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

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2019 ARM Limited
   4 *
   5 * Place a fake sigframe on the stack including a BAD Unknown magic
   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 <signal.h>
  11#include <ucontext.h>
  12
  13#include "test_signals_utils.h"
  14#include "testcases.h"
  15
  16struct fake_sigframe sf;
  17
  18static int fake_sigreturn_bad_magic_run(struct tdescr *td,
  19                                        siginfo_t *si, ucontext_t *uc)
  20{
  21        struct _aarch64_ctx *shead = GET_SF_RESV_HEAD(sf), *head;
  22
  23        /* just to fill the ucontext_t with something real */
  24        if (!get_current_context(td, &sf.uc))
  25                return 1;
  26
  27        /* need at least 2*HDR_SZ space: KSFT_BAD_MAGIC + terminator. */
  28        head = get_starting_head(shead, HDR_SZ * 2, GET_SF_RESV_SIZE(sf), NULL);
  29        if (!head)
  30                return 0;
  31
  32        /*
  33         * use a well known NON existent bad magic...something
  34         * we should pretty sure won't be ever defined in Kernel
  35         */
  36        head->magic = KSFT_BAD_MAGIC;
  37        head->size = HDR_SZ;
  38        write_terminator_record(GET_RESV_NEXT_HEAD(head));
  39
  40        ASSERT_BAD_CONTEXT(&sf.uc);
  41        fake_sigreturn(&sf, sizeof(sf), 0);
  42
  43        return 1;
  44}
  45
  46struct tdescr tde = {
  47                .name = "FAKE_SIGRETURN_BAD_MAGIC",
  48                .descr = "Trigger a sigreturn with a sigframe with a bad magic",
  49                .sig_ok = SIGSEGV,
  50                .timeout = 3,
  51                .run = fake_sigreturn_bad_magic_run,
  52};
  53