| 1 | /* |
| 2 | * This file is subject to the terms and conditions of the GNU General Public |
| 3 | * License. See the file "COPYING" in the main directory of this archive |
| 4 | * for more details. |
| 5 | * |
| 6 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 7 | * Copyright (C) 1994 - 2000 Ralf Baechle |
| 8 | * Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
| 9 | * Copyright (C) 2014, Imagination Technologies Ltd. |
| 10 | */ |
| 11 | #include <linux/cache.h> |
| 12 | #include <linux/context_tracking.h> |
| 13 | #include <linux/irqflags.h> |
| 14 | #include <linux/sched.h> |
| 15 | #include <linux/mm.h> |
| 16 | #include <linux/personality.h> |
| 17 | #include <linux/smp.h> |
| 18 | #include <linux/kernel.h> |
| 19 | #include <linux/signal.h> |
| 20 | #include <linux/errno.h> |
| 21 | #include <linux/wait.h> |
| 22 | #include <linux/ptrace.h> |
| 23 | #include <linux/unistd.h> |
| 24 | #include <linux/uprobes.h> |
| 25 | #include <linux/compiler.h> |
| 26 | #include <linux/syscalls.h> |
| 27 | #include <linux/uaccess.h> |
| 28 | #include <linux/tracehook.h> |
| 29 | |
| 30 | #include <asm/abi.h> |
| 31 | #include <asm/asm.h> |
| 32 | #include <linux/bitops.h> |
| 33 | #include <asm/cacheflush.h> |
| 34 | #include <asm/fpu.h> |
| 35 | #include <asm/sim.h> |
| 36 | #include <asm/ucontext.h> |
| 37 | #include <asm/cpu-features.h> |
| 38 | #include <asm/war.h> |
| 39 | #include <asm/dsp.h> |
| 40 | #include <asm/inst.h> |
| 41 | #include <asm/msa.h> |
| 42 | |
| 43 | #include "signal-common.h" |
| 44 | |
| 45 | static int (*save_fp_context)(void __user *sc); |
| 46 | static int (*restore_fp_context)(void __user *sc); |
| 47 | |
| 48 | struct sigframe { |
| 49 | u32 sf_ass[4]; /* argument save space for o32 */ |
| 50 | u32 sf_pad[2]; /* Was: signal trampoline */ |
| 51 | |
| 52 | /* Matches struct ucontext from its uc_mcontext field onwards */ |
| 53 | struct sigcontext sf_sc; |
| 54 | sigset_t sf_mask; |
| 55 | unsigned long long sf_extcontext[0]; |
| 56 | }; |
| 57 | |
| 58 | struct rt_sigframe { |
| 59 | u32 rs_ass[4]; /* argument save space for o32 */ |
| 60 | u32 rs_pad[2]; /* Was: signal trampoline */ |
| 61 | struct siginfo rs_info; |
| 62 | struct ucontext rs_uc; |
| 63 | }; |
| 64 | |
| 65 | /* |
| 66 | * Thread saved context copy to/from a signal context presumed to be on the |
| 67 | * user stack, and therefore accessed with appropriate macros from uaccess.h. |
| 68 | */ |
| 69 | static int copy_fp_to_sigcontext(void __user *sc) |
| 70 | { |
| 71 | struct mips_abi *abi = current->thread.abi; |
| 72 | uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| 73 | uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| 74 | int i; |
| 75 | int err = 0; |
| 76 | int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1; |
| 77 | |
| 78 | for (i = 0; i < NUM_FPU_REGS; i += inc) { |
| 79 | err |= |
| 80 | __put_user(get_fpr64(¤t->thread.fpu.fpr[i], 0), |
| 81 | &fpregs[i]); |
| 82 | } |
| 83 | err |= __put_user(current->thread.fpu.fcr31, csr); |
| 84 | |
| 85 | return err; |
| 86 | } |
| 87 | |
| 88 | static int copy_fp_from_sigcontext(void __user *sc) |
| 89 | { |
| 90 | struct mips_abi *abi = current->thread.abi; |
| 91 | uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| 92 | uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| 93 | int i; |
| 94 | int err = 0; |
| 95 | int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1; |
| 96 | u64 fpr_val; |
| 97 | |
| 98 | for (i = 0; i < NUM_FPU_REGS; i += inc) { |
| 99 | err |= __get_user(fpr_val, &fpregs[i]); |
| 100 | set_fpr64(¤t->thread.fpu.fpr[i], 0, fpr_val); |
| 101 | } |
| 102 | err |= __get_user(current->thread.fpu.fcr31, csr); |
| 103 | |
| 104 | return err; |
| 105 | } |
| 106 | |
| 107 | /* |
| 108 | * Wrappers for the assembly _{save,restore}_fp_context functions. |
| 109 | */ |
| 110 | static int save_hw_fp_context(void __user *sc) |
| 111 | { |
| 112 | struct mips_abi *abi = current->thread.abi; |
| 113 | uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| 114 | uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| 115 | |
| 116 | return _save_fp_context(fpregs, csr); |
| 117 | } |
| 118 | |
| 119 | static int restore_hw_fp_context(void __user *sc) |
| 120 | { |
| 121 | struct mips_abi *abi = current->thread.abi; |
| 122 | uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| 123 | uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| 124 | |
| 125 | return _restore_fp_context(fpregs, csr); |
| 126 | } |
| 127 | |
| 128 | /* |
| 129 | * Extended context handling. |
| 130 | */ |
| 131 | |
| 132 | static inline void __user *sc_to_extcontext(void __user *sc) |
| 133 | { |
| 134 | struct ucontext __user *uc; |
| 135 | |
| 136 | /* |
| 137 | * We can just pretend the sigcontext is always embedded in a struct |
| 138 | * ucontext here, because the offset from sigcontext to extended |
| 139 | * context is the same in the struct sigframe case. |
| 140 | */ |
| 141 | uc = container_of(sc, struct ucontext, uc_mcontext); |
| 142 | return &uc->uc_extcontext; |
| 143 | } |
| 144 | |
| 145 | static int save_msa_extcontext(void __user *buf) |
| 146 | { |
| 147 | struct msa_extcontext __user *msa = buf; |
| 148 | uint64_t val; |
| 149 | int i, err; |
| 150 | |
| 151 | if (!thread_msa_context_live()) |
| 152 | return 0; |
| 153 | |
| 154 | /* |
| 155 | * Ensure that we can't lose the live MSA context between checking |
| 156 | * for it & writing it to memory. |
| 157 | */ |
| 158 | preempt_disable(); |
| 159 | |
| 160 | if (is_msa_enabled()) { |
| 161 | /* |
| 162 | * There are no EVA versions of the vector register load/store |
| 163 | * instructions, so MSA context has to be saved to kernel memory |
| 164 | * and then copied to user memory. The save to kernel memory |
| 165 | * should already have been done when handling scalar FP |
| 166 | * context. |
| 167 | */ |
| 168 | BUG_ON(IS_ENABLED(CONFIG_EVA)); |
| 169 | |
| 170 | err = __put_user(read_msa_csr(), &msa->csr); |
| 171 | err |= _save_msa_all_upper(&msa->wr); |
| 172 | |
| 173 | preempt_enable(); |
| 174 | } else { |
| 175 | preempt_enable(); |
| 176 | |
| 177 | err = __put_user(current->thread.fpu.msacsr, &msa->csr); |
| 178 | |
| 179 | for (i = 0; i < NUM_FPU_REGS; i++) { |
| 180 | val = get_fpr64(¤t->thread.fpu.fpr[i], 1); |
| 181 | err |= __put_user(val, &msa->wr[i]); |
| 182 | } |
| 183 | } |
| 184 | |
| 185 | err |= __put_user(MSA_EXTCONTEXT_MAGIC, &msa->ext.magic); |
| 186 | err |= __put_user(sizeof(*msa), &msa->ext.size); |
| 187 | |
| 188 | return err ? -EFAULT : sizeof(*msa); |
| 189 | } |
| 190 | |
| 191 | static int restore_msa_extcontext(void __user *buf, unsigned int size) |
| 192 | { |
| 193 | struct msa_extcontext __user *msa = buf; |
| 194 | unsigned long long val; |
| 195 | unsigned int csr; |
| 196 | int i, err; |
| 197 | |
| 198 | if (!IS_ENABLED(CONFIG_CPU_HAS_MSA)) |
| 199 | return SIGSYS; |
| 200 | |
| 201 | if (size != sizeof(*msa)) |
| 202 | return -EINVAL; |
| 203 | |
| 204 | err = get_user(csr, &msa->csr); |
| 205 | if (err) |
| 206 | return err; |
| 207 | |
| 208 | preempt_disable(); |
| 209 | |
| 210 | if (is_msa_enabled()) { |
| 211 | /* |
| 212 | * There are no EVA versions of the vector register load/store |
| 213 | * instructions, so MSA context has to be copied to kernel |
| 214 | * memory and later loaded to registers. The same is true of |
| 215 | * scalar FP context, so FPU & MSA should have already been |
| 216 | * disabled whilst handling scalar FP context. |
| 217 | */ |
| 218 | BUG_ON(IS_ENABLED(CONFIG_EVA)); |
| 219 | |
| 220 | write_msa_csr(csr); |
| 221 | err |= _restore_msa_all_upper(&msa->wr); |
| 222 | preempt_enable(); |
| 223 | } else { |
| 224 | preempt_enable(); |
| 225 | |
| 226 | current->thread.fpu.msacsr = csr; |
| 227 | |
| 228 | for (i = 0; i < NUM_FPU_REGS; i++) { |
| 229 | err |= __get_user(val, &msa->wr[i]); |
| 230 | set_fpr64(¤t->thread.fpu.fpr[i], 1, val); |
| 231 | } |
| 232 | } |
| 233 | |
| 234 | return err; |
| 235 | } |
| 236 | |
| 237 | static int save_extcontext(void __user *buf) |
| 238 | { |
| 239 | int sz; |
| 240 | |
| 241 | sz = save_msa_extcontext(buf); |
| 242 | if (sz < 0) |
| 243 | return sz; |
| 244 | buf += sz; |
| 245 | |
| 246 | /* If no context was saved then trivially return */ |
| 247 | if (!sz) |
| 248 | return 0; |
| 249 | |
| 250 | /* Write the end marker */ |
| 251 | if (__put_user(END_EXTCONTEXT_MAGIC, (u32 *)buf)) |
| 252 | return -EFAULT; |
| 253 | |
| 254 | sz += sizeof(((struct extcontext *)NULL)->magic); |
| 255 | return sz; |
| 256 | } |
| 257 | |
| 258 | static int restore_extcontext(void __user *buf) |
| 259 | { |
| 260 | struct extcontext ext; |
| 261 | int err; |
| 262 | |
| 263 | while (1) { |
| 264 | err = __get_user(ext.magic, (unsigned int *)buf); |
| 265 | if (err) |
| 266 | return err; |
| 267 | |
| 268 | if (ext.magic == END_EXTCONTEXT_MAGIC) |
| 269 | return 0; |
| 270 | |
| 271 | err = __get_user(ext.size, (unsigned int *)(buf |
| 272 | + offsetof(struct extcontext, size))); |
| 273 | if (err) |
| 274 | return err; |
| 275 | |
| 276 | switch (ext.magic) { |
| 277 | case MSA_EXTCONTEXT_MAGIC: |
| 278 | err = restore_msa_extcontext(buf, ext.size); |
| 279 | break; |
| 280 | |
| 281 | default: |
| 282 | err = -EINVAL; |
| 283 | break; |
| 284 | } |
| 285 | |
| 286 | if (err) |
| 287 | return err; |
| 288 | |
| 289 | buf += ext.size; |
| 290 | } |
| 291 | } |
| 292 | |
| 293 | /* |
| 294 | * Helper routines |
| 295 | */ |
| 296 | int protected_save_fp_context(void __user *sc) |
| 297 | { |
| 298 | struct mips_abi *abi = current->thread.abi; |
| 299 | uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| 300 | uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| 301 | uint32_t __user *used_math = sc + abi->off_sc_used_math; |
| 302 | unsigned int used, ext_sz; |
| 303 | int err; |
| 304 | |
| 305 | used = used_math() ? USED_FP : 0; |
| 306 | if (!used) |
| 307 | goto fp_done; |
| 308 | |
| 309 | if (!test_thread_flag(TIF_32BIT_FPREGS)) |
| 310 | used |= USED_FR1; |
| 311 | if (test_thread_flag(TIF_HYBRID_FPREGS)) |
| 312 | used |= USED_HYBRID_FPRS; |
| 313 | |
| 314 | /* |
| 315 | * EVA does not have userland equivalents of ldc1 or sdc1, so |
| 316 | * save to the kernel FP context & copy that to userland below. |
| 317 | */ |
| 318 | if (IS_ENABLED(CONFIG_EVA)) |
| 319 | lose_fpu(1); |
| 320 | |
| 321 | while (1) { |
| 322 | lock_fpu_owner(); |
| 323 | if (is_fpu_owner()) { |
| 324 | err = save_fp_context(sc); |
| 325 | unlock_fpu_owner(); |
| 326 | } else { |
| 327 | unlock_fpu_owner(); |
| 328 | err = copy_fp_to_sigcontext(sc); |
| 329 | } |
| 330 | if (likely(!err)) |
| 331 | break; |
| 332 | /* touch the sigcontext and try again */ |
| 333 | err = __put_user(0, &fpregs[0]) | |
| 334 | __put_user(0, &fpregs[31]) | |
| 335 | __put_user(0, csr); |
| 336 | if (err) |
| 337 | return err; /* really bad sigcontext */ |
| 338 | } |
| 339 | |
| 340 | fp_done: |
| 341 | ext_sz = err = save_extcontext(sc_to_extcontext(sc)); |
| 342 | if (err < 0) |
| 343 | return err; |
| 344 | used |= ext_sz ? USED_EXTCONTEXT : 0; |
| 345 | |
| 346 | return __put_user(used, used_math); |
| 347 | } |
| 348 | |
| 349 | int protected_restore_fp_context(void __user *sc) |
| 350 | { |
| 351 | struct mips_abi *abi = current->thread.abi; |
| 352 | uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
| 353 | uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
| 354 | uint32_t __user *used_math = sc + abi->off_sc_used_math; |
| 355 | unsigned int used; |
| 356 | int err, sig = 0, tmp __maybe_unused; |
| 357 | |
| 358 | err = __get_user(used, used_math); |
| 359 | conditional_used_math(used & USED_FP); |
| 360 | |
| 361 | /* |
| 362 | * The signal handler may have used FPU; give it up if the program |
| 363 | * doesn't want it following sigreturn. |
| 364 | */ |
| 365 | if (err || !(used & USED_FP)) |
| 366 | lose_fpu(0); |
| 367 | if (err) |
| 368 | return err; |
| 369 | if (!(used & USED_FP)) |
| 370 | goto fp_done; |
| 371 | |
| 372 | err = sig = fpcsr_pending(csr); |
| 373 | if (err < 0) |
| 374 | return err; |
| 375 | |
| 376 | /* |
| 377 | * EVA does not have userland equivalents of ldc1 or sdc1, so we |
| 378 | * disable the FPU here such that the code below simply copies to |
| 379 | * the kernel FP context. |
| 380 | */ |
| 381 | if (IS_ENABLED(CONFIG_EVA)) |
| 382 | lose_fpu(0); |
| 383 | |
| 384 | while (1) { |
| 385 | lock_fpu_owner(); |
| 386 | if (is_fpu_owner()) { |
| 387 | err = restore_fp_context(sc); |
| 388 | unlock_fpu_owner(); |
| 389 | } else { |
| 390 | unlock_fpu_owner(); |
| 391 | err = copy_fp_from_sigcontext(sc); |
| 392 | } |
| 393 | if (likely(!err)) |
| 394 | break; |
| 395 | /* touch the sigcontext and try again */ |
| 396 | err = __get_user(tmp, &fpregs[0]) | |
| 397 | __get_user(tmp, &fpregs[31]) | |
| 398 | __get_user(tmp, csr); |
| 399 | if (err) |
| 400 | break; /* really bad sigcontext */ |
| 401 | } |
| 402 | |
| 403 | fp_done: |
| 404 | if (!err && (used & USED_EXTCONTEXT)) |
| 405 | err = restore_extcontext(sc_to_extcontext(sc)); |
| 406 | |
| 407 | return err ?: sig; |
| 408 | } |
| 409 | |
| 410 | int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) |
| 411 | { |
| 412 | int err = 0; |
| 413 | int i; |
| 414 | |
| 415 | err |= __put_user(regs->cp0_epc, &sc->sc_pc); |
| 416 | |
| 417 | err |= __put_user(0, &sc->sc_regs[0]); |
| 418 | for (i = 1; i < 32; i++) |
| 419 | err |= __put_user(regs->regs[i], &sc->sc_regs[i]); |
| 420 | |
| 421 | #ifdef CONFIG_CPU_HAS_SMARTMIPS |
| 422 | err |= __put_user(regs->acx, &sc->sc_acx); |
| 423 | #endif |
| 424 | err |= __put_user(regs->hi, &sc->sc_mdhi); |
| 425 | err |= __put_user(regs->lo, &sc->sc_mdlo); |
| 426 | if (cpu_has_dsp) { |
| 427 | err |= __put_user(mfhi1(), &sc->sc_hi1); |
| 428 | err |= __put_user(mflo1(), &sc->sc_lo1); |
| 429 | err |= __put_user(mfhi2(), &sc->sc_hi2); |
| 430 | err |= __put_user(mflo2(), &sc->sc_lo2); |
| 431 | err |= __put_user(mfhi3(), &sc->sc_hi3); |
| 432 | err |= __put_user(mflo3(), &sc->sc_lo3); |
| 433 | err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp); |
| 434 | } |
| 435 | |
| 436 | |
| 437 | /* |
| 438 | * Save FPU state to signal context. Signal handler |
| 439 | * will "inherit" current FPU state. |
| 440 | */ |
| 441 | err |= protected_save_fp_context(sc); |
| 442 | |
| 443 | return err; |
| 444 | } |
| 445 | |
| 446 | static size_t extcontext_max_size(void) |
| 447 | { |
| 448 | size_t sz = 0; |
| 449 | |
| 450 | /* |
| 451 | * The assumption here is that between this point & the point at which |
| 452 | * the extended context is saved the size of the context should only |
| 453 | * ever be able to shrink (if the task is preempted), but never grow. |
| 454 | * That is, what this function returns is an upper bound on the size of |
| 455 | * the extended context for the current task at the current time. |
| 456 | */ |
| 457 | |
| 458 | if (thread_msa_context_live()) |
| 459 | sz += sizeof(struct msa_extcontext); |
| 460 | |
| 461 | /* If any context is saved then we'll append the end marker */ |
| 462 | if (sz) |
| 463 | sz += sizeof(((struct extcontext *)NULL)->magic); |
| 464 | |
| 465 | return sz; |
| 466 | } |
| 467 | |
| 468 | int fpcsr_pending(unsigned int __user *fpcsr) |
| 469 | { |
| 470 | int err, sig = 0; |
| 471 | unsigned int csr, enabled; |
| 472 | |
| 473 | err = __get_user(csr, fpcsr); |
| 474 | enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5); |
| 475 | /* |
| 476 | * If the signal handler set some FPU exceptions, clear it and |
| 477 | * send SIGFPE. |
| 478 | */ |
| 479 | if (csr & enabled) { |
| 480 | csr &= ~enabled; |
| 481 | err |= __put_user(csr, fpcsr); |
| 482 | sig = SIGFPE; |
| 483 | } |
| 484 | return err ?: sig; |
| 485 | } |
| 486 | |
| 487 | int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) |
| 488 | { |
| 489 | unsigned long treg; |
| 490 | int err = 0; |
| 491 | int i; |
| 492 | |
| 493 | /* Always make any pending restarted system calls return -EINTR */ |
| 494 | current->restart_block.fn = do_no_restart_syscall; |
| 495 | |
| 496 | err |= __get_user(regs->cp0_epc, &sc->sc_pc); |
| 497 | |
| 498 | #ifdef CONFIG_CPU_HAS_SMARTMIPS |
| 499 | err |= __get_user(regs->acx, &sc->sc_acx); |
| 500 | #endif |
| 501 | err |= __get_user(regs->hi, &sc->sc_mdhi); |
| 502 | err |= __get_user(regs->lo, &sc->sc_mdlo); |
| 503 | if (cpu_has_dsp) { |
| 504 | err |= __get_user(treg, &sc->sc_hi1); mthi1(treg); |
| 505 | err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg); |
| 506 | err |= __get_user(treg, &sc->sc_hi2); mthi2(treg); |
| 507 | err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg); |
| 508 | err |= __get_user(treg, &sc->sc_hi3); mthi3(treg); |
| 509 | err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg); |
| 510 | err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK); |
| 511 | } |
| 512 | |
| 513 | for (i = 1; i < 32; i++) |
| 514 | err |= __get_user(regs->regs[i], &sc->sc_regs[i]); |
| 515 | |
| 516 | return err ?: protected_restore_fp_context(sc); |
| 517 | } |
| 518 | |
| 519 | void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, |
| 520 | size_t frame_size) |
| 521 | { |
| 522 | unsigned long sp; |
| 523 | |
| 524 | /* Leave space for potential extended context */ |
| 525 | frame_size += extcontext_max_size(); |
| 526 | |
| 527 | /* Default to using normal stack */ |
| 528 | sp = regs->regs[29]; |
| 529 | |
| 530 | /* |
| 531 | * FPU emulator may have it's own trampoline active just |
| 532 | * above the user stack, 16-bytes before the next lowest |
| 533 | * 16 byte boundary. Try to avoid trashing it. |
| 534 | */ |
| 535 | sp -= 32; |
| 536 | |
| 537 | sp = sigsp(sp, ksig); |
| 538 | |
| 539 | return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK)); |
| 540 | } |
| 541 | |
| 542 | /* |
| 543 | * Atomically swap in the new signal mask, and wait for a signal. |
| 544 | */ |
| 545 | |
| 546 | #ifdef CONFIG_TRAD_SIGNALS |
| 547 | SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset) |
| 548 | { |
| 549 | return sys_rt_sigsuspend(uset, sizeof(sigset_t)); |
| 550 | } |
| 551 | #endif |
| 552 | |
| 553 | #ifdef CONFIG_TRAD_SIGNALS |
| 554 | SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act, |
| 555 | struct sigaction __user *, oact) |
| 556 | { |
| 557 | struct k_sigaction new_ka, old_ka; |
| 558 | int ret; |
| 559 | int err = 0; |
| 560 | |
| 561 | if (act) { |
| 562 | old_sigset_t mask; |
| 563 | |
| 564 | if (!access_ok(VERIFY_READ, act, sizeof(*act))) |
| 565 | return -EFAULT; |
| 566 | err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler); |
| 567 | err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags); |
| 568 | err |= __get_user(mask, &act->sa_mask.sig[0]); |
| 569 | if (err) |
| 570 | return -EFAULT; |
| 571 | |
| 572 | siginitset(&new_ka.sa.sa_mask, mask); |
| 573 | } |
| 574 | |
| 575 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); |
| 576 | |
| 577 | if (!ret && oact) { |
| 578 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact))) |
| 579 | return -EFAULT; |
| 580 | err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags); |
| 581 | err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler); |
| 582 | err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig); |
| 583 | err |= __put_user(0, &oact->sa_mask.sig[1]); |
| 584 | err |= __put_user(0, &oact->sa_mask.sig[2]); |
| 585 | err |= __put_user(0, &oact->sa_mask.sig[3]); |
| 586 | if (err) |
| 587 | return -EFAULT; |
| 588 | } |
| 589 | |
| 590 | return ret; |
| 591 | } |
| 592 | #endif |
| 593 | |
| 594 | #ifdef CONFIG_TRAD_SIGNALS |
| 595 | asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs) |
| 596 | { |
| 597 | struct sigframe __user *frame; |
| 598 | sigset_t blocked; |
| 599 | int sig; |
| 600 | |
| 601 | frame = (struct sigframe __user *) regs.regs[29]; |
| 602 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
| 603 | goto badframe; |
| 604 | if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked))) |
| 605 | goto badframe; |
| 606 | |
| 607 | set_current_blocked(&blocked); |
| 608 | |
| 609 | sig = restore_sigcontext(®s, &frame->sf_sc); |
| 610 | if (sig < 0) |
| 611 | goto badframe; |
| 612 | else if (sig) |
| 613 | force_sig(sig, current); |
| 614 | |
| 615 | /* |
| 616 | * Don't let your children do this ... |
| 617 | */ |
| 618 | __asm__ __volatile__( |
| 619 | "move\t$29, %0\n\t" |
| 620 | "j\tsyscall_exit" |
| 621 | :/* no outputs */ |
| 622 | :"r" (®s)); |
| 623 | /* Unreached */ |
| 624 | |
| 625 | badframe: |
| 626 | force_sig(SIGSEGV, current); |
| 627 | } |
| 628 | #endif /* CONFIG_TRAD_SIGNALS */ |
| 629 | |
| 630 | asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs) |
| 631 | { |
| 632 | struct rt_sigframe __user *frame; |
| 633 | sigset_t set; |
| 634 | int sig; |
| 635 | |
| 636 | frame = (struct rt_sigframe __user *) regs.regs[29]; |
| 637 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
| 638 | goto badframe; |
| 639 | if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set))) |
| 640 | goto badframe; |
| 641 | |
| 642 | set_current_blocked(&set); |
| 643 | |
| 644 | sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext); |
| 645 | if (sig < 0) |
| 646 | goto badframe; |
| 647 | else if (sig) |
| 648 | force_sig(sig, current); |
| 649 | |
| 650 | if (restore_altstack(&frame->rs_uc.uc_stack)) |
| 651 | goto badframe; |
| 652 | |
| 653 | /* |
| 654 | * Don't let your children do this ... |
| 655 | */ |
| 656 | __asm__ __volatile__( |
| 657 | "move\t$29, %0\n\t" |
| 658 | "j\tsyscall_exit" |
| 659 | :/* no outputs */ |
| 660 | :"r" (®s)); |
| 661 | /* Unreached */ |
| 662 | |
| 663 | badframe: |
| 664 | force_sig(SIGSEGV, current); |
| 665 | } |
| 666 | |
| 667 | #ifdef CONFIG_TRAD_SIGNALS |
| 668 | static int setup_frame(void *sig_return, struct ksignal *ksig, |
| 669 | struct pt_regs *regs, sigset_t *set) |
| 670 | { |
| 671 | struct sigframe __user *frame; |
| 672 | int err = 0; |
| 673 | |
| 674 | frame = get_sigframe(ksig, regs, sizeof(*frame)); |
| 675 | if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) |
| 676 | return -EFAULT; |
| 677 | |
| 678 | err |= setup_sigcontext(regs, &frame->sf_sc); |
| 679 | err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set)); |
| 680 | if (err) |
| 681 | return -EFAULT; |
| 682 | |
| 683 | /* |
| 684 | * Arguments to signal handler: |
| 685 | * |
| 686 | * a0 = signal number |
| 687 | * a1 = 0 (should be cause) |
| 688 | * a2 = pointer to struct sigcontext |
| 689 | * |
| 690 | * $25 and c0_epc point to the signal handler, $29 points to the |
| 691 | * struct sigframe. |
| 692 | */ |
| 693 | regs->regs[ 4] = ksig->sig; |
| 694 | regs->regs[ 5] = 0; |
| 695 | regs->regs[ 6] = (unsigned long) &frame->sf_sc; |
| 696 | regs->regs[29] = (unsigned long) frame; |
| 697 | regs->regs[31] = (unsigned long) sig_return; |
| 698 | regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; |
| 699 | |
| 700 | DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", |
| 701 | current->comm, current->pid, |
| 702 | frame, regs->cp0_epc, regs->regs[31]); |
| 703 | return 0; |
| 704 | } |
| 705 | #endif |
| 706 | |
| 707 | static int setup_rt_frame(void *sig_return, struct ksignal *ksig, |
| 708 | struct pt_regs *regs, sigset_t *set) |
| 709 | { |
| 710 | struct rt_sigframe __user *frame; |
| 711 | int err = 0; |
| 712 | |
| 713 | frame = get_sigframe(ksig, regs, sizeof(*frame)); |
| 714 | if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) |
| 715 | return -EFAULT; |
| 716 | |
| 717 | /* Create siginfo. */ |
| 718 | err |= copy_siginfo_to_user(&frame->rs_info, &ksig->info); |
| 719 | |
| 720 | /* Create the ucontext. */ |
| 721 | err |= __put_user(0, &frame->rs_uc.uc_flags); |
| 722 | err |= __put_user(NULL, &frame->rs_uc.uc_link); |
| 723 | err |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]); |
| 724 | err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext); |
| 725 | err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set)); |
| 726 | |
| 727 | if (err) |
| 728 | return -EFAULT; |
| 729 | |
| 730 | /* |
| 731 | * Arguments to signal handler: |
| 732 | * |
| 733 | * a0 = signal number |
| 734 | * a1 = 0 (should be cause) |
| 735 | * a2 = pointer to ucontext |
| 736 | * |
| 737 | * $25 and c0_epc point to the signal handler, $29 points to |
| 738 | * the struct rt_sigframe. |
| 739 | */ |
| 740 | regs->regs[ 4] = ksig->sig; |
| 741 | regs->regs[ 5] = (unsigned long) &frame->rs_info; |
| 742 | regs->regs[ 6] = (unsigned long) &frame->rs_uc; |
| 743 | regs->regs[29] = (unsigned long) frame; |
| 744 | regs->regs[31] = (unsigned long) sig_return; |
| 745 | regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; |
| 746 | |
| 747 | DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", |
| 748 | current->comm, current->pid, |
| 749 | frame, regs->cp0_epc, regs->regs[31]); |
| 750 | |
| 751 | return 0; |
| 752 | } |
| 753 | |
| 754 | struct mips_abi mips_abi = { |
| 755 | #ifdef CONFIG_TRAD_SIGNALS |
| 756 | .setup_frame = setup_frame, |
| 757 | #endif |
| 758 | .setup_rt_frame = setup_rt_frame, |
| 759 | .restart = __NR_restart_syscall, |
| 760 | |
| 761 | .off_sc_fpregs = offsetof(struct sigcontext, sc_fpregs), |
| 762 | .off_sc_fpc_csr = offsetof(struct sigcontext, sc_fpc_csr), |
| 763 | .off_sc_used_math = offsetof(struct sigcontext, sc_used_math), |
| 764 | |
| 765 | .vdso = &vdso_image, |
| 766 | }; |
| 767 | |
| 768 | static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
| 769 | { |
| 770 | sigset_t *oldset = sigmask_to_save(); |
| 771 | int ret; |
| 772 | struct mips_abi *abi = current->thread.abi; |
| 773 | void *vdso = current->mm->context.vdso; |
| 774 | |
| 775 | if (regs->regs[0]) { |
| 776 | switch(regs->regs[2]) { |
| 777 | case ERESTART_RESTARTBLOCK: |
| 778 | case ERESTARTNOHAND: |
| 779 | regs->regs[2] = EINTR; |
| 780 | break; |
| 781 | case ERESTARTSYS: |
| 782 | if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
| 783 | regs->regs[2] = EINTR; |
| 784 | break; |
| 785 | } |
| 786 | /* fallthrough */ |
| 787 | case ERESTARTNOINTR: |
| 788 | regs->regs[7] = regs->regs[26]; |
| 789 | regs->regs[2] = regs->regs[0]; |
| 790 | regs->cp0_epc -= 4; |
| 791 | } |
| 792 | |
| 793 | regs->regs[0] = 0; /* Don't deal with this again. */ |
| 794 | } |
| 795 | |
| 796 | if (sig_uses_siginfo(&ksig->ka, abi)) |
| 797 | ret = abi->setup_rt_frame(vdso + abi->vdso->off_rt_sigreturn, |
| 798 | ksig, regs, oldset); |
| 799 | else |
| 800 | ret = abi->setup_frame(vdso + abi->vdso->off_sigreturn, |
| 801 | ksig, regs, oldset); |
| 802 | |
| 803 | signal_setup_done(ret, ksig, 0); |
| 804 | } |
| 805 | |
| 806 | static void do_signal(struct pt_regs *regs) |
| 807 | { |
| 808 | struct ksignal ksig; |
| 809 | |
| 810 | if (get_signal(&ksig)) { |
| 811 | /* Whee! Actually deliver the signal. */ |
| 812 | handle_signal(&ksig, regs); |
| 813 | return; |
| 814 | } |
| 815 | |
| 816 | if (regs->regs[0]) { |
| 817 | switch (regs->regs[2]) { |
| 818 | case ERESTARTNOHAND: |
| 819 | case ERESTARTSYS: |
| 820 | case ERESTARTNOINTR: |
| 821 | regs->regs[2] = regs->regs[0]; |
| 822 | regs->regs[7] = regs->regs[26]; |
| 823 | regs->cp0_epc -= 4; |
| 824 | break; |
| 825 | |
| 826 | case ERESTART_RESTARTBLOCK: |
| 827 | regs->regs[2] = current->thread.abi->restart; |
| 828 | regs->regs[7] = regs->regs[26]; |
| 829 | regs->cp0_epc -= 4; |
| 830 | break; |
| 831 | } |
| 832 | regs->regs[0] = 0; /* Don't deal with this again. */ |
| 833 | } |
| 834 | |
| 835 | /* |
| 836 | * If there's no signal to deliver, we just put the saved sigmask |
| 837 | * back |
| 838 | */ |
| 839 | restore_saved_sigmask(); |
| 840 | } |
| 841 | |
| 842 | /* |
| 843 | * notification of userspace execution resumption |
| 844 | * - triggered by the TIF_WORK_MASK flags |
| 845 | */ |
| 846 | asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused, |
| 847 | __u32 thread_info_flags) |
| 848 | { |
| 849 | local_irq_enable(); |
| 850 | |
| 851 | user_exit(); |
| 852 | |
| 853 | if (thread_info_flags & _TIF_UPROBE) |
| 854 | uprobe_notify_resume(regs); |
| 855 | |
| 856 | /* deal with pending signal delivery */ |
| 857 | if (thread_info_flags & _TIF_SIGPENDING) |
| 858 | do_signal(regs); |
| 859 | |
| 860 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { |
| 861 | clear_thread_flag(TIF_NOTIFY_RESUME); |
| 862 | tracehook_notify_resume(regs); |
| 863 | } |
| 864 | |
| 865 | user_enter(); |
| 866 | } |
| 867 | |
| 868 | #ifdef CONFIG_SMP |
| 869 | static int smp_save_fp_context(void __user *sc) |
| 870 | { |
| 871 | return raw_cpu_has_fpu |
| 872 | ? save_hw_fp_context(sc) |
| 873 | : copy_fp_to_sigcontext(sc); |
| 874 | } |
| 875 | |
| 876 | static int smp_restore_fp_context(void __user *sc) |
| 877 | { |
| 878 | return raw_cpu_has_fpu |
| 879 | ? restore_hw_fp_context(sc) |
| 880 | : copy_fp_from_sigcontext(sc); |
| 881 | } |
| 882 | #endif |
| 883 | |
| 884 | static int signal_setup(void) |
| 885 | { |
| 886 | /* |
| 887 | * The offset from sigcontext to extended context should be the same |
| 888 | * regardless of the type of signal, such that userland can always know |
| 889 | * where to look if it wishes to find the extended context structures. |
| 890 | */ |
| 891 | BUILD_BUG_ON((offsetof(struct sigframe, sf_extcontext) - |
| 892 | offsetof(struct sigframe, sf_sc)) != |
| 893 | (offsetof(struct rt_sigframe, rs_uc.uc_extcontext) - |
| 894 | offsetof(struct rt_sigframe, rs_uc.uc_mcontext))); |
| 895 | |
| 896 | #ifdef CONFIG_SMP |
| 897 | /* For now just do the cpu_has_fpu check when the functions are invoked */ |
| 898 | save_fp_context = smp_save_fp_context; |
| 899 | restore_fp_context = smp_restore_fp_context; |
| 900 | #else |
| 901 | if (cpu_has_fpu) { |
| 902 | save_fp_context = save_hw_fp_context; |
| 903 | restore_fp_context = restore_hw_fp_context; |
| 904 | } else { |
| 905 | save_fp_context = copy_fp_to_sigcontext; |
| 906 | restore_fp_context = copy_fp_from_sigcontext; |
| 907 | } |
| 908 | #endif /* CONFIG_SMP */ |
| 909 | |
| 910 | return 0; |
| 911 | } |
| 912 | |
| 913 | arch_initcall(signal_setup); |