Fatal signal 11 (SIGSEGV) at 0xdeadbaad (code=1) 错误 解决方案(android-ndk)

在android里做ndk编程的时候，碰到个随机性错误

错误信息如下：

05-06 15:59:44.411: A/libc(3347): Fatal signal 11 (SIGSEGV) at 0xdeadbaad (code=1)
05-06 15:59:44.911: I/DEBUG(3344): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
05-06 15:59:44.911: I/DEBUG(3344): Build fingerprint: 'i.Kan/full_godbox/godbox:4.0.3/IML74K/eng.mipt.20130428.110435:eng/test-keys'
05-06 15:59:44.911: I/DEBUG(3344): pid: 3347, tid: 3348  >>> com.nef.xxx <<<
05-06 15:59:44.911: I/DEBUG(3344): signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr deadbaad
05-06 15:59:44.911: I/DEBUG(3344):  r0 deadbaad  r1 00d9c060  r2 40000000  r3 00000000
05-06 15:59:44.911: I/DEBUG(3344):  r4 00000000  r5 00000027  r6 415bf010  r7 00000062
05-06 15:59:44.911: I/DEBUG(3344):  r8 415bf018  r9 00000047  10 100ffb94  fp 100ffbd8
05-06 15:59:44.911: I/DEBUG(3344):  ip ffffffff  sp 100ffb50  lr 40071121  pc 4006d880  cpsr 60000030
05-06 15:59:44.911: I/DEBUG(3344):  d0  400000003eaaaaab  d1  3ff000003f800000
05-06 15:59:44.911: I/DEBUG(3344):  d2  457ff80000000fff  d3  000000003f000000
05-06 15:59:44.911: I/DEBUG(3344):  d4  00001fff00000000  d5  3fe999999999999a
05-06 15:59:44.911: I/DEBUG(3344):  d6  3ff0000000000000  d7  3eaaaaab3f800000
05-06 15:59:44.911: I/DEBUG(3344):  d8  0000000000000000  d9  0000000000000000
05-06 15:59:44.911: I/DEBUG(3344):  d10 0000000000000000  d11 0000000000000000
05-06 15:59:44.911: I/DEBUG(3344):  d12 0000000000000000  d13 0000000000000000
05-06 15:59:44.911: I/DEBUG(3344):  d14 0000000000000000  d15 0000000000000000
05-06 15:59:44.911: I/DEBUG(3344):  scr 80000012
05-06 15:59:45.011: I/DEBUG(3344):          #00  pc 00017880  /system/lib/libc.so
05-06 15:59:45.011: I/DEBUG(3344):          #01  pc 00007d8e  /system/lib/libcutils.so (mspace_free)
05-06 15:59:45.011: I/DEBUG(3344):          #02  pc 0007b746  /system/lib/libdvm.so (_Z21dvmHeapSourceFreeListjPPv)
05-06 15:59:45.011: I/DEBUG(3344):          #03  pc 00042f88  /system/lib/libdvm.so
05-06 15:59:45.011: I/DEBUG(3344):          #04  pc 00032fc8  /system/lib/libdvm.so (_Z22dvmHeapBitmapSweepWalkPK10HeapBitmapS1_jjPFvjPPvS2_ES2_)
05-06 15:59:45.011: I/DEBUG(3344):          #05  pc 00042f44  /system/lib/libdvm.so (_Z27dvmHeapSweepUnmarkedObjectsbbPjS_)
05-06 15:59:45.011: I/DEBUG(3344):          #06  pc 000336ac  /system/lib/libdvm.so (_Z25dvmCollectGarbageInternalPK6GcSpec)
05-06 15:59:45.011: I/DEBUG(3344):          #07  pc 0007bc1c  /system/lib/libdvm.so
05-06 15:59:45.011: I/DEBUG(3344):          #08  pc 0005f906  /system/lib/libdvm.so
05-06 15:59:45.011: I/DEBUG(3344):          #09  pc 00012e04  /system/lib/libc.so (__thread_entry)
05-06 15:59:45.011: I/DEBUG(3344):          #10  pc 00012958  /system/lib/libc.so (pthread_create)
05-06 15:59:45.011: I/DEBUG(3344): code around pc:
05-06 15:59:45.011: I/DEBUG(3344): 4006d860 4623b15c 2c006824 e026d1fb b12368db  .#F$h.,..&..h#.
05-06 15:59:45.011: I/DEBUG(3344): 4006d870 21014a17 6011447a 48124798 24002527  .J.!zD.`.G.H'%.$
05-06 15:59:45.011: I/DEBUG(3344): 4006d880 f7f47005 2106ee60 eeeef7f5 460aa901  .p..`..!.......F
05-06 15:59:45.011: I/DEBUG(3344): 4006d890 f04f2006 94015380 94029303 eab8f7f5  . O..S..........
05-06 15:59:45.011: I/DEBUG(3344): 4006d8a0 4622a905 f7f52002 f7f4eac2 2106ee4c  .."F. ......L..!
05-06 15:59:45.011: I/DEBUG(3344): code around lr:
05-06 15:59:45.011: I/DEBUG(3344): 40071100 41f0e92d 46804c0c 447c2600 68a56824  -..A.L.F.&|D$h.h
05-06 15:59:45.011: I/DEBUG(3344): 40071110 e0076867 300cf9b5 dd022b00 47c04628  gh.....0.+..(F.G
05-06 15:59:45.011: I/DEBUG(3344): 40071120 35544306 37fff117 6824d5f4 d1ee2c00  .CT5...7..$h.,..
05-06 15:59:45.011: I/DEBUG(3344): 40071130 e8bd4630 bf0081f0 000283da 41f0e92d  0F..........-..A
05-06 15:59:45.011: I/DEBUG(3344): 40071140 fb01b086 9004f602 461f4815 4615460c  .........H.F.F.F
05-06 15:59:45.011: I/DEBUG(3344): memory map around addr deadbaad:
05-06 15:59:45.011: I/DEBUG(3344): be97c000-be99d000 [stack]
05-06 15:59:45.011: I/DEBUG(3344): (no map for address)
05-06 15:59:45.011: I/DEBUG(3344): ffff0000-ffff1000 [vectors]
05-06 15:59:45.011: I/DEBUG(3344): stack:
05-06 15:59:45.011: I/DEBUG(3344):     100ffb10  4009965c  /system/lib/libc.so
05-06 15:59:45.011: I/DEBUG(3344):     100ffb14  00d9c060  [heap]
05-06 15:59:45.011: I/DEBUG(3344):     100ffb18  00000a96  
05-06 15:59:45.011: I/DEBUG(3344):     100ffb1c  4006fecd  /system/lib/libc.so
05-06 15:59:45.011: I/DEBUG(3344):     100ffb20  4009970c  /system/lib/libc.so
05-06 15:59:45.011: I/DEBUG(3344):     100ffb24  4009e85c  
05-06 15:59:45.011: I/DEBUG(3344):     100ffb28  00000000  
05-06 15:59:45.011: I/DEBUG(3344):     100ffb2c  40071121  /system/lib/libc.so
05-06 15:59:45.011: I/DEBUG(3344):     100ffb30  00000000  
05-06 15:59:45.011: I/DEBUG(3344):     100ffb34  100ffb64  
05-06 15:59:45.011: I/DEBUG(3344):     100ffb38  415bf010  /dev/ashmem/dalvik-heap (deleted)
05-06 15:59:45.011: I/DEBUG(3344):     100ffb3c  00000062  
05-06 15:59:45.011: I/DEBUG(3344):     100ffb40  415bf018  /dev/ashmem/dalvik-heap (deleted)
05-06 15:59:45.011: I/DEBUG(3344):     100ffb44  4007028d  /system/lib/libc.so
05-06 15:59:45.011: I/DEBUG(3344):     100ffb48  df0027ad  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb4c  00000000  
05-06 15:59:45.021: I/DEBUG(3344): #00 100ffb50  00000000  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb54  00000000  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb58  00000000  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb5c  00000000  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb60  00cf2780  [heap]
05-06 15:59:45.021: I/DEBUG(3344):     100ffb64  fffffbdf  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb68  00000020  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb6c  00000020  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb70  00000000  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb74  40018d91  /system/lib/libcutils.so
05-06 15:59:45.021: I/DEBUG(3344): #01 100ffb78  00cf2780  [heap]
05-06 15:59:45.021: I/DEBUG(3344):     100ffb7c  4162fe00  /dev/ashmem/dalvik-heap (deleted)
05-06 15:59:45.021: I/DEBUG(3344):     100ffb80  100ffcf4  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb84  00000062  
05-06 15:59:45.021: I/DEBUG(3344):     100ffb88  415bf018  /dev/ashmem/dalvik-heap (deleted)
05-06 15:59:45.021: I/DEBUG(3344):     100ffb8c  40800749  /system/lib/libdvm.so
05-06 15:59:45.661: I/BootReceiver(1265): Copying /data/tombstones/tombstone_01 to DropBox (SYSTEM_TOMBSTONE)
05-06 15:59:45.671: I/DEBUG(3344): debuggerd committing suicide to free the zombie!
05-06 15:59:45.671: I/DEBUG(3440): debuggerd: Apr 28 2013 11:10:17
05-06 15:59:45.681: D/Zygote(917): Process 3347 terminated by signal (11)
05-06 15:59:45.681: I/ActivityManager(1265): haveBgApp:true app.setAdj:10
05-06 15:59:45.681: I/ActivityManager(1265): Process com.nef.xxx (pid 3347) has died.
05-06 15:59:45.681: W/ActivityManager(1265): Scheduling restart of crashed service  com.nef.xxx/.service.renderService in 5000ms
05-06 15:59:48.241: D/PowerManagerService(1265): Screen must keep ON all the time! TimeoutTask return.
05-06 15:59:50.691: D/dalvikvm(3441): Late-enabling CheckJNI
05-06 15:59:50.701: I/ActivityManager(1265): Start proc com.nef.xxx for service com.nef.xxx/.service.renderService: pid=3441 uid=10009 gids={1015, 3003}
05-06 15:59:50.721: I/dalvikvm(3441): Turning on JNI app bug workarounds for target SDK version 9...

这个错误并不是再调用某个jni接口的时候发生的

而是反复调用之后（或是上层进行了一些其他操作后）冷不丁的蹦出来

程序虽然没有弹框，但进程已经挂了

这种随机问题最难搞了，很难确定哪行代码出的问题

于是各种百度谷歌寻求解决方案

其中最重要的错误信息是 Fatal signal 11 (SIGSEGV) at 0xdeadbaad (code=1)

网上也有很多人都遇到类似的问题

主要症结还是内存操作的问题

在经过各种排查测试后，折腾了老半天

终于找到问题所在，的确是内存操作有误

在jni里，我想把jbyteArray转化成char*

于是写了个转化函数，原型如下：

<span style="font-size:14px;">char* ConvertJByteaArrayToChars(JNIEnv *env, jbyteArray bytearray,  jbyte *&bytes)
{
    char *chars = NULL;
    bytes = env->GetByteArrayElements(bytearray, 0);
    chars = (char *)bytes;
    int chars_len = env->GetArrayLength(bytearray);
    chars[chars_len] = 0;
    return chars;


}</span>

问题就出在

<span style="font-size: 14px; color: rgb(255, 0, 0); ">chars[chars_len] = 0;</span>

这句话

假如GetByteArrayElements返回的是abc

则chars_len值为3

而chars[3]=0就等于是数组越界访问修改了

这样无形当中就破坏了堆内存给程序留下安全隐患

到特定时候就会触发错误爆发

后函数改为：

<span style="font-size:14px;">char* ConvertJByteaArrayToChars(JNIEnv *env, jbyteArray bytearray,  jbyte *&bytes)
{
    char *chars = NULL;
    bytes = env->GetByteArrayElements(bytearray, 0);
    int chars_len = env->GetArrayLength(bytearray);
    chars = new char[chars_len + 1];
    memcpy(chars, bytes, chars_len);
    chars[chars_len] = 0;
    return chars;
}</span>

就没有问题了

在调用函数处处理了char*之后再delete掉就ok了

哎，C++的指针真是让人又爱又恨

以后大家遇到类似问题

还是好好检查下native代码

看看有没有指针操作不当的问题

指针有风险，操作需谨慎

仅以此文小记，希望对大家有帮助~