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Commit | Line | Data |
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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 HS |
65 | { |
66 | void __user *buf; | |
67 | unsigned int tmpflags; | |
68 | unsigned int err = 0; | |
69 | ||
70 | /* Always make any pending restarted system calls return -EINTR */ | |
f56141e3 | 71 | current->restart_block.fn = do_no_restart_syscall; |
2601657d | 72 | |
98e3d45e HS |
73 | get_user_try { |
74 | ||
2601657d | 75 | #ifdef CONFIG_X86_32 |
d9a89a26 | 76 | set_user_gs(regs, GET_SEG(gs)); |
98e3d45e HS |
77 | COPY_SEG(fs); |
78 | COPY_SEG(es); | |
79 | COPY_SEG(ds); | |
2601657d HS |
80 | #endif /* CONFIG_X86_32 */ |
81 | ||
98e3d45e | 82 | COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); |
6a3713f0 | 83 | COPY(dx); COPY(cx); COPY(ip); COPY(ax); |
2601657d HS |
84 | |
85 | #ifdef CONFIG_X86_64 | |
98e3d45e HS |
86 | COPY(r8); |
87 | COPY(r9); | |
88 | COPY(r10); | |
89 | COPY(r11); | |
90 | COPY(r12); | |
91 | COPY(r13); | |
92 | COPY(r14); | |
93 | COPY(r15); | |
2601657d HS |
94 | #endif /* CONFIG_X86_64 */ |
95 | ||
ed596cde | 96 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
97 | COPY_SEG_CPL3(cs); |
98 | COPY_SEG_CPL3(ss); | |
ed596cde LT |
99 | #else /* !CONFIG_X86_32 */ |
100 | /* Kernel saves and restores only the CS segment register on signals, | |
101 | * which is the bare minimum needed to allow mixed 32/64-bit code. | |
102 | * App's signal handler can save/restore other segments if needed. */ | |
103 | COPY_SEG_CPL3(cs); | |
104 | #endif /* CONFIG_X86_32 */ | |
2601657d | 105 | |
98e3d45e HS |
106 | get_user_ex(tmpflags, &sc->flags); |
107 | regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
108 | regs->orig_ax = -1; /* disable syscall checks */ | |
109 | ||
110 | get_user_ex(buf, &sc->fpstate); | |
98e3d45e | 111 | } get_user_catch(err); |
2601657d | 112 | |
9dfe99b7 | 113 | err |= fpu__restore_sig(buf, config_enabled(CONFIG_X86_32)); |
5e88353d | 114 | |
1daeaa31 BG |
115 | force_iret(); |
116 | ||
2601657d HS |
117 | return err; |
118 | } | |
119 | ||
85139422 PA |
120 | int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, |
121 | struct pt_regs *regs, unsigned long mask) | |
2601657d HS |
122 | { |
123 | int err = 0; | |
124 | ||
98e3d45e | 125 | put_user_try { |
2601657d | 126 | |
98e3d45e | 127 | #ifdef CONFIG_X86_32 |
d9a89a26 | 128 | put_user_ex(get_user_gs(regs), (unsigned int __user *)&sc->gs); |
98e3d45e HS |
129 | put_user_ex(regs->fs, (unsigned int __user *)&sc->fs); |
130 | put_user_ex(regs->es, (unsigned int __user *)&sc->es); | |
131 | put_user_ex(regs->ds, (unsigned int __user *)&sc->ds); | |
2601657d HS |
132 | #endif /* CONFIG_X86_32 */ |
133 | ||
98e3d45e HS |
134 | put_user_ex(regs->di, &sc->di); |
135 | put_user_ex(regs->si, &sc->si); | |
136 | put_user_ex(regs->bp, &sc->bp); | |
137 | put_user_ex(regs->sp, &sc->sp); | |
138 | put_user_ex(regs->bx, &sc->bx); | |
139 | put_user_ex(regs->dx, &sc->dx); | |
140 | put_user_ex(regs->cx, &sc->cx); | |
141 | put_user_ex(regs->ax, &sc->ax); | |
2601657d | 142 | #ifdef CONFIG_X86_64 |
98e3d45e HS |
143 | put_user_ex(regs->r8, &sc->r8); |
144 | put_user_ex(regs->r9, &sc->r9); | |
145 | put_user_ex(regs->r10, &sc->r10); | |
146 | put_user_ex(regs->r11, &sc->r11); | |
147 | put_user_ex(regs->r12, &sc->r12); | |
148 | put_user_ex(regs->r13, &sc->r13); | |
149 | put_user_ex(regs->r14, &sc->r14); | |
150 | put_user_ex(regs->r15, &sc->r15); | |
2601657d HS |
151 | #endif /* CONFIG_X86_64 */ |
152 | ||
51e7dc70 | 153 | put_user_ex(current->thread.trap_nr, &sc->trapno); |
98e3d45e HS |
154 | put_user_ex(current->thread.error_code, &sc->err); |
155 | put_user_ex(regs->ip, &sc->ip); | |
2601657d | 156 | #ifdef CONFIG_X86_32 |
98e3d45e HS |
157 | put_user_ex(regs->cs, (unsigned int __user *)&sc->cs); |
158 | put_user_ex(regs->flags, &sc->flags); | |
159 | put_user_ex(regs->sp, &sc->sp_at_signal); | |
160 | put_user_ex(regs->ss, (unsigned int __user *)&sc->ss); | |
2601657d | 161 | #else /* !CONFIG_X86_32 */ |
98e3d45e HS |
162 | put_user_ex(regs->flags, &sc->flags); |
163 | put_user_ex(regs->cs, &sc->cs); | |
ed596cde LT |
164 | put_user_ex(0, &sc->gs); |
165 | put_user_ex(0, &sc->fs); | |
2601657d HS |
166 | #endif /* CONFIG_X86_32 */ |
167 | ||
98e3d45e | 168 | put_user_ex(fpstate, &sc->fpstate); |
2601657d | 169 | |
98e3d45e HS |
170 | /* non-iBCS2 extensions.. */ |
171 | put_user_ex(mask, &sc->oldmask); | |
172 | put_user_ex(current->thread.cr2, &sc->cr2); | |
173 | } put_user_catch(err); | |
2601657d HS |
174 | |
175 | return err; | |
176 | } | |
177 | ||
1da177e4 | 178 | /* |
bfeb91a9 | 179 | * Set up a signal frame. |
1da177e4 | 180 | */ |
1da177e4 LT |
181 | |
182 | /* | |
183 | * Determine which stack to use.. | |
184 | */ | |
1fae0279 HS |
185 | static unsigned long align_sigframe(unsigned long sp) |
186 | { | |
187 | #ifdef CONFIG_X86_32 | |
188 | /* | |
189 | * Align the stack pointer according to the i386 ABI, | |
190 | * i.e. so that on function entry ((sp + 4) & 15) == 0. | |
191 | */ | |
192 | sp = ((sp + 4) & -16ul) - 4; | |
193 | #else /* !CONFIG_X86_32 */ | |
194 | sp = round_down(sp, 16) - 8; | |
195 | #endif | |
196 | return sp; | |
197 | } | |
198 | ||
1da177e4 | 199 | static inline void __user * |
3c1c7f10 | 200 | get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, |
144b0712 | 201 | void __user **fpstate) |
1da177e4 | 202 | { |
1da177e4 | 203 | /* Default to using normal stack */ |
72a671ce | 204 | unsigned long math_size = 0; |
75779f05 | 205 | unsigned long sp = regs->sp; |
72a671ce | 206 | unsigned long buf_fx = 0; |
14fc9fbc | 207 | int onsigstack = on_sig_stack(sp); |
c5bedc68 | 208 | struct fpu *fpu = ¤t->thread.fpu; |
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 | ||
c5bedc68 | 228 | if (fpu->fpstate_active) { |
82c0e45e IM |
229 | sp = fpu__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 | 243 | /* save i387 and extended state */ |
c5bedc68 | 244 | if (fpu->fpstate_active && |
c8e14041 | 245 | copy_fpstate_to_sigframe(*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) |
6f121e54 AL |
301 | restorer = current->mm->context.vdso + |
302 | selected_vdso32->sym___kernel_sigreturn; | |
9fbbd4dd | 303 | else |
ade1af77 | 304 | restorer = &frame->retcode; |
235b8022 AV |
305 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
306 | restorer = ksig->ka.sa.sa_restorer; | |
1da177e4 LT |
307 | |
308 | /* Set up to return from userspace. */ | |
309 | err |= __put_user(restorer, &frame->pretcode); | |
7e907f48 | 310 | |
1da177e4 | 311 | /* |
7e907f48 | 312 | * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80 |
1da177e4 LT |
313 | * |
314 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
315 | * reasons and because gdb uses it as a signature to notice | |
316 | * signal handler stack frames. | |
317 | */ | |
4a612048 | 318 | err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode); |
1da177e4 LT |
319 | |
320 | if (err) | |
3d0aedd9 | 321 | return -EFAULT; |
1da177e4 LT |
322 | |
323 | /* Set up registers for signal handler */ | |
7e907f48 | 324 | regs->sp = (unsigned long)frame; |
235b8022 | 325 | regs->ip = (unsigned long)ksig->ka.sa.sa_handler; |
7e907f48 | 326 | regs->ax = (unsigned long)sig; |
92bc2056 HH |
327 | regs->dx = 0; |
328 | regs->cx = 0; | |
1da177e4 | 329 | |
65ea5b03 PA |
330 | regs->ds = __USER_DS; |
331 | regs->es = __USER_DS; | |
332 | regs->ss = __USER_DS; | |
333 | regs->cs = __USER_CS; | |
1da177e4 | 334 | |
283828f3 | 335 | return 0; |
1da177e4 LT |
336 | } |
337 | ||
235b8022 | 338 | static int __setup_rt_frame(int sig, struct ksignal *ksig, |
1d13024e | 339 | sigset_t *set, struct pt_regs *regs) |
1da177e4 | 340 | { |
1da177e4 | 341 | struct rt_sigframe __user *frame; |
7e907f48 | 342 | void __user *restorer; |
1da177e4 | 343 | int err = 0; |
ab513701 | 344 | void __user *fpstate = NULL; |
1da177e4 | 345 | |
235b8022 | 346 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
1da177e4 LT |
347 | |
348 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
3d0aedd9 | 349 | return -EFAULT; |
1da177e4 | 350 | |
98e3d45e HS |
351 | put_user_try { |
352 | put_user_ex(sig, &frame->sig); | |
353 | put_user_ex(&frame->info, &frame->pinfo); | |
354 | put_user_ex(&frame->uc, &frame->puc); | |
98e3d45e HS |
355 | |
356 | /* Create the ucontext. */ | |
357 | if (cpu_has_xsave) | |
358 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
359 | else | |
360 | put_user_ex(0, &frame->uc.uc_flags); | |
361 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 362 | save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
98e3d45e HS |
363 | |
364 | /* Set up to return from userspace. */ | |
6f121e54 | 365 | restorer = current->mm->context.vdso + |
6ba19a67 | 366 | selected_vdso32->sym___kernel_rt_sigreturn; |
235b8022 AV |
367 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
368 | restorer = ksig->ka.sa.sa_restorer; | |
98e3d45e HS |
369 | put_user_ex(restorer, &frame->pretcode); |
370 | ||
371 | /* | |
372 | * This is movl $__NR_rt_sigreturn, %ax ; int $0x80 | |
373 | * | |
374 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
375 | * reasons and because gdb uses it as a signature to notice | |
376 | * signal handler stack frames. | |
377 | */ | |
378 | put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode); | |
379 | } put_user_catch(err); | |
49b8c695 | 380 | |
235b8022 | 381 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); |
5e88353d PA |
382 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
383 | regs, set->sig[0]); | |
384 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
1da177e4 LT |
385 | |
386 | if (err) | |
3d0aedd9 | 387 | return -EFAULT; |
1da177e4 LT |
388 | |
389 | /* Set up registers for signal handler */ | |
7e907f48 | 390 | regs->sp = (unsigned long)frame; |
235b8022 | 391 | regs->ip = (unsigned long)ksig->ka.sa.sa_handler; |
13ad7725 | 392 | regs->ax = (unsigned long)sig; |
7e907f48 IM |
393 | regs->dx = (unsigned long)&frame->info; |
394 | regs->cx = (unsigned long)&frame->uc; | |
1da177e4 | 395 | |
65ea5b03 PA |
396 | regs->ds = __USER_DS; |
397 | regs->es = __USER_DS; | |
398 | regs->ss = __USER_DS; | |
399 | regs->cs = __USER_CS; | |
1da177e4 | 400 | |
283828f3 | 401 | return 0; |
1da177e4 | 402 | } |
bfeb91a9 | 403 | #else /* !CONFIG_X86_32 */ |
235b8022 | 404 | static int __setup_rt_frame(int sig, struct ksignal *ksig, |
bfeb91a9 HS |
405 | sigset_t *set, struct pt_regs *regs) |
406 | { | |
407 | struct rt_sigframe __user *frame; | |
408 | void __user *fp = NULL; | |
409 | int err = 0; | |
bfeb91a9 | 410 | |
235b8022 | 411 | frame = get_sigframe(&ksig->ka, regs, sizeof(struct rt_sigframe), &fp); |
bfeb91a9 HS |
412 | |
413 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
414 | return -EFAULT; | |
415 | ||
235b8022 AV |
416 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
417 | if (copy_siginfo_to_user(&frame->info, &ksig->info)) | |
bfeb91a9 HS |
418 | return -EFAULT; |
419 | } | |
420 | ||
98e3d45e HS |
421 | put_user_try { |
422 | /* Create the ucontext. */ | |
423 | if (cpu_has_xsave) | |
424 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
425 | else | |
426 | put_user_ex(0, &frame->uc.uc_flags); | |
427 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 428 | save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
98e3d45e HS |
429 | |
430 | /* Set up to return from userspace. If provided, use a stub | |
431 | already in userspace. */ | |
432 | /* x86-64 should always use SA_RESTORER. */ | |
235b8022 AV |
433 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
434 | put_user_ex(ksig->ka.sa.sa_restorer, &frame->pretcode); | |
98e3d45e HS |
435 | } else { |
436 | /* could use a vstub here */ | |
437 | err |= -EFAULT; | |
438 | } | |
439 | } put_user_catch(err); | |
bfeb91a9 | 440 | |
5e88353d PA |
441 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]); |
442 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
443 | ||
bfeb91a9 HS |
444 | if (err) |
445 | return -EFAULT; | |
446 | ||
447 | /* Set up registers for signal handler */ | |
448 | regs->di = sig; | |
449 | /* In case the signal handler was declared without prototypes */ | |
450 | regs->ax = 0; | |
451 | ||
452 | /* This also works for non SA_SIGINFO handlers because they expect the | |
453 | next argument after the signal number on the stack. */ | |
454 | regs->si = (unsigned long)&frame->info; | |
455 | regs->dx = (unsigned long)&frame->uc; | |
235b8022 | 456 | regs->ip = (unsigned long) ksig->ka.sa.sa_handler; |
bfeb91a9 HS |
457 | |
458 | regs->sp = (unsigned long)frame; | |
459 | ||
ed596cde LT |
460 | /* Set up the CS register to run signal handlers in 64-bit mode, |
461 | even if the handler happens to be interrupting 32-bit code. */ | |
bfeb91a9 HS |
462 | regs->cs = __USER_CS; |
463 | ||
464 | return 0; | |
465 | } | |
466 | #endif /* CONFIG_X86_32 */ | |
467 | ||
235b8022 AV |
468 | static int x32_setup_rt_frame(struct ksignal *ksig, |
469 | compat_sigset_t *set, | |
050902c0 SS |
470 | struct pt_regs *regs) |
471 | { | |
472 | #ifdef CONFIG_X86_X32_ABI | |
473 | struct rt_sigframe_x32 __user *frame; | |
474 | void __user *restorer; | |
475 | int err = 0; | |
476 | void __user *fpstate = NULL; | |
477 | ||
235b8022 | 478 | frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fpstate); |
050902c0 SS |
479 | |
480 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
481 | return -EFAULT; | |
482 | ||
235b8022 AV |
483 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
484 | if (copy_siginfo_to_user32(&frame->info, &ksig->info)) | |
050902c0 SS |
485 | return -EFAULT; |
486 | } | |
487 | ||
488 | put_user_try { | |
489 | /* Create the ucontext. */ | |
490 | if (cpu_has_xsave) | |
491 | put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); | |
492 | else | |
493 | put_user_ex(0, &frame->uc.uc_flags); | |
494 | put_user_ex(0, &frame->uc.uc_link); | |
bd1c149a | 495 | compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp); |
050902c0 | 496 | put_user_ex(0, &frame->uc.uc__pad0); |
050902c0 | 497 | |
235b8022 AV |
498 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
499 | restorer = ksig->ka.sa.sa_restorer; | |
050902c0 SS |
500 | } else { |
501 | /* could use a vstub here */ | |
502 | restorer = NULL; | |
503 | err |= -EFAULT; | |
504 | } | |
505 | put_user_ex(restorer, &frame->pretcode); | |
506 | } put_user_catch(err); | |
507 | ||
49b8c695 PA |
508 | err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate, |
509 | regs, set->sig[0]); | |
510 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
511 | ||
050902c0 SS |
512 | if (err) |
513 | return -EFAULT; | |
514 | ||
515 | /* Set up registers for signal handler */ | |
516 | regs->sp = (unsigned long) frame; | |
235b8022 | 517 | regs->ip = (unsigned long) ksig->ka.sa.sa_handler; |
050902c0 SS |
518 | |
519 | /* We use the x32 calling convention here... */ | |
235b8022 | 520 | regs->di = ksig->sig; |
050902c0 SS |
521 | regs->si = (unsigned long) &frame->info; |
522 | regs->dx = (unsigned long) &frame->uc; | |
523 | ||
524 | loadsegment(ds, __USER_DS); | |
525 | loadsegment(es, __USER_DS); | |
526 | ||
527 | regs->cs = __USER_CS; | |
528 | regs->ss = __USER_DS; | |
529 | #endif /* CONFIG_X86_X32_ABI */ | |
530 | ||
531 | return 0; | |
532 | } | |
533 | ||
bfeb91a9 HS |
534 | /* |
535 | * Do a signal return; undo the signal stack. | |
536 | */ | |
e5fa2d06 | 537 | #ifdef CONFIG_X86_32 |
ff49103f | 538 | asmlinkage unsigned long sys_sigreturn(void) |
bfeb91a9 | 539 | { |
3fe26fa3 | 540 | struct pt_regs *regs = current_pt_regs(); |
bfeb91a9 | 541 | struct sigframe __user *frame; |
bfeb91a9 HS |
542 | sigset_t set; |
543 | ||
bfeb91a9 HS |
544 | frame = (struct sigframe __user *)(regs->sp - 8); |
545 | ||
546 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
547 | goto badframe; | |
548 | if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1 | |
549 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
550 | sizeof(frame->extramask)))) | |
551 | goto badframe; | |
552 | ||
3982294b | 553 | set_current_blocked(&set); |
bfeb91a9 | 554 | |
6a3713f0 | 555 | if (restore_sigcontext(regs, &frame->sc)) |
bfeb91a9 | 556 | goto badframe; |
6a3713f0 | 557 | return regs->ax; |
bfeb91a9 HS |
558 | |
559 | badframe: | |
ae417bb4 | 560 | signal_fault(regs, frame, "sigreturn"); |
bfeb91a9 HS |
561 | |
562 | return 0; | |
563 | } | |
e5fa2d06 | 564 | #endif /* CONFIG_X86_32 */ |
bfeb91a9 | 565 | |
ff49103f | 566 | asmlinkage long sys_rt_sigreturn(void) |
bfeb91a9 | 567 | { |
3fe26fa3 | 568 | struct pt_regs *regs = current_pt_regs(); |
bfeb91a9 | 569 | struct rt_sigframe __user *frame; |
bfeb91a9 HS |
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 | 579 | |
6a3713f0 | 580 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) |
bfeb91a9 HS |
581 | goto badframe; |
582 | ||
c40702c4 | 583 | if (restore_altstack(&frame->uc.uc_stack)) |
bfeb91a9 HS |
584 | goto badframe; |
585 | ||
6a3713f0 | 586 | return regs->ax; |
bfeb91a9 HS |
587 | |
588 | badframe: | |
589 | signal_fault(regs, frame, "rt_sigreturn"); | |
590 | return 0; | |
591 | } | |
592 | ||
05012c13 IM |
593 | static inline int is_ia32_compat_frame(void) |
594 | { | |
595 | return config_enabled(CONFIG_IA32_EMULATION) && | |
596 | test_thread_flag(TIF_IA32); | |
597 | } | |
598 | ||
599 | static inline int is_ia32_frame(void) | |
600 | { | |
601 | return config_enabled(CONFIG_X86_32) || is_ia32_compat_frame(); | |
602 | } | |
603 | ||
604 | static inline int is_x32_frame(void) | |
605 | { | |
606 | return config_enabled(CONFIG_X86_X32_ABI) && test_thread_flag(TIF_X32); | |
607 | } | |
608 | ||
1d13024e | 609 | static int |
235b8022 | 610 | setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) |
1d13024e | 611 | { |
3050a35f | 612 | int usig = ksig->sig; |
b7f9a11a | 613 | sigset_t *set = sigmask_to_save(); |
050902c0 | 614 | compat_sigset_t *cset = (compat_sigset_t *) set; |
1d13024e HS |
615 | |
616 | /* Set up the stack frame */ | |
050902c0 | 617 | if (is_ia32_frame()) { |
235b8022 AV |
618 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
619 | return ia32_setup_rt_frame(usig, ksig, cset, regs); | |
455edbc4 | 620 | else |
235b8022 | 621 | return ia32_setup_frame(usig, ksig, cset, regs); |
050902c0 | 622 | } else if (is_x32_frame()) { |
235b8022 | 623 | return x32_setup_rt_frame(ksig, cset, regs); |
c5a37394 | 624 | } else { |
235b8022 | 625 | return __setup_rt_frame(ksig->sig, ksig, set, regs); |
c5a37394 | 626 | } |
1d13024e HS |
627 | } |
628 | ||
a610d6e6 | 629 | static void |
235b8022 | 630 | handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
1da177e4 | 631 | { |
fd0f86b6 | 632 | bool stepping, failed; |
c5bedc68 | 633 | struct fpu *fpu = ¤t->thread.fpu; |
fd0f86b6 | 634 | |
5ed92a8a BG |
635 | if (v8086_mode(regs)) |
636 | save_v86_state((struct kernel_vm86_regs *) regs, VM86_SIGNAL); | |
637 | ||
1da177e4 | 638 | /* Are we from a system call? */ |
bb57925f | 639 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 640 | /* If so, check system call restarting.. */ |
bb57925f | 641 | switch (syscall_get_error(current, regs)) { |
ac66f3fd HH |
642 | case -ERESTART_RESTARTBLOCK: |
643 | case -ERESTARTNOHAND: | |
644 | regs->ax = -EINTR; | |
645 | break; | |
646 | ||
647 | case -ERESTARTSYS: | |
235b8022 | 648 | if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
65ea5b03 | 649 | regs->ax = -EINTR; |
1da177e4 | 650 | break; |
ac66f3fd HH |
651 | } |
652 | /* fallthrough */ | |
653 | case -ERESTARTNOINTR: | |
654 | regs->ax = regs->orig_ax; | |
655 | regs->ip -= 2; | |
656 | break; | |
1da177e4 LT |
657 | } |
658 | } | |
659 | ||
660 | /* | |
fd0f86b6 ON |
661 | * If TF is set due to a debugger (TIF_FORCED_TF), clear TF now |
662 | * so that register information in the sigcontext is correct and | |
663 | * then notify the tracer before entering the signal handler. | |
1da177e4 | 664 | */ |
fd0f86b6 ON |
665 | stepping = test_thread_flag(TIF_SINGLESTEP); |
666 | if (stepping) | |
667 | user_disable_single_step(current); | |
1da177e4 | 668 | |
235b8022 AV |
669 | failed = (setup_rt_frame(ksig, regs) < 0); |
670 | if (!failed) { | |
671 | /* | |
672 | * Clear the direction flag as per the ABI for function entry. | |
ddd40da4 | 673 | * |
24cda109 JO |
674 | * Clear RF when entering the signal handler, because |
675 | * it might disable possible debug exception from the | |
676 | * signal handler. | |
ddd40da4 | 677 | * |
fd0f86b6 ON |
678 | * Clear TF for the case when it wasn't set by debugger to |
679 | * avoid the recursive send_sigtrap() in SIGTRAP handler. | |
235b8022 | 680 | */ |
ddd40da4 | 681 | regs->flags &= ~(X86_EFLAGS_DF|X86_EFLAGS_RF|X86_EFLAGS_TF); |
66463db4 ON |
682 | /* |
683 | * Ensure the signal handler starts with the new fpu state. | |
684 | */ | |
c5bedc68 | 685 | if (fpu->fpstate_active) |
fbce7782 | 686 | fpu__clear(fpu); |
a610d6e6 | 687 | } |
fd0f86b6 | 688 | signal_setup_done(failed, ksig, stepping); |
1da177e4 LT |
689 | } |
690 | ||
57917752 | 691 | #ifdef CONFIG_X86_32 |
8fcd8e20 | 692 | #define NR_restart_syscall __NR_restart_syscall |
57917752 HS |
693 | #else /* !CONFIG_X86_32 */ |
694 | #define NR_restart_syscall \ | |
695 | test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall | |
696 | #endif /* CONFIG_X86_32 */ | |
697 | ||
1da177e4 LT |
698 | /* |
699 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
700 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
701 | * mistake. | |
702 | */ | |
1f484aa6 | 703 | void do_signal(struct pt_regs *regs) |
1da177e4 | 704 | { |
235b8022 | 705 | struct ksignal ksig; |
1da177e4 | 706 | |
235b8022 | 707 | if (get_signal(&ksig)) { |
7e907f48 | 708 | /* Whee! Actually deliver the signal. */ |
235b8022 | 709 | handle_signal(&ksig, regs); |
283828f3 | 710 | return; |
1da177e4 LT |
711 | } |
712 | ||
1da177e4 | 713 | /* Did we come from a system call? */ |
bb57925f | 714 | if (syscall_get_nr(current, regs) >= 0) { |
1da177e4 | 715 | /* Restart the system call - no handlers present */ |
bb57925f | 716 | switch (syscall_get_error(current, regs)) { |
283828f3 DH |
717 | case -ERESTARTNOHAND: |
718 | case -ERESTARTSYS: | |
719 | case -ERESTARTNOINTR: | |
65ea5b03 PA |
720 | regs->ax = regs->orig_ax; |
721 | regs->ip -= 2; | |
283828f3 DH |
722 | break; |
723 | ||
724 | case -ERESTART_RESTARTBLOCK: | |
8fcd8e20 | 725 | regs->ax = NR_restart_syscall; |
65ea5b03 | 726 | regs->ip -= 2; |
283828f3 | 727 | break; |
1da177e4 LT |
728 | } |
729 | } | |
283828f3 | 730 | |
ac66f3fd HH |
731 | /* |
732 | * If there's no signal to deliver, we just put the saved sigmask | |
733 | * back. | |
734 | */ | |
51a7b448 | 735 | restore_saved_sigmask(); |
1da177e4 LT |
736 | } |
737 | ||
72fa50f4 HS |
738 | void signal_fault(struct pt_regs *regs, void __user *frame, char *where) |
739 | { | |
740 | struct task_struct *me = current; | |
741 | ||
742 | if (show_unhandled_signals && printk_ratelimit()) { | |
ae417bb4 | 743 | printk("%s" |
72fa50f4 | 744 | "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx", |
ae417bb4 | 745 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
72fa50f4 HS |
746 | me->comm, me->pid, where, frame, |
747 | regs->ip, regs->sp, regs->orig_ax); | |
748 | print_vma_addr(" in ", regs->ip); | |
c767a54b | 749 | pr_cont("\n"); |
72fa50f4 HS |
750 | } |
751 | ||
752 | force_sig(SIGSEGV, me); | |
753 | } | |
c5a37394 PA |
754 | |
755 | #ifdef CONFIG_X86_X32_ABI | |
3fe26fa3 | 756 | asmlinkage long sys32_x32_rt_sigreturn(void) |
c5a37394 | 757 | { |
3fe26fa3 | 758 | struct pt_regs *regs = current_pt_regs(); |
c5a37394 PA |
759 | struct rt_sigframe_x32 __user *frame; |
760 | sigset_t set; | |
c5a37394 PA |
761 | |
762 | frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8); | |
763 | ||
764 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
765 | goto badframe; | |
766 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
767 | goto badframe; | |
768 | ||
c5a37394 PA |
769 | set_current_blocked(&set); |
770 | ||
6a3713f0 | 771 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) |
c5a37394 PA |
772 | goto badframe; |
773 | ||
90268439 | 774 | if (compat_restore_altstack(&frame->uc.uc_stack)) |
c5a37394 PA |
775 | goto badframe; |
776 | ||
6a3713f0 | 777 | return regs->ax; |
c5a37394 PA |
778 | |
779 | badframe: | |
780 | signal_fault(regs, frame, "x32 rt_sigreturn"); | |
781 | return 0; | |
782 | } | |
783 | #endif |