arch/sparc/kernel/signal32.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*  arch/sparc64/kernel/signal32.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   6  *  Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
   7  *  Copyright (C) 1997 Eddie C. Dost   (ecd@skynet.be)
   8  *  Copyright (C) 1997,1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
   9  */
  10
  11 #include <linux/sched.h>
  12 #include <linux/kernel.h>
  13 #include <linux/signal.h>
  14 #include <linux/errno.h>
  15 #include <linux/wait.h>
  16 #include <linux/ptrace.h>
  17 #include <linux/unistd.h>
  18 #include <linux/mm.h>
  19 #include <linux/tty.h>
  20 #include <linux/binfmts.h>
  21 #include <linux/compat.h>
  22 #include <linux/bitops.h>
  23 #include <linux/tracehook.h>
  24
  25 #include <linux/uaccess.h>
  26 #include <asm/ptrace.h>
  27 #include <asm/psrcompat.h>
  28 #include <asm/fpumacro.h>
  29 #include <asm/visasm.h>
  30 #include <asm/compat_signal.h>
  31 #include <asm/switch_to.h>
  32
  33 #include "sigutil.h"
  34 #include "kernel.h"
  35
  36 /* This magic should be in g_upper[0] for all upper parts
  37  * to be valid.
  38  */
  39 #define SIGINFO_EXTRA_V8PLUS_MAGIC      0x130e269
  40 typedef struct {
  41         unsigned int g_upper[8];
  42         unsigned int o_upper[8];
  43         unsigned int asi;
  44 } siginfo_extra_v8plus_t;
  45
  46 struct signal_frame32 {
  47         struct sparc_stackf32   ss;
  48         __siginfo32_t           info;
  49         /* __siginfo_fpu_t * */ u32 fpu_save;
  50         unsigned int            insns[2];
  51         unsigned int            extramask[_COMPAT_NSIG_WORDS - 1];
  52         unsigned int            extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
  53         /* Only valid if (info.si_regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
  54         siginfo_extra_v8plus_t  v8plus;
  55         /* __siginfo_rwin_t * */u32 rwin_save;
  56 } __attribute__((aligned(8)));
  57
  58 struct rt_signal_frame32 {
  59         struct sparc_stackf32   ss;
  60         compat_siginfo_t        info;
  61         struct pt_regs32        regs;
  62         compat_sigset_t         mask;
  63         /* __siginfo_fpu_t * */ u32 fpu_save;
  64         unsigned int            insns[2];
  65         compat_stack_t          stack;
  66         unsigned int            extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
  67         /* Only valid if (regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
  68         siginfo_extra_v8plus_t  v8plus;
  69         /* __siginfo_rwin_t * */u32 rwin_save;
  70 } __attribute__((aligned(8)));
  71
  72 /* Checks if the fp is valid.  We always build signal frames which are
  73  * 16-byte aligned, therefore we can always enforce that the restore
  74  * frame has that property as well.
  75  */
  76 static bool invalid_frame_pointer(void __user *fp, int fplen)
  77 {
  78         if ((((unsigned long) fp) & 15) ||
  79             ((unsigned long)fp) > 0x100000000ULL - fplen)
  80                 return true;
  81         return false;
  82 }
  83
  84 void do_sigreturn32(struct pt_regs *regs)
  85 {
  86         struct signal_frame32 __user *sf;
  87         compat_uptr_t fpu_save;
  88         compat_uptr_t rwin_save;
  89         unsigned int psr, ufp;
  90         unsigned int pc, npc;
  91         sigset_t set;
  92         compat_sigset_t seta;
  93         int err, i;
  94
  95         /* Always make any pending restarted system calls return -EINTR */
  96         current->restart_block.fn = do_no_restart_syscall;
  97
  98         synchronize_user_stack();
  99
 100         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 101         sf = (struct signal_frame32 __user *) regs->u_regs[UREG_FP];
 102
 103         /* 1. Make sure we are not getting garbage from the user */
 104         if (invalid_frame_pointer(sf, sizeof(*sf)))
 105                 goto segv;
 106
 107         if (get_user(ufp, &sf->info.si_regs.u_regs[UREG_FP]))
 108                 goto segv;
 109
 110         if (ufp & 0x7)
 111                 goto segv;
 112
 113         if (__get_user(pc, &sf->info.si_regs.pc) ||
 114             __get_user(npc, &sf->info.si_regs.npc))
 115                 goto segv;
 116
 117         if ((pc | npc) & 3)
 118                 goto segv;
 119
 120         if (test_thread_flag(TIF_32BIT)) {
 121                 pc &= 0xffffffff;
 122                 npc &= 0xffffffff;
 123         }
 124         regs->tpc = pc;
 125         regs->tnpc = npc;
 126
 127         /* 2. Restore the state */
 128         err = __get_user(regs->y, &sf->info.si_regs.y);
 129         err |= __get_user(psr, &sf->info.si_regs.psr);
 130
 131         for (i = UREG_G1; i <= UREG_I7; i++)
 132                 err |= __get_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
 133         if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
 134                 err |= __get_user(i, &sf->v8plus.g_upper[0]);
 135                 if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
 136                         unsigned long asi;
 137
 138                         for (i = UREG_G1; i <= UREG_I7; i++)
 139                                 err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
 140                         err |= __get_user(asi, &sf->v8plus.asi);
 141                         regs->tstate &= ~TSTATE_ASI;
 142                         regs->tstate |= ((asi & 0xffUL) << 24UL);
 143                 }
 144         }
 145
 146         /* User can only change condition codes in %tstate. */
 147         regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
 148         regs->tstate |= psr_to_tstate_icc(psr);
 149
 150         /* Prevent syscall restart.  */
 151         pt_regs_clear_syscall(regs);
 152
 153         err |= __get_user(fpu_save, &sf->fpu_save);
 154         if (!err && fpu_save)
 155                 err |= restore_fpu_state(regs, compat_ptr(fpu_save));
 156         err |= __get_user(rwin_save, &sf->rwin_save);
 157         if (!err && rwin_save) {
 158                 if (restore_rwin_state(compat_ptr(rwin_save)))
 159                         goto segv;
 160         }
 161         err |= __get_user(seta.sig[0], &sf->info.si_mask);
 162         err |= copy_from_user(&seta.sig[1], &sf->extramask,
 163                               (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
 164         if (err)
 165                 goto segv;
 166
 167         set.sig[0] = seta.sig[0] + (((long)seta.sig[1]) << 32);
 168         set_current_blocked(&set);
 169         return;
 170
 171 segv:
 172         force_sig(SIGSEGV);
 173 }
 174
 175 asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
 176 {
 177         struct rt_signal_frame32 __user *sf;
 178         unsigned int psr, pc, npc, ufp;
 179         compat_uptr_t fpu_save;
 180         compat_uptr_t rwin_save;
 181         sigset_t set;
 182         int err, i;
 183
 184         /* Always make any pending restarted system calls return -EINTR */
 185         current->restart_block.fn = do_no_restart_syscall;
 186
 187         synchronize_user_stack();
 188         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 189         sf = (struct rt_signal_frame32 __user *) regs->u_regs[UREG_FP];
 190
 191         /* 1. Make sure we are not getting garbage from the user */
 192         if (invalid_frame_pointer(sf, sizeof(*sf)))
 193                 goto segv;
 194
 195         if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
 196                 goto segv;
 197
 198         if (ufp & 0x7)
 199                 goto segv;
 200
 201         if (__get_user(pc, &sf->regs.pc) ||
 202             __get_user(npc, &sf->regs.npc))
 203                 goto segv;
 204
 205         if ((pc | npc) & 3)
 206                 goto segv;
 207
 208         if (test_thread_flag(TIF_32BIT)) {
 209                 pc &= 0xffffffff;
 210                 npc &= 0xffffffff;
 211         }
 212         regs->tpc = pc;
 213         regs->tnpc = npc;
 214
 215         /* 2. Restore the state */
 216         err = __get_user(regs->y, &sf->regs.y);
 217         err |= __get_user(psr, &sf->regs.psr);
 218
 219         for (i = UREG_G1; i <= UREG_I7; i++)
 220                 err |= __get_user(regs->u_regs[i], &sf->regs.u_regs[i]);
 221         if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
 222                 err |= __get_user(i, &sf->v8plus.g_upper[0]);
 223                 if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
 224                         unsigned long asi;
 225
 226                         for (i = UREG_G1; i <= UREG_I7; i++)
 227                                 err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
 228                         err |= __get_user(asi, &sf->v8plus.asi);
 229                         regs->tstate &= ~TSTATE_ASI;
 230                         regs->tstate |= ((asi & 0xffUL) << 24UL);
 231                 }
 232         }
 233
 234         /* User can only change condition codes in %tstate. */
 235         regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
 236         regs->tstate |= psr_to_tstate_icc(psr);
 237
 238         /* Prevent syscall restart.  */
 239         pt_regs_clear_syscall(regs);
 240
 241         err |= __get_user(fpu_save, &sf->fpu_save);
 242         if (!err && fpu_save)
 243                 err |= restore_fpu_state(regs, compat_ptr(fpu_save));
 244         err |= get_compat_sigset(&set, &sf->mask);
 245         err |= compat_restore_altstack(&sf->stack);
 246         if (err)
 247                 goto segv;
 248
 249         err |= __get_user(rwin_save, &sf->rwin_save);
 250         if (!err && rwin_save) {
 251                 if (restore_rwin_state(compat_ptr(rwin_save)))
 252                         goto segv;
 253         }
 254
 255         set_current_blocked(&set);
 256         return;
 257 segv:
 258         force_sig(SIGSEGV);
 259 }
 260
 261 static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
 262 {
 263         unsigned long sp;
 264
 265         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 266         sp = regs->u_regs[UREG_FP];
 267
 268         /*
 269          * If we are on the alternate signal stack and would overflow it, don't.
 270          * Return an always-bogus address instead so we will die with SIGSEGV.
 271          */
 272         if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
 273                 return (void __user *) -1L;
 274
 275         /* This is the X/Open sanctioned signal stack switching.  */
 276         sp = sigsp(sp, ksig) - framesize;
 277
 278         /* Always align the stack frame.  This handles two cases.  First,
 279          * sigaltstack need not be mindful of platform specific stack
 280          * alignment.  Second, if we took this signal because the stack
 281          * is not aligned properly, we'd like to take the signal cleanly
 282          * and report that.
 283          */
 284         sp &= ~15UL;
 285
 286         return (void __user *) sp;
 287 }
 288
 289 /* The I-cache flush instruction only works in the primary ASI, which
 290  * right now is the nucleus, aka. kernel space.
 291  *
 292  * Therefore we have to kick the instructions out using the kernel
 293  * side linear mapping of the physical address backing the user
 294  * instructions.
 295  */
 296 static void flush_signal_insns(unsigned long address)
 297 {
 298         unsigned long pstate, paddr;
 299         pte_t *ptep, pte;
 300         pgd_t *pgdp;
 301         p4d_t *p4dp;
 302         pud_t *pudp;
 303         pmd_t *pmdp;
 304
 305         /* Commit all stores of the instructions we are about to flush.  */
 306         wmb();
 307
 308         /* Disable cross-call reception.  In this way even a very wide
 309          * munmap() on another cpu can't tear down the page table
 310          * hierarchy from underneath us, since that can't complete
 311          * until the IPI tlb flush returns.
 312          */
 313
 314         __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
 315         __asm__ __volatile__("wrpr %0, %1, %%pstate"
 316                                 : : "r" (pstate), "i" (PSTATE_IE));
 317
 318         pgdp = pgd_offset(current->mm, address);
 319         if (pgd_none(*pgdp))
 320                 goto out_irqs_on;
 321         p4dp = p4d_offset(pgdp, address);
 322         if (p4d_none(*p4dp))
 323                 goto out_irqs_on;
 324         pudp = pud_offset(p4dp, address);
 325         if (pud_none(*pudp))
 326                 goto out_irqs_on;
 327         pmdp = pmd_offset(pudp, address);
 328         if (pmd_none(*pmdp))
 329                 goto out_irqs_on;
 330
 331         ptep = pte_offset_map(pmdp, address);
 332         pte = *ptep;
 333         if (!pte_present(pte))
 334                 goto out_unmap;
 335
 336         paddr = (unsigned long) page_address(pte_page(pte));
 337
 338         __asm__ __volatile__("flush     %0 + %1"
 339                              : /* no outputs */
 340                              : "r" (paddr),
 341                                "r" (address & (PAGE_SIZE - 1))
 342                              : "memory");
 343
 344 out_unmap:
 345         pte_unmap(ptep);
 346 out_irqs_on:
 347         __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
 348
 349 }
 350
 351 static int setup_frame32(struct ksignal *ksig, struct pt_regs *regs,
 352                          sigset_t *oldset)
 353 {
 354         struct signal_frame32 __user *sf;
 355         int i, err, wsaved;
 356         void __user *tail;
 357         int sigframe_size;
 358         u32 psr;
 359         compat_sigset_t seta;
 360
 361         /* 1. Make sure everything is clean */
 362         synchronize_user_stack();
 363         save_and_clear_fpu();
 364
 365         wsaved = get_thread_wsaved();
 366
 367         sigframe_size = sizeof(*sf);
 368         if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 369                 sigframe_size += sizeof(__siginfo_fpu_t);
 370         if (wsaved)
 371                 sigframe_size += sizeof(__siginfo_rwin_t);
 372
 373         sf = (struct signal_frame32 __user *)
 374                 get_sigframe(ksig, regs, sigframe_size);
 375
 376         if (invalid_frame_pointer(sf, sigframe_size)) {
 377                 if (show_unhandled_signals)
 378                         pr_info("%s[%d] bad frame in setup_frame32: %08lx TPC %08lx O7 %08lx\n",
 379                                 current->comm, current->pid, (unsigned long)sf,
 380                                 regs->tpc, regs->u_regs[UREG_I7]);
 381                 force_sigsegv(ksig->sig);
 382                 return -EINVAL;
 383         }
 384
 385         tail = (sf + 1);
 386
 387         /* 2. Save the current process state */
 388         if (test_thread_flag(TIF_32BIT)) {
 389                 regs->tpc &= 0xffffffff;
 390                 regs->tnpc &= 0xffffffff;
 391         }
 392         err  = put_user(regs->tpc, &sf->info.si_regs.pc);
 393         err |= __put_user(regs->tnpc, &sf->info.si_regs.npc);
 394         err |= __put_user(regs->y, &sf->info.si_regs.y);
 395         psr = tstate_to_psr(regs->tstate);
 396         if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 397                 psr |= PSR_EF;
 398         err |= __put_user(psr, &sf->info.si_regs.psr);
 399         for (i = 0; i < 16; i++)
 400                 err |= __put_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
 401         err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
 402         err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
 403         for (i = 1; i < 16; i++)
 404                 err |= __put_user(((u32 *)regs->u_regs)[2*i],
 405                                   &sf->v8plus.g_upper[i]);
 406         err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
 407                           &sf->v8plus.asi);
 408
 409         if (psr & PSR_EF) {
 410                 __siginfo_fpu_t __user *fp = tail;
 411                 tail += sizeof(*fp);
 412                 err |= save_fpu_state(regs, fp);
 413                 err |= __put_user((u64)fp, &sf->fpu_save);
 414         } else {
 415                 err |= __put_user(0, &sf->fpu_save);
 416         }
 417         if (wsaved) {
 418                 __siginfo_rwin_t __user *rwp = tail;
 419                 tail += sizeof(*rwp);
 420                 err |= save_rwin_state(wsaved, rwp);
 421                 err |= __put_user((u64)rwp, &sf->rwin_save);
 422                 set_thread_wsaved(0);
 423         } else {
 424                 err |= __put_user(0, &sf->rwin_save);
 425         }
 426
 427         /* If these change we need to know - assignments to seta relies on these sizes */
 428         BUILD_BUG_ON(_NSIG_WORDS != 1);
 429         BUILD_BUG_ON(_COMPAT_NSIG_WORDS != 2);
 430         seta.sig[1] = (oldset->sig[0] >> 32);
 431         seta.sig[0] = oldset->sig[0];
 432
 433         err |= __put_user(seta.sig[0], &sf->info.si_mask);
 434         err |= __copy_to_user(sf->extramask, &seta.sig[1],
 435                               (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
 436
 437         if (!wsaved) {
 438                 err |= copy_in_user((u32 __user *)sf,
 439                                     (u32 __user *)(regs->u_regs[UREG_FP]),
 440                                     sizeof(struct reg_window32));
 441         } else {
 442                 struct reg_window *rp;
 443
 444                 rp = &current_thread_info()->reg_window[wsaved - 1];
 445                 for (i = 0; i < 8; i++)
 446                         err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
 447                 for (i = 0; i < 6; i++)
 448                         err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
 449                 err |= __put_user(rp->ins[6], &sf->ss.fp);
 450                 err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
 451         }
 452         if (err)
 453                 return err;
 454
 455         /* 3. signal handler back-trampoline and parameters */
 456         regs->u_regs[UREG_FP] = (unsigned long) sf;
 457         regs->u_regs[UREG_I0] = ksig->sig;
 458         regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
 459         regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
 460
 461         /* 4. signal handler */
 462         regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
 463         regs->tnpc = (regs->tpc + 4);
 464         if (test_thread_flag(TIF_32BIT)) {
 465                 regs->tpc &= 0xffffffff;
 466                 regs->tnpc &= 0xffffffff;
 467         }
 468
 469         /* 5. return to kernel instructions */
 470         if (ksig->ka.ka_restorer) {
 471                 regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
 472         } else {
 473                 unsigned long address = ((unsigned long)&(sf->insns[0]));
 474
 475                 regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
 476
 477                 err  = __put_user(0x821020d8, &sf->insns[0]); /*mov __NR_sigreturn, %g1*/
 478                 err |= __put_user(0x91d02010, &sf->insns[1]); /*t 0x10*/
 479                 if (err)
 480                         return err;
 481                 flush_signal_insns(address);
 482         }
 483         return 0;
 484 }
 485
 486 static int setup_rt_frame32(struct ksignal *ksig, struct pt_regs *regs,
 487                             sigset_t *oldset)
 488 {
 489         struct rt_signal_frame32 __user *sf;
 490         int i, err, wsaved;
 491         void __user *tail;
 492         int sigframe_size;
 493         u32 psr;
 494
 495         /* 1. Make sure everything is clean */
 496         synchronize_user_stack();
 497         save_and_clear_fpu();
 498
 499         wsaved = get_thread_wsaved();
 500
 501         sigframe_size = sizeof(*sf);
 502         if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 503                 sigframe_size += sizeof(__siginfo_fpu_t);
 504         if (wsaved)
 505                 sigframe_size += sizeof(__siginfo_rwin_t);
 506
 507         sf = (struct rt_signal_frame32 __user *)
 508                 get_sigframe(ksig, regs, sigframe_size);
 509
 510         if (invalid_frame_pointer(sf, sigframe_size)) {
 511                 if (show_unhandled_signals)
 512                         pr_info("%s[%d] bad frame in setup_rt_frame32: %08lx TPC %08lx O7 %08lx\n",
 513                                 current->comm, current->pid, (unsigned long)sf,
 514                                 regs->tpc, regs->u_regs[UREG_I7]);
 515                 force_sigsegv(ksig->sig);
 516                 return -EINVAL;
 517         }
 518
 519         tail = (sf + 1);
 520
 521         /* 2. Save the current process state */
 522         if (test_thread_flag(TIF_32BIT)) {
 523                 regs->tpc &= 0xffffffff;
 524                 regs->tnpc &= 0xffffffff;
 525         }
 526         err  = put_user(regs->tpc, &sf->regs.pc);
 527         err |= __put_user(regs->tnpc, &sf->regs.npc);
 528         err |= __put_user(regs->y, &sf->regs.y);
 529         psr = tstate_to_psr(regs->tstate);
 530         if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 531                 psr |= PSR_EF;
 532         err |= __put_user(psr, &sf->regs.psr);
 533         for (i = 0; i < 16; i++)
 534                 err |= __put_user(regs->u_regs[i], &sf->regs.u_regs[i]);
 535         err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
 536         err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
 537         for (i = 1; i < 16; i++)
 538                 err |= __put_user(((u32 *)regs->u_regs)[2*i],
 539                                   &sf->v8plus.g_upper[i]);
 540         err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
 541                           &sf->v8plus.asi);
 542
 543         if (psr & PSR_EF) {
 544                 __siginfo_fpu_t __user *fp = tail;
 545                 tail += sizeof(*fp);
 546                 err |= save_fpu_state(regs, fp);
 547                 err |= __put_user((u64)fp, &sf->fpu_save);
 548         } else {
 549                 err |= __put_user(0, &sf->fpu_save);
 550         }
 551         if (wsaved) {
 552                 __siginfo_rwin_t __user *rwp = tail;
 553                 tail += sizeof(*rwp);
 554                 err |= save_rwin_state(wsaved, rwp);
 555                 err |= __put_user((u64)rwp, &sf->rwin_save);
 556                 set_thread_wsaved(0);
 557         } else {
 558                 err |= __put_user(0, &sf->rwin_save);
 559         }
 560
 561         /* Update the siginfo structure.  */
 562         err |= copy_siginfo_to_user32(&sf->info, &ksig->info);
 563
 564         /* Setup sigaltstack */
 565         err |= __compat_save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
 566
 567         err |= put_compat_sigset(&sf->mask, oldset, sizeof(compat_sigset_t));
 568
 569         if (!wsaved) {
 570                 err |= copy_in_user((u32 __user *)sf,
 571                                     (u32 __user *)(regs->u_regs[UREG_FP]),
 572                                     sizeof(struct reg_window32));
 573         } else {
 574                 struct reg_window *rp;
 575
 576                 rp = &current_thread_info()->reg_window[wsaved - 1];
 577                 for (i = 0; i < 8; i++)
 578                         err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
 579                 for (i = 0; i < 6; i++)
 580                         err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
 581                 err |= __put_user(rp->ins[6], &sf->ss.fp);
 582                 err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
 583         }
 584         if (err)
 585                 return err;
 586
 587         /* 3. signal handler back-trampoline and parameters */
 588         regs->u_regs[UREG_FP] = (unsigned long) sf;
 589         regs->u_regs[UREG_I0] = ksig->sig;
 590         regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
 591         regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
 592
 593         /* 4. signal handler */
 594         regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
 595         regs->tnpc = (regs->tpc + 4);
 596         if (test_thread_flag(TIF_32BIT)) {
 597                 regs->tpc &= 0xffffffff;
 598                 regs->tnpc &= 0xffffffff;
 599         }
 600
 601         /* 5. return to kernel instructions */
 602         if (ksig->ka.ka_restorer)
 603                 regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
 604         else {
 605                 unsigned long address = ((unsigned long)&(sf->insns[0]));
 606
 607                 regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
 608
 609                 /* mov __NR_rt_sigreturn, %g1 */
 610                 err |= __put_user(0x82102065, &sf->insns[0]);
 611
 612                 /* t 0x10 */
 613                 err |= __put_user(0x91d02010, &sf->insns[1]);
 614                 if (err)
 615                         return err;
 616
 617                 flush_signal_insns(address);
 618         }
 619         return 0;
 620 }
 621
 622 static inline void handle_signal32(struct ksignal *ksig,
 623                                   struct pt_regs *regs)
 624 {
 625         sigset_t *oldset = sigmask_to_save();
 626         int err;
 627
 628         if (ksig->ka.sa.sa_flags & SA_SIGINFO)
 629                 err = setup_rt_frame32(ksig, regs, oldset);
 630         else
 631                 err = setup_frame32(ksig, regs, oldset);
 632
 633         signal_setup_done(err, ksig, 0);
 634 }
 635
 636 static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
 637                                      struct sigaction *sa)
 638 {
 639         switch (regs->u_regs[UREG_I0]) {
 640         case ERESTART_RESTARTBLOCK:
 641         case ERESTARTNOHAND:
 642         no_system_call_restart:
 643                 regs->u_regs[UREG_I0] = EINTR;
 644                 regs->tstate |= TSTATE_ICARRY;
 645                 break;
 646         case ERESTARTSYS:
 647                 if (!(sa->sa_flags & SA_RESTART))
 648                         goto no_system_call_restart;
 649                 fallthrough;
 650         case ERESTARTNOINTR:
 651                 regs->u_regs[UREG_I0] = orig_i0;
 652                 regs->tpc -= 4;
 653                 regs->tnpc -= 4;
 654         }
 655 }
 656
 657 /* Note that 'init' is a special process: it doesn't get signals it doesn't
 658  * want to handle. Thus you cannot kill init even with a SIGKILL even by
 659  * mistake.
 660  */
 661 void do_signal32(struct pt_regs * regs)
 662 {
 663         struct ksignal ksig;
 664         unsigned long orig_i0 = 0;
 665         int restart_syscall = 0;
 666         bool has_handler = get_signal(&ksig);
 667
 668         if (pt_regs_is_syscall(regs) &&
 669             (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
 670                 restart_syscall = 1;
 671                 orig_i0 = regs->u_regs[UREG_G6];
 672         }
 673
 674         if (has_handler) {
 675                 if (restart_syscall)
 676                         syscall_restart32(orig_i0, regs, &ksig.ka.sa);
 677                 handle_signal32(&ksig, regs);
 678         } else {
 679                 if (restart_syscall) {
 680                         switch (regs->u_regs[UREG_I0]) {
 681                         case ERESTARTNOHAND:
 682                         case ERESTARTSYS:
 683                         case ERESTARTNOINTR:
 684                                 /* replay the system call when we are done */
 685                                 regs->u_regs[UREG_I0] = orig_i0;
 686                                 regs->tpc -= 4;
 687                                 regs->tnpc -= 4;
 688                                 pt_regs_clear_syscall(regs);
 689                                 fallthrough;
 690                         case ERESTART_RESTARTBLOCK:
 691                                 regs->u_regs[UREG_G1] = __NR_restart_syscall;
 692                                 regs->tpc -= 4;
 693                                 regs->tnpc -= 4;
 694                                 pt_regs_clear_syscall(regs);
 695                         }
 696                 }
 697                 restore_saved_sigmask();
 698         }
 699 }
 700
 701 struct sigstack32 {
 702         u32 the_stack;
 703         int cur_status;
 704 };
 705
 706 asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp)
 707 {
 708         struct sigstack32 __user *ssptr =
 709                 (struct sigstack32 __user *)((unsigned long)(u_ssptr));
 710         struct sigstack32 __user *ossptr =
 711                 (struct sigstack32 __user *)((unsigned long)(u_ossptr));
 712         int ret = -EFAULT;
 713
 714         /* First see if old state is wanted. */
 715         if (ossptr) {
 716                 if (put_user(current->sas_ss_sp + current->sas_ss_size,
 717                              &ossptr->the_stack) ||
 718                     __put_user(on_sig_stack(sp), &ossptr->cur_status))
 719                         goto out;
 720         }
 721
 722         /* Now see if we want to update the new state. */
 723         if (ssptr) {
 724                 u32 ss_sp;
 725
 726                 if (get_user(ss_sp, &ssptr->the_stack))
 727                         goto out;
 728
 729                 /* If the current stack was set with sigaltstack, don't
 730                  * swap stacks while we are on it.
 731                  */
 732                 ret = -EPERM;
 733                 if (current->sas_ss_sp && on_sig_stack(sp))
 734                         goto out;
 735
 736                 /* Since we don't know the extent of the stack, and we don't
 737                  * track onstack-ness, but rather calculate it, we must
 738                  * presume a size.  Ho hum this interface is lossy.
 739                  */
 740                 current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
 741                 current->sas_ss_size = SIGSTKSZ;
 742         }
 743
 744         ret = 0;
 745 out:
 746         return ret;
 747 }
 748
 749 /*
 750  * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
 751  * changes likely come with new fields that should be added below.
 752  */
 753 static_assert(NSIGILL   == 11);
 754 static_assert(NSIGFPE   == 15);
 755 static_assert(NSIGSEGV  == 9);
 756 static_assert(NSIGBUS   == 5);
 757 static_assert(NSIGTRAP  == 6);
 758 static_assert(NSIGCHLD  == 6);
 759 static_assert(NSIGSYS   == 2);
 760 static_assert(sizeof(compat_siginfo_t) == 128);
 761 static_assert(__alignof__(compat_siginfo_t) == 4);
 762 static_assert(offsetof(compat_siginfo_t, si_signo)      == 0x00);
 763 static_assert(offsetof(compat_siginfo_t, si_errno)      == 0x04);
 764 static_assert(offsetof(compat_siginfo_t, si_code)       == 0x08);
 765 static_assert(offsetof(compat_siginfo_t, si_pid)        == 0x0c);
 766 static_assert(offsetof(compat_siginfo_t, si_uid)        == 0x10);
 767 static_assert(offsetof(compat_siginfo_t, si_tid)        == 0x0c);
 768 static_assert(offsetof(compat_siginfo_t, si_overrun)    == 0x10);
 769 static_assert(offsetof(compat_siginfo_t, si_status)     == 0x14);
 770 static_assert(offsetof(compat_siginfo_t, si_utime)      == 0x18);
 771 static_assert(offsetof(compat_siginfo_t, si_stime)      == 0x1c);
 772 static_assert(offsetof(compat_siginfo_t, si_value)      == 0x14);
 773 static_assert(offsetof(compat_siginfo_t, si_int)        == 0x14);
 774 static_assert(offsetof(compat_siginfo_t, si_ptr)        == 0x14);
 775 static_assert(offsetof(compat_siginfo_t, si_addr)       == 0x0c);
 776 static_assert(offsetof(compat_siginfo_t, si_trapno)     == 0x10);
 777 static_assert(offsetof(compat_siginfo_t, si_addr_lsb)   == 0x10);
 778 static_assert(offsetof(compat_siginfo_t, si_lower)      == 0x14);
 779 static_assert(offsetof(compat_siginfo_t, si_upper)      == 0x18);
 780 static_assert(offsetof(compat_siginfo_t, si_pkey)       == 0x14);
 781 static_assert(offsetof(compat_siginfo_t, si_perf_data)  == 0x10);
 782 static_assert(offsetof(compat_siginfo_t, si_perf_type)  == 0x14);
 783 static_assert(offsetof(compat_siginfo_t, si_band)       == 0x0c);
 784 static_assert(offsetof(compat_siginfo_t, si_fd)         == 0x10);