arch/arm64/kernel/ptrace.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Based on arch/arm/kernel/ptrace.c
   4  *
   5  * By Ross Biro 1/23/92
   6  * edited by Linus Torvalds
   7  * ARM modifications Copyright (C) 2000 Russell King
   8  * Copyright (C) 2012 ARM Ltd.
   9  */
  10
  11 #include <linux/audit.h>
  12 #include <linux/compat.h>
  13 #include <linux/kernel.h>
  14 #include <linux/sched/signal.h>
  15 #include <linux/sched/task_stack.h>
  16 #include <linux/mm.h>
  17 #include <linux/nospec.h>
  18 #include <linux/smp.h>
  19 #include <linux/ptrace.h>
  20 #include <linux/user.h>
  21 #include <linux/seccomp.h>
  22 #include <linux/security.h>
  23 #include <linux/init.h>
  24 #include <linux/signal.h>
  25 #include <linux/string.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/perf_event.h>
  28 #include <linux/hw_breakpoint.h>
  29 #include <linux/regset.h>
  30 #include <linux/elf.h>
  31
  32 #include <asm/compat.h>
  33 #include <asm/cpufeature.h>
  34 #include <asm/debug-monitors.h>
  35 #include <asm/fpsimd.h>
  36 #include <asm/mte.h>
  37 #include <asm/pointer_auth.h>
  38 #include <asm/stacktrace.h>
  39 #include <asm/syscall.h>
  40 #include <asm/traps.h>
  41 #include <asm/system_misc.h>
  42
  43 #define CREATE_TRACE_POINTS
  44 #include <trace/events/syscalls.h>
  45
  46 struct pt_regs_offset {
  47         const char *name;
  48         int offset;
  49 };
  50
  51 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
  52 #define REG_OFFSET_END {.name = NULL, .offset = 0}
  53 #define GPR_OFFSET_NAME(r) \
  54         {.name = "x" #r, .offset = offsetof(struct pt_regs, regs[r])}
  55
  56 static const struct pt_regs_offset regoffset_table[] = {
  57         GPR_OFFSET_NAME(0),
  58         GPR_OFFSET_NAME(1),
  59         GPR_OFFSET_NAME(2),
  60         GPR_OFFSET_NAME(3),
  61         GPR_OFFSET_NAME(4),
  62         GPR_OFFSET_NAME(5),
  63         GPR_OFFSET_NAME(6),
  64         GPR_OFFSET_NAME(7),
  65         GPR_OFFSET_NAME(8),
  66         GPR_OFFSET_NAME(9),
  67         GPR_OFFSET_NAME(10),
  68         GPR_OFFSET_NAME(11),
  69         GPR_OFFSET_NAME(12),
  70         GPR_OFFSET_NAME(13),
  71         GPR_OFFSET_NAME(14),
  72         GPR_OFFSET_NAME(15),
  73         GPR_OFFSET_NAME(16),
  74         GPR_OFFSET_NAME(17),
  75         GPR_OFFSET_NAME(18),
  76         GPR_OFFSET_NAME(19),
  77         GPR_OFFSET_NAME(20),
  78         GPR_OFFSET_NAME(21),
  79         GPR_OFFSET_NAME(22),
  80         GPR_OFFSET_NAME(23),
  81         GPR_OFFSET_NAME(24),
  82         GPR_OFFSET_NAME(25),
  83         GPR_OFFSET_NAME(26),
  84         GPR_OFFSET_NAME(27),
  85         GPR_OFFSET_NAME(28),
  86         GPR_OFFSET_NAME(29),
  87         GPR_OFFSET_NAME(30),
  88         {.name = "lr", .offset = offsetof(struct pt_regs, regs[30])},
  89         REG_OFFSET_NAME(sp),
  90         REG_OFFSET_NAME(pc),
  91         REG_OFFSET_NAME(pstate),
  92         REG_OFFSET_END,
  93 };
  94
  95 /**
  96  * regs_query_register_offset() - query register offset from its name
  97  * @name:       the name of a register
  98  *
  99  * regs_query_register_offset() returns the offset of a register in struct
 100  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
 101  */
 102 int regs_query_register_offset(const char *name)
 103 {
 104         const struct pt_regs_offset *roff;
 105
 106         for (roff = regoffset_table; roff->name != NULL; roff++)
 107                 if (!strcmp(roff->name, name))
 108                         return roff->offset;
 109         return -EINVAL;
 110 }
 111
 112 /**
 113  * regs_within_kernel_stack() - check the address in the stack
 114  * @regs:      pt_regs which contains kernel stack pointer.
 115  * @addr:      address which is checked.
 116  *
 117  * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
 118  * If @addr is within the kernel stack, it returns true. If not, returns false.
 119  */
 120 static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
 121 {
 122         return ((addr & ~(THREAD_SIZE - 1))  ==
 123                 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))) ||
 124                 on_irq_stack(addr, sizeof(unsigned long));
 125 }
 126
 127 /**
 128  * regs_get_kernel_stack_nth() - get Nth entry of the stack
 129  * @regs:       pt_regs which contains kernel stack pointer.
 130  * @n:          stack entry number.
 131  *
 132  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
 133  * is specified by @regs. If the @n th entry is NOT in the kernel stack,
 134  * this returns 0.
 135  */
 136 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
 137 {
 138         unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
 139
 140         addr += n;
 141         if (regs_within_kernel_stack(regs, (unsigned long)addr))
 142                 return *addr;
 143         else
 144                 return 0;
 145 }
 146
 147 /*
 148  * TODO: does not yet catch signals sent when the child dies.
 149  * in exit.c or in signal.c.
 150  */
 151
 152 /*
 153  * Called by kernel/ptrace.c when detaching..
 154  */
 155 void ptrace_disable(struct task_struct *child)
 156 {
 157         /*
 158          * This would be better off in core code, but PTRACE_DETACH has
 159          * grown its fair share of arch-specific worts and changing it
 160          * is likely to cause regressions on obscure architectures.
 161          */
 162         user_disable_single_step(child);
 163 }
 164
 165 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 166 /*
 167  * Handle hitting a HW-breakpoint.
 168  */
 169 static void ptrace_hbptriggered(struct perf_event *bp,
 170                                 struct perf_sample_data *data,
 171                                 struct pt_regs *regs)
 172 {
 173         struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
 174         const char *desc = "Hardware breakpoint trap (ptrace)";
 175
 176 #ifdef CONFIG_COMPAT
 177         if (is_compat_task()) {
 178                 int si_errno = 0;
 179                 int i;
 180
 181                 for (i = 0; i < ARM_MAX_BRP; ++i) {
 182                         if (current->thread.debug.hbp_break[i] == bp) {
 183                                 si_errno = (i << 1) + 1;
 184                                 break;
 185                         }
 186                 }
 187
 188                 for (i = 0; i < ARM_MAX_WRP; ++i) {
 189                         if (current->thread.debug.hbp_watch[i] == bp) {
 190                                 si_errno = -((i << 1) + 1);
 191                                 break;
 192                         }
 193                 }
 194                 arm64_force_sig_ptrace_errno_trap(si_errno, bkpt->trigger,
 195                                                   desc);
 196                 return;
 197         }
 198 #endif
 199         arm64_force_sig_fault(SIGTRAP, TRAP_HWBKPT, bkpt->trigger, desc);
 200 }
 201
 202 /*
 203  * Unregister breakpoints from this task and reset the pointers in
 204  * the thread_struct.
 205  */
 206 void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
 207 {
 208         int i;
 209         struct thread_struct *t = &tsk->thread;
 210
 211         for (i = 0; i < ARM_MAX_BRP; i++) {
 212                 if (t->debug.hbp_break[i]) {
 213                         unregister_hw_breakpoint(t->debug.hbp_break[i]);
 214                         t->debug.hbp_break[i] = NULL;
 215                 }
 216         }
 217
 218         for (i = 0; i < ARM_MAX_WRP; i++) {
 219                 if (t->debug.hbp_watch[i]) {
 220                         unregister_hw_breakpoint(t->debug.hbp_watch[i]);
 221                         t->debug.hbp_watch[i] = NULL;
 222                 }
 223         }
 224 }
 225
 226 void ptrace_hw_copy_thread(struct task_struct *tsk)
 227 {
 228         memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
 229 }
 230
 231 static struct perf_event *ptrace_hbp_get_event(unsigned int note_type,
 232                                                struct task_struct *tsk,
 233                                                unsigned long idx)
 234 {
 235         struct perf_event *bp = ERR_PTR(-EINVAL);
 236
 237         switch (note_type) {
 238         case NT_ARM_HW_BREAK:
 239                 if (idx >= ARM_MAX_BRP)
 240                         goto out;
 241                 idx = array_index_nospec(idx, ARM_MAX_BRP);
 242                 bp = tsk->thread.debug.hbp_break[idx];
 243                 break;
 244         case NT_ARM_HW_WATCH:
 245                 if (idx >= ARM_MAX_WRP)
 246                         goto out;
 247                 idx = array_index_nospec(idx, ARM_MAX_WRP);
 248                 bp = tsk->thread.debug.hbp_watch[idx];
 249                 break;
 250         }
 251
 252 out:
 253         return bp;
 254 }
 255
 256 static int ptrace_hbp_set_event(unsigned int note_type,
 257                                 struct task_struct *tsk,
 258                                 unsigned long idx,
 259                                 struct perf_event *bp)
 260 {
 261         int err = -EINVAL;
 262
 263         switch (note_type) {
 264         case NT_ARM_HW_BREAK:
 265                 if (idx >= ARM_MAX_BRP)
 266                         goto out;
 267                 idx = array_index_nospec(idx, ARM_MAX_BRP);
 268                 tsk->thread.debug.hbp_break[idx] = bp;
 269                 err = 0;
 270                 break;
 271         case NT_ARM_HW_WATCH:
 272                 if (idx >= ARM_MAX_WRP)
 273                         goto out;
 274                 idx = array_index_nospec(idx, ARM_MAX_WRP);
 275                 tsk->thread.debug.hbp_watch[idx] = bp;
 276                 err = 0;
 277                 break;
 278         }
 279
 280 out:
 281         return err;
 282 }
 283
 284 static struct perf_event *ptrace_hbp_create(unsigned int note_type,
 285                                             struct task_struct *tsk,
 286                                             unsigned long idx)
 287 {
 288         struct perf_event *bp;
 289         struct perf_event_attr attr;
 290         int err, type;
 291
 292         switch (note_type) {
 293         case NT_ARM_HW_BREAK:
 294                 type = HW_BREAKPOINT_X;
 295                 break;
 296         case NT_ARM_HW_WATCH:
 297                 type = HW_BREAKPOINT_RW;
 298                 break;
 299         default:
 300                 return ERR_PTR(-EINVAL);
 301         }
 302
 303         ptrace_breakpoint_init(&attr);
 304
 305         /*
 306          * Initialise fields to sane defaults
 307          * (i.e. values that will pass validation).
 308          */
 309         attr.bp_addr    = 0;
 310         attr.bp_len     = HW_BREAKPOINT_LEN_4;
 311         attr.bp_type    = type;
 312         attr.disabled   = 1;
 313
 314         bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk);
 315         if (IS_ERR(bp))
 316                 return bp;
 317
 318         err = ptrace_hbp_set_event(note_type, tsk, idx, bp);
 319         if (err)
 320                 return ERR_PTR(err);
 321
 322         return bp;
 323 }
 324
 325 static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type,
 326                                      struct arch_hw_breakpoint_ctrl ctrl,
 327                                      struct perf_event_attr *attr)
 328 {
 329         int err, len, type, offset, disabled = !ctrl.enabled;
 330
 331         attr->disabled = disabled;
 332         if (disabled)
 333                 return 0;
 334
 335         err = arch_bp_generic_fields(ctrl, &len, &type, &offset);
 336         if (err)
 337                 return err;
 338
 339         switch (note_type) {
 340         case NT_ARM_HW_BREAK:
 341                 if ((type & HW_BREAKPOINT_X) != type)
 342                         return -EINVAL;
 343                 break;
 344         case NT_ARM_HW_WATCH:
 345                 if ((type & HW_BREAKPOINT_RW) != type)
 346                         return -EINVAL;
 347                 break;
 348         default:
 349                 return -EINVAL;
 350         }
 351
 352         attr->bp_len    = len;
 353         attr->bp_type   = type;
 354         attr->bp_addr   += offset;
 355
 356         return 0;
 357 }
 358
 359 static int ptrace_hbp_get_resource_info(unsigned int note_type, u32 *info)
 360 {
 361         u8 num;
 362         u32 reg = 0;
 363
 364         switch (note_type) {
 365         case NT_ARM_HW_BREAK:
 366                 num = hw_breakpoint_slots(TYPE_INST);
 367                 break;
 368         case NT_ARM_HW_WATCH:
 369                 num = hw_breakpoint_slots(TYPE_DATA);
 370                 break;
 371         default:
 372                 return -EINVAL;
 373         }
 374
 375         reg |= debug_monitors_arch();
 376         reg <<= 8;
 377         reg |= num;
 378
 379         *info = reg;
 380         return 0;
 381 }
 382
 383 static int ptrace_hbp_get_ctrl(unsigned int note_type,
 384                                struct task_struct *tsk,
 385                                unsigned long idx,
 386                                u32 *ctrl)
 387 {
 388         struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
 389
 390         if (IS_ERR(bp))
 391                 return PTR_ERR(bp);
 392
 393         *ctrl = bp ? encode_ctrl_reg(counter_arch_bp(bp)->ctrl) : 0;
 394         return 0;
 395 }
 396
 397 static int ptrace_hbp_get_addr(unsigned int note_type,
 398                                struct task_struct *tsk,
 399                                unsigned long idx,
 400                                u64 *addr)
 401 {
 402         struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
 403
 404         if (IS_ERR(bp))
 405                 return PTR_ERR(bp);
 406
 407         *addr = bp ? counter_arch_bp(bp)->address : 0;
 408         return 0;
 409 }
 410
 411 static struct perf_event *ptrace_hbp_get_initialised_bp(unsigned int note_type,
 412                                                         struct task_struct *tsk,
 413                                                         unsigned long idx)
 414 {
 415         struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
 416
 417         if (!bp)
 418                 bp = ptrace_hbp_create(note_type, tsk, idx);
 419
 420         return bp;
 421 }
 422
 423 static int ptrace_hbp_set_ctrl(unsigned int note_type,
 424                                struct task_struct *tsk,
 425                                unsigned long idx,
 426                                u32 uctrl)
 427 {
 428         int err;
 429         struct perf_event *bp;
 430         struct perf_event_attr attr;
 431         struct arch_hw_breakpoint_ctrl ctrl;
 432
 433         bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
 434         if (IS_ERR(bp)) {
 435                 err = PTR_ERR(bp);
 436                 return err;
 437         }
 438
 439         attr = bp->attr;
 440         decode_ctrl_reg(uctrl, &ctrl);
 441         err = ptrace_hbp_fill_attr_ctrl(note_type, ctrl, &attr);
 442         if (err)
 443                 return err;
 444
 445         return modify_user_hw_breakpoint(bp, &attr);
 446 }
 447
 448 static int ptrace_hbp_set_addr(unsigned int note_type,
 449                                struct task_struct *tsk,
 450                                unsigned long idx,
 451                                u64 addr)
 452 {
 453         int err;
 454         struct perf_event *bp;
 455         struct perf_event_attr attr;
 456
 457         bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
 458         if (IS_ERR(bp)) {
 459                 err = PTR_ERR(bp);
 460                 return err;
 461         }
 462
 463         attr = bp->attr;
 464         attr.bp_addr = addr;
 465         err = modify_user_hw_breakpoint(bp, &attr);
 466         return err;
 467 }
 468
 469 #define PTRACE_HBP_ADDR_SZ      sizeof(u64)
 470 #define PTRACE_HBP_CTRL_SZ      sizeof(u32)
 471 #define PTRACE_HBP_PAD_SZ       sizeof(u32)
 472
 473 static int hw_break_get(struct task_struct *target,
 474                         const struct user_regset *regset,
 475                         struct membuf to)
 476 {
 477         unsigned int note_type = regset->core_note_type;
 478         int ret, idx = 0;
 479         u32 info, ctrl;
 480         u64 addr;
 481
 482         /* Resource info */
 483         ret = ptrace_hbp_get_resource_info(note_type, &info);
 484         if (ret)
 485                 return ret;
 486
 487         membuf_write(&to, &info, sizeof(info));
 488         membuf_zero(&to, sizeof(u32));
 489         /* (address, ctrl) registers */
 490         while (to.left) {
 491                 ret = ptrace_hbp_get_addr(note_type, target, idx, &addr);
 492                 if (ret)
 493                         return ret;
 494                 ret = ptrace_hbp_get_ctrl(note_type, target, idx, &ctrl);
 495                 if (ret)
 496                         return ret;
 497                 membuf_store(&to, addr);
 498                 membuf_store(&to, ctrl);
 499                 membuf_zero(&to, sizeof(u32));
 500                 idx++;
 501         }
 502         return 0;
 503 }
 504
 505 static int hw_break_set(struct task_struct *target,
 506                         const struct user_regset *regset,
 507                         unsigned int pos, unsigned int count,
 508                         const void *kbuf, const void __user *ubuf)
 509 {
 510         unsigned int note_type = regset->core_note_type;
 511         int ret, idx = 0, offset, limit;
 512         u32 ctrl;
 513         u64 addr;
 514
 515         /* Resource info and pad */
 516         offset = offsetof(struct user_hwdebug_state, dbg_regs);
 517         user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
 518
 519         /* (address, ctrl) registers */
 520         limit = regset->n * regset->size;
 521         while (count && offset < limit) {
 522                 if (count < PTRACE_HBP_ADDR_SZ)
 523                         return -EINVAL;
 524                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr,
 525                                          offset, offset + PTRACE_HBP_ADDR_SZ);
 526                 if (ret)
 527                         return ret;
 528                 ret = ptrace_hbp_set_addr(note_type, target, idx, addr);
 529                 if (ret)
 530                         return ret;
 531                 offset += PTRACE_HBP_ADDR_SZ;
 532
 533                 if (!count)
 534                         break;
 535                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl,
 536                                          offset, offset + PTRACE_HBP_CTRL_SZ);
 537                 if (ret)
 538                         return ret;
 539                 ret = ptrace_hbp_set_ctrl(note_type, target, idx, ctrl);
 540                 if (ret)
 541                         return ret;
 542                 offset += PTRACE_HBP_CTRL_SZ;
 543
 544                 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 545                                           offset, offset + PTRACE_HBP_PAD_SZ);
 546                 offset += PTRACE_HBP_PAD_SZ;
 547                 idx++;
 548         }
 549
 550         return 0;
 551 }
 552 #endif  /* CONFIG_HAVE_HW_BREAKPOINT */
 553
 554 static int gpr_get(struct task_struct *target,
 555                    const struct user_regset *regset,
 556                    struct membuf to)
 557 {
 558         struct user_pt_regs *uregs = &task_pt_regs(target)->user_regs;
 559         return membuf_write(&to, uregs, sizeof(*uregs));
 560 }
 561
 562 static int gpr_set(struct task_struct *target, const struct user_regset *regset,
 563                    unsigned int pos, unsigned int count,
 564                    const void *kbuf, const void __user *ubuf)
 565 {
 566         int ret;
 567         struct user_pt_regs newregs = task_pt_regs(target)->user_regs;
 568
 569         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1);
 570         if (ret)
 571                 return ret;
 572
 573         if (!valid_user_regs(&newregs, target))
 574                 return -EINVAL;
 575
 576         task_pt_regs(target)->user_regs = newregs;
 577         return 0;
 578 }
 579
 580 static int fpr_active(struct task_struct *target, const struct user_regset *regset)
 581 {
 582         if (!system_supports_fpsimd())
 583                 return -ENODEV;
 584         return regset->n;
 585 }
 586
 587 /*
 588  * TODO: update fp accessors for lazy context switching (sync/flush hwstate)
 589  */
 590 static int __fpr_get(struct task_struct *target,
 591                      const struct user_regset *regset,
 592                      struct membuf to)
 593 {
 594         struct user_fpsimd_state *uregs;
 595
 596         sve_sync_to_fpsimd(target);
 597
 598         uregs = &target->thread.uw.fpsimd_state;
 599
 600         return membuf_write(&to, uregs, sizeof(*uregs));
 601 }
 602
 603 static int fpr_get(struct task_struct *target, const struct user_regset *regset,
 604                    struct membuf to)
 605 {
 606         if (!system_supports_fpsimd())
 607                 return -EINVAL;
 608
 609         if (target == current)
 610                 fpsimd_preserve_current_state();
 611
 612         return __fpr_get(target, regset, to);
 613 }
 614
 615 static int __fpr_set(struct task_struct *target,
 616                      const struct user_regset *regset,
 617                      unsigned int pos, unsigned int count,
 618                      const void *kbuf, const void __user *ubuf,
 619                      unsigned int start_pos)
 620 {
 621         int ret;
 622         struct user_fpsimd_state newstate;
 623
 624         /*
 625          * Ensure target->thread.uw.fpsimd_state is up to date, so that a
 626          * short copyin can't resurrect stale data.
 627          */
 628         sve_sync_to_fpsimd(target);
 629
 630         newstate = target->thread.uw.fpsimd_state;
 631
 632         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate,
 633                                  start_pos, start_pos + sizeof(newstate));
 634         if (ret)
 635                 return ret;
 636
 637         target->thread.uw.fpsimd_state = newstate;
 638
 639         return ret;
 640 }
 641
 642 static int fpr_set(struct task_struct *target, const struct user_regset *regset,
 643                    unsigned int pos, unsigned int count,
 644                    const void *kbuf, const void __user *ubuf)
 645 {
 646         int ret;
 647
 648         if (!system_supports_fpsimd())
 649                 return -EINVAL;
 650
 651         ret = __fpr_set(target, regset, pos, count, kbuf, ubuf, 0);
 652         if (ret)
 653                 return ret;
 654
 655         sve_sync_from_fpsimd_zeropad(target);
 656         fpsimd_flush_task_state(target);
 657
 658         return ret;
 659 }
 660
 661 static int tls_get(struct task_struct *target, const struct user_regset *regset,
 662                    struct membuf to)
 663 {
 664         int ret;
 665
 666         if (target == current)
 667                 tls_preserve_current_state();
 668
 669         ret = membuf_store(&to, target->thread.uw.tp_value);
 670         if (system_supports_tpidr2())
 671                 ret = membuf_store(&to, target->thread.tpidr2_el0);
 672         else
 673                 ret = membuf_zero(&to, sizeof(u64));
 674
 675         return ret;
 676 }
 677
 678 static int tls_set(struct task_struct *target, const struct user_regset *regset,
 679                    unsigned int pos, unsigned int count,
 680                    const void *kbuf, const void __user *ubuf)
 681 {
 682         int ret;
 683         unsigned long tls[2];
 684
 685         tls[0] = target->thread.uw.tp_value;
 686         if (system_supports_tpidr2())
 687                 tls[1] = target->thread.tpidr2_el0;
 688
 689         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, tls, 0, count);
 690         if (ret)
 691                 return ret;
 692
 693         target->thread.uw.tp_value = tls[0];
 694         if (system_supports_tpidr2())
 695                 target->thread.tpidr2_el0 = tls[1];
 696
 697         return ret;
 698 }
 699
 700 static int system_call_get(struct task_struct *target,
 701                            const struct user_regset *regset,
 702                            struct membuf to)
 703 {
 704         return membuf_store(&to, task_pt_regs(target)->syscallno);
 705 }
 706
 707 static int system_call_set(struct task_struct *target,
 708                            const struct user_regset *regset,
 709                            unsigned int pos, unsigned int count,
 710                            const void *kbuf, const void __user *ubuf)
 711 {
 712         int syscallno = task_pt_regs(target)->syscallno;
 713         int ret;
 714
 715         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &syscallno, 0, -1);
 716         if (ret)
 717                 return ret;
 718
 719         task_pt_regs(target)->syscallno = syscallno;
 720         return ret;
 721 }
 722
 723 #ifdef CONFIG_ARM64_SVE
 724
 725 static void sve_init_header_from_task(struct user_sve_header *header,
 726                                       struct task_struct *target,
 727                                       enum vec_type type)
 728 {
 729         unsigned int vq;
 730         bool active;
 731         bool fpsimd_only;
 732         enum vec_type task_type;
 733
 734         memset(header, 0, sizeof(*header));
 735
 736         /* Check if the requested registers are active for the task */
 737         if (thread_sm_enabled(&target->thread))
 738                 task_type = ARM64_VEC_SME;
 739         else
 740                 task_type = ARM64_VEC_SVE;
 741         active = (task_type == type);
 742
 743         switch (type) {
 744         case ARM64_VEC_SVE:
 745                 if (test_tsk_thread_flag(target, TIF_SVE_VL_INHERIT))
 746                         header->flags |= SVE_PT_VL_INHERIT;
 747                 fpsimd_only = !test_tsk_thread_flag(target, TIF_SVE);
 748                 break;
 749         case ARM64_VEC_SME:
 750                 if (test_tsk_thread_flag(target, TIF_SME_VL_INHERIT))
 751                         header->flags |= SVE_PT_VL_INHERIT;
 752                 fpsimd_only = false;
 753                 break;
 754         default:
 755                 WARN_ON_ONCE(1);
 756                 return;
 757         }
 758
 759         if (active) {
 760                 if (fpsimd_only) {
 761                         header->flags |= SVE_PT_REGS_FPSIMD;
 762                 } else {
 763                         header->flags |= SVE_PT_REGS_SVE;
 764                 }
 765         }
 766
 767         header->vl = task_get_vl(target, type);
 768         vq = sve_vq_from_vl(header->vl);
 769
 770         header->max_vl = vec_max_vl(type);
 771         header->size = SVE_PT_SIZE(vq, header->flags);
 772         header->max_size = SVE_PT_SIZE(sve_vq_from_vl(header->max_vl),
 773                                       SVE_PT_REGS_SVE);
 774 }
 775
 776 static unsigned int sve_size_from_header(struct user_sve_header const *header)
 777 {
 778         return ALIGN(header->size, SVE_VQ_BYTES);
 779 }
 780
 781 static int sve_get_common(struct task_struct *target,
 782                           const struct user_regset *regset,
 783                           struct membuf to,
 784                           enum vec_type type)
 785 {
 786         struct user_sve_header header;
 787         unsigned int vq;
 788         unsigned long start, end;
 789
 790         /* Header */
 791         sve_init_header_from_task(&header, target, type);
 792         vq = sve_vq_from_vl(header.vl);
 793
 794         membuf_write(&to, &header, sizeof(header));
 795
 796         if (target == current)
 797                 fpsimd_preserve_current_state();
 798
 799         BUILD_BUG_ON(SVE_PT_FPSIMD_OFFSET != sizeof(header));
 800         BUILD_BUG_ON(SVE_PT_SVE_OFFSET != sizeof(header));
 801
 802         switch ((header.flags & SVE_PT_REGS_MASK)) {
 803         case SVE_PT_REGS_FPSIMD:
 804                 return __fpr_get(target, regset, to);
 805
 806         case SVE_PT_REGS_SVE:
 807                 start = SVE_PT_SVE_OFFSET;
 808                 end = SVE_PT_SVE_FFR_OFFSET(vq) + SVE_PT_SVE_FFR_SIZE(vq);
 809                 membuf_write(&to, target->thread.sve_state, end - start);
 810
 811                 start = end;
 812                 end = SVE_PT_SVE_FPSR_OFFSET(vq);
 813                 membuf_zero(&to, end - start);
 814
 815                 /*
 816                  * Copy fpsr, and fpcr which must follow contiguously in
 817                  * struct fpsimd_state:
 818                  */
 819                 start = end;
 820                 end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
 821                 membuf_write(&to, &target->thread.uw.fpsimd_state.fpsr,
 822                              end - start);
 823
 824                 start = end;
 825                 end = sve_size_from_header(&header);
 826                 return membuf_zero(&to, end - start);
 827
 828         default:
 829                 return 0;
 830         }
 831 }
 832
 833 static int sve_get(struct task_struct *target,
 834                    const struct user_regset *regset,
 835                    struct membuf to)
 836 {
 837         if (!system_supports_sve())
 838                 return -EINVAL;
 839
 840         return sve_get_common(target, regset, to, ARM64_VEC_SVE);
 841 }
 842
 843 static int sve_set_common(struct task_struct *target,
 844                           const struct user_regset *regset,
 845                           unsigned int pos, unsigned int count,
 846                           const void *kbuf, const void __user *ubuf,
 847                           enum vec_type type)
 848 {
 849         int ret;
 850         struct user_sve_header header;
 851         unsigned int vq;
 852         unsigned long start, end;
 853
 854         /* Header */
 855         if (count < sizeof(header))
 856                 return -EINVAL;
 857         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &header,
 858                                  0, sizeof(header));
 859         if (ret)
 860                 goto out;
 861
 862         /*
 863          * Apart from SVE_PT_REGS_MASK, all SVE_PT_* flags are consumed by
 864          * vec_set_vector_length(), which will also validate them for us:
 865          */
 866         ret = vec_set_vector_length(target, type, header.vl,
 867                 ((unsigned long)header.flags & ~SVE_PT_REGS_MASK) << 16);
 868         if (ret)
 869                 goto out;
 870
 871         /* Actual VL set may be less than the user asked for: */
 872         vq = sve_vq_from_vl(task_get_vl(target, type));
 873
 874         /* Enter/exit streaming mode */
 875         if (system_supports_sme()) {
 876                 u64 old_svcr = target->thread.svcr;
 877
 878                 switch (type) {
 879                 case ARM64_VEC_SVE:
 880                         target->thread.svcr &= ~SVCR_SM_MASK;
 881                         break;
 882                 case ARM64_VEC_SME:
 883                         target->thread.svcr |= SVCR_SM_MASK;
 884                         break;
 885                 default:
 886                         WARN_ON_ONCE(1);
 887                         return -EINVAL;
 888                 }
 889
 890                 /*
 891                  * If we switched then invalidate any existing SVE
 892                  * state and ensure there's storage.
 893                  */
 894                 if (target->thread.svcr != old_svcr)
 895                         sve_alloc(target, true);
 896         }
 897
 898         /* Registers: FPSIMD-only case */
 899
 900         BUILD_BUG_ON(SVE_PT_FPSIMD_OFFSET != sizeof(header));
 901         if ((header.flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_FPSIMD) {
 902                 ret = __fpr_set(target, regset, pos, count, kbuf, ubuf,
 903                                 SVE_PT_FPSIMD_OFFSET);
 904                 clear_tsk_thread_flag(target, TIF_SVE);
 905                 target->thread.fp_type = FP_STATE_FPSIMD;
 906                 goto out;
 907         }
 908
 909         /*
 910          * Otherwise: no registers or full SVE case.  For backwards
 911          * compatibility reasons we treat empty flags as SVE registers.
 912          */
 913
 914         /*
 915          * If setting a different VL from the requested VL and there is
 916          * register data, the data layout will be wrong: don't even
 917          * try to set the registers in this case.
 918          */
 919         if (count && vq != sve_vq_from_vl(header.vl)) {
 920                 ret = -EIO;
 921                 goto out;
 922         }
 923
 924         sve_alloc(target, true);
 925         if (!target->thread.sve_state) {
 926                 ret = -ENOMEM;
 927                 clear_tsk_thread_flag(target, TIF_SVE);
 928                 target->thread.fp_type = FP_STATE_FPSIMD;
 929                 goto out;
 930         }
 931
 932         /*
 933          * Ensure target->thread.sve_state is up to date with target's
 934          * FPSIMD regs, so that a short copyin leaves trailing
 935          * registers unmodified.  Always enable SVE even if going into
 936          * streaming mode.
 937          */
 938         fpsimd_sync_to_sve(target);
 939         set_tsk_thread_flag(target, TIF_SVE);
 940         target->thread.fp_type = FP_STATE_SVE;
 941
 942         BUILD_BUG_ON(SVE_PT_SVE_OFFSET != sizeof(header));
 943         start = SVE_PT_SVE_OFFSET;
 944         end = SVE_PT_SVE_FFR_OFFSET(vq) + SVE_PT_SVE_FFR_SIZE(vq);
 945         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 946                                  target->thread.sve_state,
 947                                  start, end);
 948         if (ret)
 949                 goto out;
 950
 951         start = end;
 952         end = SVE_PT_SVE_FPSR_OFFSET(vq);
 953         user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, start, end);
 954
 955         /*
 956          * Copy fpsr, and fpcr which must follow contiguously in
 957          * struct fpsimd_state:
 958          */
 959         start = end;
 960         end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
 961         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 962                                  &target->thread.uw.fpsimd_state.fpsr,
 963                                  start, end);
 964
 965 out:
 966         fpsimd_flush_task_state(target);
 967         return ret;
 968 }
 969
 970 static int sve_set(struct task_struct *target,
 971                    const struct user_regset *regset,
 972                    unsigned int pos, unsigned int count,
 973                    const void *kbuf, const void __user *ubuf)
 974 {
 975         if (!system_supports_sve())
 976                 return -EINVAL;
 977
 978         return sve_set_common(target, regset, pos, count, kbuf, ubuf,
 979                               ARM64_VEC_SVE);
 980 }
 981
 982 #endif /* CONFIG_ARM64_SVE */
 983
 984 #ifdef CONFIG_ARM64_SME
 985
 986 static int ssve_get(struct task_struct *target,
 987                    const struct user_regset *regset,
 988                    struct membuf to)
 989 {
 990         if (!system_supports_sme())
 991                 return -EINVAL;
 992
 993         return sve_get_common(target, regset, to, ARM64_VEC_SME);
 994 }
 995
 996 static int ssve_set(struct task_struct *target,
 997                     const struct user_regset *regset,
 998                     unsigned int pos, unsigned int count,
 999                     const void *kbuf, const void __user *ubuf)
1000 {
1001         if (!system_supports_sme())
1002                 return -EINVAL;
1003
1004         return sve_set_common(target, regset, pos, count, kbuf, ubuf,
1005                               ARM64_VEC_SME);
1006 }
1007
1008 static int za_get(struct task_struct *target,
1009                   const struct user_regset *regset,
1010                   struct membuf to)
1011 {
1012         struct user_za_header header;
1013         unsigned int vq;
1014         unsigned long start, end;
1015
1016         if (!system_supports_sme())
1017                 return -EINVAL;
1018
1019         /* Header */
1020         memset(&header, 0, sizeof(header));
1021
1022         if (test_tsk_thread_flag(target, TIF_SME_VL_INHERIT))
1023                 header.flags |= ZA_PT_VL_INHERIT;
1024
1025         header.vl = task_get_sme_vl(target);
1026         vq = sve_vq_from_vl(header.vl);
1027         header.max_vl = sme_max_vl();
1028         header.max_size = ZA_PT_SIZE(vq);
1029
1030         /* If ZA is not active there is only the header */
1031         if (thread_za_enabled(&target->thread))
1032                 header.size = ZA_PT_SIZE(vq);
1033         else
1034                 header.size = ZA_PT_ZA_OFFSET;
1035
1036         membuf_write(&to, &header, sizeof(header));
1037
1038         BUILD_BUG_ON(ZA_PT_ZA_OFFSET != sizeof(header));
1039         end = ZA_PT_ZA_OFFSET;
1040
1041         if (target == current)
1042                 fpsimd_preserve_current_state();
1043
1044         /* Any register data to include? */
1045         if (thread_za_enabled(&target->thread)) {
1046                 start = end;
1047                 end = ZA_PT_SIZE(vq);
1048                 membuf_write(&to, target->thread.sme_state, end - start);
1049         }
1050
1051         /* Zero any trailing padding */
1052         start = end;
1053         end = ALIGN(header.size, SVE_VQ_BYTES);
1054         return membuf_zero(&to, end - start);
1055 }
1056
1057 static int za_set(struct task_struct *target,
1058                   const struct user_regset *regset,
1059                   unsigned int pos, unsigned int count,
1060                   const void *kbuf, const void __user *ubuf)
1061 {
1062         int ret;
1063         struct user_za_header header;
1064         unsigned int vq;
1065         unsigned long start, end;
1066
1067         if (!system_supports_sme())
1068                 return -EINVAL;
1069
1070         /* Header */
1071         if (count < sizeof(header))
1072                 return -EINVAL;
1073         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &header,
1074                                  0, sizeof(header));
1075         if (ret)
1076                 goto out;
1077
1078         /*
1079          * All current ZA_PT_* flags are consumed by
1080          * vec_set_vector_length(), which will also validate them for
1081          * us:
1082          */
1083         ret = vec_set_vector_length(target, ARM64_VEC_SME, header.vl,
1084                 ((unsigned long)header.flags) << 16);
1085         if (ret)
1086                 goto out;
1087
1088         /* Actual VL set may be less than the user asked for: */
1089         vq = sve_vq_from_vl(task_get_sme_vl(target));
1090
1091         /* Ensure there is some SVE storage for streaming mode */
1092         if (!target->thread.sve_state) {
1093                 sve_alloc(target, false);
1094                 if (!target->thread.sve_state) {
1095                         ret = -ENOMEM;
1096                         goto out;
1097                 }
1098         }
1099
1100         /* Allocate/reinit ZA storage */
1101         sme_alloc(target);
1102         if (!target->thread.sme_state) {
1103                 ret = -ENOMEM;
1104                 goto out;
1105         }
1106
1107         /* If there is no data then disable ZA */
1108         if (!count) {
1109                 target->thread.svcr &= ~SVCR_ZA_MASK;
1110                 goto out;
1111         }
1112
1113         /*
1114          * If setting a different VL from the requested VL and there is
1115          * register data, the data layout will be wrong: don't even
1116          * try to set the registers in this case.
1117          */
1118         if (vq != sve_vq_from_vl(header.vl)) {
1119                 ret = -EIO;
1120                 goto out;
1121         }
1122
1123         BUILD_BUG_ON(ZA_PT_ZA_OFFSET != sizeof(header));
1124         start = ZA_PT_ZA_OFFSET;
1125         end = ZA_PT_SIZE(vq);
1126         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1127                                  target->thread.sme_state,
1128                                  start, end);
1129         if (ret)
1130                 goto out;
1131
1132         /* Mark ZA as active and let userspace use it */
1133         set_tsk_thread_flag(target, TIF_SME);
1134         target->thread.svcr |= SVCR_ZA_MASK;
1135
1136 out:
1137         fpsimd_flush_task_state(target);
1138         return ret;
1139 }
1140
1141 static int zt_get(struct task_struct *target,
1142                   const struct user_regset *regset,
1143                   struct membuf to)
1144 {
1145         if (!system_supports_sme2())
1146                 return -EINVAL;
1147
1148         /*
1149          * If PSTATE.ZA is not set then ZT will be zeroed when it is
1150          * enabled so report the current register value as zero.
1151          */
1152         if (thread_za_enabled(&target->thread))
1153                 membuf_write(&to, thread_zt_state(&target->thread),
1154                              ZT_SIG_REG_BYTES);
1155         else
1156                 membuf_zero(&to, ZT_SIG_REG_BYTES);
1157
1158         return 0;
1159 }
1160
1161 static int zt_set(struct task_struct *target,
1162                   const struct user_regset *regset,
1163                   unsigned int pos, unsigned int count,
1164                   const void *kbuf, const void __user *ubuf)
1165 {
1166         int ret;
1167
1168         if (!system_supports_sme2())
1169                 return -EINVAL;
1170
1171         if (!thread_za_enabled(&target->thread)) {
1172                 sme_alloc(target);
1173                 if (!target->thread.sme_state)
1174                         return -ENOMEM;
1175         }
1176
1177         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1178                                  thread_zt_state(&target->thread),
1179                                  0, ZT_SIG_REG_BYTES);
1180         if (ret == 0)
1181                 target->thread.svcr |= SVCR_ZA_MASK;
1182
1183         return ret;
1184 }
1185
1186 #endif /* CONFIG_ARM64_SME */
1187
1188 #ifdef CONFIG_ARM64_PTR_AUTH
1189 static int pac_mask_get(struct task_struct *target,
1190                         const struct user_regset *regset,
1191                         struct membuf to)
1192 {
1193         /*
1194          * The PAC bits can differ across data and instruction pointers
1195          * depending on TCR_EL1.TBID*, which we may make use of in future, so
1196          * we expose separate masks.
1197          */
1198         unsigned long mask = ptrauth_user_pac_mask();
1199         struct user_pac_mask uregs = {
1200                 .data_mask = mask,
1201                 .insn_mask = mask,
1202         };
1203
1204         if (!system_supports_address_auth())
1205                 return -EINVAL;
1206
1207         return membuf_write(&to, &uregs, sizeof(uregs));
1208 }
1209
1210 static int pac_enabled_keys_get(struct task_struct *target,
1211                                 const struct user_regset *regset,
1212                                 struct membuf to)
1213 {
1214         long enabled_keys = ptrauth_get_enabled_keys(target);
1215
1216         if (IS_ERR_VALUE(enabled_keys))
1217                 return enabled_keys;
1218
1219         return membuf_write(&to, &enabled_keys, sizeof(enabled_keys));
1220 }
1221
1222 static int pac_enabled_keys_set(struct task_struct *target,
1223                                 const struct user_regset *regset,
1224                                 unsigned int pos, unsigned int count,
1225                                 const void *kbuf, const void __user *ubuf)
1226 {
1227         int ret;
1228         long enabled_keys = ptrauth_get_enabled_keys(target);
1229
1230         if (IS_ERR_VALUE(enabled_keys))
1231                 return enabled_keys;
1232
1233         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &enabled_keys, 0,
1234                                  sizeof(long));
1235         if (ret)
1236                 return ret;
1237
1238         return ptrauth_set_enabled_keys(target, PR_PAC_ENABLED_KEYS_MASK,
1239                                         enabled_keys);
1240 }
1241
1242 #ifdef CONFIG_CHECKPOINT_RESTORE
1243 static __uint128_t pac_key_to_user(const struct ptrauth_key *key)
1244 {
1245         return (__uint128_t)key->hi << 64 | key->lo;
1246 }
1247
1248 static struct ptrauth_key pac_key_from_user(__uint128_t ukey)
1249 {
1250         struct ptrauth_key key = {
1251                 .lo = (unsigned long)ukey,
1252                 .hi = (unsigned long)(ukey >> 64),
1253         };
1254
1255         return key;
1256 }
1257
1258 static void pac_address_keys_to_user(struct user_pac_address_keys *ukeys,
1259                                      const struct ptrauth_keys_user *keys)
1260 {
1261         ukeys->apiakey = pac_key_to_user(&keys->apia);
1262         ukeys->apibkey = pac_key_to_user(&keys->apib);
1263         ukeys->apdakey = pac_key_to_user(&keys->apda);
1264         ukeys->apdbkey = pac_key_to_user(&keys->apdb);
1265 }
1266
1267 static void pac_address_keys_from_user(struct ptrauth_keys_user *keys,
1268                                        const struct user_pac_address_keys *ukeys)
1269 {
1270         keys->apia = pac_key_from_user(ukeys->apiakey);
1271         keys->apib = pac_key_from_user(ukeys->apibkey);
1272         keys->apda = pac_key_from_user(ukeys->apdakey);
1273         keys->apdb = pac_key_from_user(ukeys->apdbkey);
1274 }
1275
1276 static int pac_address_keys_get(struct task_struct *target,
1277                                 const struct user_regset *regset,
1278                                 struct membuf to)
1279 {
1280         struct ptrauth_keys_user *keys = &target->thread.keys_user;
1281         struct user_pac_address_keys user_keys;
1282
1283         if (!system_supports_address_auth())
1284                 return -EINVAL;
1285
1286         pac_address_keys_to_user(&user_keys, keys);
1287
1288         return membuf_write(&to, &user_keys, sizeof(user_keys));
1289 }
1290
1291 static int pac_address_keys_set(struct task_struct *target,
1292                                 const struct user_regset *regset,
1293                                 unsigned int pos, unsigned int count,
1294                                 const void *kbuf, const void __user *ubuf)
1295 {
1296         struct ptrauth_keys_user *keys = &target->thread.keys_user;
1297         struct user_pac_address_keys user_keys;
1298         int ret;
1299
1300         if (!system_supports_address_auth())
1301                 return -EINVAL;
1302
1303         pac_address_keys_to_user(&user_keys, keys);
1304         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1305                                  &user_keys, 0, -1);
1306         if (ret)
1307                 return ret;
1308         pac_address_keys_from_user(keys, &user_keys);
1309
1310         return 0;
1311 }
1312
1313 static void pac_generic_keys_to_user(struct user_pac_generic_keys *ukeys,
1314                                      const struct ptrauth_keys_user *keys)
1315 {
1316         ukeys->apgakey = pac_key_to_user(&keys->apga);
1317 }
1318
1319 static void pac_generic_keys_from_user(struct ptrauth_keys_user *keys,
1320                                        const struct user_pac_generic_keys *ukeys)
1321 {
1322         keys->apga = pac_key_from_user(ukeys->apgakey);
1323 }
1324
1325 static int pac_generic_keys_get(struct task_struct *target,
1326                                 const struct user_regset *regset,
1327                                 struct membuf to)
1328 {
1329         struct ptrauth_keys_user *keys = &target->thread.keys_user;
1330         struct user_pac_generic_keys user_keys;
1331
1332         if (!system_supports_generic_auth())
1333                 return -EINVAL;
1334
1335         pac_generic_keys_to_user(&user_keys, keys);
1336
1337         return membuf_write(&to, &user_keys, sizeof(user_keys));
1338 }
1339
1340 static int pac_generic_keys_set(struct task_struct *target,
1341                                 const struct user_regset *regset,
1342                                 unsigned int pos, unsigned int count,
1343                                 const void *kbuf, const void __user *ubuf)
1344 {
1345         struct ptrauth_keys_user *keys = &target->thread.keys_user;
1346         struct user_pac_generic_keys user_keys;
1347         int ret;
1348
1349         if (!system_supports_generic_auth())
1350                 return -EINVAL;
1351
1352         pac_generic_keys_to_user(&user_keys, keys);
1353         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1354                                  &user_keys, 0, -1);
1355         if (ret)
1356                 return ret;
1357         pac_generic_keys_from_user(keys, &user_keys);
1358
1359         return 0;
1360 }
1361 #endif /* CONFIG_CHECKPOINT_RESTORE */
1362 #endif /* CONFIG_ARM64_PTR_AUTH */
1363
1364 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1365 static int tagged_addr_ctrl_get(struct task_struct *target,
1366                                 const struct user_regset *regset,
1367                                 struct membuf to)
1368 {
1369         long ctrl = get_tagged_addr_ctrl(target);
1370
1371         if (IS_ERR_VALUE(ctrl))
1372                 return ctrl;
1373
1374         return membuf_write(&to, &ctrl, sizeof(ctrl));
1375 }
1376
1377 static int tagged_addr_ctrl_set(struct task_struct *target, const struct
1378                                 user_regset *regset, unsigned int pos,
1379                                 unsigned int count, const void *kbuf, const
1380                                 void __user *ubuf)
1381 {
1382         int ret;
1383         long ctrl;
1384
1385         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl, 0, -1);
1386         if (ret)
1387                 return ret;
1388
1389         return set_tagged_addr_ctrl(target, ctrl);
1390 }
1391 #endif
1392
1393 enum aarch64_regset {
1394         REGSET_GPR,
1395         REGSET_FPR,
1396         REGSET_TLS,
1397 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1398         REGSET_HW_BREAK,
1399         REGSET_HW_WATCH,
1400 #endif
1401         REGSET_SYSTEM_CALL,
1402 #ifdef CONFIG_ARM64_SVE
1403         REGSET_SVE,
1404 #endif
1405 #ifdef CONFIG_ARM64_SVE
1406         REGSET_SSVE,
1407         REGSET_ZA,
1408         REGSET_ZT,
1409 #endif
1410 #ifdef CONFIG_ARM64_PTR_AUTH
1411         REGSET_PAC_MASK,
1412         REGSET_PAC_ENABLED_KEYS,
1413 #ifdef CONFIG_CHECKPOINT_RESTORE
1414         REGSET_PACA_KEYS,
1415         REGSET_PACG_KEYS,
1416 #endif
1417 #endif
1418 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1419         REGSET_TAGGED_ADDR_CTRL,
1420 #endif
1421 };
1422
1423 static const struct user_regset aarch64_regsets[] = {
1424         [REGSET_GPR] = {
1425                 .core_note_type = NT_PRSTATUS,
1426                 .n = sizeof(struct user_pt_regs) / sizeof(u64),
1427                 .size = sizeof(u64),
1428                 .align = sizeof(u64),
1429                 .regset_get = gpr_get,
1430                 .set = gpr_set
1431         },
1432         [REGSET_FPR] = {
1433                 .core_note_type = NT_PRFPREG,
1434                 .n = sizeof(struct user_fpsimd_state) / sizeof(u32),
1435                 /*
1436                  * We pretend we have 32-bit registers because the fpsr and
1437                  * fpcr are 32-bits wide.
1438                  */
1439                 .size = sizeof(u32),
1440                 .align = sizeof(u32),
1441                 .active = fpr_active,
1442                 .regset_get = fpr_get,
1443                 .set = fpr_set
1444         },
1445         [REGSET_TLS] = {
1446                 .core_note_type = NT_ARM_TLS,
1447                 .n = 2,
1448                 .size = sizeof(void *),
1449                 .align = sizeof(void *),
1450                 .regset_get = tls_get,
1451                 .set = tls_set,
1452         },
1453 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1454         [REGSET_HW_BREAK] = {
1455                 .core_note_type = NT_ARM_HW_BREAK,
1456                 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1457                 .size = sizeof(u32),
1458                 .align = sizeof(u32),
1459                 .regset_get = hw_break_get,
1460                 .set = hw_break_set,
1461         },
1462         [REGSET_HW_WATCH] = {
1463                 .core_note_type = NT_ARM_HW_WATCH,
1464                 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1465                 .size = sizeof(u32),
1466                 .align = sizeof(u32),
1467                 .regset_get = hw_break_get,
1468                 .set = hw_break_set,
1469         },
1470 #endif
1471         [REGSET_SYSTEM_CALL] = {
1472                 .core_note_type = NT_ARM_SYSTEM_CALL,
1473                 .n = 1,
1474                 .size = sizeof(int),
1475                 .align = sizeof(int),
1476                 .regset_get = system_call_get,
1477                 .set = system_call_set,
1478         },
1479 #ifdef CONFIG_ARM64_SVE
1480         [REGSET_SVE] = { /* Scalable Vector Extension */
1481                 .core_note_type = NT_ARM_SVE,
1482                 .n = DIV_ROUND_UP(SVE_PT_SIZE(SVE_VQ_MAX, SVE_PT_REGS_SVE),
1483                                   SVE_VQ_BYTES),
1484                 .size = SVE_VQ_BYTES,
1485                 .align = SVE_VQ_BYTES,
1486                 .regset_get = sve_get,
1487                 .set = sve_set,
1488         },
1489 #endif
1490 #ifdef CONFIG_ARM64_SME
1491         [REGSET_SSVE] = { /* Streaming mode SVE */
1492                 .core_note_type = NT_ARM_SSVE,
1493                 .n = DIV_ROUND_UP(SVE_PT_SIZE(SME_VQ_MAX, SVE_PT_REGS_SVE),
1494                                   SVE_VQ_BYTES),
1495                 .size = SVE_VQ_BYTES,
1496                 .align = SVE_VQ_BYTES,
1497                 .regset_get = ssve_get,
1498                 .set = ssve_set,
1499         },
1500         [REGSET_ZA] = { /* SME ZA */
1501                 .core_note_type = NT_ARM_ZA,
1502                 /*
1503                  * ZA is a single register but it's variably sized and
1504                  * the ptrace core requires that the size of any data
1505                  * be an exact multiple of the configured register
1506                  * size so report as though we had SVE_VQ_BYTES
1507                  * registers. These values aren't exposed to
1508                  * userspace.
1509                  */
1510                 .n = DIV_ROUND_UP(ZA_PT_SIZE(SME_VQ_MAX), SVE_VQ_BYTES),
1511                 .size = SVE_VQ_BYTES,
1512                 .align = SVE_VQ_BYTES,
1513                 .regset_get = za_get,
1514                 .set = za_set,
1515         },
1516         [REGSET_ZT] = { /* SME ZT */
1517                 .core_note_type = NT_ARM_ZT,
1518                 .n = 1,
1519                 .size = ZT_SIG_REG_BYTES,
1520                 .align = sizeof(u64),
1521                 .regset_get = zt_get,
1522                 .set = zt_set,
1523         },
1524 #endif
1525 #ifdef CONFIG_ARM64_PTR_AUTH
1526         [REGSET_PAC_MASK] = {
1527                 .core_note_type = NT_ARM_PAC_MASK,
1528                 .n = sizeof(struct user_pac_mask) / sizeof(u64),
1529                 .size = sizeof(u64),
1530                 .align = sizeof(u64),
1531                 .regset_get = pac_mask_get,
1532                 /* this cannot be set dynamically */
1533         },
1534         [REGSET_PAC_ENABLED_KEYS] = {
1535                 .core_note_type = NT_ARM_PAC_ENABLED_KEYS,
1536                 .n = 1,
1537                 .size = sizeof(long),
1538                 .align = sizeof(long),
1539                 .regset_get = pac_enabled_keys_get,
1540                 .set = pac_enabled_keys_set,
1541         },
1542 #ifdef CONFIG_CHECKPOINT_RESTORE
1543         [REGSET_PACA_KEYS] = {
1544                 .core_note_type = NT_ARM_PACA_KEYS,
1545                 .n = sizeof(struct user_pac_address_keys) / sizeof(__uint128_t),
1546                 .size = sizeof(__uint128_t),
1547                 .align = sizeof(__uint128_t),
1548                 .regset_get = pac_address_keys_get,
1549                 .set = pac_address_keys_set,
1550         },
1551         [REGSET_PACG_KEYS] = {
1552                 .core_note_type = NT_ARM_PACG_KEYS,
1553                 .n = sizeof(struct user_pac_generic_keys) / sizeof(__uint128_t),
1554                 .size = sizeof(__uint128_t),
1555                 .align = sizeof(__uint128_t),
1556                 .regset_get = pac_generic_keys_get,
1557                 .set = pac_generic_keys_set,
1558         },
1559 #endif
1560 #endif
1561 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1562         [REGSET_TAGGED_ADDR_CTRL] = {
1563                 .core_note_type = NT_ARM_TAGGED_ADDR_CTRL,
1564                 .n = 1,
1565                 .size = sizeof(long),
1566                 .align = sizeof(long),
1567                 .regset_get = tagged_addr_ctrl_get,
1568                 .set = tagged_addr_ctrl_set,
1569         },
1570 #endif
1571 };
1572
1573 static const struct user_regset_view user_aarch64_view = {
1574         .name = "aarch64", .e_machine = EM_AARCH64,
1575         .regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
1576 };
1577
1578 #ifdef CONFIG_COMPAT
1579 enum compat_regset {
1580         REGSET_COMPAT_GPR,
1581         REGSET_COMPAT_VFP,
1582 };
1583
1584 static inline compat_ulong_t compat_get_user_reg(struct task_struct *task, int idx)
1585 {
1586         struct pt_regs *regs = task_pt_regs(task);
1587
1588         switch (idx) {
1589         case 15:
1590                 return regs->pc;
1591         case 16:
1592                 return pstate_to_compat_psr(regs->pstate);
1593         case 17:
1594                 return regs->orig_x0;
1595         default:
1596                 return regs->regs[idx];
1597         }
1598 }
1599
1600 static int compat_gpr_get(struct task_struct *target,
1601                           const struct user_regset *regset,
1602                           struct membuf to)
1603 {
1604         int i = 0;
1605
1606         while (to.left)
1607                 membuf_store(&to, compat_get_user_reg(target, i++));
1608         return 0;
1609 }
1610
1611 static int compat_gpr_set(struct task_struct *target,
1612                           const struct user_regset *regset,
1613                           unsigned int pos, unsigned int count,
1614                           const void *kbuf, const void __user *ubuf)
1615 {
1616         struct pt_regs newregs;
1617         int ret = 0;
1618         unsigned int i, start, num_regs;
1619
1620         /* Calculate the number of AArch32 registers contained in count */
1621         num_regs = count / regset->size;
1622
1623         /* Convert pos into an register number */
1624         start = pos / regset->size;
1625
1626         if (start + num_regs > regset->n)
1627                 return -EIO;
1628
1629         newregs = *task_pt_regs(target);
1630
1631         for (i = 0; i < num_regs; ++i) {
1632                 unsigned int idx = start + i;
1633                 compat_ulong_t reg;
1634
1635                 if (kbuf) {
1636                         memcpy(&reg, kbuf, sizeof(reg));
1637                         kbuf += sizeof(reg);
1638                 } else {
1639                         ret = copy_from_user(&reg, ubuf, sizeof(reg));
1640                         if (ret) {
1641                                 ret = -EFAULT;
1642                                 break;
1643                         }
1644
1645                         ubuf += sizeof(reg);
1646                 }
1647
1648                 switch (idx) {
1649                 case 15:
1650                         newregs.pc = reg;
1651                         break;
1652                 case 16:
1653                         reg = compat_psr_to_pstate(reg);
1654                         newregs.pstate = reg;
1655                         break;
1656                 case 17:
1657                         newregs.orig_x0 = reg;
1658                         break;
1659                 default:
1660                         newregs.regs[idx] = reg;
1661                 }
1662
1663         }
1664
1665         if (valid_user_regs(&newregs.user_regs, target))
1666                 *task_pt_regs(target) = newregs;
1667         else
1668                 ret = -EINVAL;
1669
1670         return ret;
1671 }
1672
1673 static int compat_vfp_get(struct task_struct *target,
1674                           const struct user_regset *regset,
1675                           struct membuf to)
1676 {
1677         struct user_fpsimd_state *uregs;
1678         compat_ulong_t fpscr;
1679
1680         if (!system_supports_fpsimd())
1681                 return -EINVAL;
1682
1683         uregs = &target->thread.uw.fpsimd_state;
1684
1685         if (target == current)
1686                 fpsimd_preserve_current_state();
1687
1688         /*
1689          * The VFP registers are packed into the fpsimd_state, so they all sit
1690          * nicely together for us. We just need to create the fpscr separately.
1691          */
1692         membuf_write(&to, uregs, VFP_STATE_SIZE - sizeof(compat_ulong_t));
1693         fpscr = (uregs->fpsr & VFP_FPSCR_STAT_MASK) |
1694                 (uregs->fpcr & VFP_FPSCR_CTRL_MASK);
1695         return membuf_store(&to, fpscr);
1696 }
1697
1698 static int compat_vfp_set(struct task_struct *target,
1699                           const struct user_regset *regset,
1700                           unsigned int pos, unsigned int count,
1701                           const void *kbuf, const void __user *ubuf)
1702 {
1703         struct user_fpsimd_state *uregs;
1704         compat_ulong_t fpscr;
1705         int ret, vregs_end_pos;
1706
1707         if (!system_supports_fpsimd())
1708                 return -EINVAL;
1709
1710         uregs = &target->thread.uw.fpsimd_state;
1711
1712         vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t);
1713         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
1714                                  vregs_end_pos);
1715
1716         if (count && !ret) {
1717                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpscr,
1718                                          vregs_end_pos, VFP_STATE_SIZE);
1719                 if (!ret) {
1720                         uregs->fpsr = fpscr & VFP_FPSCR_STAT_MASK;
1721                         uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
1722                 }
1723         }
1724
1725         fpsimd_flush_task_state(target);
1726         return ret;
1727 }
1728
1729 static int compat_tls_get(struct task_struct *target,
1730                           const struct user_regset *regset,
1731                           struct membuf to)
1732 {
1733         return membuf_store(&to, (compat_ulong_t)target->thread.uw.tp_value);
1734 }
1735
1736 static int compat_tls_set(struct task_struct *target,
1737                           const struct user_regset *regset, unsigned int pos,
1738                           unsigned int count, const void *kbuf,
1739                           const void __user *ubuf)
1740 {
1741         int ret;
1742         compat_ulong_t tls = target->thread.uw.tp_value;
1743
1744         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
1745         if (ret)
1746                 return ret;
1747
1748         target->thread.uw.tp_value = tls;
1749         return ret;
1750 }
1751
1752 static const struct user_regset aarch32_regsets[] = {
1753         [REGSET_COMPAT_GPR] = {
1754                 .core_note_type = NT_PRSTATUS,
1755                 .n = COMPAT_ELF_NGREG,
1756                 .size = sizeof(compat_elf_greg_t),
1757                 .align = sizeof(compat_elf_greg_t),
1758                 .regset_get = compat_gpr_get,
1759                 .set = compat_gpr_set
1760         },
1761         [REGSET_COMPAT_VFP] = {
1762                 .core_note_type = NT_ARM_VFP,
1763                 .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
1764                 .size = sizeof(compat_ulong_t),
1765                 .align = sizeof(compat_ulong_t),
1766                 .active = fpr_active,
1767                 .regset_get = compat_vfp_get,
1768                 .set = compat_vfp_set
1769         },
1770 };
1771
1772 static const struct user_regset_view user_aarch32_view = {
1773         .name = "aarch32", .e_machine = EM_ARM,
1774         .regsets = aarch32_regsets, .n = ARRAY_SIZE(aarch32_regsets)
1775 };
1776
1777 static const struct user_regset aarch32_ptrace_regsets[] = {
1778         [REGSET_GPR] = {
1779                 .core_note_type = NT_PRSTATUS,
1780                 .n = COMPAT_ELF_NGREG,
1781                 .size = sizeof(compat_elf_greg_t),
1782                 .align = sizeof(compat_elf_greg_t),
1783                 .regset_get = compat_gpr_get,
1784                 .set = compat_gpr_set
1785         },
1786         [REGSET_FPR] = {
1787                 .core_note_type = NT_ARM_VFP,
1788                 .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
1789                 .size = sizeof(compat_ulong_t),
1790                 .align = sizeof(compat_ulong_t),
1791                 .regset_get = compat_vfp_get,
1792                 .set = compat_vfp_set
1793         },
1794         [REGSET_TLS] = {
1795                 .core_note_type = NT_ARM_TLS,
1796                 .n = 1,
1797                 .size = sizeof(compat_ulong_t),
1798                 .align = sizeof(compat_ulong_t),
1799                 .regset_get = compat_tls_get,
1800                 .set = compat_tls_set,
1801         },
1802 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1803         [REGSET_HW_BREAK] = {
1804                 .core_note_type = NT_ARM_HW_BREAK,
1805                 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1806                 .size = sizeof(u32),
1807                 .align = sizeof(u32),
1808                 .regset_get = hw_break_get,
1809                 .set = hw_break_set,
1810         },
1811         [REGSET_HW_WATCH] = {
1812                 .core_note_type = NT_ARM_HW_WATCH,
1813                 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1814                 .size = sizeof(u32),
1815                 .align = sizeof(u32),
1816                 .regset_get = hw_break_get,
1817                 .set = hw_break_set,
1818         },
1819 #endif
1820         [REGSET_SYSTEM_CALL] = {
1821                 .core_note_type = NT_ARM_SYSTEM_CALL,
1822                 .n = 1,
1823                 .size = sizeof(int),
1824                 .align = sizeof(int),
1825                 .regset_get = system_call_get,
1826                 .set = system_call_set,
1827         },
1828 };
1829
1830 static const struct user_regset_view user_aarch32_ptrace_view = {
1831         .name = "aarch32", .e_machine = EM_ARM,
1832         .regsets = aarch32_ptrace_regsets, .n = ARRAY_SIZE(aarch32_ptrace_regsets)
1833 };
1834
1835 static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
1836                                    compat_ulong_t __user *ret)
1837 {
1838         compat_ulong_t tmp;
1839
1840         if (off & 3)
1841                 return -EIO;
1842
1843         if (off == COMPAT_PT_TEXT_ADDR)
1844                 tmp = tsk->mm->start_code;
1845         else if (off == COMPAT_PT_DATA_ADDR)
1846                 tmp = tsk->mm->start_data;
1847         else if (off == COMPAT_PT_TEXT_END_ADDR)
1848                 tmp = tsk->mm->end_code;
1849         else if (off < sizeof(compat_elf_gregset_t))
1850                 tmp = compat_get_user_reg(tsk, off >> 2);
1851         else if (off >= COMPAT_USER_SZ)
1852                 return -EIO;
1853         else
1854                 tmp = 0;
1855
1856         return put_user(tmp, ret);
1857 }
1858
1859 static int compat_ptrace_write_user(struct task_struct *tsk, compat_ulong_t off,
1860                                     compat_ulong_t val)
1861 {
1862         struct pt_regs newregs = *task_pt_regs(tsk);
1863         unsigned int idx = off / 4;
1864
1865         if (off & 3 || off >= COMPAT_USER_SZ)
1866                 return -EIO;
1867
1868         if (off >= sizeof(compat_elf_gregset_t))
1869                 return 0;
1870
1871         switch (idx) {
1872         case 15:
1873                 newregs.pc = val;
1874                 break;
1875         case 16:
1876                 newregs.pstate = compat_psr_to_pstate(val);
1877                 break;
1878         case 17:
1879                 newregs.orig_x0 = val;
1880                 break;
1881         default:
1882                 newregs.regs[idx] = val;
1883         }
1884
1885         if (!valid_user_regs(&newregs.user_regs, tsk))
1886                 return -EINVAL;
1887
1888         *task_pt_regs(tsk) = newregs;
1889         return 0;
1890 }
1891
1892 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1893
1894 /*
1895  * Convert a virtual register number into an index for a thread_info
1896  * breakpoint array. Breakpoints are identified using positive numbers
1897  * whilst watchpoints are negative. The registers are laid out as pairs
1898  * of (address, control), each pair mapping to a unique hw_breakpoint struct.
1899  * Register 0 is reserved for describing resource information.
1900  */
1901 static int compat_ptrace_hbp_num_to_idx(compat_long_t num)
1902 {
1903         return (abs(num) - 1) >> 1;
1904 }
1905
1906 static int compat_ptrace_hbp_get_resource_info(u32 *kdata)
1907 {
1908         u8 num_brps, num_wrps, debug_arch, wp_len;
1909         u32 reg = 0;
1910
1911         num_brps        = hw_breakpoint_slots(TYPE_INST);
1912         num_wrps        = hw_breakpoint_slots(TYPE_DATA);
1913
1914         debug_arch      = debug_monitors_arch();
1915         wp_len          = 8;
1916         reg             |= debug_arch;
1917         reg             <<= 8;
1918         reg             |= wp_len;
1919         reg             <<= 8;
1920         reg             |= num_wrps;
1921         reg             <<= 8;
1922         reg             |= num_brps;
1923
1924         *kdata = reg;
1925         return 0;
1926 }
1927
1928 static int compat_ptrace_hbp_get(unsigned int note_type,
1929                                  struct task_struct *tsk,
1930                                  compat_long_t num,
1931                                  u32 *kdata)
1932 {
1933         u64 addr = 0;
1934         u32 ctrl = 0;
1935
1936         int err, idx = compat_ptrace_hbp_num_to_idx(num);
1937
1938         if (num & 1) {
1939                 err = ptrace_hbp_get_addr(note_type, tsk, idx, &addr);
1940                 *kdata = (u32)addr;
1941         } else {
1942                 err = ptrace_hbp_get_ctrl(note_type, tsk, idx, &ctrl);
1943                 *kdata = ctrl;
1944         }
1945
1946         return err;
1947 }
1948
1949 static int compat_ptrace_hbp_set(unsigned int note_type,
1950                                  struct task_struct *tsk,
1951                                  compat_long_t num,
1952                                  u32 *kdata)
1953 {
1954         u64 addr;
1955         u32 ctrl;
1956
1957         int err, idx = compat_ptrace_hbp_num_to_idx(num);
1958
1959         if (num & 1) {
1960                 addr = *kdata;
1961                 err = ptrace_hbp_set_addr(note_type, tsk, idx, addr);
1962         } else {
1963                 ctrl = *kdata;
1964                 err = ptrace_hbp_set_ctrl(note_type, tsk, idx, ctrl);
1965         }
1966
1967         return err;
1968 }
1969
1970 static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
1971                                     compat_ulong_t __user *data)
1972 {
1973         int ret;
1974         u32 kdata;
1975
1976         /* Watchpoint */
1977         if (num < 0) {
1978                 ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
1979         /* Resource info */
1980         } else if (num == 0) {
1981                 ret = compat_ptrace_hbp_get_resource_info(&kdata);
1982         /* Breakpoint */
1983         } else {
1984                 ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
1985         }
1986
1987         if (!ret)
1988                 ret = put_user(kdata, data);
1989
1990         return ret;
1991 }
1992
1993 static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
1994                                     compat_ulong_t __user *data)
1995 {
1996         int ret;
1997         u32 kdata = 0;
1998
1999         if (num == 0)
2000                 return 0;
2001
2002         ret = get_user(kdata, data);
2003         if (ret)
2004                 return ret;
2005
2006         if (num < 0)
2007                 ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
2008         else
2009                 ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
2010
2011         return ret;
2012 }
2013 #endif  /* CONFIG_HAVE_HW_BREAKPOINT */
2014
2015 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
2016                         compat_ulong_t caddr, compat_ulong_t cdata)
2017 {
2018         unsigned long addr = caddr;
2019         unsigned long data = cdata;
2020         void __user *datap = compat_ptr(data);
2021         int ret;
2022
2023         switch (request) {
2024                 case PTRACE_PEEKUSR:
2025                         ret = compat_ptrace_read_user(child, addr, datap);
2026                         break;
2027
2028                 case PTRACE_POKEUSR:
2029                         ret = compat_ptrace_write_user(child, addr, data);
2030                         break;
2031
2032                 case COMPAT_PTRACE_GETREGS:
2033                         ret = copy_regset_to_user(child,
2034                                                   &user_aarch32_view,
2035                                                   REGSET_COMPAT_GPR,
2036                                                   0, sizeof(compat_elf_gregset_t),
2037                                                   datap);
2038                         break;
2039
2040                 case COMPAT_PTRACE_SETREGS:
2041                         ret = copy_regset_from_user(child,
2042                                                     &user_aarch32_view,
2043                                                     REGSET_COMPAT_GPR,
2044                                                     0, sizeof(compat_elf_gregset_t),
2045                                                     datap);
2046                         break;
2047
2048                 case COMPAT_PTRACE_GET_THREAD_AREA:
2049                         ret = put_user((compat_ulong_t)child->thread.uw.tp_value,
2050                                        (compat_ulong_t __user *)datap);
2051                         break;
2052
2053                 case COMPAT_PTRACE_SET_SYSCALL:
2054                         task_pt_regs(child)->syscallno = data;
2055                         ret = 0;
2056                         break;
2057
2058                 case COMPAT_PTRACE_GETVFPREGS:
2059                         ret = copy_regset_to_user(child,
2060                                                   &user_aarch32_view,
2061                                                   REGSET_COMPAT_VFP,
2062                                                   0, VFP_STATE_SIZE,
2063                                                   datap);
2064                         break;
2065
2066                 case COMPAT_PTRACE_SETVFPREGS:
2067                         ret = copy_regset_from_user(child,
2068                                                     &user_aarch32_view,
2069                                                     REGSET_COMPAT_VFP,
2070                                                     0, VFP_STATE_SIZE,
2071                                                     datap);
2072                         break;
2073
2074 #ifdef CONFIG_HAVE_HW_BREAKPOINT
2075                 case COMPAT_PTRACE_GETHBPREGS:
2076                         ret = compat_ptrace_gethbpregs(child, addr, datap);
2077                         break;
2078
2079                 case COMPAT_PTRACE_SETHBPREGS:
2080                         ret = compat_ptrace_sethbpregs(child, addr, datap);
2081                         break;
2082 #endif
2083
2084                 default:
2085                         ret = compat_ptrace_request(child, request, addr,
2086                                                     data);
2087                         break;
2088         }
2089
2090         return ret;
2091 }
2092 #endif /* CONFIG_COMPAT */
2093
2094 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
2095 {
2096 #ifdef CONFIG_COMPAT
2097         /*
2098          * Core dumping of 32-bit tasks or compat ptrace requests must use the
2099          * user_aarch32_view compatible with arm32. Native ptrace requests on
2100          * 32-bit children use an extended user_aarch32_ptrace_view to allow
2101          * access to the TLS register.
2102          */
2103         if (is_compat_task())
2104                 return &user_aarch32_view;
2105         else if (is_compat_thread(task_thread_info(task)))
2106                 return &user_aarch32_ptrace_view;
2107 #endif
2108         return &user_aarch64_view;
2109 }
2110
2111 long arch_ptrace(struct task_struct *child, long request,
2112                  unsigned long addr, unsigned long data)
2113 {
2114         switch (request) {
2115         case PTRACE_PEEKMTETAGS:
2116         case PTRACE_POKEMTETAGS:
2117                 return mte_ptrace_copy_tags(child, request, addr, data);
2118         }
2119
2120         return ptrace_request(child, request, addr, data);
2121 }
2122
2123 enum ptrace_syscall_dir {
2124         PTRACE_SYSCALL_ENTER = 0,
2125         PTRACE_SYSCALL_EXIT,
2126 };
2127
2128 static void report_syscall(struct pt_regs *regs, enum ptrace_syscall_dir dir)
2129 {
2130         int regno;
2131         unsigned long saved_reg;
2132
2133         /*
2134          * We have some ABI weirdness here in the way that we handle syscall
2135          * exit stops because we indicate whether or not the stop has been
2136          * signalled from syscall entry or syscall exit by clobbering a general
2137          * purpose register (ip/r12 for AArch32, x7 for AArch64) in the tracee
2138          * and restoring its old value after the stop. This means that:
2139          *
2140          * - Any writes by the tracer to this register during the stop are
2141          *   ignored/discarded.
2142          *
2143          * - The actual value of the register is not available during the stop,
2144          *   so the tracer cannot save it and restore it later.
2145          *
2146          * - Syscall stops behave differently to seccomp and pseudo-step traps
2147          *   (the latter do not nobble any registers).
2148          */
2149         regno = (is_compat_task() ? 12 : 7);
2150         saved_reg = regs->regs[regno];
2151         regs->regs[regno] = dir;
2152
2153         if (dir == PTRACE_SYSCALL_ENTER) {
2154                 if (ptrace_report_syscall_entry(regs))
2155                         forget_syscall(regs);
2156                 regs->regs[regno] = saved_reg;
2157         } else if (!test_thread_flag(TIF_SINGLESTEP)) {
2158                 ptrace_report_syscall_exit(regs, 0);
2159                 regs->regs[regno] = saved_reg;
2160         } else {
2161                 regs->regs[regno] = saved_reg;
2162
2163                 /*
2164                  * Signal a pseudo-step exception since we are stepping but
2165                  * tracer modifications to the registers may have rewound the
2166                  * state machine.
2167                  */
2168                 ptrace_report_syscall_exit(regs, 1);
2169         }
2170 }
2171
2172 int syscall_trace_enter(struct pt_regs *regs)
2173 {
2174         unsigned long flags = read_thread_flags();
2175
2176         if (flags & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE)) {
2177                 report_syscall(regs, PTRACE_SYSCALL_ENTER);
2178                 if (flags & _TIF_SYSCALL_EMU)
2179                         return NO_SYSCALL;
2180         }
2181
2182         /* Do the secure computing after ptrace; failures should be fast. */
2183         if (secure_computing() == -1)
2184                 return NO_SYSCALL;
2185
2186         if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
2187                 trace_sys_enter(regs, regs->syscallno);
2188
2189         audit_syscall_entry(regs->syscallno, regs->orig_x0, regs->regs[1],
2190                             regs->regs[2], regs->regs[3]);
2191
2192         return regs->syscallno;
2193 }
2194
2195 void syscall_trace_exit(struct pt_regs *regs)
2196 {
2197         unsigned long flags = read_thread_flags();
2198
2199         audit_syscall_exit(regs);
2200
2201         if (flags & _TIF_SYSCALL_TRACEPOINT)
2202                 trace_sys_exit(regs, syscall_get_return_value(current, regs));
2203
2204         if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP))
2205                 report_syscall(regs, PTRACE_SYSCALL_EXIT);
2206
2207         rseq_syscall(regs);
2208 }
2209
2210 /*
2211  * SPSR_ELx bits which are always architecturally RES0 per ARM DDI 0487D.a.
2212  * We permit userspace to set SSBS (AArch64 bit 12, AArch32 bit 23) which is
2213  * not described in ARM DDI 0487D.a.
2214  * We treat PAN and UAO as RES0 bits, as they are meaningless at EL0, and may
2215  * be allocated an EL0 meaning in future.
2216  * Userspace cannot use these until they have an architectural meaning.
2217  * Note that this follows the SPSR_ELx format, not the AArch32 PSR format.
2218  * We also reserve IL for the kernel; SS is handled dynamically.
2219  */
2220 #define SPSR_EL1_AARCH64_RES0_BITS \
2221         (GENMASK_ULL(63, 32) | GENMASK_ULL(27, 26) | GENMASK_ULL(23, 22) | \
2222          GENMASK_ULL(20, 13) | GENMASK_ULL(5, 5))
2223 #define SPSR_EL1_AARCH32_RES0_BITS \
2224         (GENMASK_ULL(63, 32) | GENMASK_ULL(22, 22) | GENMASK_ULL(20, 20))
2225
2226 static int valid_compat_regs(struct user_pt_regs *regs)
2227 {
2228         regs->pstate &= ~SPSR_EL1_AARCH32_RES0_BITS;
2229
2230         if (!system_supports_mixed_endian_el0()) {
2231                 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
2232                         regs->pstate |= PSR_AA32_E_BIT;
2233                 else
2234                         regs->pstate &= ~PSR_AA32_E_BIT;
2235         }
2236
2237         if (user_mode(regs) && (regs->pstate & PSR_MODE32_BIT) &&
2238             (regs->pstate & PSR_AA32_A_BIT) == 0 &&
2239             (regs->pstate & PSR_AA32_I_BIT) == 0 &&
2240             (regs->pstate & PSR_AA32_F_BIT) == 0) {
2241                 return 1;
2242         }
2243
2244         /*
2245          * Force PSR to a valid 32-bit EL0t, preserving the same bits as
2246          * arch/arm.
2247          */
2248         regs->pstate &= PSR_AA32_N_BIT | PSR_AA32_Z_BIT |
2249                         PSR_AA32_C_BIT | PSR_AA32_V_BIT |
2250                         PSR_AA32_Q_BIT | PSR_AA32_IT_MASK |
2251                         PSR_AA32_GE_MASK | PSR_AA32_E_BIT |
2252                         PSR_AA32_T_BIT;
2253         regs->pstate |= PSR_MODE32_BIT;
2254
2255         return 0;
2256 }
2257
2258 static int valid_native_regs(struct user_pt_regs *regs)
2259 {
2260         regs->pstate &= ~SPSR_EL1_AARCH64_RES0_BITS;
2261
2262         if (user_mode(regs) && !(regs->pstate & PSR_MODE32_BIT) &&
2263             (regs->pstate & PSR_D_BIT) == 0 &&
2264             (regs->pstate & PSR_A_BIT) == 0 &&
2265             (regs->pstate & PSR_I_BIT) == 0 &&
2266             (regs->pstate & PSR_F_BIT) == 0) {
2267                 return 1;
2268         }
2269
2270         /* Force PSR to a valid 64-bit EL0t */
2271         regs->pstate &= PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT;
2272
2273         return 0;
2274 }
2275
2276 /*
2277  * Are the current registers suitable for user mode? (used to maintain
2278  * security in signal handlers)
2279  */
2280 int valid_user_regs(struct user_pt_regs *regs, struct task_struct *task)
2281 {
2282         /* https://lore.kernel.org/lkml/20191118131525.GA4180@willie-the-truck */
2283         user_regs_reset_single_step(regs, task);
2284
2285         if (is_compat_thread(task_thread_info(task)))
2286                 return valid_compat_regs(regs);
2287         else
2288                 return valid_native_regs(regs);
2289 }