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v5.9
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
   4 *
   5 *  PowerPC version
   6 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   7 * Copyright (C) 2001 IBM
   8 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   9 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
  10 *
  11 *  Derived from "arch/i386/kernel/signal.c"
  12 *    Copyright (C) 1991, 1992 Linus Torvalds
  13 *    1997-11-28  Modified for POSIX.1b signals by Richard Henderson
 
 
 
 
 
  14 */
  15
  16#include <linux/sched.h>
  17#include <linux/mm.h>
  18#include <linux/smp.h>
  19#include <linux/kernel.h>
  20#include <linux/signal.h>
  21#include <linux/errno.h>
  22#include <linux/elf.h>
  23#include <linux/ptrace.h>
  24#include <linux/pagemap.h>
  25#include <linux/ratelimit.h>
  26#include <linux/syscalls.h>
  27#ifdef CONFIG_PPC64
 
  28#include <linux/compat.h>
  29#else
  30#include <linux/wait.h>
  31#include <linux/unistd.h>
  32#include <linux/stddef.h>
  33#include <linux/tty.h>
  34#include <linux/binfmts.h>
 
  35#endif
  36
  37#include <linux/uaccess.h>
  38#include <asm/cacheflush.h>
  39#include <asm/syscalls.h>
  40#include <asm/sigcontext.h>
  41#include <asm/vdso.h>
  42#include <asm/switch_to.h>
  43#include <asm/tm.h>
  44#include <asm/asm-prototypes.h>
  45#ifdef CONFIG_PPC64
  46#include "ppc32.h"
  47#include <asm/unistd.h>
  48#else
  49#include <asm/ucontext.h>
 
  50#endif
  51
  52#include "signal.h"
  53
 
  54
  55#ifdef CONFIG_PPC64
 
 
 
 
 
 
 
  56#define old_sigaction	old_sigaction32
  57#define sigcontext	sigcontext32
  58#define mcontext	mcontext32
  59#define ucontext	ucontext32
  60
  61#define __save_altstack __compat_save_altstack
  62
  63/*
  64 * Userspace code may pass a ucontext which doesn't include VSX added
  65 * at the end.  We need to check for this case.
  66 */
  67#define UCONTEXTSIZEWITHOUTVSX \
  68		(sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
  69
  70/*
  71 * Returning 0 means we return to userspace via
  72 * ret_from_except and thus restore all user
  73 * registers from *regs.  This is what we need
  74 * to do when a signal has been delivered.
  75 */
  76
  77#define GP_REGS_SIZE	min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
  78#undef __SIGNAL_FRAMESIZE
  79#define __SIGNAL_FRAMESIZE	__SIGNAL_FRAMESIZE32
  80#undef ELF_NVRREG
  81#define ELF_NVRREG	ELF_NVRREG32
  82
  83/*
  84 * Functions for flipping sigsets (thanks to brain dead generic
  85 * implementation that makes things simple for little endian only)
  86 */
  87static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
  88{
  89	return put_compat_sigset(uset, set, sizeof(*uset));
 
 
 
 
 
 
 
 
 
 
 
 
  90}
  91
  92static inline int get_sigset_t(sigset_t *set,
  93			       const compat_sigset_t __user *uset)
  94{
  95	return get_compat_sigset(set, uset);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  96}
  97
  98#define to_user_ptr(p)		ptr_to_compat(p)
  99#define from_user_ptr(p)	compat_ptr(p)
 100
 101static inline int save_general_regs(struct pt_regs *regs,
 102		struct mcontext __user *frame)
 103{
 104	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
 105	int val, i;
 106
 107	WARN_ON(!FULL_REGS(regs));
 108
 109	for (i = 0; i <= PT_RESULT; i ++) {
 110		/* Force usr to alway see softe as 1 (interrupts enabled) */
 111		if (i == PT_SOFTE)
 112			val = 1;
 113		else
 114			val = gregs[i];
 115
 116		if (__put_user(val, &frame->mc_gregs[i]))
 117			return -EFAULT;
 118	}
 119	return 0;
 120}
 121
 122static inline int restore_general_regs(struct pt_regs *regs,
 123		struct mcontext __user *sr)
 124{
 125	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
 126	int i;
 127
 128	for (i = 0; i <= PT_RESULT; i++) {
 129		if ((i == PT_MSR) || (i == PT_SOFTE))
 130			continue;
 131		if (__get_user(gregs[i], &sr->mc_gregs[i]))
 132			return -EFAULT;
 133	}
 134	return 0;
 135}
 136
 137#else /* CONFIG_PPC64 */
 138
 139#define GP_REGS_SIZE	min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
 140
 141static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
 142{
 143	return copy_to_user(uset, set, sizeof(*uset));
 144}
 145
 146static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
 147{
 148	return copy_from_user(set, uset, sizeof(*uset));
 149}
 150
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 151#define to_user_ptr(p)		((unsigned long)(p))
 152#define from_user_ptr(p)	((void __user *)(p))
 153
 154static inline int save_general_regs(struct pt_regs *regs,
 155		struct mcontext __user *frame)
 156{
 157	WARN_ON(!FULL_REGS(regs));
 158	return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
 159}
 160
 161static inline int restore_general_regs(struct pt_regs *regs,
 162		struct mcontext __user *sr)
 163{
 164	/* copy up to but not including MSR */
 165	if (__copy_from_user(regs, &sr->mc_gregs,
 166				PT_MSR * sizeof(elf_greg_t)))
 167		return -EFAULT;
 168	/* copy from orig_r3 (the word after the MSR) up to the end */
 169	if (__copy_from_user(&regs->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
 170				GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
 171		return -EFAULT;
 172	return 0;
 173}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 174#endif
 175
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 176/*
 177 * When we have signals to deliver, we set up on the
 178 * user stack, going down from the original stack pointer:
 179 *	an ABI gap of 56 words
 180 *	an mcontext struct
 181 *	a sigcontext struct
 182 *	a gap of __SIGNAL_FRAMESIZE bytes
 183 *
 184 * Each of these things must be a multiple of 16 bytes in size. The following
 185 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
 186 *
 187 */
 188struct sigframe {
 189	struct sigcontext sctx;		/* the sigcontext */
 190	struct mcontext	mctx;		/* all the register values */
 191#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 192	struct sigcontext sctx_transact;
 193	struct mcontext	mctx_transact;
 194#endif
 195	/*
 196	 * Programs using the rs6000/xcoff abi can save up to 19 gp
 197	 * regs and 18 fp regs below sp before decrementing it.
 198	 */
 199	int			abigap[56];
 200};
 201
 202/* We use the mc_pad field for the signal return trampoline. */
 203#define tramp	mc_pad
 204
 205/*
 206 *  When we have rt signals to deliver, we set up on the
 207 *  user stack, going down from the original stack pointer:
 208 *	one rt_sigframe struct (siginfo + ucontext + ABI gap)
 209 *	a gap of __SIGNAL_FRAMESIZE+16 bytes
 210 *  (the +16 is to get the siginfo and ucontext in the same
 211 *  positions as in older kernels).
 212 *
 213 *  Each of these things must be a multiple of 16 bytes in size.
 214 *
 215 */
 216struct rt_sigframe {
 217#ifdef CONFIG_PPC64
 218	compat_siginfo_t info;
 219#else
 220	struct siginfo info;
 221#endif
 222	struct ucontext	uc;
 223#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 224	struct ucontext	uc_transact;
 225#endif
 226	/*
 227	 * Programs using the rs6000/xcoff abi can save up to 19 gp
 228	 * regs and 18 fp regs below sp before decrementing it.
 229	 */
 230	int			abigap[56];
 231};
 232
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 233/*
 234 * Save the current user registers on the user stack.
 235 * We only save the altivec/spe registers if the process has used
 236 * altivec/spe instructions at some point.
 237 */
 238static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
 239			  struct mcontext __user *tm_frame, int sigret,
 240			  int ctx_has_vsx_region)
 241{
 242	unsigned long msr = regs->msr;
 243
 244	/* Make sure floating point registers are stored in regs */
 245	flush_fp_to_thread(current);
 246
 247	/* save general registers */
 248	if (save_general_regs(regs, frame))
 249		return 1;
 250
 251#ifdef CONFIG_ALTIVEC
 252	/* save altivec registers */
 253	if (current->thread.used_vr) {
 254		flush_altivec_to_thread(current);
 255		if (__copy_to_user(&frame->mc_vregs, &current->thread.vr_state,
 256				   ELF_NVRREG * sizeof(vector128)))
 257			return 1;
 258		/* set MSR_VEC in the saved MSR value to indicate that
 259		   frame->mc_vregs contains valid data */
 260		msr |= MSR_VEC;
 261	}
 262	/* else assert((regs->msr & MSR_VEC) == 0) */
 263
 264	/* We always copy to/from vrsave, it's 0 if we don't have or don't
 265	 * use altivec. Since VSCR only contains 32 bits saved in the least
 266	 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
 267	 * most significant bits of that same vector. --BenH
 268	 * Note that the current VRSAVE value is in the SPR at this point.
 269	 */
 270	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 271		current->thread.vrsave = mfspr(SPRN_VRSAVE);
 272	if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
 273		return 1;
 274#endif /* CONFIG_ALTIVEC */
 275	if (copy_fpr_to_user(&frame->mc_fregs, current))
 276		return 1;
 277
 278	/*
 279	 * Clear the MSR VSX bit to indicate there is no valid state attached
 280	 * to this context, except in the specific case below where we set it.
 281	 */
 282	msr &= ~MSR_VSX;
 283#ifdef CONFIG_VSX
 284	/*
 285	 * Copy VSR 0-31 upper half from thread_struct to local
 286	 * buffer, then write that to userspace.  Also set MSR_VSX in
 287	 * the saved MSR value to indicate that frame->mc_vregs
 288	 * contains valid data
 289	 */
 290	if (current->thread.used_vsr && ctx_has_vsx_region) {
 291		flush_vsx_to_thread(current);
 292		if (copy_vsx_to_user(&frame->mc_vsregs, current))
 293			return 1;
 294		msr |= MSR_VSX;
 295	}
 296#endif /* CONFIG_VSX */
 297#ifdef CONFIG_SPE
 298	/* save spe registers */
 299	if (current->thread.used_spe) {
 300		flush_spe_to_thread(current);
 301		if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
 302				   ELF_NEVRREG * sizeof(u32)))
 303			return 1;
 304		/* set MSR_SPE in the saved MSR value to indicate that
 305		   frame->mc_vregs contains valid data */
 306		msr |= MSR_SPE;
 307	}
 308	/* else assert((regs->msr & MSR_SPE) == 0) */
 309
 310	/* We always copy to/from spefscr */
 311	if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
 312		return 1;
 313#endif /* CONFIG_SPE */
 314
 315	if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
 316		return 1;
 317	/* We need to write 0 the MSR top 32 bits in the tm frame so that we
 318	 * can check it on the restore to see if TM is active
 319	 */
 320	if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
 321		return 1;
 322
 323	if (sigret) {
 324		/* Set up the sigreturn trampoline: li 0,sigret; sc */
 325		if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
 326		    || __put_user(PPC_INST_SC, &frame->tramp[1]))
 327			return 1;
 328		flush_icache_range((unsigned long) &frame->tramp[0],
 329				   (unsigned long) &frame->tramp[2]);
 330	}
 331
 332	return 0;
 333}
 334
 335#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 336/*
 337 * Save the current user registers on the user stack.
 338 * We only save the altivec/spe registers if the process has used
 339 * altivec/spe instructions at some point.
 340 * We also save the transactional registers to a second ucontext in the
 341 * frame.
 342 *
 343 * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
 344 */
 345static int save_tm_user_regs(struct pt_regs *regs,
 346			     struct mcontext __user *frame,
 347			     struct mcontext __user *tm_frame, int sigret,
 348			     unsigned long msr)
 349{
 350	WARN_ON(tm_suspend_disabled);
 351
 352	/* Save both sets of general registers */
 353	if (save_general_regs(&current->thread.ckpt_regs, frame)
 354	    || save_general_regs(regs, tm_frame))
 355		return 1;
 356
 357	/* Stash the top half of the 64bit MSR into the 32bit MSR word
 358	 * of the transactional mcontext.  This way we have a backward-compatible
 359	 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
 360	 * also look at what type of transaction (T or S) was active at the
 361	 * time of the signal.
 362	 */
 363	if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
 364		return 1;
 365
 366#ifdef CONFIG_ALTIVEC
 367	/* save altivec registers */
 368	if (current->thread.used_vr) {
 369		if (__copy_to_user(&frame->mc_vregs, &current->thread.ckvr_state,
 370				   ELF_NVRREG * sizeof(vector128)))
 371			return 1;
 372		if (msr & MSR_VEC) {
 373			if (__copy_to_user(&tm_frame->mc_vregs,
 374					   &current->thread.vr_state,
 375					   ELF_NVRREG * sizeof(vector128)))
 376				return 1;
 377		} else {
 378			if (__copy_to_user(&tm_frame->mc_vregs,
 379					   &current->thread.ckvr_state,
 380					   ELF_NVRREG * sizeof(vector128)))
 381				return 1;
 382		}
 383
 384		/* set MSR_VEC in the saved MSR value to indicate that
 385		 * frame->mc_vregs contains valid data
 386		 */
 387		msr |= MSR_VEC;
 388	}
 389
 390	/* We always copy to/from vrsave, it's 0 if we don't have or don't
 391	 * use altivec. Since VSCR only contains 32 bits saved in the least
 392	 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
 393	 * most significant bits of that same vector. --BenH
 394	 */
 395	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 396		current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
 397	if (__put_user(current->thread.ckvrsave,
 398		       (u32 __user *)&frame->mc_vregs[32]))
 399		return 1;
 400	if (msr & MSR_VEC) {
 401		if (__put_user(current->thread.vrsave,
 402			       (u32 __user *)&tm_frame->mc_vregs[32]))
 403			return 1;
 404	} else {
 405		if (__put_user(current->thread.ckvrsave,
 406			       (u32 __user *)&tm_frame->mc_vregs[32]))
 407			return 1;
 408	}
 409#endif /* CONFIG_ALTIVEC */
 410
 411	if (copy_ckfpr_to_user(&frame->mc_fregs, current))
 412		return 1;
 413	if (msr & MSR_FP) {
 414		if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
 415			return 1;
 416	} else {
 417		if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
 418			return 1;
 419	}
 420
 421#ifdef CONFIG_VSX
 422	/*
 423	 * Copy VSR 0-31 upper half from thread_struct to local
 424	 * buffer, then write that to userspace.  Also set MSR_VSX in
 425	 * the saved MSR value to indicate that frame->mc_vregs
 426	 * contains valid data
 427	 */
 428	if (current->thread.used_vsr) {
 429		if (copy_ckvsx_to_user(&frame->mc_vsregs, current))
 430			return 1;
 431		if (msr & MSR_VSX) {
 432			if (copy_vsx_to_user(&tm_frame->mc_vsregs,
 433						      current))
 434				return 1;
 435		} else {
 436			if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
 437				return 1;
 438		}
 439
 440		msr |= MSR_VSX;
 441	}
 442#endif /* CONFIG_VSX */
 443#ifdef CONFIG_SPE
 444	/* SPE regs are not checkpointed with TM, so this section is
 445	 * simply the same as in save_user_regs().
 446	 */
 447	if (current->thread.used_spe) {
 448		flush_spe_to_thread(current);
 449		if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
 450				   ELF_NEVRREG * sizeof(u32)))
 451			return 1;
 452		/* set MSR_SPE in the saved MSR value to indicate that
 453		 * frame->mc_vregs contains valid data */
 454		msr |= MSR_SPE;
 455	}
 456
 457	/* We always copy to/from spefscr */
 458	if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
 459		return 1;
 460#endif /* CONFIG_SPE */
 461
 462	if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
 463		return 1;
 464	if (sigret) {
 465		/* Set up the sigreturn trampoline: li 0,sigret; sc */
 466		if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
 467		    || __put_user(PPC_INST_SC, &frame->tramp[1]))
 468			return 1;
 469		flush_icache_range((unsigned long) &frame->tramp[0],
 470				   (unsigned long) &frame->tramp[2]);
 471	}
 472
 473	return 0;
 474}
 475#endif
 476
 477/*
 478 * Restore the current user register values from the user stack,
 479 * (except for MSR).
 480 */
 481static long restore_user_regs(struct pt_regs *regs,
 482			      struct mcontext __user *sr, int sig)
 483{
 484	long err;
 485	unsigned int save_r2 = 0;
 486	unsigned long msr;
 487#ifdef CONFIG_VSX
 488	int i;
 489#endif
 490
 491	/*
 492	 * restore general registers but not including MSR or SOFTE. Also
 493	 * take care of keeping r2 (TLS) intact if not a signal
 494	 */
 495	if (!sig)
 496		save_r2 = (unsigned int)regs->gpr[2];
 497	err = restore_general_regs(regs, sr);
 498	set_trap_norestart(regs);
 499	err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
 500	if (!sig)
 501		regs->gpr[2] = (unsigned long) save_r2;
 502	if (err)
 503		return 1;
 504
 505	/* if doing signal return, restore the previous little-endian mode */
 506	if (sig)
 507		regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
 508
 
 
 
 
 
 
 
 
 
 509#ifdef CONFIG_ALTIVEC
 510	/*
 511	 * Force the process to reload the altivec registers from
 512	 * current->thread when it next does altivec instructions
 513	 */
 514	regs->msr &= ~MSR_VEC;
 515	if (msr & MSR_VEC) {
 516		/* restore altivec registers from the stack */
 517		if (__copy_from_user(&current->thread.vr_state, &sr->mc_vregs,
 518				     sizeof(sr->mc_vregs)))
 519			return 1;
 520		current->thread.used_vr = true;
 521	} else if (current->thread.used_vr)
 522		memset(&current->thread.vr_state, 0,
 523		       ELF_NVRREG * sizeof(vector128));
 524
 525	/* Always get VRSAVE back */
 526	if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
 527		return 1;
 528	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 529		mtspr(SPRN_VRSAVE, current->thread.vrsave);
 530#endif /* CONFIG_ALTIVEC */
 531	if (copy_fpr_from_user(current, &sr->mc_fregs))
 532		return 1;
 533
 534#ifdef CONFIG_VSX
 535	/*
 536	 * Force the process to reload the VSX registers from
 537	 * current->thread when it next does VSX instruction.
 538	 */
 539	regs->msr &= ~MSR_VSX;
 540	if (msr & MSR_VSX) {
 541		/*
 542		 * Restore altivec registers from the stack to a local
 543		 * buffer, then write this out to the thread_struct
 544		 */
 545		if (copy_vsx_from_user(current, &sr->mc_vsregs))
 546			return 1;
 547		current->thread.used_vsr = true;
 548	} else if (current->thread.used_vsr)
 549		for (i = 0; i < 32 ; i++)
 550			current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
 551#endif /* CONFIG_VSX */
 552	/*
 553	 * force the process to reload the FP registers from
 554	 * current->thread when it next does FP instructions
 555	 */
 556	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
 557
 558#ifdef CONFIG_SPE
 559	/* force the process to reload the spe registers from
 560	   current->thread when it next does spe instructions */
 561	regs->msr &= ~MSR_SPE;
 562	if (msr & MSR_SPE) {
 563		/* restore spe registers from the stack */
 564		if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
 565				     ELF_NEVRREG * sizeof(u32)))
 566			return 1;
 567		current->thread.used_spe = true;
 568	} else if (current->thread.used_spe)
 569		memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
 570
 571	/* Always get SPEFSCR back */
 572	if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
 573		return 1;
 574#endif /* CONFIG_SPE */
 575
 576	return 0;
 577}
 578
 579#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 580/*
 581 * Restore the current user register values from the user stack, except for
 582 * MSR, and recheckpoint the original checkpointed register state for processes
 583 * in transactions.
 584 */
 585static long restore_tm_user_regs(struct pt_regs *regs,
 586				 struct mcontext __user *sr,
 587				 struct mcontext __user *tm_sr)
 588{
 589	long err;
 590	unsigned long msr, msr_hi;
 591#ifdef CONFIG_VSX
 592	int i;
 593#endif
 594
 595	if (tm_suspend_disabled)
 596		return 1;
 597	/*
 598	 * restore general registers but not including MSR or SOFTE. Also
 599	 * take care of keeping r2 (TLS) intact if not a signal.
 600	 * See comment in signal_64.c:restore_tm_sigcontexts();
 601	 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
 602	 * were set by the signal delivery.
 603	 */
 604	err = restore_general_regs(regs, tm_sr);
 605	err |= restore_general_regs(&current->thread.ckpt_regs, sr);
 606
 607	err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
 608
 609	err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
 610	if (err)
 611		return 1;
 612
 613	/* Restore the previous little-endian mode */
 614	regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
 615
 616#ifdef CONFIG_ALTIVEC
 617	regs->msr &= ~MSR_VEC;
 618	if (msr & MSR_VEC) {
 619		/* restore altivec registers from the stack */
 620		if (__copy_from_user(&current->thread.ckvr_state, &sr->mc_vregs,
 621				     sizeof(sr->mc_vregs)) ||
 622		    __copy_from_user(&current->thread.vr_state,
 623				     &tm_sr->mc_vregs,
 624				     sizeof(sr->mc_vregs)))
 625			return 1;
 626		current->thread.used_vr = true;
 627	} else if (current->thread.used_vr) {
 628		memset(&current->thread.vr_state, 0,
 629		       ELF_NVRREG * sizeof(vector128));
 630		memset(&current->thread.ckvr_state, 0,
 631		       ELF_NVRREG * sizeof(vector128));
 632	}
 633
 634	/* Always get VRSAVE back */
 635	if (__get_user(current->thread.ckvrsave,
 636		       (u32 __user *)&sr->mc_vregs[32]) ||
 637	    __get_user(current->thread.vrsave,
 638		       (u32 __user *)&tm_sr->mc_vregs[32]))
 639		return 1;
 640	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 641		mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
 642#endif /* CONFIG_ALTIVEC */
 643
 644	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 645
 646	if (copy_fpr_from_user(current, &sr->mc_fregs) ||
 647	    copy_ckfpr_from_user(current, &tm_sr->mc_fregs))
 648		return 1;
 
 649
 650#ifdef CONFIG_VSX
 651	regs->msr &= ~MSR_VSX;
 652	if (msr & MSR_VSX) {
 653		/*
 654		 * Restore altivec registers from the stack to a local
 655		 * buffer, then write this out to the thread_struct
 656		 */
 657		if (copy_vsx_from_user(current, &tm_sr->mc_vsregs) ||
 658		    copy_ckvsx_from_user(current, &sr->mc_vsregs))
 659			return 1;
 660		current->thread.used_vsr = true;
 661	} else if (current->thread.used_vsr)
 662		for (i = 0; i < 32 ; i++) {
 663			current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
 664			current->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
 665		}
 666#endif /* CONFIG_VSX */
 667
 668#ifdef CONFIG_SPE
 669	/* SPE regs are not checkpointed with TM, so this section is
 670	 * simply the same as in restore_user_regs().
 671	 */
 672	regs->msr &= ~MSR_SPE;
 673	if (msr & MSR_SPE) {
 674		if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
 675				     ELF_NEVRREG * sizeof(u32)))
 676			return 1;
 677		current->thread.used_spe = true;
 678	} else if (current->thread.used_spe)
 679		memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
 
 
 
 
 680
 681	/* Always get SPEFSCR back */
 682	if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
 683		       + ELF_NEVRREG))
 684		return 1;
 685#endif /* CONFIG_SPE */
 686
 687	/* Get the top half of the MSR from the user context */
 688	if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
 689		return 1;
 690	msr_hi <<= 32;
 691	/* If TM bits are set to the reserved value, it's an invalid context */
 692	if (MSR_TM_RESV(msr_hi))
 693		return 1;
 694
 695	/*
 696	 * Disabling preemption, since it is unsafe to be preempted
 697	 * with MSR[TS] set without recheckpointing.
 698	 */
 699	preempt_disable();
 700
 701	/*
 702	 * CAUTION:
 703	 * After regs->MSR[TS] being updated, make sure that get_user(),
 704	 * put_user() or similar functions are *not* called. These
 705	 * functions can generate page faults which will cause the process
 706	 * to be de-scheduled with MSR[TS] set but without calling
 707	 * tm_recheckpoint(). This can cause a bug.
 708	 *
 709	 * Pull in the MSR TM bits from the user context
 710	 */
 711	regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK);
 712	/* Now, recheckpoint.  This loads up all of the checkpointed (older)
 713	 * registers, including FP and V[S]Rs.  After recheckpointing, the
 714	 * transactional versions should be loaded.
 715	 */
 716	tm_enable();
 717	/* Make sure the transaction is marked as failed */
 718	current->thread.tm_texasr |= TEXASR_FS;
 719	/* This loads the checkpointed FP/VEC state, if used */
 720	tm_recheckpoint(&current->thread);
 721
 722	/* This loads the speculative FP/VEC state, if used */
 723	msr_check_and_set(msr & (MSR_FP | MSR_VEC));
 724	if (msr & MSR_FP) {
 725		load_fp_state(&current->thread.fp_state);
 726		regs->msr |= (MSR_FP | current->thread.fpexc_mode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 727	}
 728#ifdef CONFIG_ALTIVEC
 729	if (msr & MSR_VEC) {
 730		load_vr_state(&current->thread.vr_state);
 731		regs->msr |= MSR_VEC;
 732	}
 733#endif
 734
 735	preempt_enable();
 
 
 
 
 
 
 
 736
 737	return 0;
 738}
 739#endif
 740
 741#ifdef CONFIG_PPC64
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 742
 743#define copy_siginfo_to_user	copy_siginfo_to_user32
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 744
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 745#endif /* CONFIG_PPC64 */
 746
 747/*
 748 * Set up a signal frame for a "real-time" signal handler
 749 * (one which gets siginfo).
 750 */
 751int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
 752		       struct task_struct *tsk)
 
 753{
 754	struct rt_sigframe __user *rt_sf;
 755	struct mcontext __user *frame;
 756	struct mcontext __user *tm_frame = NULL;
 757	void __user *addr;
 758	unsigned long newsp = 0;
 759	int sigret;
 760	unsigned long tramp;
 761	struct pt_regs *regs = tsk->thread.regs;
 762#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 763	/* Save the thread's msr before get_tm_stackpointer() changes it */
 764	unsigned long msr = regs->msr;
 765#endif
 766
 767	BUG_ON(tsk != current);
 768
 769	/* Set up Signal Frame */
 770	/* Put a Real Time Context onto stack */
 771	rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
 772	addr = rt_sf;
 773	if (unlikely(rt_sf == NULL))
 774		goto badframe;
 775
 776	/* Put the siginfo & fill in most of the ucontext */
 777	if (copy_siginfo_to_user(&rt_sf->info, &ksig->info)
 778	    || __put_user(0, &rt_sf->uc.uc_flags)
 779	    || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
 
 
 
 
 780	    || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
 781		    &rt_sf->uc.uc_regs)
 782	    || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
 783		goto badframe;
 784
 785	/* Save user registers on the stack */
 786	frame = &rt_sf->uc.uc_mcontext;
 787	addr = frame;
 788	if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
 789		sigret = 0;
 790		tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
 791	} else {
 792		sigret = __NR_rt_sigreturn;
 793		tramp = (unsigned long) frame->tramp;
 794	}
 795
 796#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 797	tm_frame = &rt_sf->uc_transact.uc_mcontext;
 798	if (MSR_TM_ACTIVE(msr)) {
 799		if (__put_user((unsigned long)&rt_sf->uc_transact,
 800			       &rt_sf->uc.uc_link) ||
 801		    __put_user((unsigned long)tm_frame,
 802			       &rt_sf->uc_transact.uc_regs))
 803			goto badframe;
 804		if (save_tm_user_regs(regs, frame, tm_frame, sigret, msr))
 805			goto badframe;
 806	}
 807	else
 808#endif
 809	{
 810		if (__put_user(0, &rt_sf->uc.uc_link))
 811			goto badframe;
 812		if (save_user_regs(regs, frame, tm_frame, sigret, 1))
 813			goto badframe;
 
 814	}
 815	regs->link = tramp;
 816
 817	tsk->thread.fp_state.fpscr = 0;	/* turn off all fp exceptions */
 818
 819	/* create a stack frame for the caller of the handler */
 820	newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
 821	addr = (void __user *)regs->gpr[1];
 822	if (put_user(regs->gpr[1], (u32 __user *)newsp))
 823		goto badframe;
 824
 825	/* Fill registers for signal handler */
 826	regs->gpr[1] = newsp;
 827	regs->gpr[3] = ksig->sig;
 828	regs->gpr[4] = (unsigned long) &rt_sf->info;
 829	regs->gpr[5] = (unsigned long) &rt_sf->uc;
 830	regs->gpr[6] = (unsigned long) rt_sf;
 831	regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
 832	/* enter the signal handler in native-endian mode */
 833	regs->msr &= ~MSR_LE;
 834	regs->msr |= (MSR_KERNEL & MSR_LE);
 835	return 0;
 836
 837badframe:
 
 
 
 
 838	if (show_unhandled_signals)
 839		printk_ratelimited(KERN_INFO
 840				   "%s[%d]: bad frame in handle_rt_signal32: "
 841				   "%p nip %08lx lr %08lx\n",
 842				   tsk->comm, tsk->pid,
 843				   addr, regs->nip, regs->link);
 844
 845	return 1;
 
 846}
 847
 848static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
 849{
 850	sigset_t set;
 851	struct mcontext __user *mcp;
 852
 853	if (get_sigset_t(&set, &ucp->uc_sigmask))
 854		return -EFAULT;
 855#ifdef CONFIG_PPC64
 856	{
 857		u32 cmcp;
 858
 859		if (__get_user(cmcp, &ucp->uc_regs))
 860			return -EFAULT;
 861		mcp = (struct mcontext __user *)(u64)cmcp;
 862		/* no need to check access_ok(mcp), since mcp < 4GB */
 863	}
 864#else
 865	if (__get_user(mcp, &ucp->uc_regs))
 866		return -EFAULT;
 867	if (!access_ok(mcp, sizeof(*mcp)))
 868		return -EFAULT;
 869#endif
 870	set_current_blocked(&set);
 871	if (restore_user_regs(regs, mcp, sig))
 872		return -EFAULT;
 873
 874	return 0;
 875}
 876
 877#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 878static int do_setcontext_tm(struct ucontext __user *ucp,
 879			    struct ucontext __user *tm_ucp,
 880			    struct pt_regs *regs)
 881{
 882	sigset_t set;
 883	struct mcontext __user *mcp;
 884	struct mcontext __user *tm_mcp;
 885	u32 cmcp;
 886	u32 tm_cmcp;
 887
 888	if (get_sigset_t(&set, &ucp->uc_sigmask))
 889		return -EFAULT;
 890
 891	if (__get_user(cmcp, &ucp->uc_regs) ||
 892	    __get_user(tm_cmcp, &tm_ucp->uc_regs))
 893		return -EFAULT;
 894	mcp = (struct mcontext __user *)(u64)cmcp;
 895	tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
 896	/* no need to check access_ok(mcp), since mcp < 4GB */
 897
 898	set_current_blocked(&set);
 899	if (restore_tm_user_regs(regs, mcp, tm_mcp))
 900		return -EFAULT;
 901
 902	return 0;
 903}
 904#endif
 905
 906#ifdef CONFIG_PPC64
 907COMPAT_SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
 908		       struct ucontext __user *, new_ctx, int, ctx_size)
 909#else
 910SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
 911		       struct ucontext __user *, new_ctx, long, ctx_size)
 912#endif
 913{
 914	struct pt_regs *regs = current_pt_regs();
 915	int ctx_has_vsx_region = 0;
 916
 917#ifdef CONFIG_PPC64
 918	unsigned long new_msr = 0;
 919
 920	if (new_ctx) {
 921		struct mcontext __user *mcp;
 922		u32 cmcp;
 923
 924		/*
 925		 * Get pointer to the real mcontext.  No need for
 926		 * access_ok since we are dealing with compat
 927		 * pointers.
 928		 */
 929		if (__get_user(cmcp, &new_ctx->uc_regs))
 930			return -EFAULT;
 931		mcp = (struct mcontext __user *)(u64)cmcp;
 932		if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
 933			return -EFAULT;
 934	}
 935	/*
 936	 * Check that the context is not smaller than the original
 937	 * size (with VMX but without VSX)
 938	 */
 939	if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
 940		return -EINVAL;
 941	/*
 942	 * If the new context state sets the MSR VSX bits but
 943	 * it doesn't provide VSX state.
 944	 */
 945	if ((ctx_size < sizeof(struct ucontext)) &&
 946	    (new_msr & MSR_VSX))
 947		return -EINVAL;
 948	/* Does the context have enough room to store VSX data? */
 949	if (ctx_size >= sizeof(struct ucontext))
 950		ctx_has_vsx_region = 1;
 951#else
 952	/* Context size is for future use. Right now, we only make sure
 953	 * we are passed something we understand
 954	 */
 955	if (ctx_size < sizeof(struct ucontext))
 956		return -EINVAL;
 957#endif
 958	if (old_ctx != NULL) {
 959		struct mcontext __user *mctx;
 960
 961		/*
 962		 * old_ctx might not be 16-byte aligned, in which
 963		 * case old_ctx->uc_mcontext won't be either.
 964		 * Because we have the old_ctx->uc_pad2 field
 965		 * before old_ctx->uc_mcontext, we need to round down
 966		 * from &old_ctx->uc_mcontext to a 16-byte boundary.
 967		 */
 968		mctx = (struct mcontext __user *)
 969			((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
 970		if (!access_ok(old_ctx, ctx_size)
 971		    || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
 972		    || put_sigset_t(&old_ctx->uc_sigmask, &current->blocked)
 973		    || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
 974			return -EFAULT;
 975	}
 976	if (new_ctx == NULL)
 977		return 0;
 978	if (!access_ok(new_ctx, ctx_size) ||
 979	    fault_in_pages_readable((u8 __user *)new_ctx, ctx_size))
 
 980		return -EFAULT;
 981
 982	/*
 983	 * If we get a fault copying the context into the kernel's
 984	 * image of the user's registers, we can't just return -EFAULT
 985	 * because the user's registers will be corrupted.  For instance
 986	 * the NIP value may have been updated but not some of the
 987	 * other registers.  Given that we have done the access_ok
 988	 * and successfully read the first and last bytes of the region
 989	 * above, this should only happen in an out-of-memory situation
 990	 * or if another thread unmaps the region containing the context.
 991	 * We kill the task with a SIGSEGV in this situation.
 992	 */
 993	if (do_setcontext(new_ctx, regs, 0))
 994		do_exit(SIGSEGV);
 995
 996	set_thread_flag(TIF_RESTOREALL);
 997	return 0;
 998}
 999
1000#ifdef CONFIG_PPC64
1001COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
1002#else
1003SYSCALL_DEFINE0(rt_sigreturn)
1004#endif
1005{
1006	struct rt_sigframe __user *rt_sf;
1007	struct pt_regs *regs = current_pt_regs();
1008	int tm_restore = 0;
1009#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1010	struct ucontext __user *uc_transact;
1011	unsigned long msr_hi;
1012	unsigned long tmp;
1013#endif
1014	/* Always make any pending restarted system calls return -EINTR */
1015	current->restart_block.fn = do_no_restart_syscall;
1016
1017	rt_sf = (struct rt_sigframe __user *)
1018		(regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1019	if (!access_ok(rt_sf, sizeof(*rt_sf)))
1020		goto bad;
1021
1022#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1023	/*
1024	 * If there is a transactional state then throw it away.
1025	 * The purpose of a sigreturn is to destroy all traces of the
1026	 * signal frame, this includes any transactional state created
1027	 * within in. We only check for suspended as we can never be
1028	 * active in the kernel, we are active, there is nothing better to
1029	 * do than go ahead and Bad Thing later.
1030	 * The cause is not important as there will never be a
1031	 * recheckpoint so it's not user visible.
1032	 */
1033	if (MSR_TM_SUSPENDED(mfmsr()))
1034		tm_reclaim_current(0);
1035
1036	if (__get_user(tmp, &rt_sf->uc.uc_link))
1037		goto bad;
1038	uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1039	if (uc_transact) {
1040		u32 cmcp;
1041		struct mcontext __user *mcp;
1042
1043		if (__get_user(cmcp, &uc_transact->uc_regs))
1044			return -EFAULT;
1045		mcp = (struct mcontext __user *)(u64)cmcp;
1046		/* The top 32 bits of the MSR are stashed in the transactional
1047		 * ucontext. */
1048		if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1049			goto bad;
1050
1051		if (MSR_TM_ACTIVE(msr_hi<<32)) {
1052			/* Trying to start TM on non TM system */
1053			if (!cpu_has_feature(CPU_FTR_TM))
1054				goto bad;
1055			/* We only recheckpoint on return if we're
1056			 * transaction.
1057			 */
1058			tm_restore = 1;
1059			if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1060				goto bad;
1061		}
1062	}
1063	if (!tm_restore) {
1064		/*
1065		 * Unset regs->msr because ucontext MSR TS is not
1066		 * set, and recheckpoint was not called. This avoid
1067		 * hitting a TM Bad thing at RFID
1068		 */
1069		regs->msr &= ~MSR_TS_MASK;
1070	}
1071	/* Fall through, for non-TM restore */
1072#endif
1073	if (!tm_restore)
1074		if (do_setcontext(&rt_sf->uc, regs, 1))
1075			goto bad;
1076
1077	/*
1078	 * It's not clear whether or why it is desirable to save the
1079	 * sigaltstack setting on signal delivery and restore it on
1080	 * signal return.  But other architectures do this and we have
1081	 * always done it up until now so it is probably better not to
1082	 * change it.  -- paulus
1083	 */
1084#ifdef CONFIG_PPC64
1085	if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1086		goto bad;
 
 
 
 
1087#else
1088	if (restore_altstack(&rt_sf->uc.uc_stack))
1089		goto bad;
1090#endif
1091	set_thread_flag(TIF_RESTOREALL);
1092	return 0;
1093
1094 bad:
1095	if (show_unhandled_signals)
1096		printk_ratelimited(KERN_INFO
1097				   "%s[%d]: bad frame in sys_rt_sigreturn: "
1098				   "%p nip %08lx lr %08lx\n",
1099				   current->comm, current->pid,
1100				   rt_sf, regs->nip, regs->link);
1101
1102	force_sig(SIGSEGV);
1103	return 0;
1104}
1105
1106#ifdef CONFIG_PPC32
1107SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
1108			 int, ndbg, struct sig_dbg_op __user *, dbg)
 
 
1109{
1110	struct pt_regs *regs = current_pt_regs();
1111	struct sig_dbg_op op;
1112	int i;
 
1113	unsigned long new_msr = regs->msr;
1114#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1115	unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1116#endif
1117
1118	for (i=0; i<ndbg; i++) {
1119		if (copy_from_user(&op, dbg + i, sizeof(op)))
1120			return -EFAULT;
1121		switch (op.dbg_type) {
1122		case SIG_DBG_SINGLE_STEPPING:
1123#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1124			if (op.dbg_value) {
1125				new_msr |= MSR_DE;
1126				new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1127			} else {
1128				new_dbcr0 &= ~DBCR0_IC;
1129				if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1130						current->thread.debug.dbcr1)) {
1131					new_msr &= ~MSR_DE;
1132					new_dbcr0 &= ~DBCR0_IDM;
1133				}
1134			}
1135#else
1136			if (op.dbg_value)
1137				new_msr |= MSR_SE;
1138			else
1139				new_msr &= ~MSR_SE;
1140#endif
1141			break;
1142		case SIG_DBG_BRANCH_TRACING:
1143#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1144			return -EINVAL;
1145#else
1146			if (op.dbg_value)
1147				new_msr |= MSR_BE;
1148			else
1149				new_msr &= ~MSR_BE;
1150#endif
1151			break;
1152
1153		default:
1154			return -EINVAL;
1155		}
1156	}
1157
1158	/* We wait until here to actually install the values in the
1159	   registers so if we fail in the above loop, it will not
1160	   affect the contents of these registers.  After this point,
1161	   failure is a problem, anyway, and it's very unlikely unless
1162	   the user is really doing something wrong. */
1163	regs->msr = new_msr;
1164#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1165	current->thread.debug.dbcr0 = new_dbcr0;
1166#endif
1167
1168	if (!access_ok(ctx, sizeof(*ctx)) ||
1169	    fault_in_pages_readable((u8 __user *)ctx, sizeof(*ctx)))
 
1170		return -EFAULT;
1171
1172	/*
1173	 * If we get a fault copying the context into the kernel's
1174	 * image of the user's registers, we can't just return -EFAULT
1175	 * because the user's registers will be corrupted.  For instance
1176	 * the NIP value may have been updated but not some of the
1177	 * other registers.  Given that we have done the access_ok
1178	 * and successfully read the first and last bytes of the region
1179	 * above, this should only happen in an out-of-memory situation
1180	 * or if another thread unmaps the region containing the context.
1181	 * We kill the task with a SIGSEGV in this situation.
1182	 */
1183	if (do_setcontext(ctx, regs, 1)) {
1184		if (show_unhandled_signals)
1185			printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1186					   "sys_debug_setcontext: %p nip %08lx "
1187					   "lr %08lx\n",
1188					   current->comm, current->pid,
1189					   ctx, regs->nip, regs->link);
1190
1191		force_sig(SIGSEGV);
1192		goto out;
1193	}
1194
1195	/*
1196	 * It's not clear whether or why it is desirable to save the
1197	 * sigaltstack setting on signal delivery and restore it on
1198	 * signal return.  But other architectures do this and we have
1199	 * always done it up until now so it is probably better not to
1200	 * change it.  -- paulus
1201	 */
1202	restore_altstack(&ctx->uc_stack);
1203
1204	set_thread_flag(TIF_RESTOREALL);
1205 out:
1206	return 0;
1207}
1208#endif
1209
1210/*
1211 * OK, we're invoking a handler
1212 */
1213int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
1214		struct task_struct *tsk)
1215{
1216	struct sigcontext __user *sc;
1217	struct sigframe __user *frame;
1218	struct mcontext __user *tm_mctx = NULL;
1219	unsigned long newsp = 0;
1220	int sigret;
1221	unsigned long tramp;
1222	struct pt_regs *regs = tsk->thread.regs;
1223#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1224	/* Save the thread's msr before get_tm_stackpointer() changes it */
1225	unsigned long msr = regs->msr;
1226#endif
1227
1228	BUG_ON(tsk != current);
1229
1230	/* Set up Signal Frame */
1231	frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
1232	if (unlikely(frame == NULL))
1233		goto badframe;
1234	sc = (struct sigcontext __user *) &frame->sctx;
1235
1236#if _NSIG != 64
1237#error "Please adjust handle_signal()"
1238#endif
1239	if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
1240	    || __put_user(oldset->sig[0], &sc->oldmask)
1241#ifdef CONFIG_PPC64
1242	    || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1243#else
1244	    || __put_user(oldset->sig[1], &sc->_unused[3])
1245#endif
1246	    || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1247	    || __put_user(ksig->sig, &sc->signal))
1248		goto badframe;
1249
1250	if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
1251		sigret = 0;
1252		tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
1253	} else {
1254		sigret = __NR_sigreturn;
1255		tramp = (unsigned long) frame->mctx.tramp;
1256	}
1257
1258#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1259	tm_mctx = &frame->mctx_transact;
1260	if (MSR_TM_ACTIVE(msr)) {
1261		if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
1262				      sigret, msr))
1263			goto badframe;
1264	}
1265	else
1266#endif
1267	{
1268		if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
1269			goto badframe;
 
1270	}
1271
1272	regs->link = tramp;
1273
1274	tsk->thread.fp_state.fpscr = 0;	/* turn off all fp exceptions */
1275
1276	/* create a stack frame for the caller of the handler */
1277	newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1278	if (put_user(regs->gpr[1], (u32 __user *)newsp))
1279		goto badframe;
1280
1281	regs->gpr[1] = newsp;
1282	regs->gpr[3] = ksig->sig;
1283	regs->gpr[4] = (unsigned long) sc;
1284	regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
1285	/* enter the signal handler in big-endian mode */
1286	regs->msr &= ~MSR_LE;
1287	return 0;
 
1288
1289badframe:
 
 
 
 
1290	if (show_unhandled_signals)
1291		printk_ratelimited(KERN_INFO
1292				   "%s[%d]: bad frame in handle_signal32: "
1293				   "%p nip %08lx lr %08lx\n",
1294				   tsk->comm, tsk->pid,
1295				   frame, regs->nip, regs->link);
1296
1297	return 1;
 
1298}
1299
1300/*
1301 * Do a signal return; undo the signal stack.
1302 */
1303#ifdef CONFIG_PPC64
1304COMPAT_SYSCALL_DEFINE0(sigreturn)
1305#else
1306SYSCALL_DEFINE0(sigreturn)
1307#endif
1308{
1309	struct pt_regs *regs = current_pt_regs();
1310	struct sigframe __user *sf;
1311	struct sigcontext __user *sc;
1312	struct sigcontext sigctx;
1313	struct mcontext __user *sr;
1314	void __user *addr;
1315	sigset_t set;
1316#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1317	struct mcontext __user *mcp, *tm_mcp;
1318	unsigned long msr_hi;
1319#endif
1320
1321	/* Always make any pending restarted system calls return -EINTR */
1322	current->restart_block.fn = do_no_restart_syscall;
1323
1324	sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1325	sc = &sf->sctx;
1326	addr = sc;
1327	if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1328		goto badframe;
1329
1330#ifdef CONFIG_PPC64
1331	/*
1332	 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1333	 * unused part of the signal stackframe
1334	 */
1335	set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1336#else
1337	set.sig[0] = sigctx.oldmask;
1338	set.sig[1] = sigctx._unused[3];
1339#endif
1340	set_current_blocked(&set);
1341
1342#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1343	mcp = (struct mcontext __user *)&sf->mctx;
1344	tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1345	if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1346		goto badframe;
1347	if (MSR_TM_ACTIVE(msr_hi<<32)) {
1348		if (!cpu_has_feature(CPU_FTR_TM))
1349			goto badframe;
1350		if (restore_tm_user_regs(regs, mcp, tm_mcp))
1351			goto badframe;
1352	} else
1353#endif
1354	{
1355		sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1356		addr = sr;
1357		if (!access_ok(sr, sizeof(*sr))
1358		    || restore_user_regs(regs, sr, 1))
1359			goto badframe;
1360	}
1361
1362	set_thread_flag(TIF_RESTOREALL);
1363	return 0;
1364
1365badframe:
1366	if (show_unhandled_signals)
1367		printk_ratelimited(KERN_INFO
1368				   "%s[%d]: bad frame in sys_sigreturn: "
1369				   "%p nip %08lx lr %08lx\n",
1370				   current->comm, current->pid,
1371				   addr, regs->nip, regs->link);
1372
1373	force_sig(SIGSEGV);
1374	return 0;
1375}
v3.1
 
   1/*
   2 * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
   3 *
   4 *  PowerPC version
   5 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   6 * Copyright (C) 2001 IBM
   7 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   8 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
   9 *
  10 *  Derived from "arch/i386/kernel/signal.c"
  11 *    Copyright (C) 1991, 1992 Linus Torvalds
  12 *    1997-11-28  Modified for POSIX.1b signals by Richard Henderson
  13 *
  14 *  This program is free software; you can redistribute it and/or
  15 *  modify it under the terms of the GNU General Public License
  16 *  as published by the Free Software Foundation; either version
  17 *  2 of the License, or (at your option) any later version.
  18 */
  19
  20#include <linux/sched.h>
  21#include <linux/mm.h>
  22#include <linux/smp.h>
  23#include <linux/kernel.h>
  24#include <linux/signal.h>
  25#include <linux/errno.h>
  26#include <linux/elf.h>
  27#include <linux/ptrace.h>
 
  28#include <linux/ratelimit.h>
 
  29#ifdef CONFIG_PPC64
  30#include <linux/syscalls.h>
  31#include <linux/compat.h>
  32#else
  33#include <linux/wait.h>
  34#include <linux/unistd.h>
  35#include <linux/stddef.h>
  36#include <linux/tty.h>
  37#include <linux/binfmts.h>
  38#include <linux/freezer.h>
  39#endif
  40
  41#include <asm/uaccess.h>
  42#include <asm/cacheflush.h>
  43#include <asm/syscalls.h>
  44#include <asm/sigcontext.h>
  45#include <asm/vdso.h>
 
 
 
  46#ifdef CONFIG_PPC64
  47#include "ppc32.h"
  48#include <asm/unistd.h>
  49#else
  50#include <asm/ucontext.h>
  51#include <asm/pgtable.h>
  52#endif
  53
  54#include "signal.h"
  55
  56#undef DEBUG_SIG
  57
  58#ifdef CONFIG_PPC64
  59#define sys_sigsuspend	compat_sys_sigsuspend
  60#define sys_rt_sigsuspend	compat_sys_rt_sigsuspend
  61#define sys_rt_sigreturn	compat_sys_rt_sigreturn
  62#define sys_sigaction	compat_sys_sigaction
  63#define sys_swapcontext	compat_sys_swapcontext
  64#define sys_sigreturn	compat_sys_sigreturn
  65
  66#define old_sigaction	old_sigaction32
  67#define sigcontext	sigcontext32
  68#define mcontext	mcontext32
  69#define ucontext	ucontext32
  70
 
 
  71/*
  72 * Userspace code may pass a ucontext which doesn't include VSX added
  73 * at the end.  We need to check for this case.
  74 */
  75#define UCONTEXTSIZEWITHOUTVSX \
  76		(sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
  77
  78/*
  79 * Returning 0 means we return to userspace via
  80 * ret_from_except and thus restore all user
  81 * registers from *regs.  This is what we need
  82 * to do when a signal has been delivered.
  83 */
  84
  85#define GP_REGS_SIZE	min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
  86#undef __SIGNAL_FRAMESIZE
  87#define __SIGNAL_FRAMESIZE	__SIGNAL_FRAMESIZE32
  88#undef ELF_NVRREG
  89#define ELF_NVRREG	ELF_NVRREG32
  90
  91/*
  92 * Functions for flipping sigsets (thanks to brain dead generic
  93 * implementation that makes things simple for little endian only)
  94 */
  95static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
  96{
  97	compat_sigset_t	cset;
  98
  99	switch (_NSIG_WORDS) {
 100	case 4: cset.sig[5] = set->sig[3] & 0xffffffffull;
 101		cset.sig[7] = set->sig[3] >> 32;
 102	case 3: cset.sig[4] = set->sig[2] & 0xffffffffull;
 103		cset.sig[5] = set->sig[2] >> 32;
 104	case 2: cset.sig[2] = set->sig[1] & 0xffffffffull;
 105		cset.sig[3] = set->sig[1] >> 32;
 106	case 1: cset.sig[0] = set->sig[0] & 0xffffffffull;
 107		cset.sig[1] = set->sig[0] >> 32;
 108	}
 109	return copy_to_user(uset, &cset, sizeof(*uset));
 110}
 111
 112static inline int get_sigset_t(sigset_t *set,
 113			       const compat_sigset_t __user *uset)
 114{
 115	compat_sigset_t s32;
 116
 117	if (copy_from_user(&s32, uset, sizeof(*uset)))
 118		return -EFAULT;
 119
 120	/*
 121	 * Swap the 2 words of the 64-bit sigset_t (they are stored
 122	 * in the "wrong" endian in 32-bit user storage).
 123	 */
 124	switch (_NSIG_WORDS) {
 125	case 4: set->sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
 126	case 3: set->sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
 127	case 2: set->sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
 128	case 1: set->sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
 129	}
 130	return 0;
 131}
 132
 133static inline int get_old_sigaction(struct k_sigaction *new_ka,
 134		struct old_sigaction __user *act)
 135{
 136	compat_old_sigset_t mask;
 137	compat_uptr_t handler, restorer;
 138
 139	if (get_user(handler, &act->sa_handler) ||
 140	    __get_user(restorer, &act->sa_restorer) ||
 141	    __get_user(new_ka->sa.sa_flags, &act->sa_flags) ||
 142	    __get_user(mask, &act->sa_mask))
 143		return -EFAULT;
 144	new_ka->sa.sa_handler = compat_ptr(handler);
 145	new_ka->sa.sa_restorer = compat_ptr(restorer);
 146	siginitset(&new_ka->sa.sa_mask, mask);
 147	return 0;
 148}
 149
 150#define to_user_ptr(p)		ptr_to_compat(p)
 151#define from_user_ptr(p)	compat_ptr(p)
 152
 153static inline int save_general_regs(struct pt_regs *regs,
 154		struct mcontext __user *frame)
 155{
 156	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
 157	int i;
 158
 159	WARN_ON(!FULL_REGS(regs));
 160
 161	for (i = 0; i <= PT_RESULT; i ++) {
 162		if (i == 14 && !FULL_REGS(regs))
 163			i = 32;
 164		if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
 
 
 
 
 165			return -EFAULT;
 166	}
 167	return 0;
 168}
 169
 170static inline int restore_general_regs(struct pt_regs *regs,
 171		struct mcontext __user *sr)
 172{
 173	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
 174	int i;
 175
 176	for (i = 0; i <= PT_RESULT; i++) {
 177		if ((i == PT_MSR) || (i == PT_SOFTE))
 178			continue;
 179		if (__get_user(gregs[i], &sr->mc_gregs[i]))
 180			return -EFAULT;
 181	}
 182	return 0;
 183}
 184
 185#else /* CONFIG_PPC64 */
 186
 187#define GP_REGS_SIZE	min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
 188
 189static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
 190{
 191	return copy_to_user(uset, set, sizeof(*uset));
 192}
 193
 194static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
 195{
 196	return copy_from_user(set, uset, sizeof(*uset));
 197}
 198
 199static inline int get_old_sigaction(struct k_sigaction *new_ka,
 200		struct old_sigaction __user *act)
 201{
 202	old_sigset_t mask;
 203
 204	if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
 205			__get_user(new_ka->sa.sa_handler, &act->sa_handler) ||
 206			__get_user(new_ka->sa.sa_restorer, &act->sa_restorer))
 207		return -EFAULT;
 208	__get_user(new_ka->sa.sa_flags, &act->sa_flags);
 209	__get_user(mask, &act->sa_mask);
 210	siginitset(&new_ka->sa.sa_mask, mask);
 211	return 0;
 212}
 213
 214#define to_user_ptr(p)		((unsigned long)(p))
 215#define from_user_ptr(p)	((void __user *)(p))
 216
 217static inline int save_general_regs(struct pt_regs *regs,
 218		struct mcontext __user *frame)
 219{
 220	WARN_ON(!FULL_REGS(regs));
 221	return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
 222}
 223
 224static inline int restore_general_regs(struct pt_regs *regs,
 225		struct mcontext __user *sr)
 226{
 227	/* copy up to but not including MSR */
 228	if (__copy_from_user(regs, &sr->mc_gregs,
 229				PT_MSR * sizeof(elf_greg_t)))
 230		return -EFAULT;
 231	/* copy from orig_r3 (the word after the MSR) up to the end */
 232	if (__copy_from_user(&regs->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
 233				GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
 234		return -EFAULT;
 235	return 0;
 236}
 237
 238#endif /* CONFIG_PPC64 */
 239
 240/*
 241 * Atomically swap in the new signal mask, and wait for a signal.
 242 */
 243long sys_sigsuspend(old_sigset_t mask)
 244{
 245	mask &= _BLOCKABLE;
 246	spin_lock_irq(&current->sighand->siglock);
 247	current->saved_sigmask = current->blocked;
 248	siginitset(&current->blocked, mask);
 249	recalc_sigpending();
 250	spin_unlock_irq(&current->sighand->siglock);
 251
 252 	current->state = TASK_INTERRUPTIBLE;
 253 	schedule();
 254	set_restore_sigmask();
 255 	return -ERESTARTNOHAND;
 256}
 257
 258long sys_sigaction(int sig, struct old_sigaction __user *act,
 259		struct old_sigaction __user *oact)
 260{
 261	struct k_sigaction new_ka, old_ka;
 262	int ret;
 263
 264#ifdef CONFIG_PPC64
 265	if (sig < 0)
 266		sig = -sig;
 267#endif
 268
 269	if (act) {
 270		if (get_old_sigaction(&new_ka, act))
 271			return -EFAULT;
 272	}
 273
 274	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 275	if (!ret && oact) {
 276		if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
 277		    __put_user(to_user_ptr(old_ka.sa.sa_handler),
 278			    &oact->sa_handler) ||
 279		    __put_user(to_user_ptr(old_ka.sa.sa_restorer),
 280			    &oact->sa_restorer) ||
 281		    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
 282		    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
 283			return -EFAULT;
 284	}
 285
 286	return ret;
 287}
 288
 289/*
 290 * When we have signals to deliver, we set up on the
 291 * user stack, going down from the original stack pointer:
 292 *	an ABI gap of 56 words
 293 *	an mcontext struct
 294 *	a sigcontext struct
 295 *	a gap of __SIGNAL_FRAMESIZE bytes
 296 *
 297 * Each of these things must be a multiple of 16 bytes in size. The following
 298 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
 299 *
 300 */
 301struct sigframe {
 302	struct sigcontext sctx;		/* the sigcontext */
 303	struct mcontext	mctx;		/* all the register values */
 
 
 
 
 304	/*
 305	 * Programs using the rs6000/xcoff abi can save up to 19 gp
 306	 * regs and 18 fp regs below sp before decrementing it.
 307	 */
 308	int			abigap[56];
 309};
 310
 311/* We use the mc_pad field for the signal return trampoline. */
 312#define tramp	mc_pad
 313
 314/*
 315 *  When we have rt signals to deliver, we set up on the
 316 *  user stack, going down from the original stack pointer:
 317 *	one rt_sigframe struct (siginfo + ucontext + ABI gap)
 318 *	a gap of __SIGNAL_FRAMESIZE+16 bytes
 319 *  (the +16 is to get the siginfo and ucontext in the same
 320 *  positions as in older kernels).
 321 *
 322 *  Each of these things must be a multiple of 16 bytes in size.
 323 *
 324 */
 325struct rt_sigframe {
 326#ifdef CONFIG_PPC64
 327	compat_siginfo_t info;
 328#else
 329	struct siginfo info;
 330#endif
 331	struct ucontext	uc;
 
 
 
 332	/*
 333	 * Programs using the rs6000/xcoff abi can save up to 19 gp
 334	 * regs and 18 fp regs below sp before decrementing it.
 335	 */
 336	int			abigap[56];
 337};
 338
 339#ifdef CONFIG_VSX
 340unsigned long copy_fpr_to_user(void __user *to,
 341			       struct task_struct *task)
 342{
 343	double buf[ELF_NFPREG];
 344	int i;
 345
 346	/* save FPR copy to local buffer then write to the thread_struct */
 347	for (i = 0; i < (ELF_NFPREG - 1) ; i++)
 348		buf[i] = task->thread.TS_FPR(i);
 349	memcpy(&buf[i], &task->thread.fpscr, sizeof(double));
 350	return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
 351}
 352
 353unsigned long copy_fpr_from_user(struct task_struct *task,
 354				 void __user *from)
 355{
 356	double buf[ELF_NFPREG];
 357	int i;
 358
 359	if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
 360		return 1;
 361	for (i = 0; i < (ELF_NFPREG - 1) ; i++)
 362		task->thread.TS_FPR(i) = buf[i];
 363	memcpy(&task->thread.fpscr, &buf[i], sizeof(double));
 364
 365	return 0;
 366}
 367
 368unsigned long copy_vsx_to_user(void __user *to,
 369			       struct task_struct *task)
 370{
 371	double buf[ELF_NVSRHALFREG];
 372	int i;
 373
 374	/* save FPR copy to local buffer then write to the thread_struct */
 375	for (i = 0; i < ELF_NVSRHALFREG; i++)
 376		buf[i] = task->thread.fpr[i][TS_VSRLOWOFFSET];
 377	return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
 378}
 379
 380unsigned long copy_vsx_from_user(struct task_struct *task,
 381				 void __user *from)
 382{
 383	double buf[ELF_NVSRHALFREG];
 384	int i;
 385
 386	if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
 387		return 1;
 388	for (i = 0; i < ELF_NVSRHALFREG ; i++)
 389		task->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];
 390	return 0;
 391}
 392#else
 393inline unsigned long copy_fpr_to_user(void __user *to,
 394				      struct task_struct *task)
 395{
 396	return __copy_to_user(to, task->thread.fpr,
 397			      ELF_NFPREG * sizeof(double));
 398}
 399
 400inline unsigned long copy_fpr_from_user(struct task_struct *task,
 401					void __user *from)
 402{
 403	return __copy_from_user(task->thread.fpr, from,
 404			      ELF_NFPREG * sizeof(double));
 405}
 406#endif
 407
 408/*
 409 * Save the current user registers on the user stack.
 410 * We only save the altivec/spe registers if the process has used
 411 * altivec/spe instructions at some point.
 412 */
 413static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
 414		int sigret, int ctx_has_vsx_region)
 
 415{
 416	unsigned long msr = regs->msr;
 417
 418	/* Make sure floating point registers are stored in regs */
 419	flush_fp_to_thread(current);
 420
 421	/* save general registers */
 422	if (save_general_regs(regs, frame))
 423		return 1;
 424
 425#ifdef CONFIG_ALTIVEC
 426	/* save altivec registers */
 427	if (current->thread.used_vr) {
 428		flush_altivec_to_thread(current);
 429		if (__copy_to_user(&frame->mc_vregs, current->thread.vr,
 430				   ELF_NVRREG * sizeof(vector128)))
 431			return 1;
 432		/* set MSR_VEC in the saved MSR value to indicate that
 433		   frame->mc_vregs contains valid data */
 434		msr |= MSR_VEC;
 435	}
 436	/* else assert((regs->msr & MSR_VEC) == 0) */
 437
 438	/* We always copy to/from vrsave, it's 0 if we don't have or don't
 439	 * use altivec. Since VSCR only contains 32 bits saved in the least
 440	 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
 441	 * most significant bits of that same vector. --BenH
 
 442	 */
 
 
 443	if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
 444		return 1;
 445#endif /* CONFIG_ALTIVEC */
 446	if (copy_fpr_to_user(&frame->mc_fregs, current))
 447		return 1;
 
 
 
 
 
 
 448#ifdef CONFIG_VSX
 449	/*
 450	 * Copy VSR 0-31 upper half from thread_struct to local
 451	 * buffer, then write that to userspace.  Also set MSR_VSX in
 452	 * the saved MSR value to indicate that frame->mc_vregs
 453	 * contains valid data
 454	 */
 455	if (current->thread.used_vsr && ctx_has_vsx_region) {
 456		__giveup_vsx(current);
 457		if (copy_vsx_to_user(&frame->mc_vsregs, current))
 458			return 1;
 459		msr |= MSR_VSX;
 460	}
 461#endif /* CONFIG_VSX */
 462#ifdef CONFIG_SPE
 463	/* save spe registers */
 464	if (current->thread.used_spe) {
 465		flush_spe_to_thread(current);
 466		if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
 467				   ELF_NEVRREG * sizeof(u32)))
 468			return 1;
 469		/* set MSR_SPE in the saved MSR value to indicate that
 470		   frame->mc_vregs contains valid data */
 471		msr |= MSR_SPE;
 472	}
 473	/* else assert((regs->msr & MSR_SPE) == 0) */
 474
 475	/* We always copy to/from spefscr */
 476	if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
 477		return 1;
 478#endif /* CONFIG_SPE */
 479
 480	if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
 481		return 1;
 
 
 
 
 
 
 482	if (sigret) {
 483		/* Set up the sigreturn trampoline: li r0,sigret; sc */
 484		if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
 485		    || __put_user(0x44000002UL, &frame->tramp[1]))
 486			return 1;
 487		flush_icache_range((unsigned long) &frame->tramp[0],
 488				   (unsigned long) &frame->tramp[2]);
 489	}
 490
 491	return 0;
 492}
 493
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 494/*
 495 * Restore the current user register values from the user stack,
 496 * (except for MSR).
 497 */
 498static long restore_user_regs(struct pt_regs *regs,
 499			      struct mcontext __user *sr, int sig)
 500{
 501	long err;
 502	unsigned int save_r2 = 0;
 503	unsigned long msr;
 504#ifdef CONFIG_VSX
 505	int i;
 506#endif
 507
 508	/*
 509	 * restore general registers but not including MSR or SOFTE. Also
 510	 * take care of keeping r2 (TLS) intact if not a signal
 511	 */
 512	if (!sig)
 513		save_r2 = (unsigned int)regs->gpr[2];
 514	err = restore_general_regs(regs, sr);
 515	regs->trap = 0;
 516	err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
 517	if (!sig)
 518		regs->gpr[2] = (unsigned long) save_r2;
 519	if (err)
 520		return 1;
 521
 522	/* if doing signal return, restore the previous little-endian mode */
 523	if (sig)
 524		regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
 525
 526	/*
 527	 * Do this before updating the thread state in
 528	 * current->thread.fpr/vr/evr.  That way, if we get preempted
 529	 * and another task grabs the FPU/Altivec/SPE, it won't be
 530	 * tempted to save the current CPU state into the thread_struct
 531	 * and corrupt what we are writing there.
 532	 */
 533	discard_lazy_cpu_state();
 534
 535#ifdef CONFIG_ALTIVEC
 536	/*
 537	 * Force the process to reload the altivec registers from
 538	 * current->thread when it next does altivec instructions
 539	 */
 540	regs->msr &= ~MSR_VEC;
 541	if (msr & MSR_VEC) {
 542		/* restore altivec registers from the stack */
 543		if (__copy_from_user(current->thread.vr, &sr->mc_vregs,
 544				     sizeof(sr->mc_vregs)))
 545			return 1;
 
 546	} else if (current->thread.used_vr)
 547		memset(current->thread.vr, 0, ELF_NVRREG * sizeof(vector128));
 
 548
 549	/* Always get VRSAVE back */
 550	if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
 551		return 1;
 
 
 552#endif /* CONFIG_ALTIVEC */
 553	if (copy_fpr_from_user(current, &sr->mc_fregs))
 554		return 1;
 555
 556#ifdef CONFIG_VSX
 557	/*
 558	 * Force the process to reload the VSX registers from
 559	 * current->thread when it next does VSX instruction.
 560	 */
 561	regs->msr &= ~MSR_VSX;
 562	if (msr & MSR_VSX) {
 563		/*
 564		 * Restore altivec registers from the stack to a local
 565		 * buffer, then write this out to the thread_struct
 566		 */
 567		if (copy_vsx_from_user(current, &sr->mc_vsregs))
 568			return 1;
 
 569	} else if (current->thread.used_vsr)
 570		for (i = 0; i < 32 ; i++)
 571			current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;
 572#endif /* CONFIG_VSX */
 573	/*
 574	 * force the process to reload the FP registers from
 575	 * current->thread when it next does FP instructions
 576	 */
 577	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
 578
 579#ifdef CONFIG_SPE
 580	/* force the process to reload the spe registers from
 581	   current->thread when it next does spe instructions */
 582	regs->msr &= ~MSR_SPE;
 583	if (msr & MSR_SPE) {
 584		/* restore spe registers from the stack */
 585		if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
 586				     ELF_NEVRREG * sizeof(u32)))
 587			return 1;
 
 588	} else if (current->thread.used_spe)
 589		memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
 590
 591	/* Always get SPEFSCR back */
 592	if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
 593		return 1;
 594#endif /* CONFIG_SPE */
 595
 596	return 0;
 597}
 598
 599#ifdef CONFIG_PPC64
 600long compat_sys_rt_sigaction(int sig, const struct sigaction32 __user *act,
 601		struct sigaction32 __user *oact, size_t sigsetsize)
 
 
 
 
 
 
 602{
 603	struct k_sigaction new_ka, old_ka;
 604	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 605
 606	/* XXX: Don't preclude handling different sized sigset_t's.  */
 607	if (sigsetsize != sizeof(compat_sigset_t))
 608		return -EINVAL;
 
 
 609
 610	if (act) {
 611		compat_uptr_t handler;
 612
 613		ret = get_user(handler, &act->sa_handler);
 614		new_ka.sa.sa_handler = compat_ptr(handler);
 615		ret |= get_sigset_t(&new_ka.sa.sa_mask, &act->sa_mask);
 616		ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
 617		if (ret)
 618			return -EFAULT;
 
 
 
 
 
 
 
 
 
 
 619	}
 620
 621	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 622	if (!ret && oact) {
 623		ret = put_user(to_user_ptr(old_ka.sa.sa_handler), &oact->sa_handler);
 624		ret |= put_sigset_t(&oact->sa_mask, &old_ka.sa.sa_mask);
 625		ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
 626	}
 627	return ret;
 628}
 
 629
 630/*
 631 * Note: it is necessary to treat how as an unsigned int, with the
 632 * corresponding cast to a signed int to insure that the proper
 633 * conversion (sign extension) between the register representation
 634 * of a signed int (msr in 32-bit mode) and the register representation
 635 * of a signed int (msr in 64-bit mode) is performed.
 636 */
 637long compat_sys_rt_sigprocmask(u32 how, compat_sigset_t __user *set,
 638		compat_sigset_t __user *oset, size_t sigsetsize)
 639{
 640	sigset_t s;
 641	sigset_t __user *up;
 642	int ret;
 643	mm_segment_t old_fs = get_fs();
 644
 645	if (set) {
 646		if (get_sigset_t(&s, set))
 647			return -EFAULT;
 648	}
 649
 650	set_fs(KERNEL_DS);
 651	/* This is valid because of the set_fs() */
 652	up = (sigset_t __user *) &s;
 653	ret = sys_rt_sigprocmask((int)how, set ? up : NULL, oset ? up : NULL,
 654				 sigsetsize);
 655	set_fs(old_fs);
 656	if (ret)
 657		return ret;
 658	if (oset) {
 659		if (put_sigset_t(oset, &s))
 660			return -EFAULT;
 661	}
 662	return 0;
 663}
 
 
 
 664
 665long compat_sys_rt_sigpending(compat_sigset_t __user *set, compat_size_t sigsetsize)
 666{
 667	sigset_t s;
 668	int ret;
 669	mm_segment_t old_fs = get_fs();
 670
 671	set_fs(KERNEL_DS);
 672	/* The __user pointer cast is valid because of the set_fs() */
 673	ret = sys_rt_sigpending((sigset_t __user *) &s, sigsetsize);
 674	set_fs(old_fs);
 675	if (!ret) {
 676		if (put_sigset_t(set, &s))
 677			return -EFAULT;
 678	}
 679	return ret;
 680}
 681
 
 
 
 
 
 682
 683int copy_siginfo_to_user32(struct compat_siginfo __user *d, siginfo_t *s)
 684{
 685	int err;
 
 
 
 
 686
 687	if (!access_ok (VERIFY_WRITE, d, sizeof(*d)))
 688		return -EFAULT;
 
 
 
 689
 690	/* If you change siginfo_t structure, please be sure
 691	 * this code is fixed accordingly.
 692	 * It should never copy any pad contained in the structure
 693	 * to avoid security leaks, but must copy the generic
 694	 * 3 ints plus the relevant union member.
 695	 * This routine must convert siginfo from 64bit to 32bit as well
 696	 * at the same time.
 697	 */
 698	err = __put_user(s->si_signo, &d->si_signo);
 699	err |= __put_user(s->si_errno, &d->si_errno);
 700	err |= __put_user((short)s->si_code, &d->si_code);
 701	if (s->si_code < 0)
 702		err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad,
 703				      SI_PAD_SIZE32);
 704	else switch(s->si_code >> 16) {
 705	case __SI_CHLD >> 16:
 706		err |= __put_user(s->si_pid, &d->si_pid);
 707		err |= __put_user(s->si_uid, &d->si_uid);
 708		err |= __put_user(s->si_utime, &d->si_utime);
 709		err |= __put_user(s->si_stime, &d->si_stime);
 710		err |= __put_user(s->si_status, &d->si_status);
 711		break;
 712	case __SI_FAULT >> 16:
 713		err |= __put_user((unsigned int)(unsigned long)s->si_addr,
 714				  &d->si_addr);
 715		break;
 716	case __SI_POLL >> 16:
 717		err |= __put_user(s->si_band, &d->si_band);
 718		err |= __put_user(s->si_fd, &d->si_fd);
 719		break;
 720	case __SI_TIMER >> 16:
 721		err |= __put_user(s->si_tid, &d->si_tid);
 722		err |= __put_user(s->si_overrun, &d->si_overrun);
 723		err |= __put_user(s->si_int, &d->si_int);
 724		break;
 725	case __SI_RT >> 16: /* This is not generated by the kernel as of now.  */
 726	case __SI_MESGQ >> 16:
 727		err |= __put_user(s->si_int, &d->si_int);
 728		/* fallthrough */
 729	case __SI_KILL >> 16:
 730	default:
 731		err |= __put_user(s->si_pid, &d->si_pid);
 732		err |= __put_user(s->si_uid, &d->si_uid);
 733		break;
 734	}
 735	return err;
 736}
 737
 738#define copy_siginfo_to_user	copy_siginfo_to_user32
 
 
 739
 740int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from)
 741{
 742	memset(to, 0, sizeof *to);
 743
 744	if (copy_from_user(to, from, 3*sizeof(int)) ||
 745	    copy_from_user(to->_sifields._pad,
 746			   from->_sifields._pad, SI_PAD_SIZE32))
 747		return -EFAULT;
 748
 749	return 0;
 750}
 
 751
 752/*
 753 * Note: it is necessary to treat pid and sig as unsigned ints, with the
 754 * corresponding cast to a signed int to insure that the proper conversion
 755 * (sign extension) between the register representation of a signed int
 756 * (msr in 32-bit mode) and the register representation of a signed int
 757 * (msr in 64-bit mode) is performed.
 758 */
 759long compat_sys_rt_sigqueueinfo(u32 pid, u32 sig, compat_siginfo_t __user *uinfo)
 760{
 761	siginfo_t info;
 762	int ret;
 763	mm_segment_t old_fs = get_fs();
 764
 765	ret = copy_siginfo_from_user32(&info, uinfo);
 766	if (unlikely(ret))
 767		return ret;
 768
 769	set_fs (KERNEL_DS);
 770	/* The __user pointer cast is valid becasuse of the set_fs() */
 771	ret = sys_rt_sigqueueinfo((int)pid, (int)sig, (siginfo_t __user *) &info);
 772	set_fs (old_fs);
 773	return ret;
 774}
 775/*
 776 *  Start Alternate signal stack support
 777 *
 778 *  System Calls
 779 *       sigaltatck               compat_sys_sigaltstack
 780 */
 781
 782int compat_sys_sigaltstack(u32 __new, u32 __old, int r5,
 783		      int r6, int r7, int r8, struct pt_regs *regs)
 784{
 785	stack_32_t __user * newstack = compat_ptr(__new);
 786	stack_32_t __user * oldstack = compat_ptr(__old);
 787	stack_t uss, uoss;
 788	int ret;
 789	mm_segment_t old_fs;
 790	unsigned long sp;
 791	compat_uptr_t ss_sp;
 792
 793	/*
 794	 * set sp to the user stack on entry to the system call
 795	 * the system call router sets R9 to the saved registers
 796	 */
 797	sp = regs->gpr[1];
 798
 799	/* Put new stack info in local 64 bit stack struct */
 800	if (newstack) {
 801		if (get_user(ss_sp, &newstack->ss_sp) ||
 802		    __get_user(uss.ss_flags, &newstack->ss_flags) ||
 803		    __get_user(uss.ss_size, &newstack->ss_size))
 804			return -EFAULT;
 805		uss.ss_sp = compat_ptr(ss_sp);
 806	}
 807
 808	old_fs = get_fs();
 809	set_fs(KERNEL_DS);
 810	/* The __user pointer casts are valid because of the set_fs() */
 811	ret = do_sigaltstack(
 812		newstack ? (stack_t __user *) &uss : NULL,
 813		oldstack ? (stack_t __user *) &uoss : NULL,
 814		sp);
 815	set_fs(old_fs);
 816	/* Copy the stack information to the user output buffer */
 817	if (!ret && oldstack  &&
 818		(put_user(ptr_to_compat(uoss.ss_sp), &oldstack->ss_sp) ||
 819		 __put_user(uoss.ss_flags, &oldstack->ss_flags) ||
 820		 __put_user(uoss.ss_size, &oldstack->ss_size)))
 821		return -EFAULT;
 822	return ret;
 823}
 824#endif /* CONFIG_PPC64 */
 825
 826/*
 827 * Set up a signal frame for a "real-time" signal handler
 828 * (one which gets siginfo).
 829 */
 830int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
 831		siginfo_t *info, sigset_t *oldset,
 832		struct pt_regs *regs)
 833{
 834	struct rt_sigframe __user *rt_sf;
 835	struct mcontext __user *frame;
 
 836	void __user *addr;
 837	unsigned long newsp = 0;
 
 
 
 
 
 
 
 
 
 838
 839	/* Set up Signal Frame */
 840	/* Put a Real Time Context onto stack */
 841	rt_sf = get_sigframe(ka, regs, sizeof(*rt_sf), 1);
 842	addr = rt_sf;
 843	if (unlikely(rt_sf == NULL))
 844		goto badframe;
 845
 846	/* Put the siginfo & fill in most of the ucontext */
 847	if (copy_siginfo_to_user(&rt_sf->info, info)
 848	    || __put_user(0, &rt_sf->uc.uc_flags)
 849	    || __put_user(0, &rt_sf->uc.uc_link)
 850	    || __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)
 851	    || __put_user(sas_ss_flags(regs->gpr[1]),
 852			  &rt_sf->uc.uc_stack.ss_flags)
 853	    || __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size)
 854	    || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
 855		    &rt_sf->uc.uc_regs)
 856	    || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
 857		goto badframe;
 858
 859	/* Save user registers on the stack */
 860	frame = &rt_sf->uc.uc_mcontext;
 861	addr = frame;
 862	if (vdso32_rt_sigtramp && current->mm->context.vdso_base) {
 863		if (save_user_regs(regs, frame, 0, 1))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 864			goto badframe;
 865		regs->link = current->mm->context.vdso_base + vdso32_rt_sigtramp;
 866	} else {
 867		if (save_user_regs(regs, frame, __NR_rt_sigreturn, 1))
 
 
 
 
 868			goto badframe;
 869		regs->link = (unsigned long) frame->tramp;
 870	}
 
 871
 872	current->thread.fpscr.val = 0;	/* turn off all fp exceptions */
 873
 874	/* create a stack frame for the caller of the handler */
 875	newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
 876	addr = (void __user *)regs->gpr[1];
 877	if (put_user(regs->gpr[1], (u32 __user *)newsp))
 878		goto badframe;
 879
 880	/* Fill registers for signal handler */
 881	regs->gpr[1] = newsp;
 882	regs->gpr[3] = sig;
 883	regs->gpr[4] = (unsigned long) &rt_sf->info;
 884	regs->gpr[5] = (unsigned long) &rt_sf->uc;
 885	regs->gpr[6] = (unsigned long) rt_sf;
 886	regs->nip = (unsigned long) ka->sa.sa_handler;
 887	/* enter the signal handler in big-endian mode */
 888	regs->msr &= ~MSR_LE;
 889	return 1;
 
 890
 891badframe:
 892#ifdef DEBUG_SIG
 893	printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n",
 894	       regs, frame, newsp);
 895#endif
 896	if (show_unhandled_signals)
 897		printk_ratelimited(KERN_INFO
 898				   "%s[%d]: bad frame in handle_rt_signal32: "
 899				   "%p nip %08lx lr %08lx\n",
 900				   current->comm, current->pid,
 901				   addr, regs->nip, regs->link);
 902
 903	force_sigsegv(sig, current);
 904	return 0;
 905}
 906
 907static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
 908{
 909	sigset_t set;
 910	struct mcontext __user *mcp;
 911
 912	if (get_sigset_t(&set, &ucp->uc_sigmask))
 913		return -EFAULT;
 914#ifdef CONFIG_PPC64
 915	{
 916		u32 cmcp;
 917
 918		if (__get_user(cmcp, &ucp->uc_regs))
 919			return -EFAULT;
 920		mcp = (struct mcontext __user *)(u64)cmcp;
 921		/* no need to check access_ok(mcp), since mcp < 4GB */
 922	}
 923#else
 924	if (__get_user(mcp, &ucp->uc_regs))
 925		return -EFAULT;
 926	if (!access_ok(VERIFY_READ, mcp, sizeof(*mcp)))
 927		return -EFAULT;
 928#endif
 929	restore_sigmask(&set);
 930	if (restore_user_regs(regs, mcp, sig))
 931		return -EFAULT;
 932
 933	return 0;
 934}
 935
 936long sys_swapcontext(struct ucontext __user *old_ctx,
 937		     struct ucontext __user *new_ctx,
 938		     int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 939{
 940	unsigned char tmp;
 941	int ctx_has_vsx_region = 0;
 942
 943#ifdef CONFIG_PPC64
 944	unsigned long new_msr = 0;
 945
 946	if (new_ctx) {
 947		struct mcontext __user *mcp;
 948		u32 cmcp;
 949
 950		/*
 951		 * Get pointer to the real mcontext.  No need for
 952		 * access_ok since we are dealing with compat
 953		 * pointers.
 954		 */
 955		if (__get_user(cmcp, &new_ctx->uc_regs))
 956			return -EFAULT;
 957		mcp = (struct mcontext __user *)(u64)cmcp;
 958		if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
 959			return -EFAULT;
 960	}
 961	/*
 962	 * Check that the context is not smaller than the original
 963	 * size (with VMX but without VSX)
 964	 */
 965	if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
 966		return -EINVAL;
 967	/*
 968	 * If the new context state sets the MSR VSX bits but
 969	 * it doesn't provide VSX state.
 970	 */
 971	if ((ctx_size < sizeof(struct ucontext)) &&
 972	    (new_msr & MSR_VSX))
 973		return -EINVAL;
 974	/* Does the context have enough room to store VSX data? */
 975	if (ctx_size >= sizeof(struct ucontext))
 976		ctx_has_vsx_region = 1;
 977#else
 978	/* Context size is for future use. Right now, we only make sure
 979	 * we are passed something we understand
 980	 */
 981	if (ctx_size < sizeof(struct ucontext))
 982		return -EINVAL;
 983#endif
 984	if (old_ctx != NULL) {
 985		struct mcontext __user *mctx;
 986
 987		/*
 988		 * old_ctx might not be 16-byte aligned, in which
 989		 * case old_ctx->uc_mcontext won't be either.
 990		 * Because we have the old_ctx->uc_pad2 field
 991		 * before old_ctx->uc_mcontext, we need to round down
 992		 * from &old_ctx->uc_mcontext to a 16-byte boundary.
 993		 */
 994		mctx = (struct mcontext __user *)
 995			((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
 996		if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size)
 997		    || save_user_regs(regs, mctx, 0, ctx_has_vsx_region)
 998		    || put_sigset_t(&old_ctx->uc_sigmask, &current->blocked)
 999		    || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
1000			return -EFAULT;
1001	}
1002	if (new_ctx == NULL)
1003		return 0;
1004	if (!access_ok(VERIFY_READ, new_ctx, ctx_size)
1005	    || __get_user(tmp, (u8 __user *) new_ctx)
1006	    || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
1007		return -EFAULT;
1008
1009	/*
1010	 * If we get a fault copying the context into the kernel's
1011	 * image of the user's registers, we can't just return -EFAULT
1012	 * because the user's registers will be corrupted.  For instance
1013	 * the NIP value may have been updated but not some of the
1014	 * other registers.  Given that we have done the access_ok
1015	 * and successfully read the first and last bytes of the region
1016	 * above, this should only happen in an out-of-memory situation
1017	 * or if another thread unmaps the region containing the context.
1018	 * We kill the task with a SIGSEGV in this situation.
1019	 */
1020	if (do_setcontext(new_ctx, regs, 0))
1021		do_exit(SIGSEGV);
1022
1023	set_thread_flag(TIF_RESTOREALL);
1024	return 0;
1025}
1026
1027long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1028		     struct pt_regs *regs)
 
 
 
1029{
1030	struct rt_sigframe __user *rt_sf;
1031
 
 
 
 
 
 
1032	/* Always make any pending restarted system calls return -EINTR */
1033	current_thread_info()->restart_block.fn = do_no_restart_syscall;
1034
1035	rt_sf = (struct rt_sigframe __user *)
1036		(regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1037	if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
1038		goto bad;
1039	if (do_setcontext(&rt_sf->uc, regs, 1))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1040		goto bad;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1041
1042	/*
1043	 * It's not clear whether or why it is desirable to save the
1044	 * sigaltstack setting on signal delivery and restore it on
1045	 * signal return.  But other architectures do this and we have
1046	 * always done it up until now so it is probably better not to
1047	 * change it.  -- paulus
1048	 */
1049#ifdef CONFIG_PPC64
1050	/*
1051	 * We use the compat_sys_ version that does the 32/64 bits conversion
1052	 * and takes userland pointer directly. What about error checking ?
1053	 * nobody does any...
1054	 */
1055	compat_sys_sigaltstack((u32)(u64)&rt_sf->uc.uc_stack, 0, 0, 0, 0, 0, regs);
1056#else
1057	do_sigaltstack(&rt_sf->uc.uc_stack, NULL, regs->gpr[1]);
 
1058#endif
1059	set_thread_flag(TIF_RESTOREALL);
1060	return 0;
1061
1062 bad:
1063	if (show_unhandled_signals)
1064		printk_ratelimited(KERN_INFO
1065				   "%s[%d]: bad frame in sys_rt_sigreturn: "
1066				   "%p nip %08lx lr %08lx\n",
1067				   current->comm, current->pid,
1068				   rt_sf, regs->nip, regs->link);
1069
1070	force_sig(SIGSEGV, current);
1071	return 0;
1072}
1073
1074#ifdef CONFIG_PPC32
1075int sys_debug_setcontext(struct ucontext __user *ctx,
1076			 int ndbg, struct sig_dbg_op __user *dbg,
1077			 int r6, int r7, int r8,
1078			 struct pt_regs *regs)
1079{
 
1080	struct sig_dbg_op op;
1081	int i;
1082	unsigned char tmp;
1083	unsigned long new_msr = regs->msr;
1084#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1085	unsigned long new_dbcr0 = current->thread.dbcr0;
1086#endif
1087
1088	for (i=0; i<ndbg; i++) {
1089		if (copy_from_user(&op, dbg + i, sizeof(op)))
1090			return -EFAULT;
1091		switch (op.dbg_type) {
1092		case SIG_DBG_SINGLE_STEPPING:
1093#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1094			if (op.dbg_value) {
1095				new_msr |= MSR_DE;
1096				new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1097			} else {
1098				new_dbcr0 &= ~DBCR0_IC;
1099				if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1100						current->thread.dbcr1)) {
1101					new_msr &= ~MSR_DE;
1102					new_dbcr0 &= ~DBCR0_IDM;
1103				}
1104			}
1105#else
1106			if (op.dbg_value)
1107				new_msr |= MSR_SE;
1108			else
1109				new_msr &= ~MSR_SE;
1110#endif
1111			break;
1112		case SIG_DBG_BRANCH_TRACING:
1113#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1114			return -EINVAL;
1115#else
1116			if (op.dbg_value)
1117				new_msr |= MSR_BE;
1118			else
1119				new_msr &= ~MSR_BE;
1120#endif
1121			break;
1122
1123		default:
1124			return -EINVAL;
1125		}
1126	}
1127
1128	/* We wait until here to actually install the values in the
1129	   registers so if we fail in the above loop, it will not
1130	   affect the contents of these registers.  After this point,
1131	   failure is a problem, anyway, and it's very unlikely unless
1132	   the user is really doing something wrong. */
1133	regs->msr = new_msr;
1134#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1135	current->thread.dbcr0 = new_dbcr0;
1136#endif
1137
1138	if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx))
1139	    || __get_user(tmp, (u8 __user *) ctx)
1140	    || __get_user(tmp, (u8 __user *) (ctx + 1) - 1))
1141		return -EFAULT;
1142
1143	/*
1144	 * If we get a fault copying the context into the kernel's
1145	 * image of the user's registers, we can't just return -EFAULT
1146	 * because the user's registers will be corrupted.  For instance
1147	 * the NIP value may have been updated but not some of the
1148	 * other registers.  Given that we have done the access_ok
1149	 * and successfully read the first and last bytes of the region
1150	 * above, this should only happen in an out-of-memory situation
1151	 * or if another thread unmaps the region containing the context.
1152	 * We kill the task with a SIGSEGV in this situation.
1153	 */
1154	if (do_setcontext(ctx, regs, 1)) {
1155		if (show_unhandled_signals)
1156			printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1157					   "sys_debug_setcontext: %p nip %08lx "
1158					   "lr %08lx\n",
1159					   current->comm, current->pid,
1160					   ctx, regs->nip, regs->link);
1161
1162		force_sig(SIGSEGV, current);
1163		goto out;
1164	}
1165
1166	/*
1167	 * It's not clear whether or why it is desirable to save the
1168	 * sigaltstack setting on signal delivery and restore it on
1169	 * signal return.  But other architectures do this and we have
1170	 * always done it up until now so it is probably better not to
1171	 * change it.  -- paulus
1172	 */
1173	do_sigaltstack(&ctx->uc_stack, NULL, regs->gpr[1]);
1174
1175	set_thread_flag(TIF_RESTOREALL);
1176 out:
1177	return 0;
1178}
1179#endif
1180
1181/*
1182 * OK, we're invoking a handler
1183 */
1184int handle_signal32(unsigned long sig, struct k_sigaction *ka,
1185		    siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
1186{
1187	struct sigcontext __user *sc;
1188	struct sigframe __user *frame;
 
1189	unsigned long newsp = 0;
 
 
 
 
 
 
 
 
 
1190
1191	/* Set up Signal Frame */
1192	frame = get_sigframe(ka, regs, sizeof(*frame), 1);
1193	if (unlikely(frame == NULL))
1194		goto badframe;
1195	sc = (struct sigcontext __user *) &frame->sctx;
1196
1197#if _NSIG != 64
1198#error "Please adjust handle_signal()"
1199#endif
1200	if (__put_user(to_user_ptr(ka->sa.sa_handler), &sc->handler)
1201	    || __put_user(oldset->sig[0], &sc->oldmask)
1202#ifdef CONFIG_PPC64
1203	    || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1204#else
1205	    || __put_user(oldset->sig[1], &sc->_unused[3])
1206#endif
1207	    || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1208	    || __put_user(sig, &sc->signal))
1209		goto badframe;
1210
1211	if (vdso32_sigtramp && current->mm->context.vdso_base) {
1212		if (save_user_regs(regs, &frame->mctx, 0, 1))
 
 
 
 
 
 
 
 
 
 
 
1213			goto badframe;
1214		regs->link = current->mm->context.vdso_base + vdso32_sigtramp;
1215	} else {
1216		if (save_user_regs(regs, &frame->mctx, __NR_sigreturn, 1))
 
 
1217			goto badframe;
1218		regs->link = (unsigned long) frame->mctx.tramp;
1219	}
1220
1221	current->thread.fpscr.val = 0;	/* turn off all fp exceptions */
 
 
1222
1223	/* create a stack frame for the caller of the handler */
1224	newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1225	if (put_user(regs->gpr[1], (u32 __user *)newsp))
1226		goto badframe;
1227
1228	regs->gpr[1] = newsp;
1229	regs->gpr[3] = sig;
1230	regs->gpr[4] = (unsigned long) sc;
1231	regs->nip = (unsigned long) ka->sa.sa_handler;
1232	/* enter the signal handler in big-endian mode */
1233	regs->msr &= ~MSR_LE;
1234
1235	return 1;
1236
1237badframe:
1238#ifdef DEBUG_SIG
1239	printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n",
1240	       regs, frame, newsp);
1241#endif
1242	if (show_unhandled_signals)
1243		printk_ratelimited(KERN_INFO
1244				   "%s[%d]: bad frame in handle_signal32: "
1245				   "%p nip %08lx lr %08lx\n",
1246				   current->comm, current->pid,
1247				   frame, regs->nip, regs->link);
1248
1249	force_sigsegv(sig, current);
1250	return 0;
1251}
1252
1253/*
1254 * Do a signal return; undo the signal stack.
1255 */
1256long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1257		       struct pt_regs *regs)
 
 
 
1258{
 
 
1259	struct sigcontext __user *sc;
1260	struct sigcontext sigctx;
1261	struct mcontext __user *sr;
1262	void __user *addr;
1263	sigset_t set;
 
 
 
 
1264
1265	/* Always make any pending restarted system calls return -EINTR */
1266	current_thread_info()->restart_block.fn = do_no_restart_syscall;
1267
1268	sc = (struct sigcontext __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
 
1269	addr = sc;
1270	if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1271		goto badframe;
1272
1273#ifdef CONFIG_PPC64
1274	/*
1275	 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1276	 * unused part of the signal stackframe
1277	 */
1278	set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1279#else
1280	set.sig[0] = sigctx.oldmask;
1281	set.sig[1] = sigctx._unused[3];
1282#endif
1283	restore_sigmask(&set);
1284
1285	sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1286	addr = sr;
1287	if (!access_ok(VERIFY_READ, sr, sizeof(*sr))
1288	    || restore_user_regs(regs, sr, 1))
1289		goto badframe;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1290
1291	set_thread_flag(TIF_RESTOREALL);
1292	return 0;
1293
1294badframe:
1295	if (show_unhandled_signals)
1296		printk_ratelimited(KERN_INFO
1297				   "%s[%d]: bad frame in sys_sigreturn: "
1298				   "%p nip %08lx lr %08lx\n",
1299				   current->comm, current->pid,
1300				   addr, regs->nip, regs->link);
1301
1302	force_sig(SIGSEGV, current);
1303	return 0;
1304}