{"id":42893,"date":"2025-06-10T08:57:27","date_gmt":"2025-06-10T00:57:27","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/42893.html"},"modified":"2025-06-10T08:57:27","modified_gmt":"2025-06-10T00:57:27","slug":"%e5%93%88%e5%b7%a5%e5%a4%a7%e8%ae%a1%e7%bb%9f%e5%a4%a7%e4%bd%9c%e4%b8%9a-%e7%a8%8b%e5%ba%8f%e4%ba%ba%e7%94%9f","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/42893.html","title":{"rendered":"\u54c8\u5de5\u5927\u8ba1\u7edf\u5927\u4f5c\u4e1a-\u7a0b\u5e8f\u4eba\u751f"},"content":{"rendered":"

\n

\u6458\u00a0 \u8981<\/p>\n

\u672c\u9879\u76ee\u4ee5\u201c\u7a0b\u5e8f\u4eba\u751f-Hello's P2P\u201d\u4e3a\u6838\u5fc3，\u901a\u8fc7\u7f16\u5199\u3001\u9884\u5904\u7406\u3001\u7f16\u8bd1\u3001\u6c47\u7f16\u3001\u94fe\u63a5\u53ca\u8fd0\u884c\u4e00\u4e2a\u7b80\u5355\u7684Hello\u7a0b\u5e8f，\u7cfb\u7edf\u63a2\u8ba8\u4e86\u8ba1\u7b97\u673a\u7cfb\u7edf\u4e2d\u7a0b\u5e8f\u4ece\u4ee3\u7801\u5230\u8fdb\u7a0b\u7684\u5168\u751f\u547d\u5468\u671f\u3002\u5b9e\u9a8c\u57fa\u4e8eUbuntu\u73af\u5883，\u4f7f\u7528GCC\u5de5\u5177\u94fe\u5b8c\u6210\u4ee3\u7801\u8f6c\u6362，\u5206\u6790\u4e86\u9884\u5904\u7406\u5c55\u5f00\u5934\u6587\u4ef6\u3001\u7f16\u8bd1\u751f\u6210\u6c47\u7f16\u6307\u4ee4\u3001\u6c47\u7f16\u751f\u6210\u53ef\u91cd\u5b9a\u4f4d\u76ee\u6807\u6587\u4ef6\u3001\u94fe\u63a5\u751f\u6210\u53ef\u6267\u884c\u6587\u4ef6\u7b49\u5173\u952e\u6b65\u9aa4\u7684\u5e95\u5c42\u673a\u5236\u3002\u7ed3\u5408\u8fdb\u7a0b\u7ba1\u7406\u3001\u5b58\u50a8\u7ba1\u7406\u548cIO\u7ba1\u7406，\u6df1\u5165\u63ed\u793a\u4e86\u64cd\u4f5c\u7cfb\u7edf\u5bf9\u7a0b\u5e8f\u6267\u884c\u7684\u8d44\u6e90\u5206\u914d\u3001\u5730\u5740\u8f6c\u6362\u3001\u5f02\u5e38\u5904\u7406\u53ca\u52a8\u6001\u94fe\u63a5\u7684\u652f\u6301\u3002\u9879\u76ee\u901a\u8fc7\u7406\u8bba\u4e0e\u5b9e\u8df5\u7ed3\u5408，\u5b8c\u6574\u5448\u73b0\u4e86\u7a0b\u5e8f\u5728\u7f16\u8bd1\u7cfb\u7edf\u3001\u64cd\u4f5c\u7cfb\u7edf\u548c\u786c\u4ef6\u534f\u540c\u4e0b\u7684\u8fd0\u884c\u6d41\u7a0b，\u9a8c\u8bc1\u4e86\u8ba1\u7b97\u673a\u7cfb\u7edf\u5206\u5c42\u62bd\u8c61\u4e0e\u6a21\u5757\u5316\u8bbe\u8ba1\u7684\u9ad8\u6548\u6027，\u4e3a\u6df1\u5165\u7406\u89e3\u7cfb\u7edf\u7ea7\u7f16\u7a0b\u4e0e\u4f18\u5316\u63d0\u4f9b\u4e86\u91cd\u8981\u53c2\u8003\u3002<\/p>\n

\n

\u5173\u952e\u8bcd：\u9884\u5904\u7406；\u7f16\u8bd1；\u94fe\u63a5；\u8fdb\u7a0b\u7ba1\u7406；\u5b58\u50a8\u7ba1\u7406；\u52a8\u6001\u94fe\u63a5；IO\u7ba1\u7406\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0<\/p>\n

\n

\u76ee\u00a0 \u5f55<\/p>\n

\n

\u7b2c1\u7ae0 \u6982\u8ff0………………………………………………………………………………………………. – 4 –<\/p>\n

1.1 Hello\u7b80\u4ecb………………………………………………………………………………………… – 4 –<\/p>\n

1.2 \u73af\u5883\u4e0e\u5de5\u5177……………………………………………………………………………………….. – 4 –<\/p>\n

1.3 \u4e2d\u95f4\u7ed3\u679c…………………………………………………………………………………………… – 4 –<\/p>\n

1.4 \u672c\u7ae0\u5c0f\u7ed3…………………………………………………………………………………………… – 4 –<\/p>\n

\u7b2c2\u7ae0 \u9884\u5904\u7406…………………………………………………………………………………………… – 5 –<\/p>\n

2.1 \u9884\u5904\u7406\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528…………………………………………………………………………. – 5 –<\/p>\n

2.2\u5728Ubuntu\u4e0b\u9884\u5904\u7406\u7684\u547d\u4ee4……………………………………………………………….. – 5 –<\/p>\n

2.3 Hello\u7684\u9884\u5904\u7406\u7ed3\u679c\u89e3\u6790…………………………………………………………………… – 5 –<\/p>\n

2.4 \u672c\u7ae0\u5c0f\u7ed3…………………………………………………………………………………………… – 5 –<\/p>\n

\u7b2c3\u7ae0 \u7f16\u8bd1………………………………………………………………………………………………. – 6 –<\/p>\n

3.1 \u7f16\u8bd1\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528…………………………………………………………………………….. – 6 –<\/p>\n

3.2 \u5728Ubuntu\u4e0b\u7f16\u8bd1\u7684\u547d\u4ee4………………………………………………………………….. – 6 –<\/p>\n

3.3 Hello\u7684\u7f16\u8bd1\u7ed3\u679c\u89e3\u6790………………………………………………………………………. – 6 –<\/p>\n

3.4 \u672c\u7ae0\u5c0f\u7ed3…………………………………………………………………………………………… – 6 –<\/p>\n

\u7b2c4\u7ae0 \u6c47\u7f16………………………………………………………………………………………………. – 7 –<\/p>\n

4.1 \u6c47\u7f16\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528…………………………………………………………………………….. – 7 –<\/p>\n

4.2 \u5728Ubuntu\u4e0b\u6c47\u7f16\u7684\u547d\u4ee4………………………………………………………………….. – 7 –<\/p>\n

4.3 \u53ef\u91cd\u5b9a\u4f4d\u76ee\u6807elf\u683c\u5f0f……………………………………………………………………… – 7 –<\/p>\n

4.4 Hello.o\u7684\u7ed3\u679c\u89e3\u6790………………………………………………………………………….. – 7 –<\/p>\n

4.5 \u672c\u7ae0\u5c0f\u7ed3…………………………………………………………………………………………… – 7 –<\/p>\n

\u7b2c5\u7ae0 \u94fe\u63a5………………………………………………………………………………………………. – 8 –<\/p>\n

5.1 \u94fe\u63a5\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528…………………………………………………………………………….. – 8 –<\/p>\n

5.2 \u5728Ubuntu\u4e0b\u94fe\u63a5\u7684\u547d\u4ee4………………………………………………………………….. – 8 –<\/p>\n

5.3 \u53ef\u6267\u884c\u76ee\u6807\u6587\u4ef6hello\u7684\u683c\u5f0f………………………………………………………….. – 8 –<\/p>\n

5.4 hello\u7684\u865a\u62df\u5730\u5740\u7a7a\u95f4………………………………………………………………………. – 8 –<\/p>\n

5.5 \u94fe\u63a5\u7684\u91cd\u5b9a\u4f4d\u8fc7\u7a0b\u5206\u6790……………………………………………………………………… – 8 –<\/p>\n

5.6 hello\u7684\u6267\u884c\u6d41\u7a0b……………………………………………………………………………… – 8 –<\/p>\n

5.7 Hello\u7684\u52a8\u6001\u94fe\u63a5\u5206\u6790………………………………………………………………………. – 8 –<\/p>\n

5.8 \u672c\u7ae0\u5c0f\u7ed3…………………………………………………………………………………………… – 9 –<\/p>\n

\u7b2c6\u7ae0 hello\u8fdb\u7a0b\u7ba1\u7406……………………………………………………………………….. – 10 –<\/p>\n

6.1 \u8fdb\u7a0b\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528…………………………………………………………………………… – 10 –<\/p>\n

6.2 \u7b80\u8ff0\u58f3Shell-bash\u7684\u4f5c\u7528\u4e0e\u5904\u7406\u6d41\u7a0b…………………………………………….. – 10 –<\/p>\n

6.3 Hello\u7684fork\u8fdb\u7a0b\u521b\u5efa\u8fc7\u7a0b…………………………………………………………… – 10 –<\/p>\n

6.4 Hello\u7684execve\u8fc7\u7a0b……………………………………………………………………… – 10 –<\/p>\n

6.5 Hello\u7684\u8fdb\u7a0b\u6267\u884c……………………………………………………………………………. – 10 –<\/p>\n

6.6 hello\u7684\u5f02\u5e38\u4e0e\u4fe1\u53f7\u5904\u7406…………………………………………………………………. – 10 –<\/p>\n

6.7\u672c\u7ae0\u5c0f\u7ed3…………………………………………………………………………………………. – 10 –<\/p>\n

\u7b2c7\u7ae0 hello\u7684\u5b58\u50a8\u7ba1\u7406…………………………………………………………………….. – 11 –<\/p>\n

7.1 hello\u7684\u5b58\u50a8\u5668\u5730\u5740\u7a7a\u95f4…………………………………………………………………. – 11 –<\/p>\n

7.2 Intel\u903b\u8f91\u5730\u5740\u5230\u7ebf\u6027\u5730\u5740\u7684\u53d8\u6362-\u6bb5\u5f0f\u7ba1\u7406…………………………………….. – 11 –<\/p>\n

7.3 Hello\u7684\u7ebf\u6027\u5730\u5740\u5230\u7269\u7406\u5730\u5740\u7684\u53d8\u6362-\u9875\u5f0f\u7ba1\u7406………………………………… – 11 –<\/p>\n

7.4 TLB\u4e0e\u56db\u7ea7\u9875\u8868\u652f\u6301\u4e0b\u7684VA\u5230PA\u7684\u53d8\u6362……………………………………… – 11 –<\/p>\n

7.5 \u4e09\u7ea7Cache\u652f\u6301\u4e0b\u7684\u7269\u7406\u5185\u5b58\u8bbf\u95ee…………………………………………………. – 11 –<\/p>\n

7.6 hello\u8fdb\u7a0bfork\u65f6\u7684\u5185\u5b58\u6620\u5c04………………………………………………………… – 11 –<\/p>\n

7.7 hello\u8fdb\u7a0bexecve\u65f6\u7684\u5185\u5b58\u6620\u5c04…………………………………………………….. – 11 –<\/p>\n

7.8 \u7f3a\u9875\u6545\u969c\u4e0e\u7f3a\u9875\u4e2d\u65ad\u5904\u7406………………………………………………………………… – 11 –<\/p>\n

7.9\u52a8\u6001\u5b58\u50a8\u5206\u914d\u7ba1\u7406…………………………………………………………………………… – 11 –<\/p>\n

7.10\u672c\u7ae0\u5c0f\u7ed3……………………………………………………………………………………….. – 12 –<\/p>\n

\u7b2c8\u7ae0 hello\u7684IO\u7ba1\u7406……………………………………………………………………… – 13 –<\/p>\n

8.1 Linux\u7684IO\u8bbe\u5907\u7ba1\u7406\u65b9\u6cd5……………………………………………………………….. – 13 –<\/p>\n

8.2 \u7b80\u8ff0Unix IO\u63a5\u53e3\u53ca\u5176\u51fd\u6570…………………………………………………………….. – 13 –<\/p>\n

8.3 printf\u7684\u5b9e\u73b0\u5206\u6790……………………………………………………………………………. – 13 –<\/p>\n

8.4 getchar\u7684\u5b9e\u73b0\u5206\u6790………………………………………………………………………… – 13 –<\/p>\n

8.5\u672c\u7ae0\u5c0f\u7ed3…………………………………………………………………………………………. – 13 –<\/p>\n

\u7ed3\u8bba…………………………………………………………………………………………………………. – 14 –<\/p>\n

\u9644\u4ef6…………………………………………………………………………………………………………. – 15 –<\/p>\n

\u53c2\u8003\u6587\u732e………………………………………………………………………………………………….. – 16 –<\/p>\n

\n

\n<\/p>\n

\u7b2c1\u7ae0 \u6982\u8ff0<\/h2>\n

1.1 Hello\u7b80\u4ecb<\/h3>\n

Program：\u5728VSCode\u4e2d\u7f16\u5199hello.c<\/p>\n

\u9884\u5904\u7406：gcc -E hello.c -o hello.i \u2192 \u5c55\u5f00\u5934\u6587\u4ef6<\/p>\n

\u7f16\u8bd1：gcc -S hello.i -o hello.s \u2192 \u751f\u6210x86_64\u6c47\u7f16<\/p>\n

\u6c47\u7f16：gcc -c hello.s -o hello.o \u2192 \u751f\u6210ELF\u53ef\u91cd\u5b9a\u4f4d\u6587\u4ef6<\/p>\n

\u94fe\u63a5：gcc hello.o -o hello \u2192 \u52a8\u6001\u94fe\u63a5glibc 2.38<\/p>\n

Process：Shell\u901a\u8fc7fork()\u521b\u5efa\u5b50\u8fdb\u7a0b，execve()\u52a0\u8f7dhello\u3002<\/p>\n

OS\u5206\u914d\u865a\u62df\u5185\u5b58，CPU\u6267\u884c\u6307\u4ee4\u540e\u8c03\u7528exit_group(0)\u7ec8\u6b62\u3002<\/p>\n

020（From Zero to Zero）：0\u21921：\u6587\u672c\u6587\u4ef6\u2192\u53ef\u6267\u884c\u6587\u4ef6<\/p>\n

1\u21920：\u8fdb\u7a0b\u7ec8\u6b62\u540e，OS\u56de\u6536\u9875\u8868\u3001\u6587\u4ef6\u63cf\u8ff0\u7b26\u7b49\u8d44\u6e90\u3002<\/p>\n

1.2 \u73af\u5883\u4e0e\u5de5\u5177<\/h3>\n

\u786c\u4ef6\u00a0\u00a0\u00a0\u00a0 x86_64 CPU, DELL\u670d\u52a1\u5668(Ubuntu)<\/p>\n

\u5185\u6838\u00a0\u00a0\u00a0\u00a0 Linux 6.8.0-54-generic<\/p>\n

\u5de5\u5177\u94fe GCC 13.3.0（-Og）\u3001GNU Binutils 2.41\u3001glibc 2.38<\/p>\n

\u8c03\u8bd5\u00a0\u00a0\u00a0\u00a0 GDB 14.2\u3001strace 6.8\u3001objdump 2.41<\/p>\n

\u7f16\u8f91\u5668 VSCode<\/p>\n

1.3 \u4e2d\u95f4\u7ed3\u679c<\/h3>\n

hello.i\u00a0\u00a0\u00a0\u00a0 # \u9884\u5904\u7406\u540e\u4ee3\u7801<\/p>\n

hello.s\u00a0\u00a0\u00a0\u00a0 # \u6c47\u7f16\u4ee3\u7801<\/p>\n

hello.o\u00a0\u00a0\u00a0\u00a0 # ELF\u6587\u4ef6<\/p>\n

hello\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # \u52a8\u6001\u94fe\u63a5\u53ef\u6267\u884c\u6587\u4ef6<\/p>\n

1.4 \u672c\u7ae0\u5c0f\u7ed3<\/h3>\n

\u672c\u7ae0\u7b80\u8ff0\u4e86Hello\u7a0b\u5e8f\u7684P2P（\u4ece\u4ee3\u7801\u5230\u8fdb\u7a0b）\u548c020（\u4ece\u65e0\u5230\u65e0）\u751f\u547d\u5468\u671f，\u5217\u51fa\u4e86\u5b9e\u9a8c\u73af\u5883\u548c\u751f\u6210\u7684\u4e2d\u95f4\u6587\u4ef6\u3002\u540e\u7eed\u7ae0\u8282\u5c06\u6df1\u5165\u5206\u6790\u9884\u5904\u7406\u3001\u7f16\u8bd1\u3001\u8fdb\u7a0b\u8fd0\u884c\u7b49\u7ec6\u8282\u3002<\/p>\n<\/p>\n

\u7b2c2\u7ae0 \u9884\u5904\u7406<\/h2>\n

2.1 \u9884\u5904\u7406\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528<\/h3>\n

\u9884\u5904\u7406（Preprocessing）\u662fC\u7a0b\u5e8f\u7f16\u8bd1\u7684\u7b2c\u4e00\u6b65，\u7531\u9884\u5904\u7406\u5668（cpp）\u6267\u884c，\u4e3b\u8981\u5b8c\u6210\u4ee5\u4e0b\u4efb\u52a1：<\/p>\n

\u5b8f\u5c55\u5f00：\u66ff\u6362#define\u5b9a\u4e49\u7684\u5b8f<\/p>\n

\u5934\u6587\u4ef6\u5305\u542b：\u9012\u5f52\u5c55\u5f00#include\u6307\u4ee4，\u63d2\u5165\u5934\u6587\u4ef6\u5185\u5bb9<\/p>\n

\u6761\u4ef6\u7f16\u8bd1：\u5904\u7406#if\u3001#ifdef\u7b49\u6307\u4ee4，\u51b3\u5b9a\u662f\u5426\u5305\u542b\u4ee3\u7801\u5757<\/p>\n

\u5220\u9664\u6ce8\u91ca：\u79fb\u9664\u6240\u6709\/* … *\/\u548c\/\/\u6ce8\u91ca<\/p>\n

\u6dfb\u52a0\u884c\u6807\u8bb0：\u63d2\u5165#line\u6307\u4ee4，\u4fbf\u4e8e\u8c03\u8bd5\u65f6\u5b9a\u4f4d\u6e90\u7801\u4f4d\u7f6e\u3002<\/p>\n

\u4f5c\u7528：<\/p>\n

\u4f7f\u4ee3\u7801\u53ef\u79fb\u690d（\u5982\u901a\u8fc7\u6761\u4ef6\u7f16\u8bd1\u9002\u914d\u4e0d\u540c\u5e73\u53f0）<\/p>\n

\u51cf\u5c11\u91cd\u590d\u4ee3\u7801（\u901a\u8fc7\u5934\u6587\u4ef6\u548c\u5b8f）<\/p>\n

\u751f\u6210\u201c\u7eaf\u51c0\u201d\u7684C\u4ee3\u7801（\u4e0d\u542b\u9884\u5904\u7406\u6307\u4ee4），\u4f9b\u7f16\u8bd1\u5668\u5904\u7406<\/p>\n

2.2\u5728Ubuntu\u4e0b\u9884\u5904\u7406\u7684\u547d\u4ee4<\/h3>\n

\"\"<\/p>\n

-m64：64\u4f4d\u00a0\u00a0 -E：\u4ec5\u9884\u5904\u7406\u00a0 -o hello.i：\u8f93\u51fa\u5230hello.i\u6587\u4ef6\u3002<\/p>\n

2.3 Hello\u7684\u9884\u5904\u7406\u7ed3\u679c\u89e3\u6790<\/h3>\n

\u5934\u6587\u4ef6\u5c55\u5f00：<\/p>\n

\u539f\u59cb\u4ee3\u7801\u4e2d\u7684#include\u88ab\u66ff\u6362\u4e3a\u5934\u6587\u4ef6\u5185\u5bb9：<\/p>\n

stdio.h：\u63d2\u5165printf\u3001exit\u7b49\u51fd\u6570\u58f0\u660e<\/p>\n

unistd.h：\u63d2\u5165sleep\u3001getchar\u7b49\u7cfb\u7edf\u8c03\u7528\u58f0\u660e<\/p>\n

stdlib.h：\u63d2\u5165atoi\u7684\u51fd\u6570\u58f0\u660e<\/p>\n

\u6ce8\u91ca\u5220\u9664：<\/p>\n

\u6e90\u7801\u5f00\u5934\u7684\u6ce8\u91ca\u88ab\u5b8c\u5168\u79fb\u9664<\/p>\n

\u884c\u6807\u8bb0：<\/p>\n

\u63d2\u5165#line\u6307\u4ee4，\u6807\u8bc6\u539f\u59cb\u4ee3\u7801\u4f4d\u7f6e<\/p>\n

2.4 \u672c\u7ae0\u5c0f\u7ed3<\/h3>\n

\u672c\u7ae0\u901a\u8fc7gcc -E\u547d\u4ee4\u5bf9hello.c\u8fdb\u884c\u9884\u5904\u7406，\u751f\u6210hello.i\u6587\u4ef6，\u5e76\u5206\u6790\u5176\u5185\u5bb9，\u8fdb\u884c\u9884\u5904\u7406\u6838\u5fc3\u4efb\u52a1：\u5934\u6587\u4ef6\u5c55\u5f00（\u63d2\u5165stdio.h\u7b49）\u3001\u5220\u9664\u6ce8\u91ca\u3001\u6dfb\u52a0\u884c\u6807\u8bb0\u3002\u539f\u59cb\u4ee3\u7801\u4ece24\u884c\u6269\u5c55\u4e3a3180\u884c（\u4e3b\u8981\u56e0\u5934\u6587\u4ef6\u63d2\u5165）,\u4fdd\u7559\u4e86\u6240\u6709\u51fd\u6570\u8c03\u7528（printf\u3001sleep）\u7684\u58f0\u660e\u3002<\/p>\n<\/p>\n

\u7b2c3\u7ae0 \u7f16\u8bd1<\/h2>\n

3.1 \u7f16\u8bd1\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528<\/h3>\n

\u6982\u5ff5：<\/p>\n

\u7f16\u8bd1（Compilation）\u6307\u5c06\u9884\u5904\u7406\u540e\u7684C\u4ee3\u7801（.i）\u8f6c\u6362\u4e3a\u6c47\u7f16\u4ee3\u7801（.s）\u7684\u8fc7\u7a0b，\u7531\u7f16\u8bd1\u5668（GCC\u7684cc1\u7ec4\u4ef6）\u5b8c\u6210<\/p>\n

\u4f5c\u7528：<\/p>\n

\u8bed\u6cd5\u5206\u6790：\u68c0\u67e5\u4ee3\u7801\u662f\u5426\u7b26\u5408C\u8bed\u8a00\u89c4\u8303<\/p>\n

\u8bed\u4e49\u4f18\u5316：\u5728-Og\u4f18\u5316\u7ea7\u522b\u4e0b，\u5e73\u8861\u53ef\u8bfb\u6027\u4e0e\u6027\u80fd<\/p>\n

\u751f\u6210\u6c47\u7f16：\u5c06\u9ad8\u7ea7C\u4ee3\u7801\u8f6c\u6362\u4e3a\u4f4e\u7ea7\u673a\u5668\u6307\u4ee4\u7684\u52a9\u8bb0\u7b26<\/p>\n

3.2 \u5728Ubuntu\u4e0b\u7f16\u8bd1\u7684\u547d\u4ee4<\/h3>\n

\"\"<\/p>\n

-m64：64\u4f4d\u00a0\u00a0 -S：\u751f\u6210\u6c47\u7f16\u4ee3\u7801\u00a0 -Og：\u542f\u7528\u8c03\u8bd5\u4f18\u5316<\/p>\n

3.3 Hello\u7684\u7f16\u8bd1\u7ed3\u679c\u89e3\u6790<\/h3>\n

3.3.1 \u5b57\u7b26\u4e32\u5904\u7406<\/p>\n

.LC0:<\/p>\n

\u00a0\u00a0\u00a0 .string "\\\\347\\\\224\\\\250\\\\346\\\\263\\\\225…"\u00a0 # UTF-8\u7f16\u7801\u7684\u4e2d\u6587\u5b57\u7b26\u4e32<\/p>\n

.LC1:<\/p>\n

\u00a0\u00a0\u00a0 .string "Hello %s %s %s\\\\n"\u00a0 # printf\u683c\u5f0f\u5b57\u7b26\u4e32<\/p>\n

3.3.2 \u51fd\u6570\u6846\u67b6<\/p>\n

\u51fd\u6570\u5165\u53e3：<\/p>\n

main:<\/p>\n

\u00a0\u00a0\u00a0 endbr64\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # \u5bf9\u6297ROP\u653b\u51fb\u7684\u6307\u4ee4<\/p>\n

\u00a0\u00a0\u00a0 pushq %rbp\u00a0\u00a0\u00a0\u00a0 # \u4fdd\u5b58\u57fa\u5740\u6307\u9488<\/p>\n

\u00a0\u00a0\u00a0 pushq %rbx\u00a0\u00a0\u00a0\u00a0 # \u4fdd\u5b58\u88ab\u8c03\u7528\u8005\u4fdd\u5b58\u5bc4\u5b58\u5668<\/p>\n

\u00a0\u00a0\u00a0 subq $8, %rsp\u00a0 # \u5206\u914d\u6808\u7a7a\u95f4<\/p>\n

3.3.3 \u53c2\u6570\u68c0\u67e5<\/p>\n

cmpl $5, %edi\u00a0\u00a0\u00a0\u00a0 # \u6bd4\u8f83argc\u548c5<\/p>\n

jne .L6\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # \u4e0d\u7b49\u4e8e\u5219\u8df3\u8f6c\u9519\u8bef\u5904\u7406<\/p>\n

movq %rsi, %rbx\u00a0\u00a0 # \u4fdd\u5b58argv\u6307\u9488<\/p>\n

3.3.4 \u9519\u8bef\u5904\u7406<\/p>\n

.L6:<\/p>\n

\u00a0\u00a0\u00a0 leaq .LC0(%rip), %rdi\u00a0 # \u52a0\u8f7d\u9519\u8bef\u5b57\u7b26\u4e32\u5730\u5740<\/p>\n

\u00a0\u00a0\u00a0 call puts@PLT\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # \u8c03\u7528puts\u8f93\u51fa<\/p>\n

\u00a0\u00a0\u00a0 movl $1, %edi<\/p>\n

\u00a0\u00a0\u00a0 call exit@PLT\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # \u9000\u51fa\u7a0b\u5e8f<\/p>\n

3.3.5 \u4e3b\u5faa\u73af\u7ed3\u6784<\/p>\n

\u5faa\u73af\u521d\u59cb\u5316：movl $0, %ebp\u00a0 # i = 0<\/p>\n

\u5faa\u73af\u6761\u4ef6：<\/p>\n

.L2:<\/p>\n

\u00a0\u00a0\u00a0 cmpl $9, %ebp\u00a0\u00a0 # \u6bd4\u8f83i\u548c9<\/p>\n

\u00a0\u00a0\u00a0 jle .L3\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # i <= 9\u65f6\u7ee7\u7eed\u5faa\u73af<\/p>\n

\u5faa\u73af\u589e\u91cf：addl $1, %ebp\u00a0 # i++<\/p>\n

3.3.6 \u51fd\u6570\u8c03\u7528<\/p>\n

printf\u8c03\u7528：<\/p>\n

movq 24(%rbx), %rcx\u00a0 # argv[3]<\/p>\n

movq 16(%rbx), %rdx\u00a0 # argv[2]<\/p>\n

movq 8(%rbx), %rsi\u00a0\u00a0\u00a0 # argv[1]<\/p>\n

leaq .LC1(%rip), %rdi # \u683c\u5f0f\u5b57\u7b26\u4e32<\/p>\n

movl $0, %eax\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # \u6e05\u7a7a\u6d6e\u70b9\u5bc4\u5b58\u5668<\/p>\n

call printf@PLT<\/p>\n

\u5176\u4ed6\u8c03\u7528：<\/p>\n

call atoi@PLT\u00a0\u00a0\u00a0 # \u5b57\u7b26\u4e32\u8f6c\u6574\u6570<\/p>\n

call sleep@PLT\u00a0\u00a0 # \u5ef6\u65f6<\/p>\n

call getchar@PLT # \u7b49\u5f85\u8f93\u5165<\/p>\n

3.3.7 \u51fd\u6570\u8fd4\u56de<\/p>\n

movl $0, %eax\u00a0 # \u8fd4\u56de\u503c0<\/p>\n

addq $8, %rsp\u00a0 # \u91ca\u653e\u6808\u7a7a\u95f4<\/p>\n

popq %rbx\u00a0\u00a0\u00a0\u00a0\u00a0 # \u6062\u590d\u5bc4\u5b58\u5668<\/p>\n

popq %rbp<\/p>\n

ret<\/p>\n

3.4 \u672c\u7ae0\u5c0f\u7ed3<\/h3>\n

\u7f16\u8bd1\u5668\u5c06C\u4ee3\u7801\u51c6\u786e\u8f6c\u6362\u4e3ax86_64\u6c47\u7f16\u6307\u4ee4,\u4f18\u5316\u9009\u9879-Og\u4fdd\u6301\u4e86\u4ee3\u7801\u53ef\u8bfb\u6027,\u5b8c\u6574\u5b9e\u73b0\u4e86：\u53c2\u6570\u68c0\u67e5\u3001\u5faa\u73af\u63a7\u5236\u3001\u591a\u53c2\u6570\u51fd\u6570\u8c03\u7528\u3001\u7cfb\u7edf\u8c03\u7528\u3002\u7b26\u5408x86_64\u8c03\u7528\u7ea6\u5b9a\u3002<\/p>\n

\u4f7f\u7528RIP\u76f8\u5bf9\u5bfb\u5740\u8bbf\u95ee\u5b57\u7b26\u4e32\u5e38\u91cf，\u53c2\u6570\u901a\u8fc7\u5bc4\u5b58\u5668\u4f20\u9012（rdi, rsi, rdx, rcx），\u5faa\u73af\u8f6c\u6362\u4e3a\u6761\u4ef6\u8df3\u8f6c\u7ed3\u6784，\u5b8c\u6574\u4fdd\u7559\u4e86\u7a0b\u5e8f\u7684\u63a7\u5236\u6d41\u903b\u8f91\u3002<\/p>\n<\/p>\n

\u7b2c4\u7ae0 \u6c47\u7f16<\/h2>\n

4.1 \u6c47\u7f16\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528<\/h3>\n

\u6982\u5ff5：<\/p>\n

\u6c47\u7f16\u662f\u5c06\u6c47\u7f16\u4ee3\u7801（.s）\u8f6c\u6362\u4e3a\u673a\u5668\u8bed\u8a00\u4e8c\u8fdb\u5236\u76ee\u6807\u6587\u4ef6（.o）\u7684\u8fc7\u7a0b，\u7531\u6c47\u7f16\u5668\u5b8c\u6210<\/p>\n

\u4f5c\u7528：<\/p>\n

\u6307\u4ee4\u7f16\u7801：\u5c06\u6c47\u7f16\u52a9\u8bb0\u7b26\u8f6c\u6362\u4e3a\u673a\u5668\u7801<\/p>\n

\u751f\u6210\u53ef\u91cd\u5b9a\u4f4d\u76ee\u6807\u6587\u4ef6：\u5305\u542b\u4ee3\u7801\u3001\u6570\u636e\u3001\u7b26\u53f7\u8868\u548c\u91cd\u5b9a\u4f4d\u4fe1\u606f，\u4f9b\u94fe\u63a5\u5668\u4f7f\u7528<\/p>\n

4.2 \u5728Ubuntu\u4e0b\u6c47\u7f16\u7684\u547d\u4ee4<\/h3>\n

\"\"<\/p>\n

-c：\u4ec5\u6c47\u7f16\u4e0d\u94fe\u63a5\u00a0\u00a0 -m64：\u751f\u621064\u4f4d\u76ee\u6807\u6587\u4ef6<\/p>\n

4.3 \u53ef\u91cd\u5b9a\u4f4d\u76ee\u6807elf\u683c\u5f0f<\/h3>\n

4.3.1 \u8282\u5934\u57fa\u672c\u4fe1\u606f<\/p>\n

\u901a\u8fc7 readelf -S hello.o \u5206\u6790\u76ee\u6807\u6587\u4ef6\u7ed3\u6784：<\/p>\n

\"\"<\/p>\n\n\n\n\n\n\n\n\n\n
\n

\u8282\u540d<\/p>\n<\/td>\n

\n

\u7c7b\u578b<\/p>\n<\/td>\n

\n

\u5927\u5c0f<\/p>\n<\/td>\n

\n

\u6807\u5fd7<\/p>\n<\/td>\n

\n

\u8bf4\u660e<\/p>\n<\/td>\n<\/tr>\n

\n

.text<\/p>\n<\/td>\n

\n

PROGBITS<\/p>\n<\/td>\n

\n

0x75<\/p>\n<\/td>\n

\n

AX<\/p>\n<\/td>\n

\n

\u4e3b\u51fd\u6570\u673a\u5668\u6307\u4ee4（\u53ef\u6267\u884c\u4ee3\u7801）<\/p>\n<\/td>\n<\/tr>\n

\n

.rela.text<\/p>\n<\/td>\n

\n

RELA<\/p>\n<\/td>\n

\n

0xc0<\/p>\n<\/td>\n

\n

I<\/p>\n<\/td>\n

\n

.text\u8282\u7684\u91cd\u5b9a\u4f4d\u6761\u76ee（\u9700\u94fe\u63a5\u5668\u4fee\u6b63\u5730\u5740）<\/p>\n<\/td>\n<\/tr>\n

\n

.rodata.str1.8<\/p>\n<\/td>\n

\n

PROGBITS<\/p>\n<\/td>\n

\n

0x30<\/p>\n<\/td>\n

\n

AMS<\/p>\n<\/td>\n

\n

8\u5b57\u8282\u5bf9\u9f50\u7684\u53ea\u8bfb\u5b57\u7b26\u4e32（\u4e2d\u6587\u9519\u8bef\u63d0\u793a.LC0）<\/p>\n<\/td>\n<\/tr>\n

\n

.rodata.str1.1<\/p>\n<\/td>\n

\n

PROGBITS<\/p>\n<\/td>\n

\n

0x10<\/p>\n<\/td>\n

\n

AMS<\/p>\n<\/td>\n

\n

1\u5b57\u8282\u5bf9\u9f50\u7684\u53ea\u8bfb\u5b57\u7b26\u4e32（Hello\u683c\u5f0f\u4e32.LC1）<\/p>\n<\/td>\n<\/tr>\n

\n

.eh_frame<\/p>\n<\/td>\n

\n

PROGBITS<\/p>\n<\/td>\n

\n

0x40<\/p>\n<\/td>\n

\n

A<\/p>\n<\/td>\n

\n

\u5f02\u5e38\u5904\u7406\u5e27\u4fe1\u606f（\u7528\u4e8e\u6808\u5c55\u5f00）<\/p>\n<\/td>\n<\/tr>\n

\n

.symtab<\/p>\n<\/td>\n

\n

SYMTAB<\/p>\n<\/td>\n

\n

0x120<\/p>\n<\/td>\n

\n

–<\/p>\n<\/td>\n

\n

\u7b26\u53f7\u8868（\u51fd\u6570\u548c\u5168\u5c40\u53d8\u91cf\u540d）<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

4.3.2 \u91cd\u5b9a\u4f4d\u9879\u76ee\u5206\u6790<\/p>\n

\u901a\u8fc7 readelf -r hello.o \u67e5\u770b\u91cd\u5b9a\u4f4d\u6761\u76ee：<\/p>\n

\"\"<\/p>\n

R_X86_64_PC32（\u672c\u5730\u7b26\u53f7\u76f8\u5bf9\u5730\u5740\u4fee\u6b63）<\/p>\n

\u4f5c\u7528：\u52a0\u8f7d\u5b57\u7b26\u4e32\u5730\u5740（.LC0）<\/p>\n

\u6307\u4ee4：lea .LC0(%rip), %rdi<\/p>\n

\u516c\u5f0f：\u6700\u7ec8\u5730\u5740=Symbol\u5730\u5740\u2212Offset\u22124<\/p>\n

R_X86_64_PLT32（\u5916\u90e8\u51fd\u6570PLT\u8df3\u8f6c\u4fee\u6b63）<\/p>\n

\u4f5c\u7528：\u8c03\u7528\u52a8\u6001\u5e93\u51fd\u6570（printf\u3001sleep）<\/p>\n

\u6307\u4ee4：call printf@PLT<\/p>\n

\u516c\u5f0f：PLT\u504f\u79fb=PLT\u8868\u57fa\u5740+Symbol\u5728PLT\u4e2d\u7684\u7d22\u5f15\u00d716\u2212Offset\u22124<\/p>\n

4.4 Hello.o\u7684\u7ed3\u679c\u89e3\u6790<\/h3>\n

\u901a\u8fc7 objdump -d -r hello.o \u8f93\u51fa\u7684\u53cd\u6c47\u7f16\u7ed3\u679c，\u7ed3\u5408\u7b2c3\u7ae0\u7684 hello.s \u6c47\u7f16\u4ee3\u7801，\u5bf9 hello.o \u7684\u673a\u5668\u8bed\u8a00\u6784\u6210\u3001\u91cd\u5b9a\u4f4d\u6761\u76ee\u53ca\u4e0e\u6c47\u7f16\u7684\u6620\u5c04\u5173\u7cfb\u8fdb\u884c\u8be6\u7ec6\u5206\u6790\u3002<\/p>\n

4.4.1\u6c47\u7f16\u4e0e\u53cd\u6c47\u7f16\u7684\u5bf9\u6bd4\u5206\u6790<\/p>\n

4.4.1.1 \u51fd\u6570\u5165\u53e3\u4e0e\u6808\u5e27\u6784\u5efa<\/p>\n

\u6c47\u7f16\u4ee3\u7801（hello.s）：<\/p>\n

\"\"<\/p>\n

\u53cd\u6c47\u7f16（hello.o）：<\/p>\n

\n

\"\"<\/p>\n

\u5206\u6790：<\/p>\n

\u673a\u5668\u7801：f3 0f 1e fa：endbr64（Intel CET\u6307\u4ee4，\u9632\u5fa1ROP\u653b\u51fb）\u3002<\/p>\n

55 53 48 83 ec 08：\u4fdd\u5b58 %rbp\u3001%rbx，\u5206\u914d8\u5b57\u8282\u6808\u7a7a\u95f4\u3002<\/p>\n

\u64cd\u4f5c\u6570\u7f16\u7801：\u65e0\u91cd\u5b9a\u4f4d\u9700\u6c42，\u504f\u79fb\u91cf\u76f4\u63a5\u7f16\u7801（sub $0x8,%rsp \u5bf9\u5e94 48 83 ec 08）\u3002<\/p>\n

4.4.1.2 \u53c2\u6570\u68c0\u67e5\u4e0e\u9519\u8bef\u5904\u7406<\/p>\n

\u6c47\u7f16\u4ee3\u7801（hello.s）：<\/p>\n

\"\"<\/p>\n

\u53cd\u6c47\u7f16（hello.o）：<\/p>\n

\"\"\u5206\u6790：<\/p>\n

\u673a\u5668\u7801：83 ff 05：cmpl $5, %edi（\u6bd4\u8f83argc\u4e0e5）\u3002<\/p>\n

75 0a：jne（\u6761\u4ef6\u4e0d\u6ee1\u8db3\u65f6\u8df3\u8f6c\u81f3\u504f\u79fb\u91cf0x19）\u3002<\/p>\n

\u8df3\u8f6c\u76ee\u6807：\u76ee\u6807\u5730\u5740 0x19 \u5728\u6c47\u7f16\u9636\u6bb5\u5df2\u8ba1\u7b97\u4e3a\u7edd\u5bf9\u504f\u79fb，\u65e0\u9700\u91cd\u5b9a\u4f4d\u3002<\/p>\n

4.4.1.3 \u9519\u8bef\u5904\u7406\u5206\u652f（.L6）<\/p>\n

\u6c47\u7f16\u4ee3\u7801（hello.s）：<\/p>\n

\"\"<\/p>\n

\u53cd\u6c47\u7f16（hello.o）：<\/p>\n

\"\"\u5206\u6790：<\/p>\n

\u5b57\u7b26\u4e32\u52a0\u8f7d（.LC0）：<\/p>\n

\u673a\u5668\u7801：48 8d 3d 00 00 00 00<\/p>\n

lea\u6307\u4ee4\u7684PC\u76f8\u5bf9\u5bfb\u5740，\u5360\u4f4d\u7b26 00 00 00 00 \u9700\u91cd\u5b9a\u4f4d<\/p>\n

\u91cd\u5b9a\u4f4d\u6761\u76ee：R_X86_64_PC32<\/p>\n

\u4fee\u6b63\u503c = .LC0\u5730\u5740 – \u4e0b\u4e00\u6761\u6307\u4ee4\u5730\u5740（0x20） – 4<\/p>\n

\u51fd\u6570\u8c03\u7528（puts@PLT）：<\/p>\n

\u673a\u5668\u7801：e8 00 00 00 00<\/p>\n

call\u6307\u4ee4\u7684PLT\u8868\u8df3\u8f6c，\u5360\u4f4d\u7b26\u9700\u94fe\u63a5\u5668\u586b\u5145<\/p>\n

\u91cd\u5b9a\u4f4d\u6761\u76ee：R_X86_64_PLT32<\/p>\n

\u4fee\u6b63\u503c = puts@PLT\u5165\u53e3\u5730\u5740 – \u4e0b\u4e00\u6761\u6307\u4ee4\u5730\u5740（0x25） – 4<\/p>\n

4.4.1.4 \u4e3b\u5faa\u73af\u903b\u8f91（.L2-.L3）<\/p>\n

\u6c47\u7f16\u4ee3\u7801（hello.s）：<\/p>\n

\"\"<\/p>\n

\u53cd\u6c47\u7f16（hello.o）：<\/p>\n

\"\"<\/p>\n

\u5206\u6790：<\/p>\n

(1)\u53c2\u6570\u4f20\u9012\u673a\u5236<\/p>\n

argv\u8bbf\u95ee： %rbx \u5b58\u50a8 argv \u6570\u7ec4\u57fa\u5740，\u504f\u79fb\u91cf\u8ba1\u7b97<\/p>\n

mov 0x8(%rbx), %rsi\u00a0\u00a0 # argv[1] = *(argv + 8)\u00a0 \u673a\u5668\u7801 48 8b 73 08<\/p>\n

48：64\u4f4d\u64cd\u4f5c\u6570\u524d\u7f00 8b 73 08：mov\u6307\u4ee4\u7f16\u7801，\u6e90\u5730\u5740\u4e3a %rbx + 8<\/p>\n

printf\u53c2\u6570\u4f20\u9012：<\/p>\n

\u5bc4\u5b58\u5668\u987a\u5e8f：%rdi（\u683c\u5f0f\u4e32）\u3001%rsi（argv[1]）\u3001%rdx（argv[2]）\u3001%rcx（argv[3]）\u3002<\/p>\n

\u6d6e\u70b9\u5904\u7406：mov $0x0, %eax \u8868\u793a\u65e0\u5411\u91cf\u5bc4\u5b58\u5668\u53c2\u6570\u3002<\/p>\n

(2)\u63a7\u5236\u6d41\u4e0e\u91cd\u5b9a\u4f4d<\/p>\n

\u5faa\u73af\u8df3\u8f6c（jle .L3）\u00a0 \u673a\u5668\u7801：7e cb<\/p>\n

7e：jle\u64cd\u4f5c\u7801\u00a0 cb：8\u4f4d\u504f\u79fb\u91cf（\u8865\u7801 -53），\u76ee\u6807\u5730\u5740\u4e3a 0x62 – 53 + 2 = 0x2f<\/p>\n

\u65e0\u9700\u91cd\u5b9a\u4f4d，\u504f\u79fb\u91cf\u5728\u6c47\u7f16\u9636\u6bb5\u786e\u5b9a\u3002<\/p>\n

\u5916\u90e8\u51fd\u6570\u8c03\u7528（sleep@PLT） \u673a\u5668\u7801：e8 00 00 00 00<\/p>\n

\u5360\u4f4d\u7b26 00 00 00 00 \u9700\u94fe\u63a5\u5668\u586b\u5145<\/p>\n

R_X86_64_PLT32，\u901a\u8fc7PLT\u8868\u5b9e\u73b0\u52a8\u6001\u94fe\u63a5\u3002<\/p>\n

4.4.1.5 \u7a0b\u5e8f\u9000\u51fa\u4e0e\u6808\u5e27\u56de\u6536<\/p>\n

\u6c47\u7f16\u4ee3\u7801（hello.s）：<\/p>\n

\"\"<\/p>\n

\u53cd\u6c47\u7f16（hello.o）：<\/p>\n

\"\"<\/p>\n

\u5206\u6790：<\/p>\n

\u6808\u5e73\u8861 addq $8, %rsp \u56de\u6536\u6808\u7a7a\u95f4，popq\u6062\u590d\u4fdd\u5b58\u7684\u5bc4\u5b58\u5668<\/p>\n

\u8fd4\u56de\u503c mov $0x0, %eax \u8bbe\u7f6e\u8fd4\u56de\u503c0<\/p>\n

4.4.2 \u673a\u5668\u8bed\u8a00\u6784\u6210<\/p>\n

\u673a\u5668\u8bed\u8a00\u7531\u64cd\u4f5c\u7801\u548c\u64cd\u4f5c\u6570\u7ec4\u6210，\u4ee5\u4e8c\u8fdb\u5236\u5f62\u5f0f\u7f16\u7801，\u5177\u6709\u4ee5\u4e0b\u7279\u5f81：<\/p>\n

\u5b9a\u957f\u64cd\u4f5c\u7801 \u00a0call \u5bf9\u5e94 e8，movq \u5bf9\u5e94 48 8b<\/p>\n

\u53d8\u957f\u64cd\u4f5c\u6570 \u5730\u5740\u504f\u79fb\u3001\u7acb\u5373\u6570\u7b49\u957f\u5ea6\u53ef\u53d8（1-8\u5b57\u8282）<\/p>\n

\u6307\u4ee4\u524d\u7f00\u00a0\u00a0 \u00a048 \u8868\u793a64\u4f4d\u64cd\u4f5c\u6570，f3 0f 1e fa \u8868\u793a\u5b89\u5168\u6307\u4ee4 endbr64<\/p>\n

4.4.3\u673a\u5668\u8bed\u8a00\u4e0e\u6c47\u7f16\u8bed\u8a00\u7684\u6620\u5c04\u5173\u7cfb<\/p>\n\n\n\n\n\n\n\n
\n

\n<\/td>\n

\n

\u6c47\u7f16\u6307\u4ee4<\/p>\n<\/td>\n

\n

\u673a\u5668\u7801<\/p>\n<\/td>\n

\n

\u64cd\u4f5c\u6570\u7f16\u7801\u89e3\u6790<\/p>\n<\/td>\n<\/tr>\n

\n

\u6570\u636e\u64cd\u4f5c\u6307\u4ee4<\/p>\n<\/td>\n

\n

movq 8(%rbx), %rsi<\/p>\n<\/td>\n

\n

48 8b 73 08<\/p>\n<\/td>\n

\n

48（64\u4f4d\u524d\u7f00）+\u00a08b（mov）+\u00a073 08（%rbx+8\u00a0\u2192\u00a0%rsi）<\/p>\n<\/td>\n<\/tr>\n

\n

lea .LC0(%rip), %rdi<\/p>\n<\/td>\n

\n

48 8d 3d 00 00 00 00<\/p>\n<\/td>\n

\n

48 8d（lea）+\u00a03d（%rdi\u76ee\u6807）+\u00a000 00 00 00（\u91cd\u5b9a\u4f4d）<\/p>\n<\/td>\n<\/tr>\n

\n

\u63a7\u5236\u6d41<\/p>\n<\/td>\n

\n

call printf@PLT<\/p>\n<\/td>\n

\n

e8 00 00 00 00<\/p>\n<\/td>\n

\n

e8（call）+\u00a000 00 00 00（\u91cd\u5b9a\u4f4d）<\/p>\n<\/td>\n<\/tr>\n

\n

jle .L3<\/p>\n<\/td>\n

\n

7e cb<\/p>\n<\/td>\n

\n

7e（jle）+\u00a0cb（8\u4f4d\u504f\u79fb\u91cf\u00a0-53）<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

4.4.4\u673a\u5668\u8bed\u8a00\u4e0e\u6c47\u7f16\u8bed\u8a00\u4e0d\u4e00\u81f4\u6027\u5206\u6790<\/p>\n

\u5206\u652f\u8f6c\u79fb\u6307\u4ee4 \u5982jle .L3 \u2192 7e cb<\/p>\n

\u6c47\u7f16\u8bed\u8a00\u4f7f\u7528\u7b26\u53f7\u6807\u7b7e（.L3）\u673a\u5668\u8bed\u8a00\u7f16\u7801\u4e3a\u76f8\u5bf9\u504f\u79fb\u91cf，\u4e0e\u5f53\u524d\u6307\u4ee4\u5730\u5740\u65e0\u5173\u3002<\/p>\n

\u504f\u79fb\u8ba1\u7b97：\u76ee\u6807\u5730\u5740 0x2f = \u5f53\u524d\u5730\u5740 0x62 + \u504f\u79fb 0xcb（-53） + \u6307\u4ee4\u957f\u5ea6 2\u3002<\/p>\n

\u51fd\u6570\u8c03\u7528\u6307\u4ee4 \u5982call puts@PLT \u2192 e8 00 00 00 00<\/p>\n

\u6c47\u7f16\u8bed\u8a00\u663e\u5f0f\u6807\u6ce8\u7b26\u53f7（puts@PLT）\u673a\u5668\u8bed\u8a00\u4f7f\u7528\u5360\u4f4d\u7b26，\u4f9d\u8d56\u91cd\u5b9a\u4f4d\u6761\u76ee\u4fee\u6b63\u3002<\/p>\n

\u91cd\u5b9a\u4f4d\u4fee\u6b63：\u6839\u636e R_X86_64_PLT32 \u7c7b\u578b，\u94fe\u63a5\u65f6\u586b\u5145PLT\u8868\u504f\u79fb\u3002<\/p>\n

\u5730\u5740\u52a0\u8f7d\u6307\u4ee4\u00a0 \u5982lea .LC0(%rip), %rdi \u2192 48 8d 3d 00 00 00 00<\/p>\n

\u6c47\u7f16\u8bed\u8a00\u4f7f\u7528\u7b26\u53f7（.LC0）\u548c\u76f8\u5bf9\u5bfb\u5740（%rip）<\/p>\n

\u673a\u5668\u8bed\u8a00\u7f16\u7801\u4e3a PC\u76f8\u5bf9\u504f\u79fb\u5360\u4f4d\u7b26，\u9700\u91cd\u5b9a\u4f4d\u4fee\u6b63\u3002<\/p>\n

\u91cd\u5b9a\u4f4d\u4fee\u6b63：\u6839\u636e R_X86_64_PC32 \u7c7b\u578b，\u8ba1\u7b97 .LC0 \u4e0e %rip \u7684\u76f8\u5bf9\u504f\u79fb\u3002<\/p>\n

4.5 \u672c\u7ae0\u5c0f\u7ed3<\/h3>\n

\u672c\u7ae0\u5206\u6790\u4e86\u53ef\u91cd\u5b9a\u4f4d\u76ee\u6807\u6587\u4ef6 hello.o \u7684\u751f\u6210\u4e0e\u7ed3\u6784，\u63ed\u793a\u4e86\u6c47\u7f16\u5230\u673a\u5668\u8bed\u8a00\u7684\u8f6c\u6362\u673a\u5236\u3002\u76ee\u6807\u6587\u4ef6\u901a\u8fc7 .text \u8282\u5b58\u50a8\u673a\u5668\u6307\u4ee4，.rela.text \u8bb0\u5f55\u9700\u91cd\u5b9a\u4f4d\u7684\u7b26\u53f7\u5730\u5740\u3002\u673a\u5668\u8bed\u8a00\u7531\u64cd\u4f5c\u7801\u548c\u64cd\u4f5c\u6570\u6784\u6210，\u5206\u652f\u6307\u4ee4\u76f4\u63a5\u7f16\u7801\u76f8\u5bf9\u504f\u79fb，\u51fd\u6570\u8c03\u7528\u901a\u8fc7\u5360\u4f4d\u7b26\u9884\u7559\u91cd\u5b9a\u4f4d\u7a7a\u95f4\u3002\u5b89\u5168\u8bbe\u8ba1\u4e0a，endbr64 \u6307\u4ee4\u4e0eELF\u5c5e\u6027\u8282\u589e\u5f3a\u4e86\u63a7\u5236\u6d41\u5b8c\u6574\u6027\u3002\u672c\u7ae0\u4e3a\u7406\u89e3\u94fe\u63a5\u8fc7\u7a0b\u4e0e\u6307\u4ee4\u96c6\u67b6\u6784\u534f\u4f5c\u63d0\u4f9b\u4e86\u5e95\u5c42\u89c6\u89d2\u3002<\/p>\n<\/p>\n

\u7b2c5\u7ae0 \u94fe\u63a5<\/h2>\n

5.1 \u94fe\u63a5\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528<\/h3>\n

\u94fe\u63a5\u662f\u5c06\u591a\u4e2a\u76ee\u6807\u6587\u4ef6\u548c\u5e93\u6587\u4ef6\u5408\u5e76\u4e3a\u53ef\u6267\u884c\u6587\u4ef6\u7684\u8fc7\u7a0b，\u5305\u62ec：<\/p>\n

\u7b26\u53f7\u89e3\u6790：\u5c06\u672a\u5b9a\u4e49\u7684\u7b26\u53f7（\u5982 printf）\u7ed1\u5b9a\u5230\u52a8\u6001\u5e93\u4e2d\u7684\u5b9e\u9645\u5730\u5740<\/p>\n

\u5730\u5740\u91cd\u5b9a\u4f4d：\u4fee\u6b63\u4ee3\u7801\u548c\u6570\u636e\u6bb5\u7684\u7edd\u5bf9\u5730\u5740，\u751f\u6210\u53ef\u6267\u884c\u5185\u5b58\u5e03\u5c40<\/p>\n

\u8282\u5408\u5e76：\u6574\u5408\u4e0d\u540c\u76ee\u6807\u6587\u4ef6\u7684 .text\u3001.data \u7b49\u8282，\u751f\u6210\u6700\u7ec8ELF\u7ed3\u6784<\/p>\n

5.2 \u5728Ubuntu\u4e0b\u94fe\u63a5\u7684\u547d\u4ee4<\/h3>\n

\"\"<\/p>\n

-dynamic-linker：\u6307\u5b9a\u52a8\u6001\u94fe\u63a5\u5668\u8def\u5f84 crt1.o \u63d0\u4f9b\u7a0b\u5e8f\u5165\u53e3 _start<\/p>\n

crti.o \u548c crtn.o \u5305\u542b\u521d\u59cb\u5316\u4ee3\u7801\u00a0 -lc \u94fe\u63a5 libc.so，\u63d0\u4f9b\u6807\u51c6\u5e93\u51fd\u6570<\/p>\n

5.3 \u53ef\u6267\u884c\u76ee\u6807\u6587\u4ef6hello\u7684\u683c\u5f0f<\/h3>\n

\"\"<\/p>\n\n\n\n\n\n\n\n\n\n\n
\n

\u6bb5\u540d<\/p>\n<\/td>\n

\n

\u8d77\u59cb\u5730\u5740<\/p>\n<\/td>\n

\n

\u5927\u5c0f<\/p>\n<\/td>\n

\n

\u6743\u9650<\/p>\n<\/td>\n

\n

\u8bf4\u660e<\/p>\n<\/td>\n<\/tr>\n

\n

.interp<\/p>\n<\/td>\n

\n

0x4002e0<\/p>\n<\/td>\n

\n

0x1c<\/p>\n<\/td>\n

\n

R<\/p>\n<\/td>\n

\n

\u5b58\u50a8\u52a8\u6001\u94fe\u63a5\u5668\u8def\u5f84<\/p>\n<\/td>\n<\/tr>\n

\n

.plt<\/p>\n<\/td>\n

\n

0x401020<\/p>\n<\/td>\n

\n

0x70<\/p>\n<\/td>\n

\n

RX<\/p>\n<\/td>\n

\n

\u8fc7\u7a0b\u94fe\u63a5\u8868（PLT），\u7528\u4e8e\u8df3\u8f6c\u5230\u52a8\u6001\u5e93\u51fd\u6570<\/p>\n<\/td>\n<\/tr>\n

\n

.text<\/p>\n<\/td>\n

\n

0x4010f0<\/p>\n<\/td>\n

\n

0xaa<\/p>\n<\/td>\n

\n

RX<\/p>\n<\/td>\n

\n

\u4e3b\u7a0b\u5e8f\u4ee3\u7801，\u5305\u542b\u00a0_start\u3001main\u00a0\u548c\u00a0<\/p>\n

_dl_relocate_static_pie<\/p>\n<\/td>\n<\/tr>\n

\n

.rodata<\/p>\n<\/td>\n

\n

0x402000<\/p>\n<\/td>\n

\n

0x48<\/p>\n<\/td>\n

\n

R<\/p>\n<\/td>\n

\n

\u53ea\u8bfb\u6570\u636e\u6bb5，\u5b58\u50a8\u5b57\u7b26\u4e32\u5e38\u91cf<\/p>\n<\/td>\n<\/tr>\n

\n

.got.plt<\/p>\n<\/td>\n

\n

0x403fe8<\/p>\n<\/td>\n

\n

0x48<\/p>\n<\/td>\n

\n

RW<\/p>\n<\/td>\n

\n

\u5168\u5c40\u504f\u79fb\u8868（GOT），\u5b58\u50a8\u52a8\u6001\u5e93\u51fd\u6570\u7684\u5b9e\u9645\u5730\u5740<\/p>\n<\/td>\n<\/tr>\n

\n

.data<\/p>\n<\/td>\n

\n

0x404030<\/p>\n<\/td>\n

\n

0x4<\/p>\n<\/td>\n

\n

RW<\/p>\n<\/td>\n

\n

\u5df2\u521d\u59cb\u5316\u7684\u5168\u5c40\u6570\u636e<\/p>\n<\/td>\n<\/tr>\n

\n

.dynamic<\/p>\n<\/td>\n

\n

0x403e38<\/p>\n<\/td>\n

\n

0x1a0<\/p>\n<\/td>\n

\n

RW<\/p>\n<\/td>\n

\n

\u52a8\u6001\u94fe\u63a5\u4fe1\u606f，\u5305\u542b\u4f9d\u8d56\u5e93\u5217\u8868\u548c\u91cd\u5b9a\u4f4d\u6761\u76ee<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\n

5.4 hello\u7684\u865a\u62df\u5730\u5740\u7a7a\u95f4<\/h3>\n

\u4f7f\u7528edb\u52a0\u8f7dhello，\u67e5\u770b\u865a\u62df\u5730\u5740\u7a7a\u95f4\u5404\u6bb5\u4fe1\u606f，\u5e76\u4e0e5.3\u5bf9\u7167\u5206\u6790<\/p>\n

\"\"<\/p>\n

\u901a\u8fc7\u5bf9\u6bd4edb\u52a0\u8f7d\u7684\u865a\u62df\u5730\u5740\u7a7a\u95f4\u4fe1\u606f\u4e0e5.3\u4e2d\u7684ELF\u6bb5\u4fe1\u606f，\u5206\u6790\u5982\u4e0b：<\/p>\n

1. \u53ea\u8bfb\u4ee3\u7801\u6bb5（R–\/R-X）<\/p>\n

\u5185\u5b58\u533a\u57df：<\/p>\n

\"\"<\/p>\n

\u5bf9\u5e94ELF\u6bb5：<\/p>\n

0x400000-0x401000（R–）：\u5305\u542b.interp（0x4002e0）\u3001.note\u3001.hash\u7b49\u53ea\u8bfb\u6bb5，\u4e0eELF\u6743\u9650\u4e00\u81f4<\/p>\n

0x401000-0x402000（R-X）：\u5305\u542b\u53ef\u6267\u884c\u6bb5.plt（0x401020）\u3001.text（0x4010f0），\u6743\u9650\u4e0eELF\u4e2d\u6807\u8bb0\u7684RX\u5b8c\u5168\u5339\u914d<\/p>\n

0x402000-0x403000（R–）：\u5bf9\u5e94\u53ea\u8bfb\u6570\u636e\u6bb5.rodata（0x402000），\u6743\u9650\u4e00\u81f4<\/p>\n

2. \u53ef\u8bfb\u5199\u6570\u636e\u6bb5（RW）<\/p>\n

\u5185\u5b58\u533a\u57df：<\/p>\n

\"\"<\/p>\n

\u5bf9\u5e94ELF\u6bb5：<\/p>\n

.dynamic（0x403e38）：\u5b58\u50a8\u52a8\u6001\u94fe\u63a5\u4fe1\u606f，\u6743\u9650\u4e3aRW\u3002<\/p>\n

.got.plt（0x403fe8）：\u5168\u5c40\u504f\u79fb\u8868，\u9700\u8fd0\u884c\u65f6\u4fee\u6539，\u6743\u9650\u4e3aRW\u3002<\/p>\n

.data（0x404030）：\u5df2\u521d\u59cb\u5316\u5168\u5c40\u6570\u636e，\u6743\u9650\u4e3aRW\u3002<\/p>\n

3. \u52a8\u6001\u94fe\u63a5\u5e93\u4e0e\u7cfb\u7edf\u533a\u57df<\/p>\n

\u5185\u5b58\u533a\u57df：<\/p>\n

\"\"<\/p>\n

\"\"<\/p>\n

[stack]\u3001[vvar]\u3001[vdso]\u3001[vsyscall]\u4e3a\u7cfb\u7edf\u4fdd\u7559\u533a\u57df<\/p>\n

\u52a8\u6001\u94fe\u63a5\u5e93\u7684\u6bb5\u4e0d\u5c5e\u4e8ehello\u7684ELF\u6587\u4ef6，\u4f46\u5728\u8fdb\u7a0b\u865a\u62df\u5730\u5740\u7a7a\u95f4\u4e2d\u52a0\u8f7d<\/p>\n

[stack]\u4e3a\u8fd0\u884c\u65f6\u6808,[vdso]\u4e3a\u5185\u6838\u63d0\u4f9b\u7684\u865a\u62df\u52a8\u6001\u5171\u4eab\u5bf9\u8c61，\u4e0e5.3\u4e2d\u7684\u6bb5\u65e0\u5173<\/p>\n

4. \u6743\u9650\u5408\u5e76\u4e0e\u5bf9\u9f50<\/p>\n

ELF\u6587\u4ef6\u4e2d\u7684\u591a\u4e2a\u6bb5（\u5982.interp\u3001.note）\u88ab\u5408\u5e76\u5230\u540c\u4e00\u5185\u5b58\u9875（0x400000-0x401000），\u6743\u9650\u53d6\u5e76\u96c6（R–）\u3002<\/p>\n

\u53ef\u6267\u884c\u6bb5（.text\u3001.plt）\u5408\u5e76\u5230R-X\u533a\u57df，\u7b26\u5408\u4ee3\u7801\u6bb5\u7684\u5178\u578b\u6743\u9650\u3002<\/p>\n

5.5 \u94fe\u63a5\u7684\u91cd\u5b9a\u4f4d\u8fc7\u7a0b\u5206\u6790<\/h3>\n

\u5bf9\u6bd4 hello.o \u548c hello \u7684\u53cd\u6c47\u7f16\u4ee3\u7801，\u89e3\u6790\u91cd\u5b9a\u4f4d\u8fc7\u7a0b<\/p>\n

1. \u51fd\u6570\u8c03\u7528\u91cd\u5b9a\u4f4d（\u4ee5 printf \u4e3a\u4f8b）<\/p>\n

hello.o \u4e2d\u7684\u672a\u89e3\u6790\u8c03\u7528：<\/p>\n

\"\"<\/p>\n

hello \u4e2d\u7684\u91cd\u5b9a\u4f4d\u7ed3\u679c：<\/p>\n

\"\"<\/p>\n

PLT\u6761\u76ee（0x4010a0）：<\/p>\n

\"\"<\/p>\n

GOT\u6761\u76ee\u521d\u59cb\u503c：\u9996\u6b21\u8c03\u7528\u65f6，GOT[printf] \u6307\u5411PLT\u4e2d\u7684\u89e3\u6790\u4ee3\u7801，\u89e6\u53d1\u52a8\u6001\u94fe\u63a5\u5668\u52a0\u8f7d printf \u7684\u5b9e\u9645\u5730\u5740\u3002<\/p>\n

2. \u6570\u636e\u5730\u5740\u91cd\u5b9a\u4f4d（\u4ee5\u5b57\u7b26\u4e32\u5e38\u91cf\u4e3a\u4f8b）<\/p>\n

hello.o \u4e2d\u7684\u672a\u89e3\u6790\u5730\u5740：<\/p>\n

\"\"<\/p>\n

hello \u4e2d\u7684\u91cd\u5b9a\u4f4d\u7ed3\u679c：<\/p>\n

\"\"<\/p>\n

\u5b57\u7b26\u4e32\u5e38\u91cf\u4f4d\u7f6e：.rodata \u6bb5\u7684 0x402038 \u5b58\u50a8 "Hello %s %s %s\\\\n"\u3002<\/p>\n

5.6 hello\u7684\u6267\u884c\u6d41\u7a0b<\/h3>\n

\"\"<\/p>\n

1. \u52a8\u6001\u52a0\u8f7d\u9636\u6bb5<\/p>\n

\u5165\u53e3\u51fd\u6570：_start（\u52a8\u6001\u94fe\u63a5\u5668）<\/p>\n

\u5730\u5740：0x00007ffff7fe4540（\u4f4d\u4e8e ld-linux-x86-64.so.2）<\/p>\n

\u4f5c\u7528：\u52a0\u8f7d\u7a0b\u5e8f\u4f9d\u8d56\u7684\u5171\u4eab\u5e93（\u5982 libc.so.6），\u521d\u59cb\u5316\u8fd0\u884c\u73af\u5883\u3002<\/p>\n

2. \u7a0b\u5e8f\u542f\u52a8\u9636\u6bb5<\/p>\n

\u5165\u53e3\u51fd\u6570：_start（hello\u7a0b\u5e8f）<\/p>\n

\u5730\u5740：0x4010f0（.text\u6bb5）<\/p>\n

\u64cd\u4f5c：\u8c03\u7528 __libc_start_main，\u4f20\u9012 main \u51fd\u6570\u5730\u5740\u3002<\/p>\n

\u8c03\u7528：call\u00a0\u00a0 *0x403fd8\u00a0\u00a0 ; \u8c03\u7528 __libc_start_main@GLIBC_2.34\u00a0<\/p>\n

3.\u4e3b\u51fd\u6570\u6267\u884c\u9636\u6bb5<\/p>\n

\u5165\u53e3\u51fd\u6570：main<\/p>\n

\u5730\u5740：0x401125<\/p>\n

\u6267\u884c\u6d41\u7a0b：<\/p>\n

(1)\u53c2\u6570\u68c0\u67e5：<\/p>\n

cmpl $0x5, %edi\u00a0 ; \u68c0\u67e5 argc \u662f\u5426\u4e3a5\u00a0<\/p>\n

jne 0x40113e\u00a0\u00a0\u00a0\u00a0 ; \u8df3\u8f6c\u5230\u9519\u8bef\u5904\u7406\u5206\u652f\u00a0<\/p>\n

(2)\u5faa\u73af\u903b\u8f91：<\/p>\n

\u5faa\u73af\u8ba1\u6570\u5668：%ebp \u4ece0\u9012\u589e\u81f39\u3002<\/p>\n

\u51fd\u6570\u8c03\u7528\u94fe：<\/p>\n\n\n\n\n\n\n
\n

\u51fd\u6570\u8c03\u7528<\/p>\n<\/td>\n

\n

\u5730\u5740<\/p>\n<\/td>\n

\n

\u4f5c\u7528<\/p>\n<\/td>\n<\/tr>\n

\n

printf@plt<\/p>\n<\/td>\n

\n

0x4010a0<\/p>\n<\/td>\n

\n

\u8f93\u51fa\u683c\u5f0f\u5316\u5b57\u7b26\u4e32<\/p>\n<\/td>\n<\/tr>\n

\n

atoi@plt<\/p>\n<\/td>\n

\n

0x4010c0<\/p>\n<\/td>\n

\n

\u5c06\u5b57\u7b26\u4e32\u53c2\u6570\u8f6c\u6362\u4e3a\u6574\u6570<\/p>\n<\/td>\n<\/tr>\n

\n

sleep@plt<\/p>\n<\/td>\n

\n

0x4010e0<\/p>\n<\/td>\n

\n

\u4f11\u7720\u6307\u5b9a\u79d2\u6570<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u5faa\u73af\u7ec8\u6b62\u6761\u4ef6：cmpl $0x9, %ebp\u00a0<\/p>\n

jle \u5faa\u73af\u4f53\u00a0<\/p>\n

4. \u4e2d\u65ad\u5904\u7406\u9636\u6bb5<\/p>\n

\u89e6\u53d1\u6761\u4ef6：\u7528\u6237\u6309\u4e0b Ctrl-C（\u53d1\u9001 SIGINT \u4fe1\u53f7）\u3002<\/p>\n

\u8c03\u7528\u94fe：<\/p>\n\n\n\n\n\n\n\n
\n

\u51fd\u6570\u540d<\/p>\n<\/td>\n

\n

\u5730\u5740<\/p>\n<\/td>\n

\n

\u4f5c\u7528<\/p>\n<\/td>\n<\/tr>\n

\n

__GI___clock_nanosleep<\/p>\n<\/td>\n

\n

0x00007ffff7ceca7a<\/p>\n<\/td>\n

\n

\u5185\u6838\u7ea7\u4f11\u7720\u5b9e\u73b0<\/p>\n<\/td>\n<\/tr>\n

\n

__GI___nanosleep<\/p>\n<\/td>\n

\n

0x00007ffff7cf9a27<\/p>\n<\/td>\n

\n

\u8c03\u7528\u00a0clock_nanosleep<\/p>\n<\/td>\n<\/tr>\n

\n

__sleep<\/p>\n<\/td>\n

\n

0x00007ffff7d0ec63<\/p>\n<\/td>\n

\n

\u5c01\u88c5\u00a0nanosleep\u00a0\u7cfb\u7edf\u8c03\u7528<\/p>\n<\/td>\n<\/tr>\n

\n

main<\/p>\n<\/td>\n

\n

0x401181<\/p>\n<\/td>\n

\n

\u4e3b\u51fd\u6570\u4e2d\u7684\u00a0sleep\u00a0\u8c03\u7528\u70b9<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

5. \u7a0b\u5e8f\u7ec8\u6b62\u9636\u6bb5<\/p>\n

\u6b63\u5e38\u7ec8\u6b62： main \u8fd4\u56de\u540e，__libc_start_main \u8c03\u7528 exit \u7ec8\u6b62\u8fdb\u7a0b\u3002<\/p>\n

\u4e2d\u65ad\u7ec8\u6b62： \u5185\u6838\u76f4\u63a5\u7ec8\u6b62\u8fdb\u7a0b，\u91ca\u653e\u8d44\u6e90\u3002<\/p>\n

5.7 Hello\u7684\u52a8\u6001\u94fe\u63a5\u5206\u6790<\/h3>\n

1. \u52a8\u6001\u94fe\u63a5\u524d\u7684GOT\u72b6\u6001<\/p>\n

\u5728\u7a0b\u5e8f\u9996\u6b21\u8c03\u7528\u5916\u90e8\u51fd\u6570\u524d，GOT\u6761\u76ee\u6307\u5411PLT\u4e2d\u7684\u89e3\u6790\u4ee3\u7801\u3002<\/p>\n

\u8c03\u8bd5\u547d\u4ee4\u4e0e\u8f93\u51fa：<\/p>\n

\"\"<\/p>\n

printf@got.plt（0x404008）\u521d\u59cb\u503c\u4e3a 0x00401040，\u6307\u5411 printf@plt+0x10<\/p>\n

atoi@got.plt（0x404018）\u521d\u59cb\u503c\u4e3a 0x00401060，\u6307\u5411 atoi@plt+0x10\u3002<\/p>\n

2. \u52a8\u6001\u94fe\u63a5\u540e\u7684GOT\u72b6\u6001<\/p>\n

\u9996\u6b21\u8c03\u7528\u51fd\u6570\u540e，\u52a8\u6001\u94fe\u63a5\u5668（ld.so）\u89e3\u6790\u5b9e\u9645\u51fd\u6570\u5730\u5740\u5e76\u66f4\u65b0GOT\u3002<\/p>\n

\u8c03\u8bd5\u547d\u4ee4\u4e0e\u8f93\u51fa：<\/p>\n

\"\"<\/p>\n

printf@got.plt（0x404008）\u66f4\u65b0\u4e3a0x7ffff7c60100,\u6307\u5411libc.so\u4e2d\u7684printf\u5b9e\u9645\u5730\u5740\u3002<\/p>\n

atoi@got.plt（0x404018）\u66f4\u65b0\u4e3a 0x7ffff7c46660，\u6307\u5411libc.so\u4e2d\u7684atoi\u5b9e\u9645\u5730\u5740\u3002<\/p>\n

5.8 \u672c\u7ae0\u5c0f\u7ed3<\/h3>\n

\u672c\u7ae0\u5206\u6790\u4e86hello\u7a0b\u5e8f\u4ece\u76ee\u6807\u6587\u4ef6\u5230\u53ef\u6267\u884c\u6587\u4ef6\u7684\u94fe\u63a5\u8fc7\u7a0b\u53ca\u5176\u8fd0\u884c\u673a\u5236\u3002\u94fe\u63a5\u901a\u8fc7\u7b26\u53f7\u89e3\u6790\u3001\u5730\u5740\u91cd\u5b9a\u4f4d\u548c\u8282\u5408\u5e76\u751f\u6210ELF\u7ed3\u6784，\u5173\u952e\u6bb5\u5305\u62ec.text（\u4ee3\u7801）\u3001.rodata（\u53ea\u8bfb\u6570\u636e）\u548c.got.plt（\u52a8\u6001\u51fd\u6570\u5730\u5740）\u3002\u865a\u62df\u5730\u5740\u7a7a\u95f4\u4e2d，ELF\u6bb5\u6743\u9650\u4e0e\u5185\u5b58\u6620\u5c04\u4e00\u81f4，\u7cfb\u7edf\u533a\u57df\u7531\u5185\u6838\u72ec\u7acb\u7ba1\u7406\u3002\u91cd\u5b9a\u4f4d\u4fee\u6b63\u51fd\u6570\u8c03\u7528\u81f3PLT，\u52a8\u6001\u94fe\u63a5\u901a\u8fc7GOT\u5b9e\u73b0\u5ef6\u8fdf\u7ed1\u5b9a：\u9996\u6b21\u8c03\u7528\u89e6\u53d1\u5730\u5740\u89e3\u6790\u5e76\u66f4\u65b0GOT\u4e3a\u5b9e\u9645\u5730\u5740\u3002\u7a0b\u5e8f\u6267\u884c\u6d41\u7a0b\u4ece\u52a8\u6001\u52a0\u8f7d\u5668ld.so\u521d\u59cb\u5316\u5f00\u59cb，\u7ecf_start\u8c03\u7528main，\u5faa\u73af\u8f93\u51fa\u4fe1\u606f\u540e\u901a\u8fc7exit\u6216\u4fe1\u53f7\u7ec8\u6b62\u3002<\/p>\n<\/p>\n

\u7b2c6\u7ae0 hello\u8fdb\u7a0b\u7ba1\u7406<\/h2>\n

6.1 \u8fdb\u7a0b\u7684\u6982\u5ff5\u4e0e\u4f5c\u7528<\/h3>\n

\u8fdb\u7a0b\u662f\u7a0b\u5e8f\u7684\u6267\u884c\u5b9e\u4f8b，\u62e5\u6709\u72ec\u7acb\u7684\u5730\u5740\u7a7a\u95f4\u3001\u4ee3\u7801\u3001\u6570\u636e\u548c\u7cfb\u7edf\u8d44\u6e90<\/p>\n

\u4f5c\u7528：<\/p>\n

\u8d44\u6e90\u5206\u914d：CPU\u65f6\u95f4\u7247\u3001\u5185\u5b58\u3001\u6587\u4ef6\u53e5\u67c4\u7b49\u7531\u64cd\u4f5c\u7cfb\u7edf\u7edf\u4e00\u7ba1\u7406<\/p>\n

\u9694\u79bb\u4fdd\u62a4：\u8fdb\u7a0b\u95f4\u76f8\u4e92\u9694\u79bb，\u907f\u514d\u6570\u636e\u51b2\u7a81\u6216\u975e\u6cd5\u8bbf\u95ee<\/p>\n

\u5e76\u53d1\u6267\u884c：\u901a\u8fc7\u8fdb\u7a0b\u8c03\u5ea6\u5b9e\u73b0\u591a\u4efb\u52a1\u5e76\u884c<\/p>\n

6.2 \u7b80\u8ff0\u58f3Shell-bash\u7684\u4f5c\u7528\u4e0e\u5904\u7406\u6d41\u7a0b<\/h3>\n

\u4f5c\u7528：<\/p>\n

\u547d\u4ee4\u89e3\u6790：\u89e3\u6790\u7528\u6237\u8f93\u5165\u7684\u547d\u4ee4（\u5982 .\/hello）\u3002<\/p>\n

\u8fdb\u7a0b\u7ba1\u7406：\u521b\u5efa\u5b50\u8fdb\u7a0b\u6267\u884c\u7a0b\u5e8f（fork + execve），\u652f\u6301\u540e\u53f0\u8fd0\u884c（&）\u3002<\/p>\n

\u73af\u5883\u7ba1\u7406：\u7ef4\u62a4\u73af\u5883\u53d8\u91cf（\u5982 PATH）\u548c\u8f93\u5165\u8f93\u51fa\u91cd\u5b9a\u5411（>\u3001<）\u3002<\/p>\n

\u5904\u7406\u6d41\u7a0b：<\/p>\n

1.\u8bfb\u53d6\u8f93\u5165：\u4ece\u7ec8\u7aef\u6216\u811a\u672c\u83b7\u53d6\u547d\u4ee4\u3002<\/p>\n

2.\u89e3\u6790\u547d\u4ee4：\u5206\u5272\u53c2\u6570，\u5904\u7406\u7ba1\u9053（|）\u3001\u91cd\u5b9a\u5411\u7b49\u3002<\/p>\n

3.\u6267\u884c\u547d\u4ee4：\u82e5\u4e3a\u5185\u7f6e\u547d\u4ee4（\u5982 cd），\u76f4\u63a5\u6267\u884c；\u5426\u5219\u521b\u5efa\u5b50\u8fdb\u7a0b\u8fd0\u884c\u7a0b\u5e8f\u3002<\/p>\n

6.3 Hello\u7684fork\u8fdb\u7a0b\u521b\u5efa\u8fc7\u7a0b<\/h3>\n

\u8c03\u7528fork()：Shell\u521b\u5efa\u5b50\u8fdb\u7a0b，\u590d\u5236\u7236\u8fdb\u7a0b\u7684\u5730\u5740\u7a7a\u95f4\u3001\u6587\u4ef6\u63cf\u8ff0\u7b26\u7b49<\/p>\n

\u8fd4\u56de\u503c\u533a\u5206：<\/p>\n

\u7236\u8fdb\u7a0b：fork() \u8fd4\u56de\u5b50\u8fdb\u7a0bPID<\/p>\n

\u5b50\u8fdb\u7a0b：fork() \u8fd4\u56de0<\/p>\n

\u5b50\u8fdb\u7a0b\u4efb\u52a1：\u8c03\u7528 execve() \u52a0\u8f7d hello \u7a0b\u5e8f，\u66ff\u6362\u5f53\u524d\u8fdb\u7a0b\u6620\u50cf<\/p>\n

6.4 Hello\u7684execve\u8fc7\u7a0b<\/h3>\n

\u529f\u80fd：\u52a0\u8f7d\u5e76\u6267\u884c hello \u7a0b\u5e8f，\u66ff\u6362\u5f53\u524d\u8fdb\u7a0b\u7684\u4ee3\u7801\u6bb5\u3001\u6570\u636e\u6bb5\u548c\u5806\u6808<\/p>\n

\u53c2\u6570\u4f20\u9012：<\/p>\n

argv：\u547d\u4ee4\u884c\u53c2\u6570\u6570\u7ec4（["\u5b66\u53f7", "\u59d3\u540d", …]）<\/p>\n

envp：\u73af\u5883\u53d8\u91cf\u6570\u7ec4（\u5982 PATH=\/usr\/bin）<\/p>\n

\u6267\u884c\u540e：<\/p>\n

\u8fdb\u7a0b\u7684\u5165\u53e3\u70b9\u53d8\u4e3a hello \u7684 _start \u51fd\u6570<\/p>\n

6.5 Hello\u7684\u8fdb\u7a0b\u6267\u884c<\/h3>\n

\u8fdb\u7a0b\u4e0a\u4e0b\u6587：\u5305\u62ec\u5bc4\u5b58\u5668\u503c\u3001\u7a0b\u5e8f\u8ba1\u6570\u5668（PC）\u3001\u6808\u6307\u9488（SP）\u7b49\u3002<\/p>\n

\u65f6\u95f4\u7247\u8c03\u5ea6：\u64cd\u4f5c\u7cfb\u7edf\u5206\u914dCPU\u65f6\u95f4\u7247（\u598210ms），\u65f6\u95f4\u8017\u5c3d\u540e\u89e6\u53d1\u65f6\u949f\u4e2d\u65ad，\u5207\u6362\u8fdb\u7a0b\u3002<\/p>\n

\u7528\u6237\u6001\u4e0e\u6838\u5fc3\u6001\u8f6c\u6362：<\/p>\n

\u7cfb\u7edf\u8c03\u7528（\u5982 sleep()）：\u4ece\u7528\u6237\u6001\u5207\u6362\u5230\u6838\u5fc3\u6001，\u6267\u884c\u5185\u6838\u4ee3\u7801\u3002<\/p>\n

\u4e2d\u65ad\u5904\u7406（\u5982 Ctrl-C）：\u5185\u6838\u63a5\u7ba1\u63a7\u5236\u6743，\u5904\u7406\u4fe1\u53f7\u540e\u8fd4\u56de\u7528\u6237\u6001\u3002<\/p>\n

6.6 hello\u7684\u5f02\u5e38\u4e0e\u4fe1\u53f7\u5904\u7406<\/h3>\n\n\n\n\n\n\n
\n

\u5f02\u5e38\u7c7b\u578b<\/p>\n<\/td>\n

\n

\u89e6\u53d1\u4fe1\u53f7<\/p>\n<\/td>\n

\n

\u5904\u7406\u65b9\u5f0f<\/p>\n<\/td>\n<\/tr>\n

\n

\u4e2d\u65ad（Ctrl-C）<\/p>\n<\/td>\n

\n

SIGINT<\/p>\n<\/td>\n

\n

\u7ec8\u6b62\u8fdb\u7a0b<\/p>\n<\/td>\n<\/tr>\n

\n

\u505c\u6b62（Ctrl-Z）<\/p>\n<\/td>\n

\n

SIGTSTP<\/p>\n<\/td>\n

\n

\u6302\u8d77\u8fdb\u7a0b\u81f3\u540e\u53f0<\/p>\n<\/td>\n<\/tr>\n

\n

\u975e\u6cd5\u64cd\u4f5c<\/p>\n<\/td>\n

\n

SIGSEGV<\/p>\n<\/td>\n

\n

\u7ec8\u6b62\u8fdb\u7a0b\u5e76\u751f\u6210\u6838\u5fc3\u8f6c\u50a8<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

1.Ctrl-Z \u6302\u8d77<\/p>\n

\"\"<\/p>\n

2.ps<\/p>\n

\"\"<\/p>\n

3.jobs<\/p>\n

\"\"<\/p>\n

4.pstree<\/p>\n

\"\"<\/p>\n

5.kill<\/p>\n

\"\"<\/p>\n

6.fg & Ctrl+C<\/p>\n

\"\"<\/p>\n

6.7\u672c\u7ae0\u5c0f\u7ed3<\/h3>\n

\u672c\u7ae0\u63a2\u8ba8\u4e86hello\u7a0b\u5e8f\u7684\u8fdb\u7a0b\u7ba1\u7406\u673a\u5236\u3002\u8fdb\u7a0b\u4f5c\u4e3a\u7a0b\u5e8f\u7684\u6267\u884c\u5b9e\u4f8b，\u4e3ahello\u63d0\u4f9b\u4e86\u8d44\u6e90\u5206\u914d\u3001\u9694\u79bb\u4fdd\u62a4\u548c\u5e76\u53d1\u6267\u884c\u7684\u80fd\u529b\u3002Shell（bash）\u901a\u8fc7\u89e3\u6790\u7528\u6237\u547d\u4ee4\u3001\u521b\u5efa\u5b50\u8fdb\u7a0b（fork）\u5e76\u52a0\u8f7d\u7a0b\u5e8f（execve）\u6765\u7ba1\u7406hello\u7684\u6267\u884c\u3002fork\u590d\u5236\u7236\u8fdb\u7a0b\u73af\u5883，\u800cexecve\u5c06hello\u7684\u4ee3\u7801\u548c\u6570\u636e\u8f7d\u5165\u5185\u5b58，\u5f00\u542f\u65b0\u7684\u6267\u884c\u6d41\u7a0b\u3002\u8fdb\u7a0b\u8fd0\u884c\u65f6，\u64cd\u4f5c\u7cfb\u7edf\u901a\u8fc7\u65f6\u95f4\u7247\u8c03\u5ea6\u548c\u4e0a\u4e0b\u6587\u5207\u6362\u5b9e\u73b0\u591a\u4efb\u52a1\u5e76\u884c，\u5e76\u5728\u7cfb\u7edf\u8c03\u7528\u6216\u4e2d\u65ad\u65f6\u5207\u6362\u7528\u6237\u6001\u4e0e\u6838\u5fc3\u6001\u3002\u6b64\u5916，hello\u9700\u5904\u7406\u5f02\u5e38\u548c\u4fe1\u53f7，\u5982SIGINT\u7ec8\u6b62\u8fdb\u7a0b\u3001SIGTSTP\u6302\u8d77\u8fdb\u7a0b，\u5e76\u901a\u8fc7ps\u3001jobs\u7b49\u5de5\u5177\u8fdb\u884c\u76d1\u63a7\u548c\u7ba1\u7406\u3002\u672c\u7ae0\u63ed\u793a\u4e86\u8fdb\u7a0b\u4ece\u521b\u5efa\u5230\u7ec8\u6b62\u7684\u5168\u751f\u547d\u5468\u671f，\u4f53\u73b0\u4e86\u64cd\u4f5c\u7cfb\u7edf\u5bf9\u7a0b\u5e8f\u6267\u884c\u7684\u6838\u5fc3\u63a7\u5236\u4f5c\u7528\u3002<\/p>\n<\/p>\n

\u7b2c7\u7ae0 hello\u7684\u5b58\u50a8\u7ba1\u7406<\/h2>\n

7.1 hello\u7684\u5b58\u50a8\u5668\u5730\u5740\u7a7a\u95f4<\/h3>\n

\u5728hello\u7a0b\u5e8f\u7684\u6267\u884c\u8fc7\u7a0b\u4e2d，\u5b58\u50a8\u5668\u5730\u5740\u901a\u8fc7\u591a\u7ea7\u62bd\u8c61\u5b9e\u73b0\u9ad8\u6548\u7ba1\u7406：<\/p>\n

\u903b\u8f91\u5730\u5740：\u7a0b\u5e8f\u6bb5\u5185\u7684\u504f\u79fb\u5730\u5740，\u7531\u7f16\u8bd1\u5668\u548c\u94fe\u63a5\u5668\u751f\u6210，\u5bf9\u5e94\u4ee3\u7801\u6bb5\u6216\u6570\u636e\u6bb5\u7684\u5c40\u90e8\u4f4d\u7f6e\u3002<\/p>\n

hello\u7684main\u51fd\u6570\u5728\u4ee3\u7801\u6bb5\u4e2d\u7684\u903b\u8f91\u5730\u5740\u4e3a0x4004d6，\u8868\u793a\u76f8\u5bf9\u4e8e\u4ee3\u7801\u6bb5\u57fa\u5740\u7684\u504f\u79fb\u3002<\/p>\n

\u7ebf\u6027\u5730\u5740：Intel\u5904\u7406\u5668\u901a\u8fc7\u6bb5\u5f0f\u7ba1\u7406\u5c06\u903b\u8f91\u5730\u5740\u8f6c\u6362\u4e3a\u5168\u5c40\u7ebf\u6027\u5730\u5740（\u6bb5\u57fa\u5740 + \u504f\u79fb）\u3002\u82e5hello\u7684\u4ee3\u7801\u6bb5\u57fa\u5740\u4e3a0x08048000，\u903b\u8f91\u5730\u57400x100\u8f6c\u6362\u4e3a\u7ebf\u6027\u5730\u57400x08048100\u3002<\/p>\n

\u865a\u62df\u5730\u5740：hello\u8fdb\u7a0b\u770b\u5230\u7684\u72ec\u7acb\u5730\u5740\u7a7a\u95f4（0x8048000），\u901a\u8fc7\u9875\u8868\u6620\u5c04\u5230\u7269\u7406\u5730\u5740，\u5b9e\u73b0\u8fdb\u7a0b\u95f4\u9694\u79bb\u3002<\/p>\n

\u7269\u7406\u5730\u5740：\u5b9e\u9645\u5185\u5b58\u82af\u7247\u4e0a\u7684\u786c\u4ef6\u5730\u5740，\u7531MMU\u901a\u8fc7\u9875\u8868\u8f6c\u6362\u5f97\u5230\u3002<\/p>\n

\u5f53hello\u6267\u884cprintf\u65f6，\u6307\u4ee4\u7684\u903b\u8f91\u5730\u5740（\u59820x4010a0）\u7ecf\u6bb5\u5f0f\u7ba1\u7406\u8f6c\u6362\u4e3a\u7ebf\u6027\u5730\u5740，\u518d\u901a\u8fc7\u9875\u5f0f\u7ba1\u7406\u6620\u5c04\u5230\u7269\u7406\u5730\u5740，\u6700\u7ec8\u8bbf\u95ee\u5185\u5b58\u4e2d\u7684\u5b57\u7b26\u4e32\u5e38\u91cf（.LC1\u4f4d\u4e8e.rodata\u6bb5）\u3002<\/p>\n

7.2 Intel\u903b\u8f91\u5730\u5740\u5230\u7ebf\u6027\u5730\u5740\u7684\u53d8\u6362-\u6bb5\u5f0f\u7ba1\u7406<\/h3>\n

Intel\u4f7f\u7528\u6bb5\u5f0f\u7ba1\u7406\u5b8c\u6210\u903b\u8f91\u5730\u5740\u5230\u7ebf\u6027\u5730\u5740\u7684\u8f6c\u6362：<\/p>\n

\u6bb5\u9009\u62e9\u7b26：\u4ee3\u7801\u6bb5\u5bc4\u5b58\u5668（CS）\u5b58\u50a8\u6bb5\u9009\u62e9\u7b26，\u6307\u5411\u5168\u5c40\u63cf\u8ff0\u7b26\u8868（GDT）\u4e2d\u7684\u6bb5\u63cf\u8ff0\u7b26\u3002<\/p>\n

\u6bb5\u63cf\u8ff0\u7b26：\u5305\u542b\u6bb5\u57fa\u5740\u3001\u754c\u9650\u548c\u6743\u9650\u3002hello\u7684\u4ee3\u7801\u6bb5\u57fa\u5740\u4e3a0x08048000\u3002<\/p>\n

\u7ebf\u6027\u5730\u5740\u8ba1\u7b97：\u7ebf\u6027\u5730\u5740 = \u6bb5\u57fa\u5740 + \u903b\u8f91\u504f\u79fb\u91cf\u3002<\/p>\n

hello\u7684main\u51fd\u6570\u903b\u8f91\u5730\u57400x4004d6，\u5728\u6bb5\u57fa\u57400x08048000\u4e0b\u8f6c\u6362\u4e3a\u7ebf\u6027\u5730\u57400x0804d4d6（\u5047\u8bbe\u6bb5\u57fa\u5740\u4e3a0x08048000）\u3002<\/p>\n

7.3 Hello\u7684\u7ebf\u6027\u5730\u5740\u5230\u7269\u7406\u5730\u5740\u7684\u53d8\u6362-\u9875\u5f0f\u7ba1\u7406<\/h3>\n

\u64cd\u4f5c\u7cfb\u7edf\u901a\u8fc7\u9875\u5f0f\u7ba1\u7406\u5c06\u865a\u62df\u5730\u5740（\u7ebf\u6027\u5730\u5740）\u6620\u5c04\u5230\u7269\u7406\u5730\u5740：<\/p>\n

\u5206\u9875\u673a\u5236：\u865a\u62df\u5730\u5740\u5212\u5206\u4e3a\u9875\u53f7\u548c\u9875\u5185\u504f\u79fb<\/p>\n

\n

\u9875\u8868\u67e5\u8be2：\u901a\u8fc7\u9875\u8868\u57fa\u5740\u5bc4\u5b58\u5668\u627e\u5230\u9875\u8868，\u9010\u7ea7\u67e5\u8be2\u56db\u7ea7\u9875\u8868\u9879（PML4\u2192PDPT\u2192PD\u2192PT），\u83b7\u53d6\u9875\u6846\u3002<\/p>\n

\u7269\u7406\u5730\u5740\u751f\u6210：\u7269\u7406\u5730\u5740 = PFN << 12 | Offset<\/p>\n

\u5047\u8bbehello\u8bbf\u95ee\u865a\u62df\u5730\u57400x402038（\u5b58\u50a8"Hello %s %s %s\\\\n"），\u9875\u53f7\u4e3a0x402，\u9875\u5185\u504f\u79fb0x038，\u901a\u8fc7\u9875\u8868\u67e5\u8be2PFN0x2000，\u7269\u7406\u5730\u5740\u4e3a0x2000038\u3002<\/p>\n

7.4 TLB\u4e0e\u56db\u7ea7\u9875\u8868\u652f\u6301\u4e0b\u7684VA\u5230PA\u7684\u53d8\u6362<\/h3>\n

\u73b0\u4ee3\u7cfb\u7edf\u901a\u8fc7TLB\u548c\u56db\u7ea7\u9875\u8868\u52a0\u901f\u5730\u5740\u8f6c\u6362：<\/p>\n

\u56db\u7ea7\u9875\u8868：\u865a\u62df\u5730\u5740\u5212\u5206\u4e3a4\u7ea7\u7d22\u5f15（\u59829+9+9+9+12\u4f4d），\u9010\u7ea7\u67e5\u8be2\u9875\u8868\u9879<\/p>\n

TLB\u7f13\u5b58：\u8f6c\u6362\u540e\u5907\u7f13\u51b2\u5668（TLB）\u7f13\u5b58\u8fd1\u671f\u9875\u8868\u9879\u3002\u82e5\u547d\u4e2d，\u76f4\u63a5\u83b7\u53d6PFN；\u5426\u5219\u904d\u5386\u56db\u7ea7\u9875\u8868<\/p>\n

\u5f53hello\u9996\u6b21\u8bbf\u95ee0x4010f0（_start\u51fd\u6570\u5165\u53e3）\u65f6，TLB\u672a\u547d\u4e2d，\u97004\u6b21\u5185\u5b58\u8bbf\u95ee\u5b8c\u6210\u9875\u8868\u904d\u5386\u3002\u540e\u7eed\u8bbf\u95ee\u540c\u4e00\u9875\u65f6，TLB\u547d\u4e2d，\u8f6c\u6362\u5ef6\u8fdf\u964d\u81f31~2\u5468\u671f<\/p>\n

7.5 \u4e09\u7ea7Cache\u652f\u6301\u4e0b\u7684\u7269\u7406\u5185\u5b58\u8bbf\u95ee<\/h3>\n

\u7269\u7406\u5185\u5b58\u8bbf\u95ee\u901a\u8fc7\u4e09\u7ea7Cache\u4f18\u5316\u6027\u80fd：<\/p>\n

\u7f13\u5b58\u5c42\u7ea7：L1（\u6307\u4ee4\/\u6570\u636e\u5206\u79bb）\u3001L2（\u7edf\u4e00）\u3001L3（\u5171\u4eab）\u7f13\u5b58，\u9010\u7ea7\u5bb9\u91cf\u589e\u5927\u3001\u901f\u5ea6\u964d\u4f4e\u3002<\/p>\n

\u7f13\u5b58\u884c\u5339\u914d：\u7269\u7406\u5730\u5740\u88ab\u5212\u5206\u4e3a\u6807\u8bb0（Tag）\u3001\u7ec4\u7d22\u5f15（Set Index）\u548c\u5757\u504f\u79fb（Offset），\u901a\u8fc7\u7ec4\u76f8\u8054\u6620\u5c04\u5b9a\u4f4d\u7f13\u5b58\u884c\u3002<\/p>\n

\u66ff\u6362\u7b56\u7565：LRU（\u6700\u8fd1\u6700\u5c11\u4f7f\u7528）\u7b97\u6cd5\u6dd8\u6c70\u65e7\u6570\u636e\u3002<\/p>\n

hello\u8bbf\u95ee\u7269\u7406\u5730\u57400x2000038\u65f6，\u82e5L1 Cache\u547d\u4e2d（Tag\u5339\u914d），1~2\u5468\u671f\u5b8c\u6210\u8bfb\u53d6；\u5426\u5219\u89e6\u53d1L2\/L3\u8bbf\u95ee（\u7ea610~40\u5468\u671f）\u6216\u5185\u5b58\u52a0\u8f7d（\u7ea6100\u5468\u671f）\u3002<\/p>\n

7.6 hello\u8fdb\u7a0bfork\u65f6\u7684\u5185\u5b58\u6620\u5c04<\/h3>\n

fork\u521b\u5efa\u5b50\u8fdb\u7a0b\u65f6\u91c7\u7528\u5199\u65f6\u590d\u5236（Copy-on-Write）\u673a\u5236：<\/p>\n

\u5171\u4eab\u7236\u8fdb\u7a0b\u9875\u8868：\u5b50\u8fdb\u7a0b\u521d\u59cb\u5171\u4eab\u7236\u8fdb\u7a0b\u7684\u7269\u7406\u9875，\u9875\u8868\u9879\u6807\u8bb0\u4e3a\u53ea\u8bfb\u3002<\/p>\n

\u5199\u65f6\u590d\u5236：\u5f53\u4efb\u4e00\u8fdb\u7a0b\u5c1d\u8bd5\u4fee\u6539\u5171\u4eab\u9875\u65f6，\u89e6\u53d1\u9875\u9519\u8bef，\u5185\u6838\u5206\u914d\u65b0\u7269\u7406\u9875\u5e76\u590d\u5236\u5185\u5bb9\u3002<\/p>\n

\u82e5\u7236\u8fdb\u7a0b\u4fee\u6539hello\u7684\u5168\u5c40\u53d8\u91cf，\u5b50\u8fdb\u7a0b\u5c06\u83b7\u5f97\u72ec\u7acb\u7684\u7269\u7406\u9875\u526f\u672c，\u4fdd\u8bc1\u8fdb\u7a0b\u9694\u79bb\u6027\u3002<\/p>\n

7.7 hello\u8fdb\u7a0bexecve\u65f6\u7684\u5185\u5b58\u6620\u5c04<\/h3>\n

execve\u52a0\u8f7dhello\u7a0b\u5e8f\u65f6\u91cd\u5efa\u5185\u5b58\u6620\u5c04：<\/p>\n

\u91ca\u653e\u65e7\u5730\u5740\u7a7a\u95f4：\u6e05\u9664\u539f\u8fdb\u7a0b\u7684\u4ee3\u7801\u3001\u6570\u636e\u6bb5\u548c\u5806\u6808\u3002<\/p>\n

\u52a0\u8f7d\u65b0\u7a0b\u5e8f：\u5c06hello\u7684\u4ee3\u7801\u6bb5\u6620\u5c04\u52300x8048000，\u6570\u636e\u6bb5\u52300x8050000，\u5e76\u521d\u59cb\u5316\u5806\u6808\u548c\u5806\u3002<\/p>\n

\u52a8\u6001\u94fe\u63a5：\u82e5\u4f7f\u7528\u5171\u4eab\u5e93（\u5982libc.so），\u901a\u8fc7\u52a8\u6001\u94fe\u63a5\u5668\u6620\u5c04\u5230\u8fdb\u7a0b\u7a7a\u95f4\u3002<\/p>\n

execve\u540e，hello\u7684.text\u6bb5\u6620\u5c04\u52300x4010f0（\u53ef\u6267\u884c\u4ee3\u7801），.rodata\u6bb5\u52300x402000（\u53ea\u8bfb\u5b57\u7b26\u4e32），\u6743\u9650\u4e3aR-X\u548cR–\u3002<\/p>\n

7.8 \u7f3a\u9875\u6545\u969c\u4e0e\u7f3a\u9875\u4e2d\u65ad\u5904\u7406<\/h3>\n

\u89e6\u53d1\u6761\u4ef6：\u8bbf\u95ee\u672a\u52a0\u8f7d\u7684\u865a\u62df\u9875（\u9875\u8868\u9879\u65e0\u6548）\u6216\u5199\u53ea\u8bfb\u9875（\u5982COW\u573a\u666f）\u3002<\/p>\n

\u4e2d\u65ad\u5904\u7406：\u68c0\u67e5\u865a\u62df\u5730\u5740\u5408\u6cd5\u6027\u3002<\/p>\n

\u5206\u914d\u7269\u7406\u9875（\u6216\u4ece\u78c1\u76d8\u6362\u5165）\u3002<\/p>\n

\u66f4\u65b0\u9875\u8868\u9879\u5e76\u91cd\u65b0\u6267\u884c\u6307\u4ee4\u3002<\/p>\n

hello\u9996\u6b21\u8bbf\u95ee\u5806\u5185\u5b58\u65f6\u89e6\u53d1\u7f3a\u9875，\u5185\u6838\u5206\u914d\u96f6\u9875（\u5168\u96f6\u586b\u5145\u7684\u7269\u7406\u9875），\u907f\u514d\u672a\u521d\u59cb\u5316\u6570\u636e\u9519\u8bef\u3002<\/p>\n

7.9\u52a8\u6001\u5b58\u50a8\u5206\u914d\u7ba1\u7406<\/h3>\n

printf\u8c03\u7528malloc\u65f6，\u52a8\u6001\u5185\u5b58\u7ba1\u7406\u7b56\u7565\u5982\u4e0b：<\/p>\n

\u9690\u5f0f\u7a7a\u95f2\u94fe\u8868：\u901a\u8fc7\u5757\u5934\u90e8\u7684\u5927\u5c0f\u5b57\u6bb5\u904d\u5386\u7a7a\u95f2\u5757，\u5408\u5e76\u76f8\u90bb\u7a7a\u95f2\u5757\u51cf\u5c11\u788e\u7247\u3002<\/p>\n

\u663e\u5f0f\u7a7a\u95f2\u94fe\u8868：\u7ef4\u62a4\u7a7a\u95f2\u5757\u94fe\u8868，\u52a0\u901f\u5206\u914d\u3002<\/p>\n

\u4f19\u4f34\u7cfb\u7edf：\u63092\u7684\u5e42\u5212\u5206\u5757，\u51cf\u5c11\u5916\u90e8\u788e\u7247\u4f46\u53ef\u80fd\u4ea7\u751f\u5185\u90e8\u788e\u7247\u3002<\/p>\n

glibc\u7684malloc\u4e3ahello\u5206\u914d\u5c0f\u5185\u5b58\u65f6，\u4f18\u5148\u4ece\u7ebf\u7a0b\u672c\u5730\u7f13\u5b58（tcache）\u83b7\u53d6，\u51cf\u5c11\u9501\u7ade\u4e89；\u5927\u5185\u5b58\u5219\u901a\u8fc7mmap\u7cfb\u7edf\u8c03\u7528\u76f4\u63a5\u6620\u5c04\u3002<\/p>\n

7.10\u672c\u7ae0\u5c0f\u7ed3<\/h3>\n

\u672c\u7ae0\u7cfb\u7edf\u89e3\u6790\u4e86hello\u7a0b\u5e8f\u7684\u5b58\u50a8\u7ba1\u7406\u673a\u5236\u3002\u4ece\u903b\u8f91\u5730\u5740\u5230\u7269\u7406\u5730\u5740\u7684\u8f6c\u6362\u4f9d\u8d56\u6bb5\u5f0f\u4e0e\u9875\u5f0f\u7ba1\u7406，TLB\u548c\u56db\u7ea7\u9875\u8868\u4f18\u5316\u4e86\u6620\u5c04\u6548\u7387\u3002\u4e09\u7ea7Cache\u901a\u8fc7\u5c42\u7ea7\u7f13\u5b58\u964d\u4f4e\u5185\u5b58\u8bbf\u95ee\u5ef6\u8fdf\u3002\u8fdb\u7a0bfork\u65f6\u7684\u5199\u65f6\u590d\u5236\u4e0eexecve\u7684\u5185\u5b58\u91cd\u5efa\u673a\u5236，\u4fdd\u969c\u4e86\u8fdb\u7a0b\u7684\u9694\u79bb\u4e0e\u7075\u6d3b\u6027\u3002\u7f3a\u9875\u4e2d\u65ad\u5b9e\u73b0\u6309\u9700\u52a0\u8f7d，\u52a8\u6001\u5185\u5b58\u7ba1\u7406\u7b56\u7565（\u5982malloc）\u5e73\u8861\u4e86\u6548\u7387\u4e0e\u788e\u7247\u95ee\u9898\u3002\u5b58\u50a8\u7ba1\u7406\u662f\u64cd\u4f5c\u7cfb\u7edf\u8d44\u6e90\u8c03\u5ea6\u7684\u6838\u5fc3，\u652f\u6491\u4e86hello\u7a0b\u5e8f\u4ece\u5730\u5740\u62bd\u8c61\u5230\u7269\u7406\u6267\u884c\u7684\u5168\u6d41\u7a0b\u3002<\/p>\n<\/p>\n

\u7b2c8\u7ae0 hello\u7684IO\u7ba1\u7406<\/h2>\n

8.1 Linux\u7684IO\u8bbe\u5907\u7ba1\u7406\u65b9\u6cd5<\/h3>\n

Linux\u91c7\u7528\u7edf\u4e00\u7684\u201c\u4e00\u5207\u7686\u6587\u4ef6\u201d\u6a21\u578b\u7ba1\u7406IO\u8bbe\u5907：<\/p>\n

\u8bbe\u5907\u62bd\u8c61：\u6240\u6709\u786c\u4ef6\u8bbe\u5907（\u952e\u76d8\u3001\u663e\u793a\u5668\u3001\u78c1\u76d8\u7b49）\u88ab\u62bd\u8c61\u4e3a\u6587\u4ef6，\u4f4d\u4e8e\/dev\u76ee\u5f55\u4e0b，\u5982\/dev\/tty\u8868\u793a\u7ec8\u7aef\u8bbe\u5907\u3002<\/p>\n

\u8bbe\u5907\u5206\u7c7b：<\/p>\n

\u5b57\u7b26\u8bbe\u5907：\u4ee5\u5b57\u8282\u6d41\u5f62\u5f0f\u8bbf\u95ee（\u5982\u952e\u76d8\u3001\u4e32\u53e3），\u901a\u8fc7\u5b57\u7b26\u8bbe\u5907\u6587\u4ef6（\u5982\/dev\/input\/event0）\u64cd\u4f5c\u3002<\/p>\n

\u5757\u8bbe\u5907：\u4ee5\u56fa\u5b9a\u5927\u5c0f\u6570\u636e\u5757\u8bbf\u95ee（\u5982\u786c\u76d8\u3001SSD），\u901a\u8fc7\u5757\u8bbe\u5907\u6587\u4ef6（\u5982\/dev\/sda）\u64cd\u4f5c\u3002<\/p>\n

\u8bbe\u5907\u9a71\u52a8\u7ba1\u7406：\u5185\u6838\u901a\u8fc7\u8bbe\u5907\u9a71\u52a8\u7a0b\u5e8f\u4e0e\u786c\u4ef6\u4ea4\u4e92，\u7528\u6237\u7a0b\u5e8f\u901a\u8fc7\u6807\u51c6Unix IO\u63a5\u53e3（\u5982read\u3001write）\u8bbf\u95ee\u8bbe\u5907，\u65e0\u9700\u5173\u5fc3\u5e95\u5c42\u5b9e\u73b0\u3002<\/p>\n

hello\u901a\u8fc7printf\u8f93\u51fa\u5230\u7ec8\u7aef\u65f6，\u5b9e\u9645\u662f\u5411\u5b57\u7b26\u8bbe\u5907\u6587\u4ef6\/dev\/tty\u5199\u5165\u6570\u636e，\u7531\u663e\u793a\u9a71\u52a8\u5904\u7406；getchar\u5219\u4ece\u540c\u4e00\u8bbe\u5907\u8bfb\u53d6\u952e\u76d8\u8f93\u5165\u3002<\/p>\n

8.2 \u7b80\u8ff0Unix IO\u63a5\u53e3\u53ca\u5176\u51fd\u6570<\/h3>\n

Unix IO\u63a5\u53e3\u63d0\u4f9b\u4ee5\u4e0b\u6838\u5fc3\u7cfb\u7edf\u8c03\u7528：<\/p>\n

open：\u6253\u5f00\u8bbe\u5907\u6587\u4ef6（\u5982\/dev\/tty）\u00a0 \u8fd4\u56de\u6587\u4ef6\u63cf\u8ff0\u7b26（fd）\u3002<\/p>\n

read：\u4ecefd\u8bfb\u53d6\u6570\u636e（\u5982\u952e\u76d8\u8f93\u5165） \u51fd\u6570\u539f\u578b：ssize_t read(int fd, void *buf, size_t count)<\/p>\n

write：\u5411fd\u5199\u5165\u6570\u636e（\u5982\u5c4f\u5e55\u8f93\u51fa） \u51fd\u6570\u539f\u578b：ssize_t write(int fd, const void *buf, size_t count)<\/p>\n

close：\u5173\u95edfd，\u91ca\u653e\u8d44\u6e90<\/p>\n

ioctl：\u63a7\u5236\u8bbe\u5907\u53c2\u6570（\u5982\u8bbe\u7f6e\u7ec8\u7aef\u6a21\u5f0f）<\/p>\n

IO\u6a21\u5f0f：<\/p>\n

\u963b\u585eIO：\u9ed8\u8ba4\u6a21\u5f0f，\u82e5\u8bbe\u5907\u65e0\u6570\u636e，\u8fdb\u7a0b\u6302\u8d77\u7b49\u5f85（\u5982getchar\u7b49\u5f85\u952e\u76d8\u8f93\u5165）\u3002<\/p>\n

\u975e\u963b\u585eIO：\u901a\u8fc7O_NONBLOCK\u6807\u5fd7\u8bbe\u7f6e，\u7acb\u5373\u8fd4\u56de\u9519\u8bef\u7801EAGAIN\u3002<\/p>\n

\u5f02\u6b65IO：\u901a\u8fc7\u4fe1\u53f7\u6216\u56de\u8c03\u901a\u77e5\u6570\u636e\u5c31\u7eea（\u5982aio_read）\u3002<\/p>\n

8.3 printf\u7684\u5b9e\u73b0\u5206\u6790<\/h3>\n

1.\u683c\u5f0f\u5316\u5b57\u7b26\u4e32\u5904\u7406：\u8c03\u7528vsprintf\u5c06\u683c\u5f0f\u5b57\u7b26\u4e32\u548c\u53c2\u6570\u8f6c\u6362\u4e3a\u683c\u5f0f\u5316\u540e\u7684\u5b57\u7b26\u4e32（\u5982"Hello \u5b66\u53f7 \u59d3\u540d \u624b\u673a\u53f7 1"），\u5b58\u5165\u7528\u6237\u6001\u7f13\u51b2\u533a\u3002<\/p>\n

2.\u7cfb\u7edf\u8c03\u7528\u5199\u5165：\u8c03\u7528write\u7cfb\u7edf\u8c03\u7528（\u51fd\u6570\u53f7SYS_write），\u89e6\u53d1\u8f6f\u4e2d\u65ad（\u5982syscall\u6307\u4ee4\u6216int 0x80），\u5207\u6362\u5230\u5185\u6838\u6001\u3002\u5185\u6838\u901a\u8fc7\u7ec8\u7aef\u8bbe\u5907\u9a71\u52a8\u5c06\u5b57\u7b26\u4e32\u5199\u5165\u663e\u793a\u7f13\u51b2\u533a（vram）\u3002<\/p>\n

3.\u663e\u793a\u9a71\u52a8\u5904\u7406：\u5b57\u6a21\u5e93\u6620\u5c04\u5c06ASCII\u5b57\u7b26\u8f6c\u6362\u4e3a\u50cf\u7d20\u70b9\u9635（16\u00d716\u70b9\u9635），vram\u66f4\u65b0\u5c06\u50cf\u7d20RGB\u503c\u5199\u5165\u663e\u5b58\u5bf9\u5e94\u4f4d\u7f6e（\u6bcf\u4e2a\u50cf\u7d20\u53604\u5b57\u8282，\u683c\u5f0f\u4e3aARGB）\u3002<\/p>\n

\u5c4f\u5e55\u5237\u65b0，\u663e\u793a\u63a7\u5236\u5668\u6309\u5237\u65b0\u7387（\u598260Hz）\u9010\u884c\u8bfb\u53d6vram，\u901a\u8fc7\u4fe1\u53f7\u7ebf\u8f93\u51fa\u5230\u663e\u793a\u5668\u3002<\/p>\n

8.4 getchar\u7684\u5b9e\u73b0\u5206\u6790<\/h3>\n

1.\u952e\u76d8\u4e2d\u65ad\u89e6\u53d1：\u7528\u6237\u6309\u4e0b\u6309\u952e\u65f6，\u952e\u76d8\u63a7\u5236\u5668\u53d1\u9001\u4e2d\u65ad\u8bf7\u6c42（IRQ1），CPU\u8c03\u7528\u952e\u76d8\u4e2d\u65ad\u5904\u7406\u7a0b\u5e8f（ISR）\u3002<\/p>\n

2.\u626b\u63cf\u7801\u8f6c\u6362：ISR\u8bfb\u53d6\u952e\u76d8\u626b\u63cf\u7801（\u5982\u56de\u8f66\u952e\u4e3a0x1C），\u8f6c\u6362\u4e3aASCII\u7801（\u5982'\\\\n'），\u5b58\u5165\u5185\u6838\u7f13\u51b2\u533atty_read_buf\u3002<\/p>\n

3.\u7cfb\u7edf\u8c03\u7528\u8bfb\u53d6：getchar\u8c03\u7528read\u7cfb\u7edf\u8c03\u7528（fd=0），\u4ece\u7f13\u51b2\u533a\u8bfb\u53d6ASCII\u7801，\u82e5\u7f13\u51b2\u533a\u4e3a\u7a7a\u5219\u963b\u585e\u7b49\u5f85\u3002\u9047\u5230\u6362\u884c\u7b26（'\\\\n'）\u65f6，read\u8fd4\u56de\u7f13\u51b2\u533a\u5185\u5bb9，\u7528\u6237\u7a0b\u5e8f\u7ee7\u7eed\u6267\u884c\u3002<\/p>\n

8.5\u672c\u7ae0\u5c0f\u7ed3<\/h3>\n

\u672c\u7ae0\u63a2\u8ba8\u4e86hello\u7a0b\u5e8f\u7684IO\u7ba1\u7406\u673a\u5236\u3002Linux\u901a\u8fc7\u201c\u4e00\u5207\u7686\u6587\u4ef6\u201d\u6a21\u578b\u5c06\u786c\u4ef6\u8bbe\u5907\u62bd\u8c61\u4e3a\u5b57\u7b26\u8bbe\u5907（\u5982\u7ec8\u7aef\/dev\/tty）\u6216\u5757\u8bbe\u5907，\u7528\u6237\u7a0b\u5e8f\u901a\u8fc7\u6807\u51c6Unix\u63a5\u53e3（\u5982read\u3001write）\u5b9e\u73b0\u8bbe\u5907\u8bbf\u95ee\u3002printf\u7684\u6267\u884c\u5206\u4e3a\u4e09\u6b65：vsprintf\u683c\u5f0f\u5316\u5b57\u7b26\u4e32\u751f\u6210\u8f93\u51fa\u5185\u5bb9，write\u7cfb\u7edf\u8c03\u7528\u5c06\u6570\u636e\u5199\u5165\u663e\u5b58（vram），\u663e\u793a\u9a71\u52a8\u5c06ASCII\u5b57\u7b26\u8f6c\u6362\u4e3a\u50cf\u7d20\u77e9\u9635\u5e76\u5237\u65b0\u5c4f\u5e55\u3002getchar\u4f9d\u8d56\u952e\u76d8\u4e2d\u65ad\u673a\u5236，\u4e2d\u65ad\u5904\u7406\u7a0b\u5e8f\u5c06\u626b\u63cf\u7801\u8f6c\u4e3aASCII\u7801\u5b58\u5165\u5185\u6838\u7f13\u51b2\u533a，read\u7cfb\u7edf\u8c03\u7528\u963b\u585e\u8bfb\u53d6\u76f4\u81f3\u56de\u8f66\u89e6\u53d1\u8fd4\u56de\u3002<\/p>\n

\n

\n

\n

\n

\n

\u7ed3\u8bba<\/h2>\n

Hello\u7a0b\u5e8f\u7684\u751f\u547d\u5468\u671f\u5b8c\u6574\u4f53\u73b0\u4e86\u8ba1\u7b97\u673a\u7cfb\u7edf\u7684\u6838\u5fc3\u8bbe\u8ba1\u7406\u5ff5\u3002\u4ece\u4ee3\u7801（Program）\u5230\u8fdb\u7a0b（Process）\u7684P2P\u6d41\u7a0b\u4e2d，\u7f16\u8bd1\u7cfb\u7edf\u901a\u8fc7\u9884\u5904\u7406\u3001\u7f16\u8bd1\u3001\u6c47\u7f16\u3001\u94fe\u63a5\u5c06\u9ad8\u7ea7\u8bed\u8a00\u8f6c\u6362\u4e3a\u53ef\u6267\u884c\u6587\u4ef6；\u64cd\u4f5c\u7cfb\u7edf\u901a\u8fc7\u8fdb\u7a0b\u7ba1\u7406（fork\u3001execve）\u548c\u5b58\u50a8\u7ba1\u7406（\u6bb5\u9875\u5f0f\u8f6c\u6362\u3001TLB\u3001Cache）\u4e3a\u7a0b\u5e8f\u63d0\u4f9b\u6267\u884c\u73af\u5883；\u786c\u4ef6\u4e0e\u5185\u6838\u534f\u4f5c\u5b8c\u6210\u6307\u4ee4\u6267\u884c\u3001\u5730\u5740\u8f6c\u6362\u548cIO\u64cd\u4f5c\u3002<\/p>\n

\u901a\u8fc7\u672c\u9879\u76ee，\u6211\u6df1\u5207\u611f\u609f\u5230：<\/p>\n

\u5206\u5c42\u62bd\u8c61：\u8ba1\u7b97\u673a\u7cfb\u7edf\u901a\u8fc7\u7f16\u8bd1\u94fe\u3001\u64cd\u4f5c\u7cfb\u7edf\u548c\u786c\u4ef6\u7684\u5206\u5c42\u62bd\u8c61，\u5b9e\u73b0\u4e86\u4ece\u9ad8\u7ea7\u8bed\u8a00\u5230\u7269\u7406\u786c\u4ef6\u7684\u65e0\u7f1d\u8854\u63a5，\u6781\u5927\u63d0\u5347\u4e86\u5f00\u53d1\u6548\u7387\u4e0e\u7cfb\u7edf\u53ef\u9760\u6027\u3002<\/p>\n

\u52a8\u6001\u6027\u4e0e\u7075\u6d3b\u6027：\u52a8\u6001\u94fe\u63a5\u3001\u5199\u65f6\u590d\u5236\u548c\u6309\u9700\u5206\u9875\u7b49\u673a\u5236，\u5e73\u8861\u4e86\u8d44\u6e90\u5229\u7528\u7387\u4e0e\u6027\u80fd，\u5c55\u73b0\u4e86\u7cfb\u7edf\u8bbe\u8ba1\u7684\u7cbe\u5de7\u3002<\/p>\n

\u4f18\u5316\u7a7a\u95f4：\u5728\u5de5\u5177\u94fe\u914d\u7f6e（\u5982\u7f16\u8bd1\u5668\u4f18\u5316\u9009\u9879）\u3001\u5185\u5b58\u7ba1\u7406（\u5982\u51cf\u5c11\u7f3a\u9875\u4e2d\u65ad）\u548cIO\u6548\u7387（\u5982\u7f13\u51b2\u7b56\u7565）\u7b49\u65b9\u9762\u4ecd\u6709\u4f18\u5316\u6f5c\u529b\u3002<\/p>\n

\u672c\u9879\u76ee\u4e0d\u4ec5\u5de9\u56fa\u4e86\u8ba1\u7b97\u673a\u7cfb\u7edf\u6838\u5fc3\u77e5\u8bc6，\u66f4\u542f\u53d1\u4e86\u5bf9\u7cfb\u7edf\u8bbe\u8ba1\u4e0e\u5b9e\u73b0\u7684\u521b\u65b0\u601d\u8003\u3002<\/p>\n

\n<\/p>\n

\u9644\u4ef6<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n
\n

\u6587\u4ef6\u540d<\/p>\n<\/td>\n

\n

\u4f5c\u7528<\/p>\n<\/td>\n<\/tr>\n

\n

hello.c<\/p>\n<\/td>\n

<\/td>\n<\/tr>\n
\n

hello.i<\/p>\n<\/td>\n

\n

\u9884\u5904\u7406\u540e\u7684\u4ee3\u7801\u6587\u4ef6，\u5c55\u5f00\u6240\u6709\u5b8f\u3001\u5934\u6587\u4ef6，\u5e76\u5220\u9664\u6ce8\u91ca\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

hello.s<\/p>\n<\/td>\n

\n

\u6c47\u7f16\u4ee3\u7801\u6587\u4ef6，\u5305\u542bx86-64\u6c47\u7f16\u6307\u4ee4\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

hello.o<\/p>\n<\/td>\n

\n

\u53ef\u91cd\u5b9a\u4f4d\u76ee\u6807\u6587\u4ef6（ELF\u683c\u5f0f），\u5c1a\u672a\u94fe\u63a5\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

hello<\/p>\n<\/td>\n

\n

\u6700\u7ec8\u7684\u53ef\u6267\u884c\u6587\u4ef6，\u5305\u542b\u52a8\u6001\u94fe\u63a5\u5e93（\u5982libc）\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

hello_o_dump.txt<\/p>\n<\/td>\n

\n

hello.o\u7684\u53cd\u6c47\u7f16\u8f93\u51fa（objdump -d），<\/p>\n

\u7528\u4e8e\u5206\u6790\u673a\u5668\u7801\u548c\u6c47\u7f16\u6307\u4ee4\u7684\u5bf9\u5e94\u5173\u7cfb\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

hello_o_elf.txt<\/p>\n<\/td>\n

\n

hello.o\u7684ELF\u7ed3\u6784\u5206\u6790（readelf），<\/p>\n

\u67e5\u770b\u8282\u5934\u3001\u7b26\u53f7\u8868\u3001\u91cd\u5b9a\u4f4d\u4fe1\u606f\u7b49\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

hello_dump.txt<\/p>\n<\/td>\n

\n

hello\u7684\u53cd\u6c47\u7f16\u8f93\u51fa（objdump -d），<\/p>\n

\u5206\u6790\u53ef\u6267\u884c\u6587\u4ef6\u7684\u673a\u5668\u7801\u548c\u8fd0\u884c\u65f6\u884c\u4e3a\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

hello_elf.txt<\/p>\n<\/td>\n

\n

hello\u7684ELF\u7ed3\u6784\u5206\u6790（readelf），<\/p>\n

\u67e5\u770b\u7a0b\u5e8f\u5165\u53e3\u3001\u52a8\u6001\u94fe\u63a5\u4fe1\u606f\u7b49\u3002<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n\n
\n

\u539f\u59cb\u7684C\u8bed\u8a00\u6e90\u4ee3\u7801\u6587\u4ef6<\/p>\n<\/td>\n<\/tr>\n

\n

\u9884\u5904\u7406\u540e\u7684\u4ee3\u7801\u6587\u4ef6，\u5c55\u5f00\u6240\u6709\u5b8f\u3001\u5934\u6587\u4ef6，\u5e76\u5220\u9664\u6ce8\u91ca\u3002<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\n<\/p>\n

\u53c2\u8003\u6587\u732e<\/h2>\n

[1] \u00a0Randal E. Bryant\u00a0,David O'Hallaron. \u6df1\u5165\u7406\u89e3\u8ba1\u7b97\u673a\u7cfb\u7edf（\u7b2c3\u7248）, \u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e,2016.11<\/p>\n

[2] Alfred V. Aho,Monica S.Lam,Ravi Sethi,Jeffrey D. Ullman. \u7f16\u8bd1\u539f\u7406, \u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e,2008.12<\/p>\n

[3] Andrew S. Tanenbaum. \u73b0\u4ee3\u64cd\u4f5c\u7cfb\u7edf（\u7b2c3\u7248）,\u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e,2009.7<\/p>\n","protected":false},"excerpt":{"rendered":"

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