v4.19.13 snapshot.
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
new file mode 100644
index 0000000..b8f766c
--- /dev/null
+++ b/arch/arm/kernel/signal.c
@@ -0,0 +1,719 @@
+/*
+ * linux/arch/arm/kernel/signal.c
+ *
+ * Copyright (C) 1995-2009 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/errno.h>
+#include <linux/random.h>
+#include <linux/signal.h>
+#include <linux/personality.h>
+#include <linux/uaccess.h>
+#include <linux/tracehook.h>
+#include <linux/uprobes.h>
+#include <linux/syscalls.h>
+
+#include <asm/elf.h>
+#include <asm/cacheflush.h>
+#include <asm/traps.h>
+#include <asm/unistd.h>
+#include <asm/vfp.h>
+
+#include "signal.h"
+
+extern const unsigned long sigreturn_codes[17];
+
+static unsigned long signal_return_offset;
+
+#ifdef CONFIG_CRUNCH
+static int preserve_crunch_context(struct crunch_sigframe __user *frame)
+{
+ char kbuf[sizeof(*frame) + 8];
+ struct crunch_sigframe *kframe;
+
+ /* the crunch context must be 64 bit aligned */
+ kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7);
+ kframe->magic = CRUNCH_MAGIC;
+ kframe->size = CRUNCH_STORAGE_SIZE;
+ crunch_task_copy(current_thread_info(), &kframe->storage);
+ return __copy_to_user(frame, kframe, sizeof(*frame));
+}
+
+static int restore_crunch_context(char __user **auxp)
+{
+ struct crunch_sigframe __user *frame =
+ (struct crunch_sigframe __user *)*auxp;
+ char kbuf[sizeof(*frame) + 8];
+ struct crunch_sigframe *kframe;
+
+ /* the crunch context must be 64 bit aligned */
+ kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7);
+ if (__copy_from_user(kframe, frame, sizeof(*frame)))
+ return -1;
+ if (kframe->magic != CRUNCH_MAGIC ||
+ kframe->size != CRUNCH_STORAGE_SIZE)
+ return -1;
+ *auxp += CRUNCH_STORAGE_SIZE;
+ crunch_task_restore(current_thread_info(), &kframe->storage);
+ return 0;
+}
+#endif
+
+#ifdef CONFIG_IWMMXT
+
+static int preserve_iwmmxt_context(struct iwmmxt_sigframe __user *frame)
+{
+ char kbuf[sizeof(*frame) + 8];
+ struct iwmmxt_sigframe *kframe;
+ int err = 0;
+
+ /* the iWMMXt context must be 64 bit aligned */
+ kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
+
+ if (test_thread_flag(TIF_USING_IWMMXT)) {
+ kframe->magic = IWMMXT_MAGIC;
+ kframe->size = IWMMXT_STORAGE_SIZE;
+ iwmmxt_task_copy(current_thread_info(), &kframe->storage);
+
+ err = __copy_to_user(frame, kframe, sizeof(*frame));
+ } else {
+ /*
+ * For bug-compatibility with older kernels, some space
+ * has to be reserved for iWMMXt even if it's not used.
+ * Set the magic and size appropriately so that properly
+ * written userspace can skip it reliably:
+ */
+ __put_user_error(DUMMY_MAGIC, &frame->magic, err);
+ __put_user_error(IWMMXT_STORAGE_SIZE, &frame->size, err);
+ }
+
+ return err;
+}
+
+static int restore_iwmmxt_context(char __user **auxp)
+{
+ struct iwmmxt_sigframe __user *frame =
+ (struct iwmmxt_sigframe __user *)*auxp;
+ char kbuf[sizeof(*frame) + 8];
+ struct iwmmxt_sigframe *kframe;
+
+ /* the iWMMXt context must be 64 bit aligned */
+ kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
+ if (__copy_from_user(kframe, frame, sizeof(*frame)))
+ return -1;
+
+ /*
+ * For non-iWMMXt threads: a single iwmmxt_sigframe-sized dummy
+ * block is discarded for compatibility with setup_sigframe() if
+ * present, but we don't mandate its presence. If some other
+ * magic is here, it's not for us:
+ */
+ if (!test_thread_flag(TIF_USING_IWMMXT) &&
+ kframe->magic != DUMMY_MAGIC)
+ return 0;
+
+ if (kframe->size != IWMMXT_STORAGE_SIZE)
+ return -1;
+
+ if (test_thread_flag(TIF_USING_IWMMXT)) {
+ if (kframe->magic != IWMMXT_MAGIC)
+ return -1;
+
+ iwmmxt_task_restore(current_thread_info(), &kframe->storage);
+ }
+
+ *auxp += IWMMXT_STORAGE_SIZE;
+ return 0;
+}
+
+#endif
+
+#ifdef CONFIG_VFP
+
+static int preserve_vfp_context(struct vfp_sigframe __user *frame)
+{
+ const unsigned long magic = VFP_MAGIC;
+ const unsigned long size = VFP_STORAGE_SIZE;
+ int err = 0;
+
+ __put_user_error(magic, &frame->magic, err);
+ __put_user_error(size, &frame->size, err);
+
+ if (err)
+ return -EFAULT;
+
+ return vfp_preserve_user_clear_hwstate(&frame->ufp, &frame->ufp_exc);
+}
+
+static int restore_vfp_context(char __user **auxp)
+{
+ struct vfp_sigframe frame;
+ int err;
+
+ err = __copy_from_user(&frame, *auxp, sizeof(frame));
+ if (err)
+ return err;
+
+ if (frame.magic != VFP_MAGIC || frame.size != VFP_STORAGE_SIZE)
+ return -EINVAL;
+
+ *auxp += sizeof(frame);
+ return vfp_restore_user_hwstate(&frame.ufp, &frame.ufp_exc);
+}
+
+#endif
+
+/*
+ * Do a signal return; undo the signal stack. These are aligned to 64-bit.
+ */
+
+static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
+{
+ struct sigcontext context;
+ char __user *aux;
+ sigset_t set;
+ int err;
+
+ err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
+ if (err == 0)
+ set_current_blocked(&set);
+
+ err |= __copy_from_user(&context, &sf->uc.uc_mcontext, sizeof(context));
+ if (err == 0) {
+ regs->ARM_r0 = context.arm_r0;
+ regs->ARM_r1 = context.arm_r1;
+ regs->ARM_r2 = context.arm_r2;
+ regs->ARM_r3 = context.arm_r3;
+ regs->ARM_r4 = context.arm_r4;
+ regs->ARM_r5 = context.arm_r5;
+ regs->ARM_r6 = context.arm_r6;
+ regs->ARM_r7 = context.arm_r7;
+ regs->ARM_r8 = context.arm_r8;
+ regs->ARM_r9 = context.arm_r9;
+ regs->ARM_r10 = context.arm_r10;
+ regs->ARM_fp = context.arm_fp;
+ regs->ARM_ip = context.arm_ip;
+ regs->ARM_sp = context.arm_sp;
+ regs->ARM_lr = context.arm_lr;
+ regs->ARM_pc = context.arm_pc;
+ regs->ARM_cpsr = context.arm_cpsr;
+ }
+
+ err |= !valid_user_regs(regs);
+
+ aux = (char __user *) sf->uc.uc_regspace;
+#ifdef CONFIG_CRUNCH
+ if (err == 0)
+ err |= restore_crunch_context(&aux);
+#endif
+#ifdef CONFIG_IWMMXT
+ if (err == 0)
+ err |= restore_iwmmxt_context(&aux);
+#endif
+#ifdef CONFIG_VFP
+ if (err == 0)
+ err |= restore_vfp_context(&aux);
+#endif
+
+ return err;
+}
+
+asmlinkage int sys_sigreturn(struct pt_regs *regs)
+{
+ struct sigframe __user *frame;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ /*
+ * Since we stacked the signal on a 64-bit boundary,
+ * then 'sp' should be word aligned here. If it's
+ * not, then the user is trying to mess with us.
+ */
+ if (regs->ARM_sp & 7)
+ goto badframe;
+
+ frame = (struct sigframe __user *)regs->ARM_sp;
+
+ if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
+ goto badframe;
+
+ if (restore_sigframe(regs, frame))
+ goto badframe;
+
+ return regs->ARM_r0;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
+{
+ struct rt_sigframe __user *frame;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ /*
+ * Since we stacked the signal on a 64-bit boundary,
+ * then 'sp' should be word aligned here. If it's
+ * not, then the user is trying to mess with us.
+ */
+ if (regs->ARM_sp & 7)
+ goto badframe;
+
+ frame = (struct rt_sigframe __user *)regs->ARM_sp;
+
+ if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
+ goto badframe;
+
+ if (restore_sigframe(regs, &frame->sig))
+ goto badframe;
+
+ if (restore_altstack(&frame->sig.uc.uc_stack))
+ goto badframe;
+
+ return regs->ARM_r0;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+static int
+setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set)
+{
+ struct aux_sigframe __user *aux;
+ int err = 0;
+
+ __put_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err);
+ __put_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err);
+ __put_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err);
+ __put_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err);
+ __put_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err);
+ __put_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err);
+ __put_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err);
+ __put_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err);
+ __put_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err);
+ __put_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err);
+ __put_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err);
+ __put_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err);
+ __put_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err);
+ __put_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err);
+ __put_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err);
+ __put_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err);
+ __put_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err);
+
+ __put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no, err);
+ __put_user_error(current->thread.error_code, &sf->uc.uc_mcontext.error_code, err);
+ __put_user_error(current->thread.address, &sf->uc.uc_mcontext.fault_address, err);
+ __put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err);
+
+ err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
+
+ aux = (struct aux_sigframe __user *) sf->uc.uc_regspace;
+#ifdef CONFIG_CRUNCH
+ if (err == 0)
+ err |= preserve_crunch_context(&aux->crunch);
+#endif
+#ifdef CONFIG_IWMMXT
+ if (err == 0)
+ err |= preserve_iwmmxt_context(&aux->iwmmxt);
+#endif
+#ifdef CONFIG_VFP
+ if (err == 0)
+ err |= preserve_vfp_context(&aux->vfp);
+#endif
+ __put_user_error(0, &aux->end_magic, err);
+
+ return err;
+}
+
+static inline void __user *
+get_sigframe(struct ksignal *ksig, struct pt_regs *regs, int framesize)
+{
+ unsigned long sp = sigsp(regs->ARM_sp, ksig);
+ void __user *frame;
+
+ /*
+ * ATPCS B01 mandates 8-byte alignment
+ */
+ frame = (void __user *)((sp - framesize) & ~7);
+
+ /*
+ * Check that we can actually write to the signal frame.
+ */
+ if (!access_ok(VERIFY_WRITE, frame, framesize))
+ frame = NULL;
+
+ return frame;
+}
+
+static int
+setup_return(struct pt_regs *regs, struct ksignal *ksig,
+ unsigned long __user *rc, void __user *frame)
+{
+ unsigned long handler = (unsigned long)ksig->ka.sa.sa_handler;
+ unsigned long handler_fdpic_GOT = 0;
+ unsigned long retcode;
+ unsigned int idx, thumb = 0;
+ unsigned long cpsr = regs->ARM_cpsr & ~(PSR_f | PSR_E_BIT);
+ bool fdpic = IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&
+ (current->personality & FDPIC_FUNCPTRS);
+
+ if (fdpic) {
+ unsigned long __user *fdpic_func_desc =
+ (unsigned long __user *)handler;
+ if (__get_user(handler, &fdpic_func_desc[0]) ||
+ __get_user(handler_fdpic_GOT, &fdpic_func_desc[1]))
+ return 1;
+ }
+
+ cpsr |= PSR_ENDSTATE;
+
+ /*
+ * Maybe we need to deliver a 32-bit signal to a 26-bit task.
+ */
+ if (ksig->ka.sa.sa_flags & SA_THIRTYTWO)
+ cpsr = (cpsr & ~MODE_MASK) | USR_MODE;
+
+#ifdef CONFIG_ARM_THUMB
+ if (elf_hwcap & HWCAP_THUMB) {
+ /*
+ * The LSB of the handler determines if we're going to
+ * be using THUMB or ARM mode for this signal handler.
+ */
+ thumb = handler & 1;
+
+ /*
+ * Clear the If-Then Thumb-2 execution state. ARM spec
+ * requires this to be all 000s in ARM mode. Snapdragon
+ * S4/Krait misbehaves on a Thumb=>ARM signal transition
+ * without this.
+ *
+ * We must do this whenever we are running on a Thumb-2
+ * capable CPU, which includes ARMv6T2. However, we elect
+ * to always do this to simplify the code; this field is
+ * marked UNK/SBZP for older architectures.
+ */
+ cpsr &= ~PSR_IT_MASK;
+
+ if (thumb) {
+ cpsr |= PSR_T_BIT;
+ } else
+ cpsr &= ~PSR_T_BIT;
+ }
+#endif
+
+ if (ksig->ka.sa.sa_flags & SA_RESTORER) {
+ retcode = (unsigned long)ksig->ka.sa.sa_restorer;
+ if (fdpic) {
+ /*
+ * We need code to load the function descriptor.
+ * That code follows the standard sigreturn code
+ * (6 words), and is made of 3 + 2 words for each
+ * variant. The 4th copied word is the actual FD
+ * address that the assembly code expects.
+ */
+ idx = 6 + thumb * 3;
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+ idx += 5;
+ if (__put_user(sigreturn_codes[idx], rc ) ||
+ __put_user(sigreturn_codes[idx+1], rc+1) ||
+ __put_user(sigreturn_codes[idx+2], rc+2) ||
+ __put_user(retcode, rc+3))
+ return 1;
+ goto rc_finish;
+ }
+ } else {
+ idx = thumb << 1;
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+ idx += 3;
+
+ /*
+ * Put the sigreturn code on the stack no matter which return
+ * mechanism we use in order to remain ABI compliant
+ */
+ if (__put_user(sigreturn_codes[idx], rc) ||
+ __put_user(sigreturn_codes[idx+1], rc+1))
+ return 1;
+
+rc_finish:
+#ifdef CONFIG_MMU
+ if (cpsr & MODE32_BIT) {
+ struct mm_struct *mm = current->mm;
+
+ /*
+ * 32-bit code can use the signal return page
+ * except when the MPU has protected the vectors
+ * page from PL0
+ */
+ retcode = mm->context.sigpage + signal_return_offset +
+ (idx << 2) + thumb;
+ } else
+#endif
+ {
+ /*
+ * Ensure that the instruction cache sees
+ * the return code written onto the stack.
+ */
+ flush_icache_range((unsigned long)rc,
+ (unsigned long)(rc + 3));
+
+ retcode = ((unsigned long)rc) + thumb;
+ }
+ }
+
+ regs->ARM_r0 = ksig->sig;
+ regs->ARM_sp = (unsigned long)frame;
+ regs->ARM_lr = retcode;
+ regs->ARM_pc = handler;
+ if (fdpic)
+ regs->ARM_r9 = handler_fdpic_GOT;
+ regs->ARM_cpsr = cpsr;
+
+ return 0;
+}
+
+static int
+setup_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs)
+{
+ struct sigframe __user *frame = get_sigframe(ksig, regs, sizeof(*frame));
+ int err = 0;
+
+ if (!frame)
+ return 1;
+
+ /*
+ * Set uc.uc_flags to a value which sc.trap_no would never have.
+ */
+ __put_user_error(0x5ac3c35a, &frame->uc.uc_flags, err);
+
+ err |= setup_sigframe(frame, regs, set);
+ if (err == 0)
+ err = setup_return(regs, ksig, frame->retcode, frame);
+
+ return err;
+}
+
+static int
+setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs)
+{
+ struct rt_sigframe __user *frame = get_sigframe(ksig, regs, sizeof(*frame));
+ int err = 0;
+
+ if (!frame)
+ return 1;
+
+ err |= copy_siginfo_to_user(&frame->info, &ksig->info);
+
+ __put_user_error(0, &frame->sig.uc.uc_flags, err);
+ __put_user_error(NULL, &frame->sig.uc.uc_link, err);
+
+ err |= __save_altstack(&frame->sig.uc.uc_stack, regs->ARM_sp);
+ err |= setup_sigframe(&frame->sig, regs, set);
+ if (err == 0)
+ err = setup_return(regs, ksig, frame->sig.retcode, frame);
+
+ if (err == 0) {
+ /*
+ * For realtime signals we must also set the second and third
+ * arguments for the signal handler.
+ * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06
+ */
+ regs->ARM_r1 = (unsigned long)&frame->info;
+ regs->ARM_r2 = (unsigned long)&frame->sig.uc;
+ }
+
+ return err;
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
+{
+ sigset_t *oldset = sigmask_to_save();
+ int ret;
+
+ /*
+ * Increment event counter and perform fixup for the pre-signal
+ * frame.
+ */
+ rseq_signal_deliver(ksig, regs);
+
+ /*
+ * Set up the stack frame
+ */
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+ ret = setup_rt_frame(ksig, oldset, regs);
+ else
+ ret = setup_frame(ksig, oldset, regs);
+
+ /*
+ * Check that the resulting registers are actually sane.
+ */
+ ret |= !valid_user_regs(regs);
+
+ signal_setup_done(ret, ksig, 0);
+}
+
+/*
+ * Note that 'init' is a special process: it doesn't get signals it doesn't
+ * want to handle. Thus you cannot kill init even with a SIGKILL even by
+ * mistake.
+ *
+ * Note that we go through the signals twice: once to check the signals that
+ * the kernel can handle, and then we build all the user-level signal handling
+ * stack-frames in one go after that.
+ */
+static int do_signal(struct pt_regs *regs, int syscall)
+{
+ unsigned int retval = 0, continue_addr = 0, restart_addr = 0;
+ struct ksignal ksig;
+ int restart = 0;
+
+ /*
+ * If we were from a system call, check for system call restarting...
+ */
+ if (syscall) {
+ continue_addr = regs->ARM_pc;
+ restart_addr = continue_addr - (thumb_mode(regs) ? 2 : 4);
+ retval = regs->ARM_r0;
+
+ /*
+ * Prepare for system call restart. We do this here so that a
+ * debugger will see the already changed PSW.
+ */
+ switch (retval) {
+ case -ERESTART_RESTARTBLOCK:
+ restart -= 2;
+ case -ERESTARTNOHAND:
+ case -ERESTARTSYS:
+ case -ERESTARTNOINTR:
+ restart++;
+ regs->ARM_r0 = regs->ARM_ORIG_r0;
+ regs->ARM_pc = restart_addr;
+ break;
+ }
+ }
+
+ /*
+ * Get the signal to deliver. When running under ptrace, at this
+ * point the debugger may change all our registers ...
+ */
+ /*
+ * Depending on the signal settings we may need to revert the
+ * decision to restart the system call. But skip this if a
+ * debugger has chosen to restart at a different PC.
+ */
+ if (get_signal(&ksig)) {
+ /* handler */
+ if (unlikely(restart) && regs->ARM_pc == restart_addr) {
+ if (retval == -ERESTARTNOHAND ||
+ retval == -ERESTART_RESTARTBLOCK
+ || (retval == -ERESTARTSYS
+ && !(ksig.ka.sa.sa_flags & SA_RESTART))) {
+ regs->ARM_r0 = -EINTR;
+ regs->ARM_pc = continue_addr;
+ }
+ }
+ handle_signal(&ksig, regs);
+ } else {
+ /* no handler */
+ restore_saved_sigmask();
+ if (unlikely(restart) && regs->ARM_pc == restart_addr) {
+ regs->ARM_pc = continue_addr;
+ return restart;
+ }
+ }
+ return 0;
+}
+
+asmlinkage int
+do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
+{
+ /*
+ * The assembly code enters us with IRQs off, but it hasn't
+ * informed the tracing code of that for efficiency reasons.
+ * Update the trace code with the current status.
+ */
+ trace_hardirqs_off();
+ do {
+ if (likely(thread_flags & _TIF_NEED_RESCHED)) {
+ schedule();
+ } else {
+ if (unlikely(!user_mode(regs)))
+ return 0;
+ local_irq_enable();
+ if (thread_flags & _TIF_SIGPENDING) {
+ int restart = do_signal(regs, syscall);
+ if (unlikely(restart)) {
+ /*
+ * Restart without handlers.
+ * Deal with it without leaving
+ * the kernel space.
+ */
+ return restart;
+ }
+ syscall = 0;
+ } else if (thread_flags & _TIF_UPROBE) {
+ uprobe_notify_resume(regs);
+ } else {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ rseq_handle_notify_resume(NULL, regs);
+ }
+ }
+ local_irq_disable();
+ thread_flags = current_thread_info()->flags;
+ } while (thread_flags & _TIF_WORK_MASK);
+ return 0;
+}
+
+struct page *get_signal_page(void)
+{
+ unsigned long ptr;
+ unsigned offset;
+ struct page *page;
+ void *addr;
+
+ page = alloc_pages(GFP_KERNEL, 0);
+
+ if (!page)
+ return NULL;
+
+ addr = page_address(page);
+
+ /* Give the signal return code some randomness */
+ offset = 0x200 + (get_random_int() & 0x7fc);
+ signal_return_offset = offset;
+
+ /*
+ * Copy signal return handlers into the vector page, and
+ * set sigreturn to be a pointer to these.
+ */
+ memcpy(addr + offset, sigreturn_codes, sizeof(sigreturn_codes));
+
+ ptr = (unsigned long)addr + offset;
+ flush_icache_range(ptr, ptr + sizeof(sigreturn_codes));
+
+ return page;
+}
+
+/* Defer to generic check */
+asmlinkage void addr_limit_check_failed(void)
+{
+ addr_limit_user_check();
+}
+
+#ifdef CONFIG_DEBUG_RSEQ
+asmlinkage void do_rseq_syscall(struct pt_regs *regs)
+{
+ rseq_syscall(regs);
+}
+#endif