LXR linux/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_missing

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2019 ARM Limited
   4 *
   5 * Place a fake sigframe on the stack missing the mandatory FPSIMD
   6 * record: on sigreturn Kernel must spot this attempt and the test
   7 * case is expected to be terminated via SEGV.
   8 */
   9
  10#include <stdio.h>
  11#include <signal.h>
  12#include <ucontext.h>
  13
  14#include "test_signals_utils.h"
  15#include "testcases.h"
  16
  17struct fake_sigframe sf;
  18
  19static int fake_sigreturn_missing_fpsimd_run(struct tdescr *td,
  20                                             siginfo_t *si, ucontext_t *uc)
  21{
  22        size_t resv_sz, offset;
  23        struct _aarch64_ctx *head = GET_SF_RESV_HEAD(sf);
  24
  25        /* just to fill the ucontext_t with something real */
  26        if (!get_current_context(td, &sf.uc))
  27                return 1;
  28
  29        resv_sz = GET_SF_RESV_SIZE(sf);
  30        head = get_header(head, FPSIMD_MAGIC, resv_sz, &offset);
  31        if (head && resv_sz - offset >= HDR_SZ) {
  32                fprintf(stderr, "Mangling template header. Spare space:%zd\n",
  33                        resv_sz - offset);
  34                /* Just overwrite fpsmid_context */
  35                write_terminator_record(head);
  36
  37                ASSERT_BAD_CONTEXT(&sf.uc);
  38                fake_sigreturn(&sf, sizeof(sf), 0);
  39        }
  40
  41        return 1;
  42}
  43
  44struct tdescr tde = {
  45                .name = "FAKE_SIGRETURN_MISSING_FPSIMD",
  46                .descr = "Triggers a sigreturn with a missing fpsimd_context",
  47                .sig_ok = SIGSEGV,
  48                .timeout = 3,
  49                .run = fake_sigreturn_missing_fpsimd_run,
  50};
  51