_invmap[sig]; | |
96bf84b7 | 609 | #endif /* CONFIG_X86_32 */ |
8d8c13bd HS |
610 | return sig; |
611 | } | |
612 | ||
1d13024e | 613 | static int |
235b8022 | 614 | setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) |
1d13024e | 615 | { |
235b8022 | 616 | int usig = signr_convert(ksig->sig); |
b7f9a11a | 617 | sigset_t *set = sigmask_to_save(); |
050902c0 | 618 | compat_sigset_t *cset = (compat_sigset_t *) set; |
1d13024e HS |
619 | |
620 | /* Set up the stack frame */ | |
050902c0 | 621 | if (is_ia32_frame()) { |
235b8022 AV |
622 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
623 | return ia32_setup_rt_frame(usig, ksig, cset, regs); | |
455edbc4 | 624 | else |
235b8022 | 625 | return ia32_setup_frame(usig, ksig, cset, regs); |
050902c0 | 626 | } else if (is_x32_frame()) { |
235b8022 | 627 | return x32_setup_rt_frame(ksig, cset, regs); |
c5a37394 | 628 | } else { |
235b8022 | 629 | return __setup_rt_frame(ksig->sig, ksig, set, regs); |
c5a37394 | 630 | } |
1d13024e HS |
631 | } |
632 | ||
a610d6e6 | 633 | static void |
235b8022 | 634 | handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
1da177e4 | 635 | { |
235b8022 | 636 | bool failed; |
1da177e4 | 637 | /* Are we from a system call? */ |
bb57925f | 638 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 639 | /* If so, check system call restarting.. */ |
bb57925f | 640 | switch (syscall_get_error(current, regs)) { |
ac66f3fd HH |
641 | case -ERESTART_RESTARTBLOCK: |
642 | case -ERESTARTNOHAND: | |
643 | regs->ax = -EINTR; | |
644 | break; | |
645 | ||
646 | case -ERESTARTSYS: | |
235b8022 | 647 | if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
65ea5b03 | 648 | regs->ax = -EINTR; |
1da177e4 | 649 | break; |
ac66f3fd HH |
650 | } |
651 | /* fallthrough */ | |
652 | case -ERESTARTNOINTR: | |
653 | regs->ax = regs->orig_ax; | |
654 | regs->ip -= 2; | |
655 | break; | |
1da177e4 LT |
656 | } |
657 | } | |
658 | ||
659 | /* | |
e1f28773 RM |
660 | * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF |
661 | * flag so that register information in the sigcontext is correct. | |
1da177e4 | 662 | */ |
65ea5b03 | 663 | if (unlikely(regs->flags & X86_EFLAGS_TF) && |
e1f28773 | 664 | likely(test_and_clear_thread_flag(TIF_FORCED_TF))) |
65ea5b03 | 665 | regs->flags &= ~X86_EFLAGS_TF; |
1da177e4 | 666 | |
235b8022 AV |
667 | failed = (setup_rt_frame(ksig, regs) < 0); |
668 | if (!failed) { | |
669 | /* | |
670 | * Clear the direction flag as per the ABI for function entry. | |
671 | */ | |
672 | regs->flags &= ~X86_EFLAGS_DF; | |
673 | /* | |
674 | * Clear TF when entering the signal handler, but | |
675 | * notify any tracer that was single-stepping it. | |
676 | * The tracer may want to single-step inside the | |
677 | * handler too. | |
678 | */ | |
679 | regs->flags &= ~X86_EFLAGS_TF; | |
fb5b6e7e ON |
680 | /* |
681 | * Ensure the signal handler starts with the new fpu state. | |
682 | */ | |
683 | if (used_math()) | |
684 | drop_init_fpu(current); | |
a610d6e6 | 685 | } |
235b8022 | 686 | signal_setup_done(failed, ksig, test_thread_flag(TIF_SINGLESTEP)); |
1da177e4 LT |
687 | } |
688 | ||
f7948990 DL |
689 | static inline unsigned long get_nr_restart_syscall(const struct pt_regs *regs) |
690 | { | |
691 | #if defined(CONFIG_X86_32) || !defined(CONFIG_X86_64) | |
692 | return __NR_restart_syscall; | |
693 | #else /* !CONFIG_X86_32 && CONFIG_X86_64 */ | |
694 | return test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : | |
695 | __NR_restart_syscall | (regs->orig_ax & __X32_SYSCALL_BIT); | |
696 | #endif /* CONFIG_X86_32 || !CONFIG_X86_64 */ | |
697 | } | |
57917752 | 698 | |
1da177e4 LT |
699 | /* |
700 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
701 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
702 | * mistake. | |
703 | */ | |
75604d7f | 704 | static void do_signal(struct pt_regs *regs) |
1da177e4 | 705 | { |
235b8022 | 706 | struct ksignal ksig; |
1da177e4 | 707 | |
235b8022 | 708 | if (get_signal(&ksig)) { |
7e907f48 | 709 | /* Whee! Actually deliver the signal. */ |
235b8022 | 710 | handle_signal(&ksig, regs); |
283828f3 | 711 | return; |
1da177e4 LT |
712 | } |
713 | ||
1da177e4 | 714 | /* Did we come from a system call? */ |
bb57925f | 715 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 716 | /* Restart the system call - no handlers present */ |
bb57925f | 717 | switch (syscall_get_error(current, regs)) { |
283828f3 DH |
718 | case -ERESTARTNOHAND: |
719 | case -ERESTARTSYS: | |
720 | case -ERESTARTNOINTR: | |
65ea5b03 PA |
721 | regs->ax = regs->orig_ax; |
722 | regs->ip -= 2; | |
283828f3 DH |
723 | break; |
724 | ||
725 | case -ERESTART_RESTARTBLOCK: | |
f7948990 | 726 | regs->ax = get_nr_restart_syscall(regs); |
65ea5b03 | 727 | regs->ip -= 2; |
283828f3 | 728 | break; |
1da177e4 LT |
729 | } |
730 | } | |
283828f3 | 731 | |
ac66f3fd HH |
732 | /* |
733 | * If there's no signal to deliver, we just put the saved sigmask | |
734 | * back. | |
735 | */ | |
51a7b448 | 736 | restore_saved_sigmask(); |
1da177e4 LT |
737 | } |
738 | ||
739 | /* | |
740 | * notification of userspace execution resumption | |
283828f3 | 741 | * - triggered by the TIF_WORK_MASK flags |
1da177e4 | 742 | */ |
7e907f48 IM |
743 | void |
744 | do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) | |
1da177e4 | 745 | { |
91d1aa43 | 746 | user_exit(); |
edf55fda | 747 | |
c1ebf835 | 748 | #ifdef CONFIG_X86_MCE |
ee847c54 HS |
749 | /* notify userspace of pending MCEs */ |
750 | if (thread_info_flags & _TIF_MCE_NOTIFY) | |
9b1beaf2 | 751 | mce_notify_process(); |
ee847c54 HS |
752 | #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ |
753 | ||
db023ea5 | 754 | if (thread_info_flags & _TIF_UPROBE) |
0326f5a9 | 755 | uprobe_notify_resume(regs); |
0326f5a9 | 756 | |
1da177e4 | 757 | /* deal with pending signal delivery */ |
5a8da0ea | 758 | if (thread_info_flags & _TIF_SIGPENDING) |
283828f3 | 759 | do_signal(regs); |
8f4d37ec | 760 | |
59e52130 RM |
761 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { |
762 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
763 | tracehook_notify_resume(regs); | |
764 | } | |
7c68af6e AK |
765 | if (thread_info_flags & _TIF_USER_RETURN_NOTIFY) |
766 | fire_user_return_notifiers(); | |
59e52130 | 767 | |
91d1aa43 | 768 | user_enter(); |
1da177e4 | 769 | } |
72fa50f4 HS |
770 | |
771 | void signal_fault(struct pt_regs *regs, void __user *frame, char *where) | |
772 | { | |
773 | struct task_struct *me = current; | |
774 | ||
775 | if (show_unhandled_signals && printk_ratelimit()) { | |
ae417bb4 | 776 | printk("%s" |
72fa50f4 | 777 | "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx", |
ae417bb4 | 778 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
72fa50f4 HS |
779 | me->comm, me->pid, where, frame, |
780 | regs->ip, regs->sp, regs->orig_ax); | |
781 | print_vma_addr(" in ", regs->ip); | |
c767a54b | 782 | pr_cont("\n"); |
72fa50f4 HS |
783 | } |
784 | ||
785 | force_sig(SIGSEGV, me); | |
786 | } | |
c5a37394 PA |
787 | |
788 | #ifdef CONFIG_X86_X32_ABI | |
3fe26fa3 | 789 | asmlinkage long sys32_x32_rt_sigreturn(void) |
c5a37394 | 790 | { |
3fe26fa3 | 791 | struct pt_regs *regs = current_pt_regs(); |
c5a37394 PA |
792 | struct rt_sigframe_x32 __user *frame; |
793 | sigset_t set; | |
794 | unsigned long ax; | |
c5a37394 PA |
795 | |
796 | frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8); | |
797 | ||
798 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
799 | goto badframe; | |
800 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
801 | goto badframe; | |
802 | ||
c5a37394 PA |
803 | set_current_blocked(&set); |
804 | ||
805 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) | |
806 | goto badframe; | |
807 | ||
90268439 | 808 | if (compat_restore_altstack(&frame->uc.uc_stack)) |
c5a37394 PA |
809 | goto badframe; |
810 | ||
811 | return ax; | |
812 | ||
813 | badframe: | |
814 | signal_fault(regs, frame, "x32 rt_sigreturn"); | |
815 | return 0; | |
816 | } | |
817 | #endif |