1 /*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <signal.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <unistd.h>
21
22 #include "jni.h"
23
24 #include <sys/ucontext.h>
25
26 static int signal_count;
27 static const int kMaxSignal = 2;
28
29 #if defined(__i386__) || defined(__x86_64__)
30 #if defined(__APPLE__)
31 #define ucontext __darwin_ucontext
32
33 #if defined(__x86_64__)
34 // 64 bit mac build.
35 #define CTX_EIP uc_mcontext->__ss.__rip
36 #else
37 // 32 bit mac build.
38 #define CTX_EIP uc_mcontext->__ss.__eip
39 #endif
40
41 #elif defined(__x86_64__)
42 // 64 bit linux build.
43 #define CTX_EIP uc_mcontext.gregs[REG_RIP]
44 #else
45 // 32 bit linux build.
46 #define CTX_EIP uc_mcontext.gregs[REG_EIP]
47 #endif
48 #endif
49
signalhandler(int sig,siginfo_t * info,void * context)50 static void signalhandler(int sig, siginfo_t* info, void* context) {
51 printf("signal caught\n");
52 ++signal_count;
53 if (signal_count > kMaxSignal) {
54 abort();
55 }
56 #if defined(__arm__)
57 struct ucontext *uc = reinterpret_cast<struct ucontext*>(context);
58 struct sigcontext *sc = reinterpret_cast<struct sigcontext*>(&uc->uc_mcontext);
59 sc->arm_pc += 2; // Skip instruction causing segv.
60 #elif defined(__aarch64__)
61 struct ucontext *uc = reinterpret_cast<struct ucontext*>(context);
62 struct sigcontext *sc = reinterpret_cast<struct sigcontext*>(&uc->uc_mcontext);
63 sc->pc += 4; // Skip instruction causing segv.
64 #elif defined(__i386__) || defined(__x86_64__)
65 struct ucontext *uc = reinterpret_cast<struct ucontext*>(context);
66 uc->CTX_EIP += 3;
67 #endif
68 }
69
70 static struct sigaction oldaction;
71
Java_Main_initSignalTest(JNIEnv *,jclass)72 extern "C" JNIEXPORT void JNICALL Java_Main_initSignalTest(JNIEnv*, jclass) {
73 struct sigaction action;
74 action.sa_sigaction = signalhandler;
75 sigemptyset(&action.sa_mask);
76 action.sa_flags = SA_SIGINFO | SA_ONSTACK;
77 #if !defined(__APPLE__) && !defined(__mips__)
78 action.sa_restorer = nullptr;
79 #endif
80
81 sigaction(SIGSEGV, &action, &oldaction);
82 }
83
Java_Main_terminateSignalTest(JNIEnv *,jclass)84 extern "C" JNIEXPORT void JNICALL Java_Main_terminateSignalTest(JNIEnv*, jclass) {
85 sigaction(SIGSEGV, &oldaction, nullptr);
86 }
87
88 // Prevent the compiler being a smart-alec and optimizing out the assignment
89 // to nullptr.
90 char *p = nullptr;
91
Java_Main_testSignal(JNIEnv *,jclass)92 extern "C" JNIEXPORT jint JNICALL Java_Main_testSignal(JNIEnv*, jclass) {
93 #if defined(__arm__) || defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
94 // On supported architectures we cause a real SEGV.
95 *p = 'a';
96 #else
97 // On other architectures we simulate SEGV.
98 kill(getpid(), SIGSEGV);
99 #endif
100 return 1234;
101 }
102
103