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authorroot <root@artemis.panaceas.org>2015-12-25 04:40:36 +0000
committerroot <root@artemis.panaceas.org>2015-12-25 04:40:36 +0000
commit849369d6c66d3054688672f97d31fceb8e8230fb (patch)
tree6135abc790ca67dedbe07c39806591e70eda81ce /arch/powerpc/kernel/signal_32.c
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initial_commit
Diffstat (limited to 'arch/powerpc/kernel/signal_32.c')
-rw-r--r--arch/powerpc/kernel/signal_32.c1304
1 files changed, 1304 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
new file mode 100644
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--- /dev/null
+++ b/arch/powerpc/kernel/signal_32.c
@@ -0,0 +1,1304 @@
+/*
+ * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
+ *
+ * PowerPC version
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ * Copyright (C) 2001 IBM
+ * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ *
+ * Derived from "arch/i386/kernel/signal.c"
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/elf.h>
+#include <linux/ptrace.h>
+#include <linux/ratelimit.h>
+#ifdef CONFIG_PPC64
+#include <linux/syscalls.h>
+#include <linux/compat.h>
+#else
+#include <linux/wait.h>
+#include <linux/unistd.h>
+#include <linux/stddef.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/freezer.h>
+#endif
+
+#include <asm/uaccess.h>
+#include <asm/cacheflush.h>
+#include <asm/syscalls.h>
+#include <asm/sigcontext.h>
+#include <asm/vdso.h>
+#ifdef CONFIG_PPC64
+#include "ppc32.h"
+#include <asm/unistd.h>
+#else
+#include <asm/ucontext.h>
+#include <asm/pgtable.h>
+#endif
+
+#include "signal.h"
+
+#undef DEBUG_SIG
+
+#ifdef CONFIG_PPC64
+#define sys_sigsuspend compat_sys_sigsuspend
+#define sys_rt_sigsuspend compat_sys_rt_sigsuspend
+#define sys_rt_sigreturn compat_sys_rt_sigreturn
+#define sys_sigaction compat_sys_sigaction
+#define sys_swapcontext compat_sys_swapcontext
+#define sys_sigreturn compat_sys_sigreturn
+
+#define old_sigaction old_sigaction32
+#define sigcontext sigcontext32
+#define mcontext mcontext32
+#define ucontext ucontext32
+
+/*
+ * Userspace code may pass a ucontext which doesn't include VSX added
+ * at the end. We need to check for this case.
+ */
+#define UCONTEXTSIZEWITHOUTVSX \
+ (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
+
+/*
+ * Returning 0 means we return to userspace via
+ * ret_from_except and thus restore all user
+ * registers from *regs. This is what we need
+ * to do when a signal has been delivered.
+ */
+
+#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
+#undef __SIGNAL_FRAMESIZE
+#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
+#undef ELF_NVRREG
+#define ELF_NVRREG ELF_NVRREG32
+
+/*
+ * Functions for flipping sigsets (thanks to brain dead generic
+ * implementation that makes things simple for little endian only)
+ */
+static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
+{
+ compat_sigset_t cset;
+
+ switch (_NSIG_WORDS) {
+ case 4: cset.sig[5] = set->sig[3] & 0xffffffffull;
+ cset.sig[7] = set->sig[3] >> 32;
+ case 3: cset.sig[4] = set->sig[2] & 0xffffffffull;
+ cset.sig[5] = set->sig[2] >> 32;
+ case 2: cset.sig[2] = set->sig[1] & 0xffffffffull;
+ cset.sig[3] = set->sig[1] >> 32;
+ case 1: cset.sig[0] = set->sig[0] & 0xffffffffull;
+ cset.sig[1] = set->sig[0] >> 32;
+ }
+ return copy_to_user(uset, &cset, sizeof(*uset));
+}
+
+static inline int get_sigset_t(sigset_t *set,
+ const compat_sigset_t __user *uset)
+{
+ compat_sigset_t s32;
+
+ if (copy_from_user(&s32, uset, sizeof(*uset)))
+ return -EFAULT;
+
+ /*
+ * Swap the 2 words of the 64-bit sigset_t (they are stored
+ * in the "wrong" endian in 32-bit user storage).
+ */
+ switch (_NSIG_WORDS) {
+ case 4: set->sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
+ case 3: set->sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
+ case 2: set->sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
+ case 1: set->sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
+ }
+ return 0;
+}
+
+static inline int get_old_sigaction(struct k_sigaction *new_ka,
+ struct old_sigaction __user *act)
+{
+ compat_old_sigset_t mask;
+ compat_uptr_t handler, restorer;
+
+ if (get_user(handler, &act->sa_handler) ||
+ __get_user(restorer, &act->sa_restorer) ||
+ __get_user(new_ka->sa.sa_flags, &act->sa_flags) ||
+ __get_user(mask, &act->sa_mask))
+ return -EFAULT;
+ new_ka->sa.sa_handler = compat_ptr(handler);
+ new_ka->sa.sa_restorer = compat_ptr(restorer);
+ siginitset(&new_ka->sa.sa_mask, mask);
+ return 0;
+}
+
+#define to_user_ptr(p) ptr_to_compat(p)
+#define from_user_ptr(p) compat_ptr(p)
+
+static inline int save_general_regs(struct pt_regs *regs,
+ struct mcontext __user *frame)
+{
+ elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
+ int i;
+
+ WARN_ON(!FULL_REGS(regs));
+
+ for (i = 0; i <= PT_RESULT; i ++) {
+ if (i == 14 && !FULL_REGS(regs))
+ i = 32;
+ if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
+ return -EFAULT;
+ }
+ return 0;
+}
+
+static inline int restore_general_regs(struct pt_regs *regs,
+ struct mcontext __user *sr)
+{
+ elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
+ int i;
+
+ for (i = 0; i <= PT_RESULT; i++) {
+ if ((i == PT_MSR) || (i == PT_SOFTE))
+ continue;
+ if (__get_user(gregs[i], &sr->mc_gregs[i]))
+ return -EFAULT;
+ }
+ return 0;
+}
+
+#else /* CONFIG_PPC64 */
+
+#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
+
+static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
+{
+ return copy_to_user(uset, set, sizeof(*uset));
+}
+
+static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
+{
+ return copy_from_user(set, uset, sizeof(*uset));
+}
+
+static inline int get_old_sigaction(struct k_sigaction *new_ka,
+ struct old_sigaction __user *act)
+{
+ old_sigset_t mask;
+
+ if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+ __get_user(new_ka->sa.sa_handler, &act->sa_handler) ||
+ __get_user(new_ka->sa.sa_restorer, &act->sa_restorer))
+ return -EFAULT;
+ __get_user(new_ka->sa.sa_flags, &act->sa_flags);
+ __get_user(mask, &act->sa_mask);
+ siginitset(&new_ka->sa.sa_mask, mask);
+ return 0;
+}
+
+#define to_user_ptr(p) ((unsigned long)(p))
+#define from_user_ptr(p) ((void __user *)(p))
+
+static inline int save_general_regs(struct pt_regs *regs,
+ struct mcontext __user *frame)
+{
+ WARN_ON(!FULL_REGS(regs));
+ return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
+}
+
+static inline int restore_general_regs(struct pt_regs *regs,
+ struct mcontext __user *sr)
+{
+ /* copy up to but not including MSR */
+ if (__copy_from_user(regs, &sr->mc_gregs,
+ PT_MSR * sizeof(elf_greg_t)))
+ return -EFAULT;
+ /* copy from orig_r3 (the word after the MSR) up to the end */
+ if (__copy_from_user(&regs->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
+ GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
+ return -EFAULT;
+ return 0;
+}
+
+#endif /* CONFIG_PPC64 */
+
+/*
+ * Atomically swap in the new signal mask, and wait for a signal.
+ */
+long sys_sigsuspend(old_sigset_t mask)
+{
+ mask &= _BLOCKABLE;
+ spin_lock_irq(&current->sighand->siglock);
+ current->saved_sigmask = current->blocked;
+ siginitset(&current->blocked, mask);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ set_restore_sigmask();
+ return -ERESTARTNOHAND;
+}
+
+long sys_sigaction(int sig, struct old_sigaction __user *act,
+ struct old_sigaction __user *oact)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+
+#ifdef CONFIG_PPC64
+ if (sig < 0)
+ sig = -sig;
+#endif
+
+ if (act) {
+ if (get_old_sigaction(&new_ka, act))
+ return -EFAULT;
+ }
+
+ ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+ if (!ret && oact) {
+ if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+ __put_user(to_user_ptr(old_ka.sa.sa_handler),
+ &oact->sa_handler) ||
+ __put_user(to_user_ptr(old_ka.sa.sa_restorer),
+ &oact->sa_restorer) ||
+ __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
+ __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
+ return -EFAULT;
+ }
+
+ return ret;
+}
+
+/*
+ * When we have signals to deliver, we set up on the
+ * user stack, going down from the original stack pointer:
+ * an ABI gap of 56 words
+ * an mcontext struct
+ * a sigcontext struct
+ * a gap of __SIGNAL_FRAMESIZE bytes
+ *
+ * Each of these things must be a multiple of 16 bytes in size. The following
+ * structure represent all of this except the __SIGNAL_FRAMESIZE gap
+ *
+ */
+struct sigframe {
+ struct sigcontext sctx; /* the sigcontext */
+ struct mcontext mctx; /* all the register values */
+ /*
+ * Programs using the rs6000/xcoff abi can save up to 19 gp
+ * regs and 18 fp regs below sp before decrementing it.
+ */
+ int abigap[56];
+};
+
+/* We use the mc_pad field for the signal return trampoline. */
+#define tramp mc_pad
+
+/*
+ * When we have rt signals to deliver, we set up on the
+ * user stack, going down from the original stack pointer:
+ * one rt_sigframe struct (siginfo + ucontext + ABI gap)
+ * a gap of __SIGNAL_FRAMESIZE+16 bytes
+ * (the +16 is to get the siginfo and ucontext in the same
+ * positions as in older kernels).
+ *
+ * Each of these things must be a multiple of 16 bytes in size.
+ *
+ */
+struct rt_sigframe {
+#ifdef CONFIG_PPC64
+ compat_siginfo_t info;
+#else
+ struct siginfo info;
+#endif
+ struct ucontext uc;
+ /*
+ * Programs using the rs6000/xcoff abi can save up to 19 gp
+ * regs and 18 fp regs below sp before decrementing it.
+ */
+ int abigap[56];
+};
+
+#ifdef CONFIG_VSX
+unsigned long copy_fpr_to_user(void __user *to,
+ struct task_struct *task)
+{
+ double buf[ELF_NFPREG];
+ int i;
+
+ /* save FPR copy to local buffer then write to the thread_struct */
+ for (i = 0; i < (ELF_NFPREG - 1) ; i++)
+ buf[i] = task->thread.TS_FPR(i);
+ memcpy(&buf[i], &task->thread.fpscr, sizeof(double));
+ return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
+}
+
+unsigned long copy_fpr_from_user(struct task_struct *task,
+ void __user *from)
+{
+ double buf[ELF_NFPREG];
+ int i;
+
+ if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
+ return 1;
+ for (i = 0; i < (ELF_NFPREG - 1) ; i++)
+ task->thread.TS_FPR(i) = buf[i];
+ memcpy(&task->thread.fpscr, &buf[i], sizeof(double));
+
+ return 0;
+}
+
+unsigned long copy_vsx_to_user(void __user *to,
+ struct task_struct *task)
+{
+ double buf[ELF_NVSRHALFREG];
+ int i;
+
+ /* save FPR copy to local buffer then write to the thread_struct */
+ for (i = 0; i < ELF_NVSRHALFREG; i++)
+ buf[i] = task->thread.fpr[i][TS_VSRLOWOFFSET];
+ return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
+}
+
+unsigned long copy_vsx_from_user(struct task_struct *task,
+ void __user *from)
+{
+ double buf[ELF_NVSRHALFREG];
+ int i;
+
+ if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
+ return 1;
+ for (i = 0; i < ELF_NVSRHALFREG ; i++)
+ task->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];
+ return 0;
+}
+#else
+inline unsigned long copy_fpr_to_user(void __user *to,
+ struct task_struct *task)
+{
+ return __copy_to_user(to, task->thread.fpr,
+ ELF_NFPREG * sizeof(double));
+}
+
+inline unsigned long copy_fpr_from_user(struct task_struct *task,
+ void __user *from)
+{
+ return __copy_from_user(task->thread.fpr, from,
+ ELF_NFPREG * sizeof(double));
+}
+#endif
+
+/*
+ * Save the current user registers on the user stack.
+ * We only save the altivec/spe registers if the process has used
+ * altivec/spe instructions at some point.
+ */
+static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
+ int sigret, int ctx_has_vsx_region)
+{
+ unsigned long msr = regs->msr;
+
+ /* Make sure floating point registers are stored in regs */
+ flush_fp_to_thread(current);
+
+ /* save general registers */
+ if (save_general_regs(regs, frame))
+ return 1;
+
+#ifdef CONFIG_ALTIVEC
+ /* save altivec registers */
+ if (current->thread.used_vr) {
+ flush_altivec_to_thread(current);
+ if (__copy_to_user(&frame->mc_vregs, current->thread.vr,
+ ELF_NVRREG * sizeof(vector128)))
+ return 1;
+ /* set MSR_VEC in the saved MSR value to indicate that
+ frame->mc_vregs contains valid data */
+ msr |= MSR_VEC;
+ }
+ /* else assert((regs->msr & MSR_VEC) == 0) */
+
+ /* We always copy to/from vrsave, it's 0 if we don't have or don't
+ * use altivec. Since VSCR only contains 32 bits saved in the least
+ * significant bits of a vector, we "cheat" and stuff VRSAVE in the
+ * most significant bits of that same vector. --BenH
+ */
+ if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
+ return 1;
+#endif /* CONFIG_ALTIVEC */
+ if (copy_fpr_to_user(&frame->mc_fregs, current))
+ return 1;
+#ifdef CONFIG_VSX
+ /*
+ * Copy VSR 0-31 upper half from thread_struct to local
+ * buffer, then write that to userspace. Also set MSR_VSX in
+ * the saved MSR value to indicate that frame->mc_vregs
+ * contains valid data
+ */
+ if (current->thread.used_vsr && ctx_has_vsx_region) {
+ __giveup_vsx(current);
+ if (copy_vsx_to_user(&frame->mc_vsregs, current))
+ return 1;
+ msr |= MSR_VSX;
+ }
+#endif /* CONFIG_VSX */
+#ifdef CONFIG_SPE
+ /* save spe registers */
+ if (current->thread.used_spe) {
+ flush_spe_to_thread(current);
+ if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
+ ELF_NEVRREG * sizeof(u32)))
+ return 1;
+ /* set MSR_SPE in the saved MSR value to indicate that
+ frame->mc_vregs contains valid data */
+ msr |= MSR_SPE;
+ }
+ /* else assert((regs->msr & MSR_SPE) == 0) */
+
+ /* We always copy to/from spefscr */
+ if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
+ return 1;
+#endif /* CONFIG_SPE */
+
+ if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
+ return 1;
+ if (sigret) {
+ /* Set up the sigreturn trampoline: li r0,sigret; sc */
+ if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
+ || __put_user(0x44000002UL, &frame->tramp[1]))
+ return 1;
+ flush_icache_range((unsigned long) &frame->tramp[0],
+ (unsigned long) &frame->tramp[2]);
+ }
+
+ return 0;
+}
+
+/*
+ * Restore the current user register values from the user stack,
+ * (except for MSR).
+ */
+static long restore_user_regs(struct pt_regs *regs,
+ struct mcontext __user *sr, int sig)
+{
+ long err;
+ unsigned int save_r2 = 0;
+ unsigned long msr;
+#ifdef CONFIG_VSX
+ int i;
+#endif
+
+ /*
+ * restore general registers but not including MSR or SOFTE. Also
+ * take care of keeping r2 (TLS) intact if not a signal
+ */
+ if (!sig)
+ save_r2 = (unsigned int)regs->gpr[2];
+ err = restore_general_regs(regs, sr);
+ regs->trap = 0;
+ err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
+ if (!sig)
+ regs->gpr[2] = (unsigned long) save_r2;
+ if (err)
+ return 1;
+
+ /* if doing signal return, restore the previous little-endian mode */
+ if (sig)
+ regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
+
+ /*
+ * Do this before updating the thread state in
+ * current->thread.fpr/vr/evr. That way, if we get preempted
+ * and another task grabs the FPU/Altivec/SPE, it won't be
+ * tempted to save the current CPU state into the thread_struct
+ * and corrupt what we are writing there.
+ */
+ discard_lazy_cpu_state();
+
+#ifdef CONFIG_ALTIVEC
+ /*
+ * Force the process to reload the altivec registers from
+ * current->thread when it next does altivec instructions
+ */
+ regs->msr &= ~MSR_VEC;
+ if (msr & MSR_VEC) {
+ /* restore altivec registers from the stack */
+ if (__copy_from_user(current->thread.vr, &sr->mc_vregs,
+ sizeof(sr->mc_vregs)))
+ return 1;
+ } else if (current->thread.used_vr)
+ memset(current->thread.vr, 0, ELF_NVRREG * sizeof(vector128));
+
+ /* Always get VRSAVE back */
+ if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
+ return 1;
+#endif /* CONFIG_ALTIVEC */
+ if (copy_fpr_from_user(current, &sr->mc_fregs))
+ return 1;
+
+#ifdef CONFIG_VSX
+ /*
+ * Force the process to reload the VSX registers from
+ * current->thread when it next does VSX instruction.
+ */
+ regs->msr &= ~MSR_VSX;
+ if (msr & MSR_VSX) {
+ /*
+ * Restore altivec registers from the stack to a local
+ * buffer, then write this out to the thread_struct
+ */
+ if (copy_vsx_from_user(current, &sr->mc_vsregs))
+ return 1;
+ } else if (current->thread.used_vsr)
+ for (i = 0; i < 32 ; i++)
+ current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;
+#endif /* CONFIG_VSX */
+ /*
+ * force the process to reload the FP registers from
+ * current->thread when it next does FP instructions
+ */
+ regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
+
+#ifdef CONFIG_SPE
+ /* force the process to reload the spe registers from
+ current->thread when it next does spe instructions */
+ regs->msr &= ~MSR_SPE;
+ if (msr & MSR_SPE) {
+ /* restore spe registers from the stack */
+ if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
+ ELF_NEVRREG * sizeof(u32)))
+ return 1;
+ } else if (current->thread.used_spe)
+ memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
+
+ /* Always get SPEFSCR back */
+ if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
+ return 1;
+#endif /* CONFIG_SPE */
+
+ return 0;
+}
+
+#ifdef CONFIG_PPC64
+long compat_sys_rt_sigaction(int sig, const struct sigaction32 __user *act,
+ struct sigaction32 __user *oact, size_t sigsetsize)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+
+ /* XXX: Don't preclude handling different sized sigset_t's. */
+ if (sigsetsize != sizeof(compat_sigset_t))
+ return -EINVAL;
+
+ if (act) {
+ compat_uptr_t handler;
+
+ ret = get_user(handler, &act->sa_handler);
+ new_ka.sa.sa_handler = compat_ptr(handler);
+ ret |= get_sigset_t(&new_ka.sa.sa_mask, &act->sa_mask);
+ ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
+ if (ret)
+ return -EFAULT;
+ }
+
+ ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+ if (!ret && oact) {
+ ret = put_user(to_user_ptr(old_ka.sa.sa_handler), &oact->sa_handler);
+ ret |= put_sigset_t(&oact->sa_mask, &old_ka.sa.sa_mask);
+ ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
+ }
+ return ret;
+}
+
+/*
+ * Note: it is necessary to treat how as an unsigned int, with the
+ * corresponding cast to a signed int to insure that the proper
+ * conversion (sign extension) between the register representation
+ * of a signed int (msr in 32-bit mode) and the register representation
+ * of a signed int (msr in 64-bit mode) is performed.
+ */
+long compat_sys_rt_sigprocmask(u32 how, compat_sigset_t __user *set,
+ compat_sigset_t __user *oset, size_t sigsetsize)
+{
+ sigset_t s;
+ sigset_t __user *up;
+ int ret;
+ mm_segment_t old_fs = get_fs();
+
+ if (set) {
+ if (get_sigset_t(&s, set))
+ return -EFAULT;
+ }
+
+ set_fs(KERNEL_DS);
+ /* This is valid because of the set_fs() */
+ up = (sigset_t __user *) &s;
+ ret = sys_rt_sigprocmask((int)how, set ? up : NULL, oset ? up : NULL,
+ sigsetsize);
+ set_fs(old_fs);
+ if (ret)
+ return ret;
+ if (oset) {
+ if (put_sigset_t(oset, &s))
+ return -EFAULT;
+ }
+ return 0;
+}
+
+long compat_sys_rt_sigpending(compat_sigset_t __user *set, compat_size_t sigsetsize)
+{
+ sigset_t s;
+ int ret;
+ mm_segment_t old_fs = get_fs();
+
+ set_fs(KERNEL_DS);
+ /* The __user pointer cast is valid because of the set_fs() */
+ ret = sys_rt_sigpending((sigset_t __user *) &s, sigsetsize);
+ set_fs(old_fs);
+ if (!ret) {
+ if (put_sigset_t(set, &s))
+ return -EFAULT;
+ }
+ return ret;
+}
+
+
+int copy_siginfo_to_user32(struct compat_siginfo __user *d, siginfo_t *s)
+{
+ int err;
+
+ if (!access_ok (VERIFY_WRITE, d, sizeof(*d)))
+ return -EFAULT;
+
+ /* If you change siginfo_t structure, please be sure
+ * this code is fixed accordingly.
+ * It should never copy any pad contained in the structure
+ * to avoid security leaks, but must copy the generic
+ * 3 ints plus the relevant union member.
+ * This routine must convert siginfo from 64bit to 32bit as well
+ * at the same time.
+ */
+ err = __put_user(s->si_signo, &d->si_signo);
+ err |= __put_user(s->si_errno, &d->si_errno);
+ err |= __put_user((short)s->si_code, &d->si_code);
+ if (s->si_code < 0)
+ err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad,
+ SI_PAD_SIZE32);
+ else switch(s->si_code >> 16) {
+ case __SI_CHLD >> 16:
+ err |= __put_user(s->si_pid, &d->si_pid);
+ err |= __put_user(s->si_uid, &d->si_uid);
+ err |= __put_user(s->si_utime, &d->si_utime);
+ err |= __put_user(s->si_stime, &d->si_stime);
+ err |= __put_user(s->si_status, &d->si_status);
+ break;
+ case __SI_FAULT >> 16:
+ err |= __put_user((unsigned int)(unsigned long)s->si_addr,
+ &d->si_addr);
+ break;
+ case __SI_POLL >> 16:
+ err |= __put_user(s->si_band, &d->si_band);
+ err |= __put_user(s->si_fd, &d->si_fd);
+ break;
+ case __SI_TIMER >> 16:
+ err |= __put_user(s->si_tid, &d->si_tid);
+ err |= __put_user(s->si_overrun, &d->si_overrun);
+ err |= __put_user(s->si_int, &d->si_int);
+ break;
+ case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
+ case __SI_MESGQ >> 16:
+ err |= __put_user(s->si_int, &d->si_int);
+ /* fallthrough */
+ case __SI_KILL >> 16:
+ default:
+ err |= __put_user(s->si_pid, &d->si_pid);
+ err |= __put_user(s->si_uid, &d->si_uid);
+ break;
+ }
+ return err;
+}
+
+#define copy_siginfo_to_user copy_siginfo_to_user32
+
+int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from)
+{
+ memset(to, 0, sizeof *to);
+
+ if (copy_from_user(to, from, 3*sizeof(int)) ||
+ copy_from_user(to->_sifields._pad,
+ from->_sifields._pad, SI_PAD_SIZE32))
+ return -EFAULT;
+
+ return 0;
+}
+
+/*
+ * Note: it is necessary to treat pid and sig as unsigned ints, with the
+ * corresponding cast to a signed int to insure that the proper conversion
+ * (sign extension) between the register representation of a signed int
+ * (msr in 32-bit mode) and the register representation of a signed int
+ * (msr in 64-bit mode) is performed.
+ */
+long compat_sys_rt_sigqueueinfo(u32 pid, u32 sig, compat_siginfo_t __user *uinfo)
+{
+ siginfo_t info;
+ int ret;
+ mm_segment_t old_fs = get_fs();
+
+ ret = copy_siginfo_from_user32(&info, uinfo);
+ if (unlikely(ret))
+ return ret;
+
+ set_fs (KERNEL_DS);
+ /* The __user pointer cast is valid becasuse of the set_fs() */
+ ret = sys_rt_sigqueueinfo((int)pid, (int)sig, (siginfo_t __user *) &info);
+ set_fs (old_fs);
+ return ret;
+}
+/*
+ * Start Alternate signal stack support
+ *
+ * System Calls
+ * sigaltatck compat_sys_sigaltstack
+ */
+
+int compat_sys_sigaltstack(u32 __new, u32 __old, int r5,
+ int r6, int r7, int r8, struct pt_regs *regs)
+{
+ stack_32_t __user * newstack = compat_ptr(__new);
+ stack_32_t __user * oldstack = compat_ptr(__old);
+ stack_t uss, uoss;
+ int ret;
+ mm_segment_t old_fs;
+ unsigned long sp;
+ compat_uptr_t ss_sp;
+
+ /*
+ * set sp to the user stack on entry to the system call
+ * the system call router sets R9 to the saved registers
+ */
+ sp = regs->gpr[1];
+
+ /* Put new stack info in local 64 bit stack struct */
+ if (newstack) {
+ if (get_user(ss_sp, &newstack->ss_sp) ||
+ __get_user(uss.ss_flags, &newstack->ss_flags) ||
+ __get_user(uss.ss_size, &newstack->ss_size))
+ return -EFAULT;
+ uss.ss_sp = compat_ptr(ss_sp);
+ }
+
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ /* The __user pointer casts are valid because of the set_fs() */
+ ret = do_sigaltstack(
+ newstack ? (stack_t __user *) &uss : NULL,
+ oldstack ? (stack_t __user *) &uoss : NULL,
+ sp);
+ set_fs(old_fs);
+ /* Copy the stack information to the user output buffer */
+ if (!ret && oldstack &&
+ (put_user(ptr_to_compat(uoss.ss_sp), &oldstack->ss_sp) ||
+ __put_user(uoss.ss_flags, &oldstack->ss_flags) ||
+ __put_user(uoss.ss_size, &oldstack->ss_size)))
+ return -EFAULT;
+ return ret;
+}
+#endif /* CONFIG_PPC64 */
+
+/*
+ * Set up a signal frame for a "real-time" signal handler
+ * (one which gets siginfo).
+ */
+int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
+ siginfo_t *info, sigset_t *oldset,
+ struct pt_regs *regs)
+{
+ struct rt_sigframe __user *rt_sf;
+ struct mcontext __user *frame;
+ void __user *addr;
+ unsigned long newsp = 0;
+
+ /* Set up Signal Frame */
+ /* Put a Real Time Context onto stack */
+ rt_sf = get_sigframe(ka, regs, sizeof(*rt_sf), 1);
+ addr = rt_sf;
+ if (unlikely(rt_sf == NULL))
+ goto badframe;
+
+ /* Put the siginfo & fill in most of the ucontext */
+ if (copy_siginfo_to_user(&rt_sf->info, info)
+ || __put_user(0, &rt_sf->uc.uc_flags)
+ || __put_user(0, &rt_sf->uc.uc_link)
+ || __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)
+ || __put_user(sas_ss_flags(regs->gpr[1]),
+ &rt_sf->uc.uc_stack.ss_flags)
+ || __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size)
+ || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
+ &rt_sf->uc.uc_regs)
+ || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
+ goto badframe;
+
+ /* Save user registers on the stack */
+ frame = &rt_sf->uc.uc_mcontext;
+ addr = frame;
+ if (vdso32_rt_sigtramp && current->mm->context.vdso_base) {
+ if (save_user_regs(regs, frame, 0, 1))
+ goto badframe;
+ regs->link = current->mm->context.vdso_base + vdso32_rt_sigtramp;
+ } else {
+ if (save_user_regs(regs, frame, __NR_rt_sigreturn, 1))
+ goto badframe;
+ regs->link = (unsigned long) frame->tramp;
+ }
+
+ current->thread.fpscr.val = 0; /* turn off all fp exceptions */
+
+ /* create a stack frame for the caller of the handler */
+ newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
+ addr = (void __user *)regs->gpr[1];
+ if (put_user(regs->gpr[1], (u32 __user *)newsp))
+ goto badframe;
+
+ /* Fill registers for signal handler */
+ regs->gpr[1] = newsp;
+ regs->gpr[3] = sig;
+ regs->gpr[4] = (unsigned long) &rt_sf->info;
+ regs->gpr[5] = (unsigned long) &rt_sf->uc;
+ regs->gpr[6] = (unsigned long) rt_sf;
+ regs->nip = (unsigned long) ka->sa.sa_handler;
+ /* enter the signal handler in big-endian mode */
+ regs->msr &= ~MSR_LE;
+ return 1;
+
+badframe:
+#ifdef DEBUG_SIG
+ printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n",
+ regs, frame, newsp);
+#endif
+ if (show_unhandled_signals)
+ printk_ratelimited(KERN_INFO
+ "%s[%d]: bad frame in handle_rt_signal32: "
+ "%p nip %08lx lr %08lx\n",
+ current->comm, current->pid,
+ addr, regs->nip, regs->link);
+
+ force_sigsegv(sig, current);
+ return 0;
+}
+
+static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
+{
+ sigset_t set;
+ struct mcontext __user *mcp;
+
+ if (get_sigset_t(&set, &ucp->uc_sigmask))
+ return -EFAULT;
+#ifdef CONFIG_PPC64
+ {
+ u32 cmcp;
+
+ if (__get_user(cmcp, &ucp->uc_regs))
+ return -EFAULT;
+ mcp = (struct mcontext __user *)(u64)cmcp;
+ /* no need to check access_ok(mcp), since mcp < 4GB */
+ }
+#else
+ if (__get_user(mcp, &ucp->uc_regs))
+ return -EFAULT;
+ if (!access_ok(VERIFY_READ, mcp, sizeof(*mcp)))
+ return -EFAULT;
+#endif
+ restore_sigmask(&set);
+ if (restore_user_regs(regs, mcp, sig))
+ return -EFAULT;
+
+ return 0;
+}
+
+long sys_swapcontext(struct ucontext __user *old_ctx,
+ struct ucontext __user *new_ctx,
+ int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
+{
+ unsigned char tmp;
+ int ctx_has_vsx_region = 0;
+
+#ifdef CONFIG_PPC64
+ unsigned long new_msr = 0;
+
+ if (new_ctx) {
+ struct mcontext __user *mcp;
+ u32 cmcp;
+
+ /*
+ * Get pointer to the real mcontext. No need for
+ * access_ok since we are dealing with compat
+ * pointers.
+ */
+ if (__get_user(cmcp, &new_ctx->uc_regs))
+ return -EFAULT;
+ mcp = (struct mcontext __user *)(u64)cmcp;
+ if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
+ return -EFAULT;
+ }
+ /*
+ * Check that the context is not smaller than the original
+ * size (with VMX but without VSX)
+ */
+ if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
+ return -EINVAL;
+ /*
+ * If the new context state sets the MSR VSX bits but
+ * it doesn't provide VSX state.
+ */
+ if ((ctx_size < sizeof(struct ucontext)) &&
+ (new_msr & MSR_VSX))
+ return -EINVAL;
+ /* Does the context have enough room to store VSX data? */
+ if (ctx_size >= sizeof(struct ucontext))
+ ctx_has_vsx_region = 1;
+#else
+ /* Context size is for future use. Right now, we only make sure
+ * we are passed something we understand
+ */
+ if (ctx_size < sizeof(struct ucontext))
+ return -EINVAL;
+#endif
+ if (old_ctx != NULL) {
+ struct mcontext __user *mctx;
+
+ /*
+ * old_ctx might not be 16-byte aligned, in which
+ * case old_ctx->uc_mcontext won't be either.
+ * Because we have the old_ctx->uc_pad2 field
+ * before old_ctx->uc_mcontext, we need to round down
+ * from &old_ctx->uc_mcontext to a 16-byte boundary.
+ */
+ mctx = (struct mcontext __user *)
+ ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
+ if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size)
+ || save_user_regs(regs, mctx, 0, ctx_has_vsx_region)
+ || put_sigset_t(&old_ctx->uc_sigmask, &current->blocked)
+ || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
+ return -EFAULT;
+ }
+ if (new_ctx == NULL)
+ return 0;
+ if (!access_ok(VERIFY_READ, new_ctx, ctx_size)
+ || __get_user(tmp, (u8 __user *) new_ctx)
+ || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
+ return -EFAULT;
+
+ /*
+ * If we get a fault copying the context into the kernel's
+ * image of the user's registers, we can't just return -EFAULT
+ * because the user's registers will be corrupted. For instance
+ * the NIP value may have been updated but not some of the
+ * other registers. Given that we have done the access_ok
+ * and successfully read the first and last bytes of the region
+ * above, this should only happen in an out-of-memory situation
+ * or if another thread unmaps the region containing the context.
+ * We kill the task with a SIGSEGV in this situation.
+ */
+ if (do_setcontext(new_ctx, regs, 0))
+ do_exit(SIGSEGV);
+
+ set_thread_flag(TIF_RESTOREALL);
+ return 0;
+}
+
+long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
+ struct pt_regs *regs)
+{
+ struct rt_sigframe __user *rt_sf;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+ rt_sf = (struct rt_sigframe __user *)
+ (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
+ if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
+ goto bad;
+ if (do_setcontext(&rt_sf->uc, regs, 1))
+ goto bad;
+
+ /*
+ * It's not clear whether or why it is desirable to save the
+ * sigaltstack setting on signal delivery and restore it on
+ * signal return. But other architectures do this and we have
+ * always done it up until now so it is probably better not to
+ * change it. -- paulus
+ */
+#ifdef CONFIG_PPC64
+ /*
+ * We use the compat_sys_ version that does the 32/64 bits conversion
+ * and takes userland pointer directly. What about error checking ?
+ * nobody does any...
+ */
+ compat_sys_sigaltstack((u32)(u64)&rt_sf->uc.uc_stack, 0, 0, 0, 0, 0, regs);
+#else
+ do_sigaltstack(&rt_sf->uc.uc_stack, NULL, regs->gpr[1]);
+#endif
+ set_thread_flag(TIF_RESTOREALL);
+ return 0;
+
+ bad:
+ if (show_unhandled_signals)
+ printk_ratelimited(KERN_INFO
+ "%s[%d]: bad frame in sys_rt_sigreturn: "
+ "%p nip %08lx lr %08lx\n",
+ current->comm, current->pid,
+ rt_sf, regs->nip, regs->link);
+
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+#ifdef CONFIG_PPC32
+int sys_debug_setcontext(struct ucontext __user *ctx,
+ int ndbg, struct sig_dbg_op __user *dbg,
+ int r6, int r7, int r8,
+ struct pt_regs *regs)
+{
+ struct sig_dbg_op op;
+ int i;
+ unsigned char tmp;
+ unsigned long new_msr = regs->msr;
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
+ unsigned long new_dbcr0 = current->thread.dbcr0;
+#endif
+
+ for (i=0; i<ndbg; i++) {
+ if (copy_from_user(&op, dbg + i, sizeof(op)))
+ return -EFAULT;
+ switch (op.dbg_type) {
+ case SIG_DBG_SINGLE_STEPPING:
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
+ if (op.dbg_value) {
+ new_msr |= MSR_DE;
+ new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
+ } else {
+ new_dbcr0 &= ~DBCR0_IC;
+ if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
+ current->thread.dbcr1)) {
+ new_msr &= ~MSR_DE;
+ new_dbcr0 &= ~DBCR0_IDM;
+ }
+ }
+#else
+ if (op.dbg_value)
+ new_msr |= MSR_SE;
+ else
+ new_msr &= ~MSR_SE;
+#endif
+ break;
+ case SIG_DBG_BRANCH_TRACING:
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
+ return -EINVAL;
+#else
+ if (op.dbg_value)
+ new_msr |= MSR_BE;
+ else
+ new_msr &= ~MSR_BE;
+#endif
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ /* We wait until here to actually install the values in the
+ registers so if we fail in the above loop, it will not
+ affect the contents of these registers. After this point,
+ failure is a problem, anyway, and it's very unlikely unless
+ the user is really doing something wrong. */
+ regs->msr = new_msr;
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
+ current->thread.dbcr0 = new_dbcr0;
+#endif
+
+ if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx))
+ || __get_user(tmp, (u8 __user *) ctx)
+ || __get_user(tmp, (u8 __user *) (ctx + 1) - 1))
+ return -EFAULT;
+
+ /*
+ * If we get a fault copying the context into the kernel's
+ * image of the user's registers, we can't just return -EFAULT
+ * because the user's registers will be corrupted. For instance
+ * the NIP value may have been updated but not some of the
+ * other registers. Given that we have done the access_ok
+ * and successfully read the first and last bytes of the region
+ * above, this should only happen in an out-of-memory situation
+ * or if another thread unmaps the region containing the context.
+ * We kill the task with a SIGSEGV in this situation.
+ */
+ if (do_setcontext(ctx, regs, 1)) {
+ if (show_unhandled_signals)
+ printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
+ "sys_debug_setcontext: %p nip %08lx "
+ "lr %08lx\n",
+ current->comm, current->pid,
+ ctx, regs->nip, regs->link);
+
+ force_sig(SIGSEGV, current);
+ goto out;
+ }
+
+ /*
+ * It's not clear whether or why it is desirable to save the
+ * sigaltstack setting on signal delivery and restore it on
+ * signal return. But other architectures do this and we have
+ * always done it up until now so it is probably better not to
+ * change it. -- paulus
+ */
+ do_sigaltstack(&ctx->uc_stack, NULL, regs->gpr[1]);
+
+ set_thread_flag(TIF_RESTOREALL);
+ out:
+ return 0;
+}
+#endif
+
+/*
+ * OK, we're invoking a handler
+ */
+int handle_signal32(unsigned long sig, struct k_sigaction *ka,
+ siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
+{
+ struct sigcontext __user *sc;
+ struct sigframe __user *frame;
+ unsigned long newsp = 0;
+
+ /* Set up Signal Frame */
+ frame = get_sigframe(ka, regs, sizeof(*frame), 1);
+ if (unlikely(frame == NULL))
+ goto badframe;
+ sc = (struct sigcontext __user *) &frame->sctx;
+
+#if _NSIG != 64
+#error "Please adjust handle_signal()"
+#endif
+ if (__put_user(to_user_ptr(ka->sa.sa_handler), &sc->handler)
+ || __put_user(oldset->sig[0], &sc->oldmask)
+#ifdef CONFIG_PPC64
+ || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
+#else
+ || __put_user(oldset->sig[1], &sc->_unused[3])
+#endif
+ || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
+ || __put_user(sig, &sc->signal))
+ goto badframe;
+
+ if (vdso32_sigtramp && current->mm->context.vdso_base) {
+ if (save_user_regs(regs, &frame->mctx, 0, 1))
+ goto badframe;
+ regs->link = current->mm->context.vdso_base + vdso32_sigtramp;
+ } else {
+ if (save_user_regs(regs, &frame->mctx, __NR_sigreturn, 1))
+ goto badframe;
+ regs->link = (unsigned long) frame->mctx.tramp;
+ }
+
+ current->thread.fpscr.val = 0; /* turn off all fp exceptions */
+
+ /* create a stack frame for the caller of the handler */
+ newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
+ if (put_user(regs->gpr[1], (u32 __user *)newsp))
+ goto badframe;
+
+ regs->gpr[1] = newsp;
+ regs->gpr[3] = sig;
+ regs->gpr[4] = (unsigned long) sc;
+ regs->nip = (unsigned long) ka->sa.sa_handler;
+ /* enter the signal handler in big-endian mode */
+ regs->msr &= ~MSR_LE;
+
+ return 1;
+
+badframe:
+#ifdef DEBUG_SIG
+ printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n",
+ regs, frame, newsp);
+#endif
+ if (show_unhandled_signals)
+ printk_ratelimited(KERN_INFO
+ "%s[%d]: bad frame in handle_signal32: "
+ "%p nip %08lx lr %08lx\n",
+ current->comm, current->pid,
+ frame, regs->nip, regs->link);
+
+ force_sigsegv(sig, current);
+ return 0;
+}
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
+ struct pt_regs *regs)
+{
+ struct sigcontext __user *sc;
+ struct sigcontext sigctx;
+ struct mcontext __user *sr;
+ void __user *addr;
+ sigset_t set;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+ sc = (struct sigcontext __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
+ addr = sc;
+ if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
+ goto badframe;
+
+#ifdef CONFIG_PPC64
+ /*
+ * Note that PPC32 puts the upper 32 bits of the sigmask in the
+ * unused part of the signal stackframe
+ */
+ set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
+#else
+ set.sig[0] = sigctx.oldmask;
+ set.sig[1] = sigctx._unused[3];
+#endif
+ restore_sigmask(&set);
+
+ sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
+ addr = sr;
+ if (!access_ok(VERIFY_READ, sr, sizeof(*sr))
+ || restore_user_regs(regs, sr, 1))
+ goto badframe;
+
+ set_thread_flag(TIF_RESTOREALL);
+ return 0;
+
+badframe:
+ if (show_unhandled_signals)
+ printk_ratelimited(KERN_INFO
+ "%s[%d]: bad frame in sys_sigreturn: "
+ "%p nip %08lx lr %08lx\n",
+ current->comm, current->pid,
+ addr, regs->nip, regs->link);
+
+ force_sig(SIGSEGV, current);
+ return 0;
+}