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
 885                         /*
 886                          * Disable traps and ensure there is SME storage but
 887                          * preserve any currently set values in ZA/ZT.
 888                          */
 889                         sme_alloc(target, false);
 890                         set_tsk_thread_flag(target, TIF_SME);
 891                         break;
 892                 default:
 893                         WARN_ON_ONCE(1);
 894                         ret = -EINVAL;
 895                         goto out;
 896                 }
 897
 898                 /*
 899                  * If we switched then invalidate any existing SVE
 900                  * state and ensure there's storage.
 901                  */
 902                 if (target->thread.svcr != old_svcr)
 903                         sve_alloc(target, true);
 904         }
 905
 906         /* Registers: FPSIMD-only case */
 907
 908         BUILD_BUG_ON(SVE_PT_FPSIMD_OFFSET != sizeof(header));
 909         if ((header.flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_FPSIMD) {
 910                 ret = __fpr_set(target, regset, pos, count, kbuf, ubuf,
 911                                 SVE_PT_FPSIMD_OFFSET);
 912                 clear_tsk_thread_flag(target, TIF_SVE);
 913                 target->thread.fp_type = FP_STATE_FPSIMD;
 914                 goto out;
 915         }
 916
 917         /*
 918          * Otherwise: no registers or full SVE case.  For backwards
 919          * compatibility reasons we treat empty flags as SVE registers.
 920          */
 921
 922         /*
 923          * If setting a different VL from the requested VL and there is
 924          * register data, the data layout will be wrong: don't even
 925          * try to set the registers in this case.
 926          */
 927         if (count && vq != sve_vq_from_vl(header.vl)) {
 928                 ret = -EIO;
 929                 goto out;
 930         }
 931
 932         sve_alloc(target, true);
 933         if (!target->thread.sve_state) {
 934                 ret = -ENOMEM;
 935                 clear_tsk_thread_flag(target, TIF_SVE);
 936                 target->thread.fp_type = FP_STATE_FPSIMD;
 937                 goto out;
 938         }
 939
 940         /*
 941          * Ensure target->thread.sve_state is up to date with target's
 942          * FPSIMD regs, so that a short copyin leaves trailing
 943          * registers unmodified.  Only enable SVE if we are
 944          * configuring normal SVE, a system with streaming SVE may not
 945          * have normal SVE.
 946          */
 947         fpsimd_sync_to_sve(target);
 948         if (type == ARM64_VEC_SVE)
 949                 set_tsk_thread_flag(target, TIF_SVE);
 950         target->thread.fp_type = FP_STATE_SVE;
 951
 952         BUILD_BUG_ON(SVE_PT_SVE_OFFSET != sizeof(header));
 953         start = SVE_PT_SVE_OFFSET;
 954         end = SVE_PT_SVE_FFR_OFFSET(vq) + SVE_PT_SVE_FFR_SIZE(vq);
 955         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 956                                  target->thread.sve_state,
 957                                  start, end);
 958         if (ret)
 959                 goto out;
 960
 961         start = end;
 962         end = SVE_PT_SVE_FPSR_OFFSET(vq);
 963         user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, start, end);
 964
 965         /*
 966          * Copy fpsr, and fpcr which must follow contiguously in
 967          * struct fpsimd_state:
 968          */
 969         start = end;
 970         end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
 971         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 972                                  &target->thread.uw.fpsimd_state.fpsr,
 973                                  start, end);
 974
 975 out:
 976         fpsimd_flush_task_state(target);
 977         return ret;
 978 }
 979
 980 static int sve_set(struct task_struct *target,
 981                    const struct user_regset *regset,
 982                    unsigned int pos, unsigned int count,
 983                    const void *kbuf, const void __user *ubuf)
 984 {
 985         if (!system_supports_sve())
 986                 return -EINVAL;
 987
 988         return sve_set_common(target, regset, pos, count, kbuf, ubuf,
 989                               ARM64_VEC_SVE);
 990 }
 991
 992 #endif /* CONFIG_ARM64_SVE */
 993
 994 #ifdef CONFIG_ARM64_SME
 995
 996 static int ssve_get(struct task_struct *target,
 997                    const struct user_regset *regset,
 998                    struct membuf to)
 999 {
1000         if (!system_supports_sme())
1001                 return -EINVAL;
1002
1003         return sve_get_common(target, regset, to, ARM64_VEC_SME);
1004 }
1005
1006 static int ssve_set(struct task_struct *target,
1007                     const struct user_regset *regset,
1008                     unsigned int pos, unsigned int count,
1009                     const void *kbuf, const void __user *ubuf)
1010 {
1011         if (!system_supports_sme())
1012                 return -EINVAL;
1013
1014         return sve_set_common(target, regset, pos, count, kbuf, ubuf,
1015                               ARM64_VEC_SME);
1016 }
1017
1018 static int za_get(struct task_struct *target,
1019                   const struct user_regset *regset,
1020                   struct membuf to)
1021 {
1022         struct user_za_header header;
1023         unsigned int vq;
1024         unsigned long start, end;
1025
1026         if (!system_supports_sme())
1027                 return -EINVAL;
1028
1029         /* Header */
1030         memset(&header, 0, sizeof(header));
1031
1032         if (test_tsk_thread_flag(target, TIF_SME_VL_INHERIT))
1033                 header.flags |= ZA_PT_VL_INHERIT;
1034
1035         header.vl = task_get_sme_vl(target);
1036         vq = sve_vq_from_vl(header.vl);
1037         header.max_vl = sme_max_vl();
1038         header.max_size = ZA_PT_SIZE(vq);
1039
1040         /* If ZA is not active there is only the header */
1041         if (thread_za_enabled(&target->thread))
1042                 header.size = ZA_PT_SIZE(vq);
1043         else
1044                 header.size = ZA_PT_ZA_OFFSET;
1045
1046         membuf_write(&to, &header, sizeof(header));
1047
1048         BUILD_BUG_ON(ZA_PT_ZA_OFFSET != sizeof(header));
1049         end = ZA_PT_ZA_OFFSET;
1050
1051         if (target == current)
1052                 fpsimd_preserve_current_state();
1053
1054         /* Any register data to include? */
1055         if (thread_za_enabled(&target->thread)) {
1056                 start = end;
1057                 end = ZA_PT_SIZE(vq);
1058                 membuf_write(&to, target->thread.sme_state, end - start);
1059         }
1060
1061         /* Zero any trailing padding */
1062         start = end;
1063         end = ALIGN(header.size, SVE_VQ_BYTES);
1064         return membuf_zero(&to, end - start);
1065 }
1066
1067 static int za_set(struct task_struct *target,
1068                   const struct user_regset *regset,
1069                   unsigned int pos, unsigned int count,
1070                   const void *kbuf, const void __user *ubuf)
1071 {
1072         int ret;
1073         struct user_za_header header;
1074         unsigned int vq;
1075         unsigned long start, end;
1076
1077         if (!system_supports_sme())
1078                 return -EINVAL;
1079
1080         /* Header */
1081         if (count < sizeof(header))
1082                 return -EINVAL;
1083         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &header,
1084                                  0, sizeof(header));
1085         if (ret)
1086                 goto out;
1087
1088         /*
1089          * All current ZA_PT_* flags are consumed by
1090          * vec_set_vector_length(), which will also validate them for
1091          * us:
1092          */
1093         ret = vec_set_vector_length(target, ARM64_VEC_SME, header.vl,
1094                 ((unsigned long)header.flags) << 16);
1095         if (ret)
1096                 goto out;
1097
1098         /* Actual VL set may be less than the user asked for: */
1099         vq = sve_vq_from_vl(task_get_sme_vl(target));
1100
1101         /* Ensure there is some SVE storage for streaming mode */
1102         if (!target->thread.sve_state) {
1103                 sve_alloc(target, false);
1104                 if (!target->thread.sve_state) {
1105                         ret = -ENOMEM;
1106                         goto out;
1107                 }
1108         }
1109
1110         /* Allocate/reinit ZA storage */
1111         sme_alloc(target, true);
1112         if (!target->thread.sme_state) {
1113                 ret = -ENOMEM;
1114                 goto out;
1115         }
1116
1117         /* If there is no data then disable ZA */
1118         if (!count) {
1119                 target->thread.svcr &= ~SVCR_ZA_MASK;
1120                 goto out;
1121         }
1122
1123         /*
1124          * If setting a different VL from the requested VL and there is
1125          * register data, the data layout will be wrong: don't even
1126          * try to set the registers in this case.
1127          */
1128         if (vq != sve_vq_from_vl(header.vl)) {
1129                 ret = -EIO;
1130                 goto out;
1131         }
1132
1133         BUILD_BUG_ON(ZA_PT_ZA_OFFSET != sizeof(header));
1134         start = ZA_PT_ZA_OFFSET;
1135         end = ZA_PT_SIZE(vq);
1136         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1137                                  target->thread.sme_state,
1138                                  start, end);
1139         if (ret)
1140                 goto out;
1141
1142         /* Mark ZA as active and let userspace use it */
1143         set_tsk_thread_flag(target, TIF_SME);
1144         target->thread.svcr |= SVCR_ZA_MASK;
1145
1146 out:
1147         fpsimd_flush_task_state(target);
1148         return ret;
1149 }
1150
1151 static int zt_get(struct task_struct *target,
1152                   const struct user_regset *regset,
1153                   struct membuf to)
1154 {
1155         if (!system_supports_sme2())
1156                 return -EINVAL;
1157
1158         /*
1159          * If PSTATE.ZA is not set then ZT will be zeroed when it is
1160          * enabled so report the current register value as zero.
1161          */
1162         if (thread_za_enabled(&target->thread))
1163                 membuf_write(&to, thread_zt_state(&target->thread),
1164                              ZT_SIG_REG_BYTES);
1165         else
1166                 membuf_zero(&to, ZT_SIG_REG_BYTES);
1167
1168         return 0;
1169 }
1170
1171 static int zt_set(struct task_struct *target,
1172                   const struct user_regset *regset,
1173                   unsigned int pos, unsigned int count,
1174                   const void *kbuf, const void __user *ubuf)
1175 {
1176         int ret;
1177
1178         if (!system_supports_sme2())
1179                 return -EINVAL;
1180
1181         /* Ensure SVE storage in case this is first use of SME */
1182         sve_alloc(target, false);
1183         if (!target->thread.sve_state)
1184                 return -ENOMEM;
1185
1186         if (!thread_za_enabled(&target->thread)) {
1187                 sme_alloc(target, true);
1188                 if (!target->thread.sme_state)
1189                         return -ENOMEM;
1190         }
1191
1192         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1193                                  thread_zt_state(&target->thread),
1194                                  0, ZT_SIG_REG_BYTES);
1195         if (ret == 0) {
1196                 target->thread.svcr |= SVCR_ZA_MASK;
1197                 set_tsk_thread_flag(target, TIF_SME);
1198         }
1199
1200         fpsimd_flush_task_state(target);
1201
1202         return ret;
1203 }
1204
1205 #endif /* CONFIG_ARM64_SME */
1206
1207 #ifdef CONFIG_ARM64_PTR_AUTH
1208 static int pac_mask_get(struct task_struct *target,
1209                         const struct user_regset *regset,
1210                         struct membuf to)
1211 {
1212         /*
1213          * The PAC bits can differ across data and instruction pointers
1214          * depending on TCR_EL1.TBID*, which we may make use of in future, so
1215          * we expose separate masks.
1216          */
1217         unsigned long mask = ptrauth_user_pac_mask();
1218         struct user_pac_mask uregs = {
1219                 .data_mask = mask,
1220                 .insn_mask = mask,
1221         };
1222
1223         if (!system_supports_address_auth())
1224                 return -EINVAL;
1225
1226         return membuf_write(&to, &uregs, sizeof(uregs));
1227 }
1228
1229 static int pac_enabled_keys_get(struct task_struct *target,
1230                                 const struct user_regset *regset,
1231                                 struct membuf to)
1232 {
1233         long enabled_keys = ptrauth_get_enabled_keys(target);
1234
1235         if (IS_ERR_VALUE(enabled_keys))
1236                 return enabled_keys;
1237
1238         return membuf_write(&to, &enabled_keys, sizeof(enabled_keys));
1239 }
1240
1241 static int pac_enabled_keys_set(struct task_struct *target,
1242                                 const struct user_regset *regset,
1243                                 unsigned int pos, unsigned int count,
1244                                 const void *kbuf, const void __user *ubuf)
1245 {
1246         int ret;
1247         long enabled_keys = ptrauth_get_enabled_keys(target);
1248
1249         if (IS_ERR_VALUE(enabled_keys))
1250                 return enabled_keys;
1251
1252         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &enabled_keys, 0,
1253                                  sizeof(long));
1254         if (ret)
1255                 return ret;
1256
1257         return ptrauth_set_enabled_keys(target, PR_PAC_ENABLED_KEYS_MASK,
1258                                         enabled_keys);
1259 }
1260
1261 #ifdef CONFIG_CHECKPOINT_RESTORE
1262 static __uint128_t pac_key_to_user(const struct ptrauth_key *key)
1263 {
1264         return (__uint128_t)key->hi << 64 | key->lo;
1265 }
1266
1267 static struct ptrauth_key pac_key_from_user(__uint128_t ukey)
1268 {
1269         struct ptrauth_key key = {
1270                 .lo = (unsigned long)ukey,
1271                 .hi = (unsigned long)(ukey >> 64),
1272         };
1273
1274         return key;
1275 }
1276
1277 static void pac_address_keys_to_user(struct user_pac_address_keys *ukeys,
1278                                      const struct ptrauth_keys_user *keys)
1279 {
1280         ukeys->apiakey = pac_key_to_user(&keys->apia);
1281         ukeys->apibkey = pac_key_to_user(&keys->apib);
1282         ukeys->apdakey = pac_key_to_user(&keys->apda);
1283         ukeys->apdbkey = pac_key_to_user(&keys->apdb);
1284 }
1285
1286 static void pac_address_keys_from_user(struct ptrauth_keys_user *keys,
1287                                        const struct user_pac_address_keys *ukeys)
1288 {
1289         keys->apia = pac_key_from_user(ukeys->apiakey);
1290         keys->apib = pac_key_from_user(ukeys->apibkey);
1291         keys->apda = pac_key_from_user(ukeys->apdakey);
1292         keys->apdb = pac_key_from_user(ukeys->apdbkey);
1293 }
1294
1295 static int pac_address_keys_get(struct task_struct *target,
1296                                 const struct user_regset *regset,
1297                                 struct membuf to)
1298 {
1299         struct ptrauth_keys_user *keys = &target->thread.keys_user;
1300         struct user_pac_address_keys user_keys;
1301
1302         if (!system_supports_address_auth())
1303                 return -EINVAL;
1304
1305         pac_address_keys_to_user(&user_keys, keys);
1306
1307         return membuf_write(&to, &user_keys, sizeof(user_keys));
1308 }
1309
1310 static int pac_address_keys_set(struct task_struct *target,
1311                                 const struct user_regset *regset,
1312                                 unsigned int pos, unsigned int count,
1313                                 const void *kbuf, const void __user *ubuf)
1314 {
1315         struct ptrauth_keys_user *keys = &target->thread.keys_user;
1316         struct user_pac_address_keys user_keys;
1317         int ret;
1318
1319         if (!system_supports_address_auth())
1320                 return -EINVAL;
1321
1322         pac_address_keys_to_user(&user_keys, keys);
1323         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1324                                  &user_keys, 0, -1);
1325         if (ret)
1326                 return ret;
1327         pac_address_keys_from_user(keys, &user_keys);
1328
1329         return 0;
1330 }
1331
1332 static void pac_generic_keys_to_user(struct user_pac_generic_keys *ukeys,
1333                                      const struct ptrauth_keys_user *keys)
1334 {
1335         ukeys->apgakey = pac_key_to_user(&keys->apga);
1336 }
1337
1338 static void pac_generic_keys_from_user(struct ptrauth_keys_user *keys,
1339                                        const struct user_pac_generic_keys *ukeys)
1340 {
1341         keys->apga = pac_key_from_user(ukeys->apgakey);
1342 }
1343
1344 static int pac_generic_keys_get(struct task_struct *target,
1345                                 const struct user_regset *regset,
1346                                 struct membuf to)
1347 {
1348         struct ptrauth_keys_user *keys = &target->thread.keys_user;
1349         struct user_pac_generic_keys user_keys;
1350
1351         if (!system_supports_generic_auth())
1352                 return -EINVAL;
1353
1354         pac_generic_keys_to_user(&user_keys, keys);
1355
1356         return membuf_write(&to, &user_keys, sizeof(user_keys));
1357 }
1358
1359 static int pac_generic_keys_set(struct task_struct *target,
1360                                 const struct user_regset *regset,
1361                                 unsigned int pos, unsigned int count,
1362                                 const void *kbuf, const void __user *ubuf)
1363 {
1364         struct ptrauth_keys_user *keys = &target->thread.keys_user;
1365         struct user_pac_generic_keys user_keys;
1366         int ret;
1367
1368         if (!system_supports_generic_auth())
1369                 return -EINVAL;
1370
1371         pac_generic_keys_to_user(&user_keys, keys);
1372         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1373                                  &user_keys, 0, -1);
1374         if (ret)
1375                 return ret;
1376         pac_generic_keys_from_user(keys, &user_keys);
1377
1378         return 0;
1379 }
1380 #endif /* CONFIG_CHECKPOINT_RESTORE */
1381 #endif /* CONFIG_ARM64_PTR_AUTH */
1382
1383 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1384 static int tagged_addr_ctrl_get(struct task_struct *target,
1385                                 const struct user_regset *regset,
1386                                 struct membuf to)
1387 {
1388         long ctrl = get_tagged_addr_ctrl(target);
1389
1390         if (IS_ERR_VALUE(ctrl))
1391                 return ctrl;
1392
1393         return membuf_write(&to, &ctrl, sizeof(ctrl));
1394 }
1395
1396 static int tagged_addr_ctrl_set(struct task_struct *target, const struct
1397                                 user_regset *regset, unsigned int pos,
1398                                 unsigned int count, const void *kbuf, const
1399                                 void __user *ubuf)
1400 {
1401         int ret;
1402         long ctrl;
1403
1404         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl, 0, -1);
1405         if (ret)
1406                 return ret;
1407
1408         return set_tagged_addr_ctrl(target, ctrl);
1409 }
1410 #endif
1411
1412 enum aarch64_regset {
1413         REGSET_GPR,
1414         REGSET_FPR,
1415         REGSET_TLS,
1416 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1417         REGSET_HW_BREAK,
1418         REGSET_HW_WATCH,
1419 #endif
1420         REGSET_SYSTEM_CALL,
1421 #ifdef CONFIG_ARM64_SVE
1422         REGSET_SVE,
1423 #endif
1424 #ifdef CONFIG_ARM64_SME
1425         REGSET_SSVE,
1426         REGSET_ZA,
1427         REGSET_ZT,
1428 #endif
1429 #ifdef CONFIG_ARM64_PTR_AUTH
1430         REGSET_PAC_MASK,
1431         REGSET_PAC_ENABLED_KEYS,
1432 #ifdef CONFIG_CHECKPOINT_RESTORE
1433         REGSET_PACA_KEYS,
1434         REGSET_PACG_KEYS,
1435 #endif
1436 #endif
1437 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1438         REGSET_TAGGED_ADDR_CTRL,
1439 #endif
1440 };
1441
1442 static const struct user_regset aarch64_regsets[] = {
1443         [REGSET_GPR] = {
1444                 .core_note_type = NT_PRSTATUS,
1445                 .n = sizeof(struct user_pt_regs) / sizeof(u64),
1446                 .size = sizeof(u64),
1447                 .align = sizeof(u64),
1448                 .regset_get = gpr_get,
1449                 .set = gpr_set
1450         },
1451         [REGSET_FPR] = {
1452                 .core_note_type = NT_PRFPREG,
1453                 .n = sizeof(struct user_fpsimd_state) / sizeof(u32),
1454                 /*
1455                  * We pretend we have 32-bit registers because the fpsr and
1456                  * fpcr are 32-bits wide.
1457                  */
1458                 .size = sizeof(u32),
1459                 .align = sizeof(u32),
1460                 .active = fpr_active,
1461                 .regset_get = fpr_get,
1462                 .set = fpr_set
1463         },
1464         [REGSET_TLS] = {
1465                 .core_note_type = NT_ARM_TLS,
1466                 .n = 2,
1467                 .size = sizeof(void *),
1468                 .align = sizeof(void *),
1469                 .regset_get = tls_get,
1470                 .set = tls_set,
1471         },
1472 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1473         [REGSET_HW_BREAK] = {
1474                 .core_note_type = NT_ARM_HW_BREAK,
1475                 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1476                 .size = sizeof(u32),
1477                 .align = sizeof(u32),
1478                 .regset_get = hw_break_get,
1479                 .set = hw_break_set,
1480         },
1481         [REGSET_HW_WATCH] = {
1482                 .core_note_type = NT_ARM_HW_WATCH,
1483                 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1484                 .size = sizeof(u32),
1485                 .align = sizeof(u32),
1486                 .regset_get = hw_break_get,
1487                 .set = hw_break_set,
1488         },
1489 #endif
1490         [REGSET_SYSTEM_CALL] = {
1491                 .core_note_type = NT_ARM_SYSTEM_CALL,
1492                 .n = 1,
1493                 .size = sizeof(int),
1494                 .align = sizeof(int),
1495                 .regset_get = system_call_get,
1496                 .set = system_call_set,
1497         },
1498 #ifdef CONFIG_ARM64_SVE
1499         [REGSET_SVE] = { /* Scalable Vector Extension */
1500                 .core_note_type = NT_ARM_SVE,
1501                 .n = DIV_ROUND_UP(SVE_PT_SIZE(SVE_VQ_MAX, SVE_PT_REGS_SVE),
1502                                   SVE_VQ_BYTES),
1503                 .size = SVE_VQ_BYTES,
1504                 .align = SVE_VQ_BYTES,
1505                 .regset_get = sve_get,
1506                 .set = sve_set,
1507         },
1508 #endif
1509 #ifdef CONFIG_ARM64_SME
1510         [REGSET_SSVE] = { /* Streaming mode SVE */
1511                 .core_note_type = NT_ARM_SSVE,
1512                 .n = DIV_ROUND_UP(SVE_PT_SIZE(SME_VQ_MAX, SVE_PT_REGS_SVE),
1513                                   SVE_VQ_BYTES),
1514                 .size = SVE_VQ_BYTES,
1515                 .align = SVE_VQ_BYTES,
1516                 .regset_get = ssve_get,
1517                 .set = ssve_set,
1518         },
1519         [REGSET_ZA] = { /* SME ZA */
1520                 .core_note_type = NT_ARM_ZA,
1521                 /*
1522                  * ZA is a single register but it's variably sized and
1523                  * the ptrace core requires that the size of any data
1524                  * be an exact multiple of the configured register
1525                  * size so report as though we had SVE_VQ_BYTES
1526                  * registers. These values aren't exposed to
1527                  * userspace.
1528                  */
1529                 .n = DIV_ROUND_UP(ZA_PT_SIZE(SME_VQ_MAX), SVE_VQ_BYTES),
1530                 .size = SVE_VQ_BYTES,
1531                 .align = SVE_VQ_BYTES,
1532                 .regset_get = za_get,
1533                 .set = za_set,
1534         },
1535         [REGSET_ZT] = { /* SME ZT */
1536                 .core_note_type = NT_ARM_ZT,
1537                 .n = 1,
1538                 .size = ZT_SIG_REG_BYTES,
1539                 .align = sizeof(u64),
1540                 .regset_get = zt_get,
1541                 .set = zt_set,
1542         },
1543 #endif
1544 #ifdef CONFIG_ARM64_PTR_AUTH
1545         [REGSET_PAC_MASK] = {
1546                 .core_note_type = NT_ARM_PAC_MASK,
1547                 .n = sizeof(struct user_pac_mask) / sizeof(u64),
1548                 .size = sizeof(u64),
1549                 .align = sizeof(u64),
1550                 .regset_get = pac_mask_get,
1551                 /* this cannot be set dynamically */
1552         },
1553         [REGSET_PAC_ENABLED_KEYS] = {
1554                 .core_note_type = NT_ARM_PAC_ENABLED_KEYS,
1555                 .n = 1,
1556                 .size = sizeof(long),
1557                 .align = sizeof(long),
1558                 .regset_get = pac_enabled_keys_get,
1559                 .set = pac_enabled_keys_set,
1560         },
1561 #ifdef CONFIG_CHECKPOINT_RESTORE
1562         [REGSET_PACA_KEYS] = {
1563                 .core_note_type = NT_ARM_PACA_KEYS,
1564                 .n = sizeof(struct user_pac_address_keys) / sizeof(__uint128_t),
1565                 .size = sizeof(__uint128_t),
1566                 .align = sizeof(__uint128_t),
1567                 .regset_get = pac_address_keys_get,
1568                 .set = pac_address_keys_set,
1569         },
1570         [REGSET_PACG_KEYS] = {
1571                 .core_note_type = NT_ARM_PACG_KEYS,
1572                 .n = sizeof(struct user_pac_generic_keys) / sizeof(__uint128_t),
1573                 .size = sizeof(__uint128_t),
1574                 .align = sizeof(__uint128_t),
1575                 .regset_get = pac_generic_keys_get,
1576                 .set = pac_generic_keys_set,
1577         },
1578 #endif
1579 #endif
1580 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1581         [REGSET_TAGGED_ADDR_CTRL] = {
1582                 .core_note_type = NT_ARM_TAGGED_ADDR_CTRL,
1583                 .n = 1,
1584                 .size = sizeof(long),
1585                 .align = sizeof(long),
1586                 .regset_get = tagged_addr_ctrl_get,
1587                 .set = tagged_addr_ctrl_set,
1588         },
1589 #endif
1590 };
1591
1592 static const struct user_regset_view user_aarch64_view = {
1593         .name = "aarch64", .e_machine = EM_AARCH64,
1594         .regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
1595 };
1596
1597 #ifdef CONFIG_COMPAT
1598 enum compat_regset {
1599         REGSET_COMPAT_GPR,
1600         REGSET_COMPAT_VFP,
1601 };
1602
1603 static inline compat_ulong_t compat_get_user_reg(struct task_struct *task, int idx)
1604 {
1605         struct pt_regs *regs = task_pt_regs(task);
1606
1607         switch (idx) {
1608         case 15:
1609                 return regs->pc;
1610         case 16:
1611                 return pstate_to_compat_psr(regs->pstate);
1612         case 17:
1613                 return regs->orig_x0;
1614         default:
1615                 return regs->regs[idx];
1616         }
1617 }
1618
1619 static int compat_gpr_get(struct task_struct *target,
1620                           const struct user_regset *regset,
1621                           struct membuf to)
1622 {
1623         int i = 0;
1624
1625         while (to.left)
1626                 membuf_store(&to, compat_get_user_reg(target, i++));
1627         return 0;
1628 }
1629
1630 static int compat_gpr_set(struct task_struct *target,
1631                           const struct user_regset *regset,
1632                           unsigned int pos, unsigned int count,
1633                           const void *kbuf, const void __user *ubuf)
1634 {
1635         struct pt_regs newregs;
1636         int ret = 0;
1637         unsigned int i, start, num_regs;
1638
1639         /* Calculate the number of AArch32 registers contained in count */
1640         num_regs = count / regset->size;
1641
1642         /* Convert pos into an register number */
1643         start = pos / regset->size;
1644
1645         if (start + num_regs > regset->n)
1646                 return -EIO;
1647
1648         newregs = *task_pt_regs(target);
1649
1650         for (i = 0; i < num_regs; ++i) {
1651                 unsigned int idx = start + i;
1652                 compat_ulong_t reg;
1653
1654                 if (kbuf) {
1655                         memcpy(&reg, kbuf, sizeof(reg));
1656                         kbuf += sizeof(reg);
1657                 } else {
1658                         ret = copy_from_user(&reg, ubuf, sizeof(reg));
1659                         if (ret) {
1660                                 ret = -EFAULT;
1661                                 break;
1662                         }
1663
1664                         ubuf += sizeof(reg);
1665                 }
1666
1667                 switch (idx) {
1668                 case 15:
1669                         newregs.pc = reg;
1670                         break;
1671                 case 16:
1672                         reg = compat_psr_to_pstate(reg);
1673                         newregs.pstate = reg;
1674                         break;
1675                 case 17:
1676                         newregs.orig_x0 = reg;
1677                         break;
1678                 default:
1679                         newregs.regs[idx] = reg;
1680                 }
1681
1682         }
1683
1684         if (valid_user_regs(&newregs.user_regs, target))
1685                 *task_pt_regs(target) = newregs;
1686         else
1687                 ret = -EINVAL;
1688
1689         return ret;
1690 }
1691
1692 static int compat_vfp_get(struct task_struct *target,
1693                           const struct user_regset *regset,
1694                           struct membuf to)
1695 {
1696         struct user_fpsimd_state *uregs;
1697         compat_ulong_t fpscr;
1698
1699         if (!system_supports_fpsimd())
1700                 return -EINVAL;
1701
1702         uregs = &target->thread.uw.fpsimd_state;
1703
1704         if (target == current)
1705                 fpsimd_preserve_current_state();
1706
1707         /*
1708          * The VFP registers are packed into the fpsimd_state, so they all sit
1709          * nicely together for us. We just need to create the fpscr separately.
1710          */
1711         membuf_write(&to, uregs, VFP_STATE_SIZE - sizeof(compat_ulong_t));
1712         fpscr = (uregs->fpsr & VFP_FPSCR_STAT_MASK) |
1713                 (uregs->fpcr & VFP_FPSCR_CTRL_MASK);
1714         return membuf_store(&to, fpscr);
1715 }
1716
1717 static int compat_vfp_set(struct task_struct *target,
1718                           const struct user_regset *regset,
1719                           unsigned int pos, unsigned int count,
1720                           const void *kbuf, const void __user *ubuf)
1721 {
1722         struct user_fpsimd_state *uregs;
1723         compat_ulong_t fpscr;
1724         int ret, vregs_end_pos;
1725
1726         if (!system_supports_fpsimd())
1727                 return -EINVAL;
1728
1729         uregs = &target->thread.uw.fpsimd_state;
1730
1731         vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t);
1732         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
1733                                  vregs_end_pos);
1734
1735         if (count && !ret) {
1736                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpscr,
1737                                          vregs_end_pos, VFP_STATE_SIZE);
1738                 if (!ret) {
1739                         uregs->fpsr = fpscr & VFP_FPSCR_STAT_MASK;
1740                         uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
1741                 }
1742         }
1743
1744         fpsimd_flush_task_state(target);
1745         return ret;
1746 }
1747
1748 static int compat_tls_get(struct task_struct *target,
1749                           const struct user_regset *regset,
1750                           struct membuf to)
1751 {
1752         return membuf_store(&to, (compat_ulong_t)target->thread.uw.tp_value);
1753 }
1754
1755 static int compat_tls_set(struct task_struct *target,
1756                           const struct user_regset *regset, unsigned int pos,
1757                           unsigned int count, const void *kbuf,
1758                           const void __user *ubuf)
1759 {
1760         int ret;
1761         compat_ulong_t tls = target->thread.uw.tp_value;
1762
1763         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
1764         if (ret)
1765                 return ret;
1766
1767         target->thread.uw.tp_value = tls;
1768         return ret;
1769 }
1770
1771 static const struct user_regset aarch32_regsets[] = {
1772         [REGSET_COMPAT_GPR] = {
1773                 .core_note_type = NT_PRSTATUS,
1774                 .n = COMPAT_ELF_NGREG,
1775                 .size = sizeof(compat_elf_greg_t),
1776                 .align = sizeof(compat_elf_greg_t),
1777                 .regset_get = compat_gpr_get,
1778                 .set = compat_gpr_set
1779         },
1780         [REGSET_COMPAT_VFP] = {
1781                 .core_note_type = NT_ARM_VFP,
1782                 .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
1783                 .size = sizeof(compat_ulong_t),
1784                 .align = sizeof(compat_ulong_t),
1785                 .active = fpr_active,
1786                 .regset_get = compat_vfp_get,
1787                 .set = compat_vfp_set
1788         },
1789 };
1790
1791 static const struct user_regset_view user_aarch32_view = {
1792         .name = "aarch32", .e_machine = EM_ARM,
1793         .regsets = aarch32_regsets, .n = ARRAY_SIZE(aarch32_regsets)
1794 };
1795
1796 static const struct user_regset aarch32_ptrace_regsets[] = {
1797         [REGSET_GPR] = {
1798                 .core_note_type = NT_PRSTATUS,
1799                 .n = COMPAT_ELF_NGREG,
1800                 .size = sizeof(compat_elf_greg_t),
1801                 .align = sizeof(compat_elf_greg_t),
1802                 .regset_get = compat_gpr_get,
1803                 .set = compat_gpr_set
1804         },
1805         [REGSET_FPR] = {
1806                 .core_note_type = NT_ARM_VFP,
1807                 .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
1808                 .size = sizeof(compat_ulong_t),
1809                 .align = sizeof(compat_ulong_t),
1810                 .regset_get = compat_vfp_get,
1811                 .set = compat_vfp_set
1812         },
1813         [REGSET_TLS] = {
1814                 .core_note_type = NT_ARM_TLS,
1815                 .n = 1,
1816                 .size = sizeof(compat_ulong_t),
1817                 .align = sizeof(compat_ulong_t),
1818                 .regset_get = compat_tls_get,
1819                 .set = compat_tls_set,
1820         },
1821 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1822         [REGSET_HW_BREAK] = {
1823                 .core_note_type = NT_ARM_HW_BREAK,
1824                 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1825                 .size = sizeof(u32),
1826                 .align = sizeof(u32),
1827                 .regset_get = hw_break_get,
1828                 .set = hw_break_set,
1829         },
1830         [REGSET_HW_WATCH] = {
1831                 .core_note_type = NT_ARM_HW_WATCH,
1832                 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1833                 .size = sizeof(u32),
1834                 .align = sizeof(u32),
1835                 .regset_get = hw_break_get,
1836                 .set = hw_break_set,
1837         },
1838 #endif
1839         [REGSET_SYSTEM_CALL] = {
1840                 .core_note_type = NT_ARM_SYSTEM_CALL,
1841                 .n = 1,
1842                 .size = sizeof(int),
1843                 .align = sizeof(int),
1844                 .regset_get = system_call_get,
1845                 .set = system_call_set,
1846         },
1847 };
1848
1849 static const struct user_regset_view user_aarch32_ptrace_view = {
1850         .name = "aarch32", .e_machine = EM_ARM,
1851         .regsets = aarch32_ptrace_regsets, .n = ARRAY_SIZE(aarch32_ptrace_regsets)
1852 };
1853
1854 static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
1855                                    compat_ulong_t __user *ret)
1856 {
1857         compat_ulong_t tmp;
1858
1859         if (off & 3)
1860                 return -EIO;
1861
1862         if (off == COMPAT_PT_TEXT_ADDR)
1863                 tmp = tsk->mm->start_code;
1864         else if (off == COMPAT_PT_DATA_ADDR)
1865                 tmp = tsk->mm->start_data;
1866         else if (off == COMPAT_PT_TEXT_END_ADDR)
1867                 tmp = tsk->mm->end_code;
1868         else if (off < sizeof(compat_elf_gregset_t))
1869                 tmp = compat_get_user_reg(tsk, off >> 2);
1870         else if (off >= COMPAT_USER_SZ)
1871                 return -EIO;
1872         else
1873                 tmp = 0;
1874
1875         return put_user(tmp, ret);
1876 }
1877
1878 static int compat_ptrace_write_user(struct task_struct *tsk, compat_ulong_t off,
1879                                     compat_ulong_t val)
1880 {
1881         struct pt_regs newregs = *task_pt_regs(tsk);
1882         unsigned int idx = off / 4;
1883
1884         if (off & 3 || off >= COMPAT_USER_SZ)
1885                 return -EIO;
1886
1887         if (off >= sizeof(compat_elf_gregset_t))
1888                 return 0;
1889
1890         switch (idx) {
1891         case 15:
1892                 newregs.pc = val;
1893                 break;
1894         case 16:
1895                 newregs.pstate = compat_psr_to_pstate(val);
1896                 break;
1897         case 17:
1898                 newregs.orig_x0 = val;
1899                 break;
1900         default:
1901                 newregs.regs[idx] = val;
1902         }
1903
1904         if (!valid_user_regs(&newregs.user_regs, tsk))
1905                 return -EINVAL;
1906
1907         *task_pt_regs(tsk) = newregs;
1908         return 0;
1909 }
1910
1911 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1912
1913 /*
1914  * Convert a virtual register number into an index for a thread_info
1915  * breakpoint array. Breakpoints are identified using positive numbers
1916  * whilst watchpoints are negative. The registers are laid out as pairs
1917  * of (address, control), each pair mapping to a unique hw_breakpoint struct.
1918  * Register 0 is reserved for describing resource information.
1919  */
1920 static int compat_ptrace_hbp_num_to_idx(compat_long_t num)
1921 {
1922         return (abs(num) - 1) >> 1;
1923 }
1924
1925 static int compat_ptrace_hbp_get_resource_info(u32 *kdata)
1926 {
1927         u8 num_brps, num_wrps, debug_arch, wp_len;
1928         u32 reg = 0;
1929
1930         num_brps        = hw_breakpoint_slots(TYPE_INST);
1931         num_wrps        = hw_breakpoint_slots(TYPE_DATA);
1932
1933         debug_arch      = debug_monitors_arch();
1934         wp_len          = 8;
1935         reg             |= debug_arch;
1936         reg             <<= 8;
1937         reg             |= wp_len;
1938         reg             <<= 8;
1939         reg             |= num_wrps;
1940         reg             <<= 8;
1941         reg             |= num_brps;
1942
1943         *kdata = reg;
1944         return 0;
1945 }
1946
1947 static int compat_ptrace_hbp_get(unsigned int note_type,
1948                                  struct task_struct *tsk,
1949                                  compat_long_t num,
1950                                  u32 *kdata)
1951 {
1952         u64 addr = 0;
1953         u32 ctrl = 0;
1954
1955         int err, idx = compat_ptrace_hbp_num_to_idx(num);
1956
1957         if (num & 1) {
1958                 err = ptrace_hbp_get_addr(note_type, tsk, idx, &addr);
1959                 *kdata = (u32)addr;
1960         } else {
1961                 err = ptrace_hbp_get_ctrl(note_type, tsk, idx, &ctrl);
1962                 *kdata = ctrl;
1963         }
1964
1965         return err;
1966 }
1967
1968 static int compat_ptrace_hbp_set(unsigned int note_type,
1969                                  struct task_struct *tsk,
1970                                  compat_long_t num,
1971                                  u32 *kdata)
1972 {
1973         u64 addr;
1974         u32 ctrl;
1975
1976         int err, idx = compat_ptrace_hbp_num_to_idx(num);
1977
1978         if (num & 1) {
1979                 addr = *kdata;
1980                 err = ptrace_hbp_set_addr(note_type, tsk, idx, addr);
1981         } else {
1982                 ctrl = *kdata;
1983                 err = ptrace_hbp_set_ctrl(note_type, tsk, idx, ctrl);
1984         }
1985
1986         return err;
1987 }
1988
1989 static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
1990                                     compat_ulong_t __user *data)
1991 {
1992         int ret;
1993         u32 kdata;
1994
1995         /* Watchpoint */
1996         if (num < 0) {
1997                 ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
1998         /* Resource info */
1999         } else if (num == 0) {
2000                 ret = compat_ptrace_hbp_get_resource_info(&kdata);
2001         /* Breakpoint */
2002         } else {
2003                 ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
2004         }
2005
2006         if (!ret)
2007                 ret = put_user(kdata, data);
2008
2009         return ret;
2010 }
2011
2012 static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
2013                                     compat_ulong_t __user *data)
2014 {
2015         int ret;
2016         u32 kdata = 0;
2017
2018         if (num == 0)
2019                 return 0;
2020
2021         ret = get_user(kdata, data);
2022         if (ret)
2023                 return ret;
2024
2025         if (num < 0)
2026                 ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
2027         else
2028                 ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
2029
2030         return ret;
2031 }
2032 #endif  /* CONFIG_HAVE_HW_BREAKPOINT */
2033
2034 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
2035                         compat_ulong_t caddr, compat_ulong_t cdata)
2036 {
2037         unsigned long addr = caddr;
2038         unsigned long data = cdata;
2039         void __user *datap = compat_ptr(data);
2040         int ret;
2041
2042         switch (request) {
2043                 case PTRACE_PEEKUSR:
2044                         ret = compat_ptrace_read_user(child, addr, datap);
2045                         break;
2046
2047                 case PTRACE_POKEUSR:
2048                         ret = compat_ptrace_write_user(child, addr, data);
2049                         break;
2050
2051                 case COMPAT_PTRACE_GETREGS:
2052                         ret = copy_regset_to_user(child,
2053                                                   &user_aarch32_view,
2054                                                   REGSET_COMPAT_GPR,
2055                                                   0, sizeof(compat_elf_gregset_t),
2056                                                   datap);
2057                         break;
2058
2059                 case COMPAT_PTRACE_SETREGS:
2060                         ret = copy_regset_from_user(child,
2061                                                     &user_aarch32_view,
2062                                                     REGSET_COMPAT_GPR,
2063                                                     0, sizeof(compat_elf_gregset_t),
2064                                                     datap);
2065                         break;
2066
2067                 case COMPAT_PTRACE_GET_THREAD_AREA:
2068                         ret = put_user((compat_ulong_t)child->thread.uw.tp_value,
2069                                        (compat_ulong_t __user *)datap);
2070                         break;
2071
2072                 case COMPAT_PTRACE_SET_SYSCALL:
2073                         task_pt_regs(child)->syscallno = data;
2074                         ret = 0;
2075                         break;
2076
2077                 case COMPAT_PTRACE_GETVFPREGS:
2078                         ret = copy_regset_to_user(child,
2079                                                   &user_aarch32_view,
2080                                                   REGSET_COMPAT_VFP,
2081                                                   0, VFP_STATE_SIZE,
2082                                                   datap);
2083                         break;
2084
2085                 case COMPAT_PTRACE_SETVFPREGS:
2086                         ret = copy_regset_from_user(child,
2087                                                     &user_aarch32_view,
2088                                                     REGSET_COMPAT_VFP,
2089                                                     0, VFP_STATE_SIZE,
2090                                                     datap);
2091                         break;
2092
2093 #ifdef CONFIG_HAVE_HW_BREAKPOINT
2094                 case COMPAT_PTRACE_GETHBPREGS:
2095                         ret = compat_ptrace_gethbpregs(child, addr, datap);
2096                         break;
2097
2098                 case COMPAT_PTRACE_SETHBPREGS:
2099                         ret = compat_ptrace_sethbpregs(child, addr, datap);
2100                         break;
2101 #endif
2102
2103                 default:
2104                         ret = compat_ptrace_request(child, request, addr,
2105                                                     data);
2106                         break;
2107         }
2108
2109         return ret;
2110 }
2111 #endif /* CONFIG_COMPAT */
2112
2113 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
2114 {
2115 #ifdef CONFIG_COMPAT
2116         /*
2117          * Core dumping of 32-bit tasks or compat ptrace requests must use the
2118          * user_aarch32_view compatible with arm32. Native ptrace requests on
2119          * 32-bit children use an extended user_aarch32_ptrace_view to allow
2120          * access to the TLS register.
2121          */
2122         if (is_compat_task())
2123                 return &user_aarch32_view;
2124         else if (is_compat_thread(task_thread_info(task)))
2125                 return &user_aarch32_ptrace_view;
2126 #endif
2127         return &user_aarch64_view;
2128 }
2129
2130 long arch_ptrace(struct task_struct *child, long request,
2131                  unsigned long addr, unsigned long data)
2132 {
2133         switch (request) {
2134         case PTRACE_PEEKMTETAGS:
2135         case PTRACE_POKEMTETAGS:
2136                 return mte_ptrace_copy_tags(child, request, addr, data);
2137         }
2138
2139         return ptrace_request(child, request, addr, data);
2140 }
2141
2142 enum ptrace_syscall_dir {
2143         PTRACE_SYSCALL_ENTER = 0,
2144         PTRACE_SYSCALL_EXIT,
2145 };
2146
2147 static void report_syscall(struct pt_regs *regs, enum ptrace_syscall_dir dir)
2148 {
2149         int regno;
2150         unsigned long saved_reg;
2151
2152         /*
2153          * We have some ABI weirdness here in the way that we handle syscall
2154          * exit stops because we indicate whether or not the stop has been
2155          * signalled from syscall entry or syscall exit by clobbering a general
2156          * purpose register (ip/r12 for AArch32, x7 for AArch64) in the tracee
2157          * and restoring its old value after the stop. This means that:
2158          *
2159          * - Any writes by the tracer to this register during the stop are
2160          *   ignored/discarded.
2161          *
2162          * - The actual value of the register is not available during the stop,
2163          *   so the tracer cannot save it and restore it later.
2164          *
2165          * - Syscall stops behave differently to seccomp and pseudo-step traps
2166          *   (the latter do not nobble any registers).
2167          */
2168         regno = (is_compat_task() ? 12 : 7);
2169         saved_reg = regs->regs[regno];
2170         regs->regs[regno] = dir;
2171
2172         if (dir == PTRACE_SYSCALL_ENTER) {
2173                 if (ptrace_report_syscall_entry(regs))
2174                         forget_syscall(regs);
2175                 regs->regs[regno] = saved_reg;
2176         } else if (!test_thread_flag(TIF_SINGLESTEP)) {
2177                 ptrace_report_syscall_exit(regs, 0);
2178                 regs->regs[regno] = saved_reg;
2179         } else {
2180                 regs->regs[regno] = saved_reg;
2181
2182                 /*
2183                  * Signal a pseudo-step exception since we are stepping but
2184                  * tracer modifications to the registers may have rewound the
2185                  * state machine.
2186                  */
2187                 ptrace_report_syscall_exit(regs, 1);
2188         }
2189 }
2190
2191 int syscall_trace_enter(struct pt_regs *regs)
2192 {
2193         unsigned long flags = read_thread_flags();
2194
2195         if (flags & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE)) {
2196                 report_syscall(regs, PTRACE_SYSCALL_ENTER);
2197                 if (flags & _TIF_SYSCALL_EMU)
2198                         return NO_SYSCALL;
2199         }
2200
2201         /* Do the secure computing after ptrace; failures should be fast. */
2202         if (secure_computing() == -1)
2203                 return NO_SYSCALL;
2204
2205         if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
2206                 trace_sys_enter(regs, regs->syscallno);
2207
2208         audit_syscall_entry(regs->syscallno, regs->orig_x0, regs->regs[1],
2209                             regs->regs[2], regs->regs[3]);
2210
2211         return regs->syscallno;
2212 }
2213
2214 void syscall_trace_exit(struct pt_regs *regs)
2215 {
2216         unsigned long flags = read_thread_flags();
2217
2218         audit_syscall_exit(regs);
2219
2220         if (flags & _TIF_SYSCALL_TRACEPOINT)
2221                 trace_sys_exit(regs, syscall_get_return_value(current, regs));
2222
2223         if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP))
2224                 report_syscall(regs, PTRACE_SYSCALL_EXIT);
2225
2226         rseq_syscall(regs);
2227 }
2228
2229 /*
2230  * SPSR_ELx bits which are always architecturally RES0 per ARM DDI 0487D.a.
2231  * We permit userspace to set SSBS (AArch64 bit 12, AArch32 bit 23) which is
2232  * not described in ARM DDI 0487D.a.
2233  * We treat PAN and UAO as RES0 bits, as they are meaningless at EL0, and may
2234  * be allocated an EL0 meaning in future.
2235  * Userspace cannot use these until they have an architectural meaning.
2236  * Note that this follows the SPSR_ELx format, not the AArch32 PSR format.
2237  * We also reserve IL for the kernel; SS is handled dynamically.
2238  */
2239 #define SPSR_EL1_AARCH64_RES0_BITS \
2240         (GENMASK_ULL(63, 32) | GENMASK_ULL(27, 26) | GENMASK_ULL(23, 22) | \
2241          GENMASK_ULL(20, 13) | GENMASK_ULL(5, 5))
2242 #define SPSR_EL1_AARCH32_RES0_BITS \
2243         (GENMASK_ULL(63, 32) | GENMASK_ULL(22, 22) | GENMASK_ULL(20, 20))
2244
2245 static int valid_compat_regs(struct user_pt_regs *regs)
2246 {
2247         regs->pstate &= ~SPSR_EL1_AARCH32_RES0_BITS;
2248
2249         if (!system_supports_mixed_endian_el0()) {
2250                 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
2251                         regs->pstate |= PSR_AA32_E_BIT;
2252                 else
2253                         regs->pstate &= ~PSR_AA32_E_BIT;
2254         }
2255
2256         if (user_mode(regs) && (regs->pstate & PSR_MODE32_BIT) &&
2257             (regs->pstate & PSR_AA32_A_BIT) == 0 &&
2258             (regs->pstate & PSR_AA32_I_BIT) == 0 &&
2259             (regs->pstate & PSR_AA32_F_BIT) == 0) {
2260                 return 1;
2261         }
2262
2263         /*
2264          * Force PSR to a valid 32-bit EL0t, preserving the same bits as
2265          * arch/arm.
2266          */
2267         regs->pstate &= PSR_AA32_N_BIT | PSR_AA32_Z_BIT |
2268                         PSR_AA32_C_BIT | PSR_AA32_V_BIT |
2269                         PSR_AA32_Q_BIT | PSR_AA32_IT_MASK |
2270                         PSR_AA32_GE_MASK | PSR_AA32_E_BIT |
2271                         PSR_AA32_T_BIT;
2272         regs->pstate |= PSR_MODE32_BIT;
2273
2274         return 0;
2275 }
2276
2277 static int valid_native_regs(struct user_pt_regs *regs)
2278 {
2279         regs->pstate &= ~SPSR_EL1_AARCH64_RES0_BITS;
2280
2281         if (user_mode(regs) && !(regs->pstate & PSR_MODE32_BIT) &&
2282             (regs->pstate & PSR_D_BIT) == 0 &&
2283             (regs->pstate & PSR_A_BIT) == 0 &&
2284             (regs->pstate & PSR_I_BIT) == 0 &&
2285             (regs->pstate & PSR_F_BIT) == 0) {
2286                 return 1;
2287         }
2288
2289         /* Force PSR to a valid 64-bit EL0t */
2290         regs->pstate &= PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT;
2291
2292         return 0;
2293 }
2294
2295 /*
2296  * Are the current registers suitable for user mode? (used to maintain
2297  * security in signal handlers)
2298  */
2299 int valid_user_regs(struct user_pt_regs *regs, struct task_struct *task)
2300 {
2301         /* https://lore.kernel.org/lkml/20191118131525.GA4180@willie-the-truck */
2302         user_regs_reset_single_step(regs, task);
2303
2304         if (is_compat_thread(task_thread_info(task)))
2305                 return valid_compat_regs(regs);
2306         else
2307                 return valid_native_regs(regs);
2308 }