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> | |
78f7f1e5 | 29 | #include <asm/fpu/internal.h> |
fcbc99c4 | 30 | #include <asm/fpu/signal.h> |
6c3652ef | 31 | #include <asm/vdso.h> |
4efc0670 | 32 | #include <asm/mce.h> |
f28f0c23 | 33 | #include <asm/sighandling.h> |
ba3e127e | 34 | #include <asm/vm86.h> |
5c9b3a0c HS |
35 | |
36 | #ifdef CONFIG_X86_64 | |
37 | #include <asm/proto.h> | |
38 | #include <asm/ia32_unistd.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 | |
6a3713f0 | 64 | int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) |
2601657d | 65 | { |
530e5c82 | 66 | unsigned long buf_val; |
2601657d HS |
67 | void __user *buf; |
68 | unsigned int tmpflags; | |
69 | unsigned int err = 0; | |
70 | ||
71 | /* Always make any pending restarted system calls return -EINTR */ | |
f56141e3 | 72 | current->restart_block.fn = do_no_restart_syscall; |
2601657d | 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 | 83 | COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); |
6a3713f0 | 84 | COPY(dx); COPY(cx); COPY(ip); COPY(ax); |
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 | ||
ed596cde | 97 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
98 | COPY_SEG_CPL3(cs); |
99 | COPY_SEG_CPL3(ss); | |
ed596cde LT |
100 | #else /* !CONFIG_X86_32 */ |
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); | |
105 | #endif /* CONFIG_X86_32 */ | |
2601657d | 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 | ||
530e5c82 IM |
111 | get_user_ex(buf_val, &sc->fpstate); |
112 | buf = (void __user *)buf_val; | |
98e3d45e | 113 | } get_user_catch(err); |
2601657d | 114 | |
9dfe99b7 | 115 | err |= fpu__restore_sig(buf, config_enabled(CONFIG_X86_32)); |
5e88353d | 116 | |
1daeaa31 BG |
117 | force_iret(); |
118 | ||
2601657d HS |
119 | return err; |
120 | } | |
121 | ||
85139422 PA |
122 | int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, |
123 | struct pt_regs *regs, unsigned long mask) | |
2601657d HS |
124 | { |
125 | int err = 0; | |
126 | ||
98e3d45e | 127 | put_user_try { |
2601657d | 128 | |
98e3d45e | 129 | #ifdef CONFIG_X86_32 |
d9a89a26 | 130 | put_user_ex(get_user_gs(regs), (unsigned int __user *)&sc->gs); |
98e3d45e HS |
131 | put_user_ex(regs->fs, (unsigned int __user *)&sc->fs); |
132 | put_user_ex(regs->es, (unsigned int __user *)&sc->es); | |
133 | put_user_ex(regs->ds, (unsigned int __user *)&sc->ds); | |
2601657d HS |
134 | #endif /* CONFIG_X86_32 */ |
135 | ||
98e3d45e HS |
136 | put_user_ex(regs->di, &sc->di); |
137 | put_user_ex(regs->si, &sc->si); | |
138 | put_user_ex(regs->bp, &sc->bp); | |
139 | put_user_ex(regs->sp, &sc->sp); | |
140 | put_user_ex(regs->bx, &sc->bx); | |
141 | put_user_ex(regs->dx, &sc->dx); | |
142 | put_user_ex(regs->cx, &sc->cx); | |
143 | put_user_ex(regs->ax, &sc->ax); | |
2601657d | 144 | #ifdef CONFIG_X86_64 |
98e3d45e HS |
145 | put_user_ex(regs->r8, &sc->r8); |
146 | put_user_ex(regs->r9, &sc->r9); | |
147 | put_user_ex(regs->r10, &sc->r10); | |
148 | put_user_ex(regs->r11, &sc->r11); | |
149 | put_user_ex(regs->r12, &sc->r12); | |
150 | put_user_ex(regs->r13, &sc->r13); | |
151 | put_user_ex(regs->r14, &sc->r14); | |
152 | put_user_ex(regs->r15, &sc->r15); | |
2601657d HS |
153 | #endif /* CONFIG_X86_64 */ |
154 | ||
51e7dc70 | 155 | put_user_ex(current->thread.trap_nr, &sc->trapno); |
98e3d45e HS |
156 | put_user_ex(current->thread.error_code, &sc->err); |
157 | put_user_ex(regs->ip, &sc->ip); | |
2601657d | 158 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
159 | put_user_ex(regs->cs, (unsigned int __user *)&sc->cs); |
160 | put_user_ex(regs->flags, &sc->flags); | |
161 | put_user_ex(regs->sp, &sc->sp_at_signal); | |
162 | put_user_ex(regs->ss, (unsigned int __user *)&sc->ss); | |
2601657d | 163 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
164 | put_user_ex(regs->flags, &sc->flags); |
165 | put_user_ex(regs->cs, &sc->cs); | |
ed596cde LT |
166 | put_user_ex(0, &sc->gs); |
167 | put_user_ex(0, &sc->fs); | |
2601657d HS |
168 | #endif /* CONFIG_X86_32 */ |
169 | ||
98e3d45e | 170 | put_user_ex(fpstate, &sc->fpstate); |
2601657d | 171 | |
98e3d45e HS |
172 | /* non-iBCS2 extensions.. */ |
173 | put_user_ex(mask, &sc->oldmask); | |
174 | put_user_ex(current->thread.cr2, &sc->cr2); | |
175 | } put_user_catch(err); | |
2601657d HS |
176 | |
177 | return err; | |
178 | } | |
179 | ||
1da177e4 | 180 | /* |
bfeb91a9 | 181 | * Set up a signal frame. |
1da177e4 | 182 | */ |
1da177e4 LT |
183 | |
184 | /* | |
185 | * Determine which stack to use.. | |
186 | */ | |
1fae0279 HS |
187 | static unsigned long align_sigframe(unsigned long sp) |
188 | { | |
189 | #ifdef CONFIG_X86_32 | |
190 | /* | |
191 | * Align the stack pointer according to the i386 ABI, | |
192 | * i.e. so that on function entry ((sp + 4) & 15) == 0. | |
193 | */ | |
194 | sp = ((sp + 4) & -16ul) - 4; | |
195 | #else /* !CONFIG_X86_32 */ | |
196 | sp = round_down(sp, 16) - 8; | |
197 | #endif | |
198 | return sp; | |
199 | } | |
200 | ||
dae0f305 | 201 | static void __user * |
3c1c7f10 | 202 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, |
144b0712 | 203 | void __user **fpstate) |
1da177e4 | 204 | { |
1da177e4 | 205 | /* Default to using normal stack */ |
72a671ce | 206 | unsigned long math_size = 0; |
75779f05 | 207 | unsigned long sp = regs->sp; |
72a671ce | 208 | unsigned long buf_fx = 0; |
14fc9fbc | 209 | int onsigstack = on_sig_stack(sp); |
c5bedc68 | 210 | struct fpu *fpu = ¤t->thread.fpu; |
75779f05 | 211 | |
75779f05 | 212 | /* redzone */ |
050902c0 SS |
213 | if (config_enabled(CONFIG_X86_64)) |
214 | sp -= 128; | |
1da177e4 | 215 | |
14fc9fbc HS |
216 | if (!onsigstack) { |
217 | /* This is the X/Open sanctioned signal stack switching. */ | |
218 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
0f8f3089 | 219 | if (current->sas_ss_size) |
14fc9fbc | 220 | sp = current->sas_ss_sp + current->sas_ss_size; |
050902c0 SS |
221 | } else if (config_enabled(CONFIG_X86_32) && |
222 | (regs->ss & 0xffff) != __USER_DS && | |
223 | !(ka->sa.sa_flags & SA_RESTORER) && | |
224 | ka->sa.sa_restorer) { | |
225 | /* This is the legacy signal stack switching. */ | |
14fc9fbc | 226 | sp = (unsigned long) ka->sa.sa_restorer; |
14fc9fbc | 227 | } |
1da177e4 LT |
228 | } |
229 | ||
c5bedc68 | 230 | if (fpu->fpstate_active) { |
82c0e45e IM |
231 | sp = fpu__alloc_mathframe(sp, config_enabled(CONFIG_X86_32), |
232 | &buf_fx, &math_size); | |
25051702 | 233 | *fpstate = (void __user *)sp; |
3c1c7f10 SS |
234 | } |
235 | ||
14fc9fbc HS |
236 | sp = align_sigframe(sp - frame_size); |
237 | ||
238 | /* | |
239 | * If we are on the alternate signal stack and would overflow it, don't. | |
240 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
241 | */ | |
242 | if (onsigstack && !likely(on_sig_stack(sp))) | |
243 | return (void __user *)-1L; | |
244 | ||
72a671ce | 245 | /* save i387 and extended state */ |
c5bedc68 | 246 | if (fpu->fpstate_active && |
c8e14041 | 247 | copy_fpstate_to_sigframe(*fpstate, (void __user *)buf_fx, math_size) < 0) |
14fc9fbc HS |
248 | return (void __user *)-1L; |
249 | ||
250 | return (void __user *)sp; | |
1da177e4 LT |
251 | } |
252 | ||
75779f05 HS |
253 | #ifdef CONFIG_X86_32 |
254 | static const struct { | |
255 | u16 poplmovl; | |
256 | u32 val; | |
257 | u16 int80; | |
258 | } __attribute__((packed)) retcode = { | |
259 | 0xb858, /* popl %eax; movl $..., %eax */ | |
260 | __NR_sigreturn, | |
261 | 0x80cd, /* int $0x80 */ | |
262 | }; | |
263 | ||
264 | static const struct { | |
265 | u8 movl; | |
266 | u32 val; | |
267 | u16 int80; | |
268 | u8 pad; | |
269 | } __attribute__((packed)) rt_retcode = { | |
270 | 0xb8, /* movl $..., %eax */ | |
271 | __NR_rt_sigreturn, | |
272 | 0x80cd, /* int $0x80 */ | |
273 | 0 | |
274 | }; | |
275 | ||
7e907f48 | 276 | static int |
235b8022 | 277 | __setup_frame(int sig, struct ksignal *ksig, sigset_t *set, |
1d13024e | 278 | struct pt_regs *regs) |
1da177e4 | 279 | { |
1da177e4 | 280 | struct sigframe __user *frame; |
7e907f48 | 281 | void __user *restorer; |
1da177e4 | 282 | int err = 0; |
ab513701 | 283 | void __user *fpstate = NULL; |
1da177e4 | 284 | |
235b8022 | 285 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
286 | |
287 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 288 | return -EFAULT; |
1da177e4 | 289 | |
2ba48e16 | 290 | if (__put_user(sig, &frame->sig)) |
3d0aedd9 | 291 | return -EFAULT; |
1da177e4 | 292 | |
2ba48e16 | 293 | if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0])) |
3d0aedd9 | 294 | return -EFAULT; |
1da177e4 LT |
295 | |
296 | if (_NSIG_WORDS > 1) { | |
2ba48e16 HS |
297 | if (__copy_to_user(&frame->extramask, &set->sig[1], |
298 | sizeof(frame->extramask))) | |
3d0aedd9 | 299 | return -EFAULT; |
1da177e4 LT |
300 | } |
301 | ||
1a3e4ca4 | 302 | if (current->mm->context.vdso) |
6f121e54 | 303 | restorer = current->mm->context.vdso + |
0a6d1fa0 | 304 | vdso_image_32.sym___kernel_sigreturn; |
9fbbd4dd | 305 | else |
ade1af77 | 306 | restorer = &frame->retcode; |
235b8022 AV |
307 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
308 | restorer = ksig->ka.sa.sa_restorer; | |
1da177e4 LT |
309 | |
310 | /* Set up to return from userspace. */ | |
311 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 312 | |
1da177e4 | 313 | /* |
7e907f48 | 314 | * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 |
1da177e4 LT |
315 | * |
316 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
317 | * reasons and because gdb uses it as a signature to notice | |
318 | * signal handler stack frames. | |
319 | */ | |
4a612048 | 320 | err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode); |
1da177e4 LT |
321 | |
322 | if (err) | |
3d0aedd9 | 323 | return -EFAULT; |
1da177e4 LT |
324 | |
325 | /* Set up registers for signal handler */ | |
7e907f48 | 326 | regs->sp = (unsigned long)frame; |
235b8022 | 327 | regs->ip = (unsigned long)ksig->ka.sa.sa_handler; |
7e907f48 | 328 | regs->ax = (unsigned long)sig; |
92bc2056 HH |
329 | regs->dx = 0; |
330 | regs->cx = 0; | |
1da177e4 | 331 | |
65ea5b03 PA |
332 | regs->ds = __USER_DS; |
333 | regs->es = __USER_DS; | |
334 | regs->ss = __USER_DS; | |
335 | regs->cs = __USER_CS; | |
1da177e4 | 336 | |
283828f3 | 337 | return 0; |
1da177e4 LT |
338 | } |
339 | ||
235b8022 | 340 | static int __setup_rt_frame(int sig, struct ksignal *ksig, |
1d13024e | 341 | sigset_t *set, struct pt_regs *regs) |
1da177e4 | 342 | { |
1da177e4 | 343 | struct rt_sigframe __user *frame; |
7e907f48 | 344 | void __user *restorer; |
1da177e4 | 345 | int err = 0; |
ab513701 | 346 | void __user *fpstate = NULL; |
1da177e4 | 347 | |
235b8022 | 348 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
349 | |
350 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 351 | return -EFAULT; |
1da177e4 | 352 | |
98e3d45e HS |
353 | put_user_try { |
354 | put_user_ex(sig, &frame->sig); | |
355 | put_user_ex(&frame->info, &frame->pinfo); | |
356 | put_user_ex(&frame->uc, &frame->puc); | |
98e3d45e HS |
357 | |
358 | /* Create the ucontext. */ | |
359 | if (cpu_has_xsave) | |
360 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
361 | else | |
362 | put_user_ex(0, &frame->uc.uc_flags); | |
363 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 364 | save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
98e3d45e HS |
365 | |
366 | /* Set up to return from userspace. */ | |
6f121e54 | 367 | restorer = current->mm->context.vdso + |
0a6d1fa0 | 368 | vdso_image_32.sym___kernel_rt_sigreturn; |
235b8022 AV |
369 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
370 | restorer = ksig->ka.sa.sa_restorer; | |
98e3d45e HS |
371 | put_user_ex(restorer, &frame->pretcode); |
372 | ||
373 | /* | |
374 | * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 | |
375 | * | |
376 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
377 | * reasons and because gdb uses it as a signature to notice | |
378 | * signal handler stack frames. | |
379 | */ | |
380 | put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode); | |
381 | } put_user_catch(err); | |
49b8c695 | 382 | |
235b8022 | 383 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); |
5e88353d PA |
384 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
385 | regs, set->sig[0]); | |
386 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
1da177e4 LT |
387 | |
388 | if (err) | |
3d0aedd9 | 389 | return -EFAULT; |
1da177e4 LT |
390 | |
391 | /* Set up registers for signal handler */ | |
7e907f48 | 392 | regs->sp = (unsigned long)frame; |
235b8022 | 393 | regs->ip = (unsigned long)ksig->ka.sa.sa_handler; |
13ad7725 | 394 | regs->ax = (unsigned long)sig; |
7e907f48 IM |
395 | regs->dx = (unsigned long)&frame->info; |
396 | regs->cx = (unsigned long)&frame->uc; | |
1da177e4 | 397 | |
65ea5b03 PA |
398 | regs->ds = __USER_DS; |
399 | regs->es = __USER_DS; | |
400 | regs->ss = __USER_DS; | |
401 | regs->cs = __USER_CS; | |
1da177e4 | 402 | |
283828f3 | 403 | return 0; |
1da177e4 | 404 | } |
bfeb91a9 | 405 | #else /* !CONFIG_X86_32 */ |
235b8022 | 406 | static int __setup_rt_frame(int sig, struct ksignal *ksig, |
bfeb91a9 HS |
407 | sigset_t *set, struct pt_regs *regs) |
408 | { | |
409 | struct rt_sigframe __user *frame; | |
410 | void __user *fp = NULL; | |
411 | int err = 0; | |
bfeb91a9 | 412 | |
235b8022 | 413 | frame = get_sigframe(&ksig->ka, regs, sizeof(struct rt_sigframe), &fp); |
bfeb91a9 HS |
414 | |
415 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
416 | return -EFAULT; | |
417 | ||
235b8022 AV |
418 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
419 | if (copy_siginfo_to_user(&frame->info, &ksig->info)) | |
bfeb91a9 HS |
420 | return -EFAULT; |
421 | } | |
422 | ||
98e3d45e HS |
423 | put_user_try { |
424 | /* Create the ucontext. */ | |
425 | if (cpu_has_xsave) | |
426 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
427 | else | |
428 | put_user_ex(0, &frame->uc.uc_flags); | |
429 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 430 | save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
98e3d45e HS |
431 | |
432 | /* Set up to return from userspace. If provided, use a stub | |
433 | already in userspace. */ | |
434 | /* x86-64 should always use SA_RESTORER. */ | |
235b8022 AV |
435 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
436 | put_user_ex(ksig->ka.sa.sa_restorer, &frame->pretcode); | |
98e3d45e HS |
437 | } else { |
438 | /* could use a vstub here */ | |
439 | err |= -EFAULT; | |
440 | } | |
441 | } put_user_catch(err); | |
bfeb91a9 | 442 | |
5e88353d PA |
443 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]); |
444 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
445 | ||
bfeb91a9 HS |
446 | if (err) |
447 | return -EFAULT; | |
448 | ||
449 | /* Set up registers for signal handler */ | |
450 | regs->di = sig; | |
451 | /* In case the signal handler was declared without prototypes */ | |
452 | regs->ax = 0; | |
453 | ||
454 | /* This also works for non SA_SIGINFO handlers because they expect the | |
455 | next argument after the signal number on the stack. */ | |
456 | regs->si = (unsigned long)&frame->info; | |
457 | regs->dx = (unsigned long)&frame->uc; | |
235b8022 | 458 | regs->ip = (unsigned long) ksig->ka.sa.sa_handler; |
bfeb91a9 HS |
459 | |
460 | regs->sp = (unsigned long)frame; | |
461 | ||
ed596cde LT |
462 | /* Set up the CS register to run signal handlers in 64-bit mode, |
463 | even if the handler happens to be interrupting 32-bit code. */ | |
bfeb91a9 HS |
464 | regs->cs = __USER_CS; |
465 | ||
466 | return 0; | |
467 | } | |
468 | #endif /* CONFIG_X86_32 */ | |
469 | ||
235b8022 AV |
470 | static int x32_setup_rt_frame(struct ksignal *ksig, |
471 | compat_sigset_t *set, | |
050902c0 SS |
472 | struct pt_regs *regs) |
473 | { | |
474 | #ifdef CONFIG_X86_X32_ABI | |
475 | struct rt_sigframe_x32 __user *frame; | |
476 | void __user *restorer; | |
477 | int err = 0; | |
478 | void __user *fpstate = NULL; | |
479 | ||
235b8022 | 480 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
050902c0 SS |
481 | |
482 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
483 | return -EFAULT; | |
484 | ||
235b8022 AV |
485 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
486 | if (copy_siginfo_to_user32(&frame->info, &ksig->info)) | |
050902c0 SS |
487 | return -EFAULT; |
488 | } | |
489 | ||
490 | put_user_try { | |
491 | /* Create the ucontext. */ | |
492 | if (cpu_has_xsave) | |
493 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
494 | else | |
495 | put_user_ex(0, &frame->uc.uc_flags); | |
496 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 497 | compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
050902c0 | 498 | put_user_ex(0, &frame->uc.uc__pad0); |
050902c0 | 499 | |
235b8022 AV |
500 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
501 | restorer = ksig->ka.sa.sa_restorer; | |
050902c0 SS |
502 | } else { |
503 | /* could use a vstub here */ | |
504 | restorer = NULL; | |
505 | err |= -EFAULT; | |
506 | } | |
507 | put_user_ex(restorer, &frame->pretcode); | |
508 | } put_user_catch(err); | |
509 | ||
49b8c695 PA |
510 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
511 | regs, set->sig[0]); | |
512 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
513 | ||
050902c0 SS |
514 | if (err) |
515 | return -EFAULT; | |
516 | ||
517 | /* Set up registers for signal handler */ | |
518 | regs->sp = (unsigned long) frame; | |
235b8022 | 519 | regs->ip = (unsigned long) ksig->ka.sa.sa_handler; |
050902c0 SS |
520 | |
521 | /* We use the x32 calling convention here... */ | |
235b8022 | 522 | regs->di = ksig->sig; |
050902c0 SS |
523 | regs->si = (unsigned long) &frame->info; |
524 | regs->dx = (unsigned long) &frame->uc; | |
525 | ||
526 | loadsegment(ds, __USER_DS); | |
527 | loadsegment(es, __USER_DS); | |
528 | ||
529 | regs->cs = __USER_CS; | |
530 | regs->ss = __USER_DS; | |
531 | #endif /* CONFIG_X86_X32_ABI */ | |
532 | ||
533 | return 0; | |
534 | } | |
535 | ||
bfeb91a9 HS |
536 | /* |
537 | * Do a signal return; undo the signal stack. | |
538 | */ | |
e5fa2d06 | 539 | #ifdef CONFIG_X86_32 |
ff49103f | 540 | asmlinkage unsigned long sys_sigreturn(void) |
bfeb91a9 | 541 | { |
3fe26fa3 | 542 | struct pt_regs *regs = current_pt_regs(); |
bfeb91a9 | 543 | struct sigframe __user *frame; |
bfeb91a9 HS |
544 | sigset_t set; |
545 | ||
bfeb91a9 HS |
546 | frame = (struct sigframe __user *)(regs->sp - 8); |
547 | ||
548 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
549 | goto badframe; | |
550 | if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1 | |
551 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
552 | sizeof(frame->extramask)))) | |
553 | goto badframe; | |
554 | ||
3982294b | 555 | set_current_blocked(&set); |
bfeb91a9 | 556 | |
6a3713f0 | 557 | if (restore_sigcontext(regs, &frame->sc)) |
bfeb91a9 | 558 | goto badframe; |
6a3713f0 | 559 | return regs->ax; |
bfeb91a9 HS |
560 | |
561 | badframe: | |
ae417bb4 | 562 | signal_fault(regs, frame, "sigreturn"); |
bfeb91a9 HS |
563 | |
564 | return 0; | |
565 | } | |
e5fa2d06 | 566 | #endif /* CONFIG_X86_32 */ |
bfeb91a9 | 567 | |
ff49103f | 568 | asmlinkage long sys_rt_sigreturn(void) |
bfeb91a9 | 569 | { |
3fe26fa3 | 570 | struct pt_regs *regs = current_pt_regs(); |
bfeb91a9 | 571 | struct rt_sigframe __user *frame; |
bfeb91a9 HS |
572 | sigset_t set; |
573 | ||
574 | frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); | |
575 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
576 | goto badframe; | |
577 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
578 | goto badframe; | |
579 | ||
e9bd3f0f | 580 | set_current_blocked(&set); |
bfeb91a9 | 581 | |
6a3713f0 | 582 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) |
bfeb91a9 HS |
583 | goto badframe; |
584 | ||
c40702c4 | 585 | if (restore_altstack(&frame->uc.uc_stack)) |
bfeb91a9 HS |
586 | goto badframe; |
587 | ||
6a3713f0 | 588 | return regs->ax; |
bfeb91a9 HS |
589 | |
590 | badframe: | |
591 | signal_fault(regs, frame, "rt_sigreturn"); | |
592 | return 0; | |
593 | } | |
594 | ||
05012c13 IM |
595 | static inline int is_ia32_compat_frame(void) |
596 | { | |
597 | return config_enabled(CONFIG_IA32_EMULATION) && | |
598 | test_thread_flag(TIF_IA32); | |
599 | } | |
600 | ||
601 | static inline int is_ia32_frame(void) | |
602 | { | |
603 | return config_enabled(CONFIG_X86_32) || is_ia32_compat_frame(); | |
604 | } | |
605 | ||
606 | static inline int is_x32_frame(void) | |
607 | { | |
608 | return config_enabled(CONFIG_X86_X32_ABI) && test_thread_flag(TIF_X32); | |
609 | } | |
610 | ||
1d13024e | 611 | static int |
235b8022 | 612 | setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) |
1d13024e | 613 | { |
3050a35f | 614 | int usig = ksig->sig; |
b7f9a11a | 615 | sigset_t *set = sigmask_to_save(); |
050902c0 | 616 | compat_sigset_t *cset = (compat_sigset_t *) set; |
1d13024e HS |
617 | |
618 | /* Set up the stack frame */ | |
050902c0 | 619 | if (is_ia32_frame()) { |
235b8022 AV |
620 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
621 | return ia32_setup_rt_frame(usig, ksig, cset, regs); | |
455edbc4 | 622 | else |
235b8022 | 623 | return ia32_setup_frame(usig, ksig, cset, regs); |
050902c0 | 624 | } else if (is_x32_frame()) { |
235b8022 | 625 | return x32_setup_rt_frame(ksig, cset, regs); |
c5a37394 | 626 | } else { |
235b8022 | 627 | return __setup_rt_frame(ksig->sig, ksig, set, regs); |
c5a37394 | 628 | } |
1d13024e HS |
629 | } |
630 | ||
a610d6e6 | 631 | static void |
235b8022 | 632 | handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
1da177e4 | 633 | { |
fd0f86b6 | 634 | bool stepping, failed; |
c5bedc68 | 635 | struct fpu *fpu = ¤t->thread.fpu; |
fd0f86b6 | 636 | |
5ed92a8a BG |
637 | if (v8086_mode(regs)) |
638 | save_v86_state((struct kernel_vm86_regs *) regs, VM86_SIGNAL); | |
639 | ||
1da177e4 | 640 | /* Are we from a system call? */ |
bb57925f | 641 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 642 | /* If so, check system call restarting.. */ |
bb57925f | 643 | switch (syscall_get_error(current, regs)) { |
ac66f3fd HH |
644 | case -ERESTART_RESTARTBLOCK: |
645 | case -ERESTARTNOHAND: | |
646 | regs->ax = -EINTR; | |
647 | break; | |
648 | ||
649 | case -ERESTARTSYS: | |
235b8022 | 650 | if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
65ea5b03 | 651 | regs->ax = -EINTR; |
1da177e4 | 652 | break; |
ac66f3fd HH |
653 | } |
654 | /* fallthrough */ | |
655 | case -ERESTARTNOINTR: | |
656 | regs->ax = regs->orig_ax; | |
657 | regs->ip -= 2; | |
658 | break; | |
1da177e4 LT |
659 | } |
660 | } | |
661 | ||
662 | /* | |
fd0f86b6 ON |
663 | * If TF is set due to a debugger (TIF_FORCED_TF), clear TF now |
664 | * so that register information in the sigcontext is correct and | |
665 | * then notify the tracer before entering the signal handler. | |
1da177e4 | 666 | */ |
fd0f86b6 ON |
667 | stepping = test_thread_flag(TIF_SINGLESTEP); |
668 | if (stepping) | |
669 | user_disable_single_step(current); | |
1da177e4 | 670 | |
235b8022 AV |
671 | failed = (setup_rt_frame(ksig, regs) < 0); |
672 | if (!failed) { | |
673 | /* | |
674 | * Clear the direction flag as per the ABI for function entry. | |
ddd40da4 | 675 | * |
24cda109 JO |
676 | * Clear RF when entering the signal handler, because |
677 | * it might disable possible debug exception from the | |
678 | * signal handler. | |
ddd40da4 | 679 | * |
fd0f86b6 ON |
680 | * Clear TF for the case when it wasn't set by debugger to |
681 | * avoid the recursive send_sigtrap() in SIGTRAP handler. | |
235b8022 | 682 | */ |
ddd40da4 | 683 | regs->flags &= ~(X86_EFLAGS_DF|X86_EFLAGS_RF|X86_EFLAGS_TF); |
66463db4 ON |
684 | /* |
685 | * Ensure the signal handler starts with the new fpu state. | |
686 | */ | |
c5bedc68 | 687 | if (fpu->fpstate_active) |
fbce7782 | 688 | fpu__clear(fpu); |
a610d6e6 | 689 | } |
fd0f86b6 | 690 | signal_setup_done(failed, ksig, stepping); |
1da177e4 LT |
691 | } |
692 | ||
22eab110 DL |
693 | static inline unsigned long get_nr_restart_syscall(const struct pt_regs *regs) |
694 | { | |
695 | #if defined(CONFIG_X86_32) || !defined(CONFIG_X86_64) | |
696 | return __NR_restart_syscall; | |
697 | #else /* !CONFIG_X86_32 && CONFIG_X86_64 */ | |
698 | return test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : | |
699 | __NR_restart_syscall | (regs->orig_ax & __X32_SYSCALL_BIT); | |
700 | #endif /* CONFIG_X86_32 || !CONFIG_X86_64 */ | |
701 | } | |
57917752 | 702 | |
1da177e4 LT |
703 | /* |
704 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
705 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
706 | * mistake. | |
707 | */ | |
1f484aa6 | 708 | void do_signal(struct pt_regs *regs) |
1da177e4 | 709 | { |
235b8022 | 710 | struct ksignal ksig; |
1da177e4 | 711 | |
235b8022 | 712 | if (get_signal(&ksig)) { |
7e907f48 | 713 | /* Whee! Actually deliver the signal. */ |
235b8022 | 714 | handle_signal(&ksig, regs); |
283828f3 | 715 | return; |
1da177e4 LT |
716 | } |
717 | ||
1da177e4 | 718 | /* Did we come from a system call? */ |
bb57925f | 719 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 720 | /* Restart the system call - no handlers present */ |
bb57925f | 721 | switch (syscall_get_error(current, regs)) { |
283828f3 DH |
722 | case -ERESTARTNOHAND: |
723 | case -ERESTARTSYS: | |
724 | case -ERESTARTNOINTR: | |
65ea5b03 PA |
725 | regs->ax = regs->orig_ax; |
726 | regs->ip -= 2; | |
283828f3 DH |
727 | break; |
728 | ||
729 | case -ERESTART_RESTARTBLOCK: | |
22eab110 | 730 | regs->ax = get_nr_restart_syscall(regs); |
65ea5b03 | 731 | regs->ip -= 2; |
283828f3 | 732 | break; |
1da177e4 LT |
733 | } |
734 | } | |
283828f3 | 735 | |
ac66f3fd HH |
736 | /* |
737 | * If there's no signal to deliver, we just put the saved sigmask | |
738 | * back. | |
739 | */ | |
51a7b448 | 740 | restore_saved_sigmask(); |
1da177e4 LT |
741 | } |
742 | ||
72fa50f4 HS |
743 | void signal_fault(struct pt_regs *regs, void __user *frame, char *where) |
744 | { | |
745 | struct task_struct *me = current; | |
746 | ||
747 | if (show_unhandled_signals && printk_ratelimit()) { | |
ae417bb4 | 748 | printk("%s" |
72fa50f4 | 749 | "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx", |
ae417bb4 | 750 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
72fa50f4 HS |
751 | me->comm, me->pid, where, frame, |
752 | regs->ip, regs->sp, regs->orig_ax); | |
753 | print_vma_addr(" in ", regs->ip); | |
c767a54b | 754 | pr_cont("\n"); |
72fa50f4 HS |
755 | } |
756 | ||
757 | force_sig(SIGSEGV, me); | |
758 | } | |
c5a37394 PA |
759 | |
760 | #ifdef CONFIG_X86_X32_ABI | |
3fe26fa3 | 761 | asmlinkage long sys32_x32_rt_sigreturn(void) |
c5a37394 | 762 | { |
3fe26fa3 | 763 | struct pt_regs *regs = current_pt_regs(); |
c5a37394 PA |
764 | struct rt_sigframe_x32 __user *frame; |
765 | sigset_t set; | |
c5a37394 PA |
766 | |
767 | frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8); | |
768 | ||
769 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
770 | goto badframe; | |
771 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
772 | goto badframe; | |
773 | ||
c5a37394 PA |
774 | set_current_blocked(&set); |
775 | ||
6a3713f0 | 776 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) |
c5a37394 PA |
777 | goto badframe; |
778 | ||
90268439 | 779 | if (compat_restore_altstack(&frame->uc.uc_stack)) |
c5a37394 PA |
780 | goto badframe; |
781 | ||
6a3713f0 | 782 | return regs->ax; |
c5a37394 PA |
783 | |
784 | badframe: | |
785 | signal_fault(regs, frame, "x32 rt_sigreturn"); | |
786 | return 0; | |
787 | } | |
788 | #endif |