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 | |
d9a89a26 TH |
46 | #define COPY(x) do { \ |
47 | get_user_ex(regs->x, &sc->x); \ | |
48 | } while (0) | |
2601657d | 49 | |
d9a89a26 TH |
50 | #define GET_SEG(seg) ({ \ |
51 | unsigned short tmp; \ | |
52 | get_user_ex(tmp, &sc->seg); \ | |
53 | tmp; \ | |
54 | }) | |
2601657d | 55 | |
d9a89a26 TH |
56 | #define COPY_SEG(seg) do { \ |
57 | regs->seg = GET_SEG(seg); \ | |
58 | } while (0) | |
2601657d | 59 | |
d9a89a26 TH |
60 | #define COPY_SEG_CPL3(seg) do { \ |
61 | regs->seg = GET_SEG(seg) | 3; \ | |
62 | } while (0) | |
2601657d | 63 | |
85139422 PA |
64 | int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, |
65 | unsigned long *pax) | |
2601657d HS |
66 | { |
67 | void __user *buf; | |
68 | unsigned int tmpflags; | |
69 | unsigned int err = 0; | |
70 | ||
71 | /* Always make any pending restarted system calls return -EINTR */ | |
72 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
73 | ||
98e3d45e HS |
74 | get_user_try { |
75 | ||
2601657d | 76 | #ifdef CONFIG_X86_32 |
d9a89a26 | 77 | set_user_gs(regs, GET_SEG(gs)); |
98e3d45e HS |
78 | COPY_SEG(fs); |
79 | COPY_SEG(es); | |
80 | COPY_SEG(ds); | |
2601657d HS |
81 | #endif /* CONFIG_X86_32 */ |
82 | ||
98e3d45e HS |
83 | COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); |
84 | COPY(dx); COPY(cx); COPY(ip); | |
2601657d HS |
85 | |
86 | #ifdef CONFIG_X86_64 | |
98e3d45e HS |
87 | COPY(r8); |
88 | COPY(r9); | |
89 | COPY(r10); | |
90 | COPY(r11); | |
91 | COPY(r12); | |
92 | COPY(r13); | |
93 | COPY(r14); | |
94 | COPY(r15); | |
2601657d HS |
95 | #endif /* CONFIG_X86_64 */ |
96 | ||
97 | #ifdef CONFIG_X86_32 | |
98e3d45e HS |
98 | COPY_SEG_CPL3(cs); |
99 | COPY_SEG_CPL3(ss); | |
2601657d | 100 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
101 | /* Kernel saves and restores only the CS segment register on signals, |
102 | * which is the bare minimum needed to allow mixed 32/64-bit code. | |
103 | * App's signal handler can save/restore other segments if needed. */ | |
104 | COPY_SEG_CPL3(cs); | |
2601657d HS |
105 | #endif /* CONFIG_X86_32 */ |
106 | ||
98e3d45e HS |
107 | get_user_ex(tmpflags, &sc->flags); |
108 | regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
109 | regs->orig_ax = -1; /* disable syscall checks */ | |
110 | ||
111 | get_user_ex(buf, &sc->fpstate); | |
2601657d | 112 | |
98e3d45e HS |
113 | get_user_ex(*pax, &sc->ax); |
114 | } get_user_catch(err); | |
2601657d | 115 | |
49b8c695 | 116 | err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32)); |
5e88353d | 117 | |
2601657d HS |
118 | return err; |
119 | } | |
120 | ||
85139422 PA |
121 | int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, |
122 | struct pt_regs *regs, unsigned long mask) | |
2601657d HS |
123 | { |
124 | int err = 0; | |
125 | ||
98e3d45e | 126 | put_user_try { |
2601657d | 127 | |
98e3d45e | 128 | #ifdef CONFIG_X86_32 |
d9a89a26 | 129 | put_user_ex(get_user_gs(regs), (unsigned int __user *)&sc->gs); |
98e3d45e HS |
130 | put_user_ex(regs->fs, (unsigned int __user *)&sc->fs); |
131 | put_user_ex(regs->es, (unsigned int __user *)&sc->es); | |
132 | put_user_ex(regs->ds, (unsigned int __user *)&sc->ds); | |
2601657d HS |
133 | #endif /* CONFIG_X86_32 */ |
134 | ||
98e3d45e HS |
135 | put_user_ex(regs->di, &sc->di); |
136 | put_user_ex(regs->si, &sc->si); | |
137 | put_user_ex(regs->bp, &sc->bp); | |
138 | put_user_ex(regs->sp, &sc->sp); | |
139 | put_user_ex(regs->bx, &sc->bx); | |
140 | put_user_ex(regs->dx, &sc->dx); | |
141 | put_user_ex(regs->cx, &sc->cx); | |
142 | put_user_ex(regs->ax, &sc->ax); | |
2601657d | 143 | #ifdef CONFIG_X86_64 |
98e3d45e HS |
144 | put_user_ex(regs->r8, &sc->r8); |
145 | put_user_ex(regs->r9, &sc->r9); | |
146 | put_user_ex(regs->r10, &sc->r10); | |
147 | put_user_ex(regs->r11, &sc->r11); | |
148 | put_user_ex(regs->r12, &sc->r12); | |
149 | put_user_ex(regs->r13, &sc->r13); | |
150 | put_user_ex(regs->r14, &sc->r14); | |
151 | put_user_ex(regs->r15, &sc->r15); | |
2601657d HS |
152 | #endif /* CONFIG_X86_64 */ |
153 | ||
51e7dc70 | 154 | put_user_ex(current->thread.trap_nr, &sc->trapno); |
98e3d45e HS |
155 | put_user_ex(current->thread.error_code, &sc->err); |
156 | put_user_ex(regs->ip, &sc->ip); | |
2601657d | 157 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
158 | put_user_ex(regs->cs, (unsigned int __user *)&sc->cs); |
159 | put_user_ex(regs->flags, &sc->flags); | |
160 | put_user_ex(regs->sp, &sc->sp_at_signal); | |
161 | put_user_ex(regs->ss, (unsigned int __user *)&sc->ss); | |
2601657d | 162 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
163 | put_user_ex(regs->flags, &sc->flags); |
164 | put_user_ex(regs->cs, &sc->cs); | |
165 | put_user_ex(0, &sc->gs); | |
166 | put_user_ex(0, &sc->fs); | |
2601657d HS |
167 | #endif /* CONFIG_X86_32 */ |
168 | ||
98e3d45e | 169 | put_user_ex(fpstate, &sc->fpstate); |
2601657d | 170 | |
98e3d45e HS |
171 | /* non-iBCS2 extensions.. */ |
172 | put_user_ex(mask, &sc->oldmask); | |
173 | put_user_ex(current->thread.cr2, &sc->cr2); | |
174 | } put_user_catch(err); | |
2601657d HS |
175 | |
176 | return err; | |
177 | } | |
178 | ||
1da177e4 | 179 | /* |
bfeb91a9 | 180 | * Set up a signal frame. |
1da177e4 | 181 | */ |
1da177e4 LT |
182 | |
183 | /* | |
184 | * Determine which stack to use.. | |
185 | */ | |
1fae0279 HS |
186 | static unsigned long align_sigframe(unsigned long sp) |
187 | { | |
188 | #ifdef CONFIG_X86_32 | |
189 | /* | |
190 | * Align the stack pointer according to the i386 ABI, | |
191 | * i.e. so that on function entry ((sp + 4) & 15) == 0. | |
192 | */ | |
193 | sp = ((sp + 4) & -16ul) - 4; | |
194 | #else /* !CONFIG_X86_32 */ | |
195 | sp = round_down(sp, 16) - 8; | |
196 | #endif | |
197 | return sp; | |
198 | } | |
199 | ||
1da177e4 | 200 | static inline void __user * |
3c1c7f10 | 201 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, |
144b0712 | 202 | void __user **fpstate) |
1da177e4 | 203 | { |
1da177e4 | 204 | /* Default to using normal stack */ |
72a671ce | 205 | unsigned long math_size = 0; |
75779f05 | 206 | unsigned long sp = regs->sp; |
72a671ce | 207 | unsigned long buf_fx = 0; |
14fc9fbc | 208 | int onsigstack = on_sig_stack(sp); |
75779f05 | 209 | |
75779f05 | 210 | /* redzone */ |
050902c0 SS |
211 | if (config_enabled(CONFIG_X86_64)) |
212 | sp -= 128; | |
1da177e4 | 213 | |
14fc9fbc HS |
214 | if (!onsigstack) { |
215 | /* This is the X/Open sanctioned signal stack switching. */ | |
216 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
0f8f3089 | 217 | if (current->sas_ss_size) |
14fc9fbc | 218 | sp = current->sas_ss_sp + current->sas_ss_size; |
050902c0 SS |
219 | } else if (config_enabled(CONFIG_X86_32) && |
220 | (regs->ss & 0xffff) != __USER_DS && | |
221 | !(ka->sa.sa_flags & SA_RESTORER) && | |
222 | ka->sa.sa_restorer) { | |
223 | /* This is the legacy signal stack switching. */ | |
14fc9fbc | 224 | sp = (unsigned long) ka->sa.sa_restorer; |
14fc9fbc | 225 | } |
1da177e4 LT |
226 | } |
227 | ||
3c1c7f10 | 228 | if (used_math()) { |
72a671ce SS |
229 | sp = alloc_mathframe(sp, config_enabled(CONFIG_X86_32), |
230 | &buf_fx, &math_size); | |
25051702 | 231 | *fpstate = (void __user *)sp; |
3c1c7f10 SS |
232 | } |
233 | ||
14fc9fbc HS |
234 | sp = align_sigframe(sp - frame_size); |
235 | ||
236 | /* | |
237 | * If we are on the alternate signal stack and would overflow it, don't. | |
238 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
239 | */ | |
240 | if (onsigstack && !likely(on_sig_stack(sp))) | |
241 | return (void __user *)-1L; | |
242 | ||
72a671ce SS |
243 | /* save i387 and extended state */ |
244 | if (used_math() && | |
245 | save_xstate_sig(*fpstate, (void __user *)buf_fx, math_size) < 0) | |
14fc9fbc HS |
246 | return (void __user *)-1L; |
247 | ||
248 | return (void __user *)sp; | |
1da177e4 LT |
249 | } |
250 | ||
75779f05 HS |
251 | #ifdef CONFIG_X86_32 |
252 | static const struct { | |
253 | u16 poplmovl; | |
254 | u32 val; | |
255 | u16 int80; | |
256 | } __attribute__((packed)) retcode = { | |
257 | 0xb858, /* popl %eax; movl $..., %eax */ | |
258 | __NR_sigreturn, | |
259 | 0x80cd, /* int $0x80 */ | |
260 | }; | |
261 | ||
262 | static const struct { | |
263 | u8 movl; | |
264 | u32 val; | |
265 | u16 int80; | |
266 | u8 pad; | |
267 | } __attribute__((packed)) rt_retcode = { | |
268 | 0xb8, /* movl $..., %eax */ | |
269 | __NR_rt_sigreturn, | |
270 | 0x80cd, /* int $0x80 */ | |
271 | 0 | |
272 | }; | |
273 | ||
7e907f48 | 274 | static int |
235b8022 | 275 | __setup_frame(int sig, struct ksignal *ksig, sigset_t *set, |
1d13024e | 276 | struct pt_regs *regs) |
1da177e4 | 277 | { |
1da177e4 | 278 | struct sigframe __user *frame; |
7e907f48 | 279 | void __user *restorer; |
1da177e4 | 280 | int err = 0; |
ab513701 | 281 | void __user *fpstate = NULL; |
1da177e4 | 282 | |
235b8022 | 283 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
284 | |
285 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 286 | return -EFAULT; |
1da177e4 | 287 | |
2ba48e16 | 288 | if (__put_user(sig, &frame->sig)) |
3d0aedd9 | 289 | return -EFAULT; |
1da177e4 | 290 | |
2ba48e16 | 291 | if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0])) |
3d0aedd9 | 292 | return -EFAULT; |
1da177e4 LT |
293 | |
294 | if (_NSIG_WORDS > 1) { | |
2ba48e16 HS |
295 | if (__copy_to_user(&frame->extramask, &set->sig[1], |
296 | sizeof(frame->extramask))) | |
3d0aedd9 | 297 | return -EFAULT; |
1da177e4 LT |
298 | } |
299 | ||
1a3e4ca4 | 300 | if (current->mm->context.vdso) |
6c3652ef | 301 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn); |
9fbbd4dd | 302 | else |
ade1af77 | 303 | restorer = &frame->retcode; |
235b8022 AV |
304 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
305 | restorer = ksig->ka.sa.sa_restorer; | |
1da177e4 LT |
306 | |
307 | /* Set up to return from userspace. */ | |
308 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 309 | |
1da177e4 | 310 | /* |
7e907f48 | 311 | * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 |
1da177e4 LT |
312 | * |
313 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
314 | * reasons and because gdb uses it as a signature to notice | |
315 | * signal handler stack frames. | |
316 | */ | |
4a612048 | 317 | err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode); |
1da177e4 LT |
318 | |
319 | if (err) | |
3d0aedd9 | 320 | return -EFAULT; |
1da177e4 LT |
321 | |
322 | /* Set up registers for signal handler */ | |
7e907f48 | 323 | regs->sp = (unsigned long)frame; |
235b8022 | 324 | regs->ip = (unsigned long)ksig->ka.sa.sa_handler; |
7e907f48 | 325 | regs->ax = (unsigned long)sig; |
92bc2056 HH |
326 | regs->dx = 0; |
327 | regs->cx = 0; | |
1da177e4 | 328 | |
65ea5b03 PA |
329 | regs->ds = __USER_DS; |
330 | regs->es = __USER_DS; | |
331 | regs->ss = __USER_DS; | |
332 | regs->cs = __USER_CS; | |
1da177e4 | 333 | |
283828f3 | 334 | return 0; |
1da177e4 LT |
335 | } |
336 | ||
235b8022 | 337 | static int __setup_rt_frame(int sig, struct ksignal *ksig, |
1d13024e | 338 | sigset_t *set, struct pt_regs *regs) |
1da177e4 | 339 | { |
1da177e4 | 340 | struct rt_sigframe __user *frame; |
7e907f48 | 341 | void __user *restorer; |
1da177e4 | 342 | int err = 0; |
ab513701 | 343 | void __user *fpstate = NULL; |
1da177e4 | 344 | |
235b8022 | 345 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
346 | |
347 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 348 | return -EFAULT; |
1da177e4 | 349 | |
98e3d45e HS |
350 | put_user_try { |
351 | put_user_ex(sig, &frame->sig); | |
352 | put_user_ex(&frame->info, &frame->pinfo); | |
353 | put_user_ex(&frame->uc, &frame->puc); | |
98e3d45e HS |
354 | |
355 | /* Create the ucontext. */ | |
356 | if (cpu_has_xsave) | |
357 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
358 | else | |
359 | put_user_ex(0, &frame->uc.uc_flags); | |
360 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 361 | save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
98e3d45e HS |
362 | |
363 | /* Set up to return from userspace. */ | |
364 | restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn); | |
235b8022 AV |
365 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
366 | restorer = ksig->ka.sa.sa_restorer; | |
98e3d45e HS |
367 | put_user_ex(restorer, &frame->pretcode); |
368 | ||
369 | /* | |
370 | * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 | |
371 | * | |
372 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
373 | * reasons and because gdb uses it as a signature to notice | |
374 | * signal handler stack frames. | |
375 | */ | |
376 | put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode); | |
377 | } put_user_catch(err); | |
49b8c695 | 378 | |
235b8022 | 379 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); |
5e88353d PA |
380 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
381 | regs, set->sig[0]); | |
382 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
1da177e4 LT |
383 | |
384 | if (err) | |
3d0aedd9 | 385 | return -EFAULT; |
1da177e4 LT |
386 | |
387 | /* Set up registers for signal handler */ | |
7e907f48 | 388 | regs->sp = (unsigned long)frame; |
235b8022 | 389 | regs->ip = (unsigned long)ksig->ka.sa.sa_handler; |
13ad7725 | 390 | regs->ax = (unsigned long)sig; |
7e907f48 IM |
391 | regs->dx = (unsigned long)&frame->info; |
392 | regs->cx = (unsigned long)&frame->uc; | |
1da177e4 | 393 | |
65ea5b03 PA |
394 | regs->ds = __USER_DS; |
395 | regs->es = __USER_DS; | |
396 | regs->ss = __USER_DS; | |
397 | regs->cs = __USER_CS; | |
1da177e4 | 398 | |
283828f3 | 399 | return 0; |
1da177e4 | 400 | } |
bfeb91a9 | 401 | #else /* !CONFIG_X86_32 */ |
235b8022 | 402 | static int __setup_rt_frame(int sig, struct ksignal *ksig, |
bfeb91a9 HS |
403 | sigset_t *set, struct pt_regs *regs) |
404 | { | |
405 | struct rt_sigframe __user *frame; | |
406 | void __user *fp = NULL; | |
407 | int err = 0; | |
bfeb91a9 | 408 | |
235b8022 | 409 | frame = get_sigframe(&ksig->ka, regs, sizeof(struct rt_sigframe), &fp); |
bfeb91a9 HS |
410 | |
411 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
412 | return -EFAULT; | |
413 | ||
235b8022 AV |
414 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
415 | if (copy_siginfo_to_user(&frame->info, &ksig->info)) | |
bfeb91a9 HS |
416 | return -EFAULT; |
417 | } | |
418 | ||
98e3d45e HS |
419 | put_user_try { |
420 | /* Create the ucontext. */ | |
421 | if (cpu_has_xsave) | |
422 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
423 | else | |
424 | put_user_ex(0, &frame->uc.uc_flags); | |
425 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 426 | save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
98e3d45e HS |
427 | |
428 | /* Set up to return from userspace. If provided, use a stub | |
429 | already in userspace. */ | |
430 | /* x86-64 should always use SA_RESTORER. */ | |
235b8022 AV |
431 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
432 | put_user_ex(ksig->ka.sa.sa_restorer, &frame->pretcode); | |
98e3d45e HS |
433 | } else { |
434 | /* could use a vstub here */ | |
435 | err |= -EFAULT; | |
436 | } | |
437 | } put_user_catch(err); | |
bfeb91a9 | 438 | |
5e88353d PA |
439 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]); |
440 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
441 | ||
bfeb91a9 HS |
442 | if (err) |
443 | return -EFAULT; | |
444 | ||
445 | /* Set up registers for signal handler */ | |
446 | regs->di = sig; | |
447 | /* In case the signal handler was declared without prototypes */ | |
448 | regs->ax = 0; | |
449 | ||
450 | /* This also works for non SA_SIGINFO handlers because they expect the | |
451 | next argument after the signal number on the stack. */ | |
452 | regs->si = (unsigned long)&frame->info; | |
453 | regs->dx = (unsigned long)&frame->uc; | |
235b8022 | 454 | regs->ip = (unsigned long) ksig->ka.sa.sa_handler; |
bfeb91a9 HS |
455 | |
456 | regs->sp = (unsigned long)frame; | |
457 | ||
458 | /* Set up the CS register to run signal handlers in 64-bit mode, | |
459 | even if the handler happens to be interrupting 32-bit code. */ | |
460 | regs->cs = __USER_CS; | |
461 | ||
462 | return 0; | |
463 | } | |
464 | #endif /* CONFIG_X86_32 */ | |
465 | ||
235b8022 AV |
466 | static int x32_setup_rt_frame(struct ksignal *ksig, |
467 | compat_sigset_t *set, | |
050902c0 SS |
468 | struct pt_regs *regs) |
469 | { | |
470 | #ifdef CONFIG_X86_X32_ABI | |
471 | struct rt_sigframe_x32 __user *frame; | |
472 | void __user *restorer; | |
473 | int err = 0; | |
474 | void __user *fpstate = NULL; | |
475 | ||
235b8022 | 476 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
050902c0 SS |
477 | |
478 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
479 | return -EFAULT; | |
480 | ||
235b8022 AV |
481 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
482 | if (copy_siginfo_to_user32(&frame->info, &ksig->info)) | |
050902c0 SS |
483 | return -EFAULT; |
484 | } | |
485 | ||
486 | put_user_try { | |
487 | /* Create the ucontext. */ | |
488 | if (cpu_has_xsave) | |
489 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
490 | else | |
491 | put_user_ex(0, &frame->uc.uc_flags); | |
492 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 493 | compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
050902c0 | 494 | put_user_ex(0, &frame->uc.uc__pad0); |
050902c0 | 495 | |
235b8022 AV |
496 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
497 | restorer = ksig->ka.sa.sa_restorer; | |
050902c0 SS |
498 | } else { |
499 | /* could use a vstub here */ | |
500 | restorer = NULL; | |
501 | err |= -EFAULT; | |
502 | } | |
503 | put_user_ex(restorer, &frame->pretcode); | |
504 | } put_user_catch(err); | |
505 | ||
49b8c695 PA |
506 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
507 | regs, set->sig[0]); | |
508 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
509 | ||
050902c0 SS |
510 | if (err) |
511 | return -EFAULT; | |
512 | ||
513 | /* Set up registers for signal handler */ | |
514 | regs->sp = (unsigned long) frame; | |
235b8022 | 515 | regs->ip = (unsigned long) ksig->ka.sa.sa_handler; |
050902c0 SS |
516 | |
517 | /* We use the x32 calling convention here... */ | |
235b8022 | 518 | regs->di = ksig->sig; |
050902c0 SS |
519 | regs->si = (unsigned long) &frame->info; |
520 | regs->dx = (unsigned long) &frame->uc; | |
521 | ||
522 | loadsegment(ds, __USER_DS); | |
523 | loadsegment(es, __USER_DS); | |
524 | ||
525 | regs->cs = __USER_CS; | |
526 | regs->ss = __USER_DS; | |
527 | #endif /* CONFIG_X86_X32_ABI */ | |
528 | ||
529 | return 0; | |
530 | } | |
531 | ||
bfeb91a9 HS |
532 | /* |
533 | * Do a signal return; undo the signal stack. | |
534 | */ | |
e5fa2d06 | 535 | #ifdef CONFIG_X86_32 |
ff49103f | 536 | asmlinkage unsigned long sys_sigreturn(void) |
bfeb91a9 | 537 | { |
3fe26fa3 | 538 | struct pt_regs *regs = current_pt_regs(); |
bfeb91a9 | 539 | struct sigframe __user *frame; |
bfeb91a9 HS |
540 | unsigned long ax; |
541 | sigset_t set; | |
542 | ||
bfeb91a9 HS |
543 | frame = (struct sigframe __user *)(regs->sp - 8); |
544 | ||
545 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
546 | goto badframe; | |
547 | if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1 | |
548 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
549 | sizeof(frame->extramask)))) | |
550 | goto badframe; | |
551 | ||
3982294b | 552 | set_current_blocked(&set); |
bfeb91a9 HS |
553 | |
554 | if (restore_sigcontext(regs, &frame->sc, &ax)) | |
555 | goto badframe; | |
556 | return ax; | |
557 | ||
558 | badframe: | |
ae417bb4 | 559 | signal_fault(regs, frame, "sigreturn"); |
bfeb91a9 HS |
560 | |
561 | return 0; | |
562 | } | |
e5fa2d06 | 563 | #endif /* CONFIG_X86_32 */ |
bfeb91a9 | 564 | |
ff49103f | 565 | asmlinkage long sys_rt_sigreturn(void) |
bfeb91a9 | 566 | { |
3fe26fa3 | 567 | struct pt_regs *regs = current_pt_regs(); |
bfeb91a9 HS |
568 | struct rt_sigframe __user *frame; |
569 | unsigned long ax; | |
570 | sigset_t set; | |
571 | ||
572 | frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); | |
573 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
574 | goto badframe; | |
575 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
576 | goto badframe; | |
577 | ||
e9bd3f0f | 578 | set_current_blocked(&set); |
bfeb91a9 HS |
579 | |
580 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) | |
581 | goto badframe; | |
582 | ||
c40702c4 | 583 | if (restore_altstack(&frame->uc.uc_stack)) |
bfeb91a9 HS |
584 | goto badframe; |
585 | ||
586 | return ax; | |
587 | ||
588 | badframe: | |
589 | signal_fault(regs, frame, "rt_sigreturn"); | |
590 | return 0; | |
591 | } | |
592 | ||
1da177e4 | 593 | /* |
7e907f48 IM |
594 | * OK, we're invoking a handler: |
595 | */ | |
8d8c13bd HS |
596 | static int signr_convert(int sig) |
597 | { | |
96bf84b7 | 598 | #ifdef CONFIG_X86_32 |
8d8c13bd HS |
599 | struct thread_info *info = current_thread_info(); |
600 | ||
601 | if (info->exec_domain && info->exec_domain->signal_invmap && sig < 32) | |
602 | return info->exec_domain->signal_invmap[sig]; | |
96bf84b7 | 603 | #endif /* CONFIG_X86_32 */ |
8d8c13bd HS |
604 | return sig; |
605 | } | |
606 | ||
1d13024e | 607 | static int |
235b8022 | 608 | setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) |
1d13024e | 609 | { |
235b8022 | 610 | int usig = signr_convert(ksig->sig); |
b7f9a11a | 611 | sigset_t *set = sigmask_to_save(); |
050902c0 | 612 | compat_sigset_t *cset = (compat_sigset_t *) set; |
1d13024e HS |
613 | |
614 | /* Set up the stack frame */ | |
050902c0 | 615 | if (is_ia32_frame()) { |
235b8022 AV |
616 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
617 | return ia32_setup_rt_frame(usig, ksig, cset, regs); | |
455edbc4 | 618 | else |
235b8022 | 619 | return ia32_setup_frame(usig, ksig, cset, regs); |
050902c0 | 620 | } else if (is_x32_frame()) { |
235b8022 | 621 | return x32_setup_rt_frame(ksig, cset, regs); |
c5a37394 | 622 | } else { |
235b8022 | 623 | return __setup_rt_frame(ksig->sig, ksig, set, regs); |
c5a37394 | 624 | } |
1d13024e HS |
625 | } |
626 | ||
a610d6e6 | 627 | static void |
235b8022 | 628 | handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
1da177e4 | 629 | { |
235b8022 | 630 | bool failed; |
1da177e4 | 631 | /* Are we from a system call? */ |
bb57925f | 632 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 633 | /* If so, check system call restarting.. */ |
bb57925f | 634 | switch (syscall_get_error(current, regs)) { |
ac66f3fd HH |
635 | case -ERESTART_RESTARTBLOCK: |
636 | case -ERESTARTNOHAND: | |
637 | regs->ax = -EINTR; | |
638 | break; | |
639 | ||
640 | case -ERESTARTSYS: | |
235b8022 | 641 | if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
65ea5b03 | 642 | regs->ax = -EINTR; |
1da177e4 | 643 | break; |
ac66f3fd HH |
644 | } |
645 | /* fallthrough */ | |
646 | case -ERESTARTNOINTR: | |
647 | regs->ax = regs->orig_ax; | |
648 | regs->ip -= 2; | |
649 | break; | |
1da177e4 LT |
650 | } |
651 | } | |
652 | ||
653 | /* | |
e1f28773 RM |
654 | * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF |
655 | * flag so that register information in the sigcontext is correct. | |
1da177e4 | 656 | */ |
65ea5b03 | 657 | if (unlikely(regs->flags & X86_EFLAGS_TF) && |
e1f28773 | 658 | likely(test_and_clear_thread_flag(TIF_FORCED_TF))) |
65ea5b03 | 659 | regs->flags &= ~X86_EFLAGS_TF; |
1da177e4 | 660 | |
235b8022 AV |
661 | failed = (setup_rt_frame(ksig, regs) < 0); |
662 | if (!failed) { | |
663 | /* | |
664 | * Clear the direction flag as per the ABI for function entry. | |
ddd40da4 | 665 | * |
24cda109 JO |
666 | * Clear RF when entering the signal handler, because |
667 | * it might disable possible debug exception from the | |
668 | * signal handler. | |
ddd40da4 | 669 | * |
235b8022 AV |
670 | * Clear TF when entering the signal handler, but |
671 | * notify any tracer that was single-stepping it. | |
672 | * The tracer may want to single-step inside the | |
673 | * handler too. | |
674 | */ | |
ddd40da4 | 675 | regs->flags &= ~(X86_EFLAGS_DF|X86_EFLAGS_RF|X86_EFLAGS_TF); |
a610d6e6 | 676 | } |
235b8022 | 677 | signal_setup_done(failed, ksig, test_thread_flag(TIF_SINGLESTEP)); |
1da177e4 LT |
678 | } |
679 | ||
57917752 | 680 | #ifdef CONFIG_X86_32 |
8fcd8e20 | 681 | #define NR_restart_syscall __NR_restart_syscall |
57917752 HS |
682 | #else /* !CONFIG_X86_32 */ |
683 | #define NR_restart_syscall \ | |
684 | test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall | |
685 | #endif /* CONFIG_X86_32 */ | |
686 | ||
1da177e4 LT |
687 | /* |
688 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
689 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
690 | * mistake. | |
691 | */ | |
75604d7f | 692 | static void do_signal(struct pt_regs *regs) |
1da177e4 | 693 | { |
235b8022 | 694 | struct ksignal ksig; |
1da177e4 | 695 | |
235b8022 | 696 | if (get_signal(&ksig)) { |
7e907f48 | 697 | /* Whee! Actually deliver the signal. */ |
235b8022 | 698 | handle_signal(&ksig, regs); |
283828f3 | 699 | return; |
1da177e4 LT |
700 | } |
701 | ||
1da177e4 | 702 | /* Did we come from a system call? */ |
bb57925f | 703 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 704 | /* Restart the system call - no handlers present */ |
bb57925f | 705 | switch (syscall_get_error(current, regs)) { |
283828f3 DH |
706 | case -ERESTARTNOHAND: |
707 | case -ERESTARTSYS: | |
708 | case -ERESTARTNOINTR: | |
65ea5b03 PA |
709 | regs->ax = regs->orig_ax; |
710 | regs->ip -= 2; | |
283828f3 DH |
711 | break; |
712 | ||
713 | case -ERESTART_RESTARTBLOCK: | |
8fcd8e20 | 714 | regs->ax = NR_restart_syscall; |
65ea5b03 | 715 | regs->ip -= 2; |
283828f3 | 716 | break; |
1da177e4 LT |
717 | } |
718 | } | |
283828f3 | 719 | |
ac66f3fd HH |
720 | /* |
721 | * If there's no signal to deliver, we just put the saved sigmask | |
722 | * back. | |
723 | */ | |
51a7b448 | 724 | restore_saved_sigmask(); |
1da177e4 LT |
725 | } |
726 | ||
727 | /* | |
728 | * notification of userspace execution resumption | |
283828f3 | 729 | * - triggered by the TIF_WORK_MASK flags |
1da177e4 | 730 | */ |
277d5b40 | 731 | __visible void |
7e907f48 | 732 | do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) |
1da177e4 | 733 | { |
91d1aa43 | 734 | user_exit(); |
edf55fda | 735 | |
c1ebf835 | 736 | #ifdef CONFIG_X86_MCE |
ee847c54 HS |
737 | /* notify userspace of pending MCEs */ |
738 | if (thread_info_flags & _TIF_MCE_NOTIFY) | |
9b1beaf2 | 739 | mce_notify_process(); |
ee847c54 HS |
740 | #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ |
741 | ||
db023ea5 | 742 | if (thread_info_flags & _TIF_UPROBE) |
0326f5a9 | 743 | uprobe_notify_resume(regs); |
0326f5a9 | 744 | |
1da177e4 | 745 | /* deal with pending signal delivery */ |
5a8da0ea | 746 | if (thread_info_flags & _TIF_SIGPENDING) |
283828f3 | 747 | do_signal(regs); |
8f4d37ec | 748 | |
59e52130 RM |
749 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { |
750 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
751 | tracehook_notify_resume(regs); | |
752 | } | |
7c68af6e AK |
753 | if (thread_info_flags & _TIF_USER_RETURN_NOTIFY) |
754 | fire_user_return_notifiers(); | |
59e52130 | 755 | |
91d1aa43 | 756 | user_enter(); |
1da177e4 | 757 | } |
72fa50f4 HS |
758 | |
759 | void signal_fault(struct pt_regs *regs, void __user *frame, char *where) | |
760 | { | |
761 | struct task_struct *me = current; | |
762 | ||
763 | if (show_unhandled_signals && printk_ratelimit()) { | |
ae417bb4 | 764 | printk("%s" |
72fa50f4 | 765 | "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx", |
ae417bb4 | 766 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
72fa50f4 HS |
767 | me->comm, me->pid, where, frame, |
768 | regs->ip, regs->sp, regs->orig_ax); | |
769 | print_vma_addr(" in ", regs->ip); | |
c767a54b | 770 | pr_cont("\n"); |
72fa50f4 HS |
771 | } |
772 | ||
773 | force_sig(SIGSEGV, me); | |
774 | } | |
c5a37394 PA |
775 | |
776 | #ifdef CONFIG_X86_X32_ABI | |
3fe26fa3 | 777 | asmlinkage long sys32_x32_rt_sigreturn(void) |
c5a37394 | 778 | { |
3fe26fa3 | 779 | struct pt_regs *regs = current_pt_regs(); |
c5a37394 PA |
780 | struct rt_sigframe_x32 __user *frame; |
781 | sigset_t set; | |
782 | unsigned long ax; | |
c5a37394 PA |
783 | |
784 | frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8); | |
785 | ||
786 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
787 | goto badframe; | |
788 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
789 | goto badframe; | |
790 | ||
c5a37394 PA |
791 | set_current_blocked(&set); |
792 | ||
793 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) | |
794 | goto badframe; | |
795 | ||
90268439 | 796 | if (compat_restore_altstack(&frame->uc.uc_stack)) |
c5a37394 PA |
797 | goto badframe; |
798 | ||
799 | return ax; | |
800 | ||
801 | badframe: | |
802 | signal_fault(regs, frame, "x32 rt_sigreturn"); | |
803 | return 0; | |
804 | } | |
805 | #endif |