{"id":1316,"date":"2016-09-20T05:30:06","date_gmt":"2016-09-20T05:30:06","guid":{"rendered":"http:\/\/www.inforsec.org\/wp\/?p=1316"},"modified":"2016-09-20T05:30:06","modified_gmt":"2016-09-20T05:30:06","slug":"%e4%ba%91%e8%ae%a1%e7%ae%97%e4%b8%ad%e8%b7%a8%e8%99%9a%e6%8b%9f%e6%9c%ba%e7%9a%84row-hammer%e6%94%bb%e5%87%bb%e5%92%8c%e6%9d%83%e9%99%90%e6%8f%90%e5%8d%87","status":"publish","type":"post","link":"http:\/\/202.112.238.40\/wp\/?p=1316","title":{"rendered":"\u4e91\u8ba1\u7b97\u4e2d\u8de8\u865a\u62df\u673a\u7684Row Hammer\u653b\u51fb\u548c\u6743\u9650\u63d0\u5347"},"content":{"rendered":"

\u4e91\u8ba1\u7b97\u4e2d\u8de8\u865a\u62df\u673a\u7684Row Hammer\u653b\u51fb\u548c\u6743\u9650\u63d0\u5347<\/strong><\/h2>\n

One Bit Flips, One Cloud Flops: Cross-VM Row Hammer Attacks and Privilege Escalation<\/h2>\n

\u4f5c\u8005\uff1aYuan Xiao, Xiaokuan Zhang, Yinqian Zhang, Mircea-Radu Teodorescu\uff0cDepartment of Computer Science and Engineering\uff0cThe Ohio State University<\/p>\n

Row hammer\u653b\u51fb\u662f\u4e00\u79cd\u9488\u5bf9\u52a8\u6001\u968f\u673a\u5b58\u53d6\u5185\u5b58\uff08DRAM\uff09\u7684\u653b\u51fb\u3002\u5b83\u5229\u7528\u9ad8\u5bc6\u5ea6\u5185\u5b58\u4e2d\u76f8\u90bb\u5b58\u50a8\u5355\u5143\u76f8\u4e92\u95f4\u7684\u7535\u78c1\u4f5c\u7528\u6765\u5f15\u53d1\u9519\u8bef\u3002\u901a\u8fc7\u5728\u4e00\u5b9a\u6a21\u5f0f\u4e0b\u7684\u9ad8\u9891\u7387\u53cd\u590d\u5185\u5b58\u8bbf\u95ee\uff0c\u653b\u51fb\u8005\u53ef\u4ee5\u5728\u5176\u539f\u672c\u65e0\u6743\u8bbf\u95ee\u7684\u5185\u5b58\u533a\u57df\u5f15\u53d1\u5b58\u50a8\u503c\u7684\u53d8\u5316\u3002\u672c\u6587\u4e2d\uff0c\u6211\u4eec\u5728\u8de8\u865a\u62df\u673a\u7684\u73af\u5883\u4e2d\u5229\u7528\u4e86\u8fd9\u79cd\u653b\u51fb\uff0c\u6253\u7834\u4e86\u865a\u62df\u673a\u4e4b\u95f4\u7684\u9694\u79bb\u4fdd\u62a4\u3002\u4e3a\u4e86\u8ba9row hammer\u653b\u51fb\u7684\u53ef\u9760\u6027\u66f4\u9ad8\uff0c\u6211\u4eec\u7528\u4e00\u79cd\u65b0\u7684\u65b9\u6cd5\u5728\u8fd0\u884c\u65f6\u53cd\u5411\u7834\u89e3\u7269\u7406\u5730\u5740\u5728\u5185\u5b58\u786c\u4ef6\u4e0a\u7684\u5206\u914d\u8bbe\u7f6e\uff0c\u5e76\u4ee5\u6b64\u4e3a\u57fa\u7840\u5b9e\u73b0\u4e86double-sided row hammer\u653b\u51fb\u3002\u5728\u8fd9\u79cd\u66f4\u5f3a\u529b\u7684row hammer\u653b\u51fb\u7684\u5e2e\u52a9\u4e0b\uff0c\u6211\u4eec\u63d0\u51fa\u4e00\u79cd\u521b\u65b0\u7684\u65b9\u6cd5\u7834\u89e3\u4e86Xen\u00a0PV\uff08Para-Virtualization\uff09\u7684\u5185\u5b58\u9694\u79bb\uff0c\u4f7f\u5f97\u4e00\u4e2a\u666e\u901a\u7684\u865a\u62df\u673a\u80fd\u591f\u8bfb\u5199\u6240\u5728\u7269\u7406\u673a\u4e0a\u7684\u4efb\u610f\u5185\u5b58\u4f4d\u7f6e\u3002\u540c\u65f6\uff0c\u6211\u4eec\u7684\u7814\u7a76\u4e5f\u63d0\u51fa\u4e86\u5728\u4f7f\u7528\u4e86Xen PV\u7684\u73b0\u4ee3\u516c\u5171\u4e91\u8bbe\u65bd\u4e2d\u8fdb\u884c\u653b\u51fb\u7684\u53ef\u884c\u6027\u3002\u56e0\u6b64\u6211\u4eec\u6240\u5c55\u793a\u7684\u653b\u51fb\u662f\u6709\u5b9e\u9645\u5a01\u80c1\u6027\u7684\u3002<\/p>\n

<\/p>\n

\u4e00\u3001\u7b80\u4ecb<\/strong><\/h3>\n

\u8f6f\u4ef6\u7cfb\u7edf\u7684\u5b89\u5168\u662f\u5efa\u7acb\u5728\u6b63\u786e\u6267\u884c\u7684\u786c\u4ef6\uff0f\u8f6f\u4ef6\u534f\u8bae\u7684\u57fa\u7840\u4e0a\u7684\u3002\u8fdd\u53cd\u8fd9\u4e9b\u534f\u8bae\u4f1a\u5e26\u6765\u4e25\u91cd\u7684\u5b89\u5168\u6f0f\u6d1e\u3002\u4f8b\u5982\u64cd\u4f5c\u7cfb\u7edf\u7684\u5b89\u5168\u5efa\u7acb\u5728\u5185\u5b58\u4e2d\u7684\u6570\u636e\u548c\u4ee3\u7801\u65e0\u6cd5\u5728\u7f3a\u4e4f\u64cd\u4f5c\u7cfb\u7edf\u6388\u6743\u7684\u60c5\u51b5\u4e0b\u88ab\u4fee\u6539\u7684\u5047\u8bbe\u4e0a\u3002\u7136\u800c\uff0c\u8fd1\u6765\u51fa\u73b0\u7684row hammer\u653b\u51fb\u5374\u80fd\u7834\u574f\u8fd9\u79cd\u5047\u8bbe\uff0c\u5e76\u5e26\u6765\u4e00\u7cfb\u5217\u5b89\u5168\u95ee\u9898\u3002\u8fd9\u79cd\u653b\u51fb\u53ef\u4ee5\u5728\u4e0d\u8bbf\u95ee\u76ee\u6807\u5185\u5b58\u533a\u57df\u7684\u524d\u63d0\u4e0b\u4f7f\u5176\u4ea7\u751f\u6570\u636e\u9519\u8bef\u3002<\/p>\n

Row \u00a0hammer\u653b\u51fb\u5229\u7528\u4e86\u5185\u5b58\u8bbe\u8ba1\u4e2d\u7684\u7f3a\u9677\u3002\u73b0\u4ee3\u5927\u5bb9\u91cf\u5185\u5b58\u6709\u7740\u5f88\u9ad8\u7684\u5185\u5b58\u5355\u5143\u5bc6\u5ea6\u3002\u8fd9\u4f7f\u5f97\u5355\u5143\u95f4\u7684\u76f8\u4e92\u7535\u78c1\u4f5c\u7528\u53d8\u5f97\u66f4\u4e3a\u663e\u8457\u3002\u7535\u78c1\u5f71\u54cd\u4f1a\u52a0\u901f\u7535\u5bb9\u7535\u538b\u7684\u53d8\u5316\uff0c\u5e26\u6765\u6f5c\u5728\u7684\u6570\u636e\u4e22\u5931\u5a01\u80c1\u3002\u8fd9\u79cd\u88ab\u79f0\u4f5c\u201cDisturbance Error\u201d\u7684\u6f0f\u6d1e\u591a\u5e74\u524d\u5c31\u5df2\u88ab\u53d1\u73b0\uff0c\u4f46\u662f\u5b83\u76f4\u5230\u6700\u8fd1\u624d\u88ab\u53d1\u73b0\u80fd\u591f\u88ab\u8f6f\u4ef6\u4eba\u4e3a\u89e6\u53d1\u3002\u5c24\u5176\u503c\u5f97\u6ce8\u610f\u7684\u662f\uff0c\u5feb\u901f\u5e76\u4e14\u91cd\u590d\u7684\u6fc0\u6d3b\u540c\u4e00\u4e2a\u5185\u5b58\u884c\uff08DRAM Row\uff09\u7684\u8bbf\u95ee\u6a21\u5f0f\u80fd\u5927\u5927\u63d0\u9ad8\u76f8\u90bb\u884c\u51fa\u73b0\u5e72\u6270\u9519\u8bef\u7684\u53ef\u80fd\u6027\u3002<\/p>\n

Row hammer\u6f0f\u6d1e\u88ab\u53d1\u73b0\u540e\u7684\u5f88\u77ed\u65f6\u95f4\u91cc\uff0c\u5229\u7528\u5b83\u8fdb\u884c\u7684\u5b89\u5168\u653b\u51fb\u5c31\u9646\u7eed\u51fa\u73b0\uff0c\u4f8b\u5982Google\u7684\u8f6f\u4ef6\u5de5\u7a0b\u5e08Seaborn\u5c55\u793a\u7684\u4e24\u79cd\u6743\u9650\u63d0\u5347\u653b\u51fb\uff08Google\u7684NaCl\u6c99\u76d2\u9003\u8131\u4ee5\u53ca\u5728Linux\u4e2d\u7684\u7528\u6237\u6001\u7a0b\u5e8f\u83b7\u53d6\u5185\u6838\u6001\u5185\u5b58\u8bbf\u95ee\u6743\u9650\uff09\u3002\u5176\u4ed6\u7684\u7814\u7a76\u4ee5\u7528\u9ad8\u7ea7\u7a0b\u5e8f\u8bbe\u8ba1\u8bed\u8a00\uff08\u5982JavaScript\uff09\u89e6\u53d1row hammer\u4e3a\u76ee\u6807\u3002\u8fd9\u6837\u4e00\u4e2a\u653b\u51fb\u8005\u5c31\u53ef\u4ee5\u901a\u8fc7\u7f51\u7edc\u4e2d\u6ce8\u5165\u7684\u6076\u610f\u4ee3\u7801\uff0c\u8fdc\u7a0b\u5730\u5f15\u53d1\u5185\u5b58\u9519\u8bef\u5e76\u5b9e\u73b0\u6743\u9650\u63d0\u5347\u3002<\/p>\n

\u5bf9\u4e8e\u670d\u52a1\u5668\u7aef\u7684\u653b\u51fb\u7684\u7814\u7a76\u8981\u8fdc\u5c11\u4e8e\u5bf9\u5ba2\u6237\u7aef\u653b\u51fb\u7684\u7814\u7a76\uff0c\u800crow hammer\u7684\u670d\u52a1\u5668\u7aef\u653b\u51fb\u5728\u591a\u7528\u6237\u7684\u4e91\u73af\u5883\u4e2d\u5c24\u5176\u503c\u5f97\u6ce8\u610f\u3002\u4e92\u4e0d\u4fe1\u4efb\u7684\u7528\u6237\u5728\u4e91\u4e2d\u53ef\u80fd\u5171\u4eab\u4e00\u53f0\u7269\u7406\u673a\u5668\uff0c\u5206\u4eab\u4e00\u4e9b\u786c\u4ef6\u8d44\u6e90\uff0c\u8fd9\u5c31\u5305\u62ec\u5185\u5b58\u3002\u5c3d\u7ba1\u670d\u52a1\u5668\u7ea7\u7684\u5904\u7406\u5668\u548c\u66f4\u6602\u8d35\u7684\u5185\u5b58\u5bf9\u4e8erow hammer\u7684\u9632\u5fa1\u66f4\u597d\uff0c\u7814\u7a76\u8868\u660e\u5373\u4f7f\u914d\u5907\u4e86\u5e26\u6709\u81ea\u52a8\u7ea0\u9519\uff08ECC\uff09\u529f\u80fd\u7684\u5185\u5b58\uff0c\u670d\u52a1\u5668\u4ecd\u7136\u53ef\u80fd\u53d7\u5230row hammer\u653b\u51fb\u7684\u5f71\u54cd\u3002<\/p>\n

\u5728\u6211\u4eec\u7684\u7814\u7a76\u4e2d\uff0c\u6211\u4eec\u7740\u91cd\u63a2\u7d22\u4e86row hammer\u653b\u51fb\u5728\u8de8\u865a\u62df\u673a\u73af\u5883\u4e2d\u7684\u5e94\u7528\uff0c\u5e76\u63d0\u51fa\u4e86\u5728\u4e91\u73af\u5883\u4e2d\u7684\u5a01\u80c1\u3002\u6211\u4eec\u7684\u76ee\u6807\u5e76\u4e0d\u662f\u653b\u51fb\u4e91\u670d\u52a1\u5668\uff0c\u8fdb\u800c\u63a2\u7a76\u5176\u5728\u8fd9\u79cd\u653b\u51fb\u9762\u524d\u6709\u591a\u8106\u5f31\uff0c\u800c\u662f\u63a2\u7d22\u5728\u786c\u4ef6\u5b58\u5728\u8fd9\u79cd\u9519\u8bef\u7684\u60c5\u51b5\u4e0b\uff0c\u4e91\u7cfb\u7edf\u4e2d\u57fa\u4e8e\u865a\u62df\u5316\u7684\u9694\u79bb\u662f\u5426\u53ef\u4ee5\u88ab\u7834\u574f\u3002<\/p>\n

\u4e8c\u3001\u5f3a\u5316\u7684row\u00a0hammer\u653b\u51fb<\/strong><\/h3>\n

\u5728\u672c\u6587\u4e2d\uff0c\u6211\u4eec\u63d0\u51fa\u4e86\u4e00\u79cd\u9ad8\u53ef\u9760\u5ea6\u4e14\u9ad8\u786e\u5b9a\u6027\u7684double-sided row hammer\u653b\u51fb\u3002 \u8fd9\u79cd\u653b\u51fb\u901a\u8fc7\u653b\u51fb\u76ee\u6807\u5185\u5b58\u884c\u7684\u4e24\u4e2a\u76f8\u90bb\u884c\u6765\u63d0\u9ad8\u653b\u51fb\u6548\u679c\u3002\u4f46\u662f\u8fd9\u5c31\u9700\u8981\u6211\u4eec\u4e86\u89e3\u7269\u7406\u5730\u5740\u662f\u5982\u4f55\u88ab\u5206\u914d\u5230\u5185\u5b58\u4e2d\u7684\uff0c\u6bd4\u5982\u7269\u7406\u5730\u5740\u4e2d\u7684\u54ea\u4e9b\u4f4d\u51b3\u5b9a\u4e86\u5185\u5b58\u7684channel\u3001bank\u3001row\u7b49\u3002\u8fd9\u4f7f\u5f97\u6211\u4eec\u53ef\u4ee5\u627e\u5230\u540c\u4e00\u4e2abank\u4e2d\u7684\u76f8\u90bb\u884c\uff08row\uff09\u3002\u7136\u800c\uff0cIntel\u62d2\u7edd\u516c\u5e03\u8fd9\u4e9b\u76f8\u5173\u4fe1\u606f\u3002\u53e6\u5916\uff0c\u5373\u4f7f\u4f7f\u7528\u540c\u6837\u7684\u5904\u7406\u5668\u548c\u540c\u6837\u7684\u5185\u5b58\u63a7\u5236\u5668\uff0c\u8fd9\u79cd\u5206\u914d\u65b9\u6cd5\u8fd8\u4f1a\u56e0\u4e3a\u5185\u5b58\uff08DRAM module\uff09\u7684\u533a\u522b\u800c\u4e0d\u540c\u3002<\/p>\n

\u4e3a\u4e86\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff0c\u6211\u4eec\u63d0\u51fa\u4e86\u4e00\u79cd\u7b97\u6cd5\u6765\u7834\u89e3\u7269\u7406\u5730\u5740\u7684\u52a8\u6001\u5206\u914d\u673a\u5236\u3002\u5185\u5b58\u82af\u7247\uff08chip\uff09\u4e2d\u7684\u6bcf\u4e2abank\u90fd\u6709\u4e00\u4e2a\u884c\u7f13\u51b2\u5668\uff08row buffer\uff09\u6765\u7f13\u5b58\u6700\u8fd1\u4f7f\u7528\u7684\u884c\u3002\u56e0\u6b64\uff0c\u5982\u679c\u6211\u4eec\u4ea4\u66ff\u8bbf\u95ee\u540c\u4e00\u4e2abank\u4e2d\u4e24\u4e2a\u4e0d\u540c\u7684\u884c\uff0c\u7531\u4e8e\u884c\u7f13\u51b2\u5668\u7684\u51b2\u7a81\uff0c\u6211\u4eec\u4f1a\u89c2\u5bdf\u5230\u4e00\u4e2a\u9ad8\u5ef6\u8fdf\u3002\u8fd9\u79cd\u8bbf\u95ee\u5ef6\u8fdf\u7684\u589e\u52a0\u5f62\u6210\u4e86\u4e00\u4e2a\u65f6\u5ef6\u901a\u9053\uff08timing channel\uff09\u3002\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u8fd9\u4e2a\u901a\u9053\u6765\u786e\u5b9a\u4e24\u4e2a\u7269\u7406\u5730\u5740\u662f\u5426\u88ab\u5206\u914d\u5230\u4e86\u540c\u4e00\u4e2abank\u7684\u4e0d\u540c\u884c\u3002\u901a\u8fc7\u4ea4\u66ff\u8bbf\u95ee\u4e24\u4e2a\u53ea\u6709\u7279\u5b9abit\u4e0d\u540c\u7684\u7269\u7406\u5730\u5740\uff0c\u6211\u4eec\u53ef\u4ee5\u5229\u7528\u5b83\u4eec\u662f\u5426\u5728\u540c\u4e00\u4e2abank\u7684\u4e0d\u540c\u884c\u4e2d\u3002\u57fa\u4e8e\u8fd9\u4e2a\u4e8b\u5b9e\uff0c\u6211\u4eec\u80fd\u591f\u63a8\u65ad\u51fa\u7269\u7406\u5730\u5740\u4e2d\u8fd9\u4e9b\u7279\u5b9abit\u7684\u529f\u80fd\uff0c \u4f8b\u5982\u662f\u5426\u51b3\u5b9a\u4e86bank\uff0crow\uff0c column\u7b49\u7b49\u3002<\/p>\n

\u5728\u8fd9\u4e2a\u65f6\u5ef6\u901a\u9053\u7684\u57fa\u7840\u4e0a\uff0c\u6211\u4eec\u63d0\u51fa\u4e86\u4e00\u79cd\u65b0\u7684\u57fa\u4e8e\u56fe\u6a21\u578b\u7684\u7b97\u6cd5\u6765\u7834\u89e3\u7269\u7406\u5730\u5740\u4e2d\u5b58\u5728\u7684XOR scheme\u3002\u4e3a\u4e86\u63d0\u9ad8\u5185\u5b58\u6027\u80fd\uff0c\u7269\u7406\u5730\u5740\u5206\u914d\u65f6\u4f1a\u5c06\u67d0\u4e9b\u51b3\u5b9a\u884c\u7684bit\u548c\u4e00\u4e9b\u5176\u4ed6bit\u8fdb\u884cXOR\u64cd\u4f5c\uff0c\u5e76\u7528\u8fd9\u4e2aXOR\u7684\u7ed3\u679c\u51b3\u5b9abank\u6216channel\u7b49\u3002\u5728\u6211\u4eec\u7684\u56fe\u6a21\u578b\u7b97\u6cd5\u4e2d\uff0c\u6bcf\u4e2a\u7269\u7406\u5730\u5740\u7684bit\u662f\u4e00\u4e2a\u8282\u70b9\uff0c\u901a\u8fc7\u5185\u5b58\u8bbf\u95ee\u5ef6\u8fdf\u6211\u4eec\u53ef\u4ee5\u5f97\u5230\u8282\u70b9\u95f4\u662f\u5426\u5b58\u5728XOR\u5173\u7cfb\u3002\u5982\u56fe1\u5c31\u662f\u4e00\u4e2a\u6211\u4eec\u7684\u56fe\u6a21\u578b\u7b97\u6cd5\u7684\u4f8b\u5b50\uff0c\u56fe\u4e2d\u4e0a\u534a\u90e8\u5206\u662f\u901a\u8fc7\u6d4b\u8bd5\u56db\u4e2abit\uff0815\uff0c16\uff0c18\u548c20\uff09\u6240\u5efa\u7acb\u7684\u56fe\u6a21\u578b\uff0c\u800c\u4e0b\u534a\u90e8\u5206\u662f\u5219\u662f\u5b83\u5bf9\u5e94\u7684XOR scheme\u00a0\u3002\u8fd9\u79cd\u7b97\u6cd5\u80fd\u5728\u4e00\u5230\u4e24\u5206\u949f\u5185\u5206\u6790\u51fa\u6211\u4eec\u7684\u5404\u4e2a\u6d4b\u8bd5\u673a\u5668\u7684\u5185\u5b58\u5206\u914d\u673a\u5236\u3002<\/p>\n

\"%e5%9b%be%e7%89%871\"<\/p>\n

\u56fe1 \u00a0\u57fa\u4e8e\u56fe\u6a21\u578b\u7684XOR scheme\u5206\u6790\u7b97\u6cd5<\/p>\n

\u5728\u6211\u4eec\u4e86\u89e3\u4e86\u7269\u7406\u5730\u5740\u7684\u5206\u914d\u673a\u5236\u540e\uff0c\u6211\u4eec\u5c31\u53ef\u4ee5\u4eceXen\u865a\u62df\u673a\u4e2d\u8fdb\u884cdouble-sided row hammer\u653b\u51fb\u3002\u6211\u4eec\u9996\u5148\u901a\u8fc7\u5b9e\u9a8c\u5206\u6790\u4e86\u54ea\u79cdrow hammer\u653b\u51fb\u7684\u65b9\u6cd5\u6700\u4e3a\u6709\u6548\uff08\u4f8b\u5982\u662f\u5426\u5f15\u5165mfence\u6307\u4ee4\uff09\u3002\u63a5\u7740\uff0c\u6211\u4eec\u901a\u8fc7\u4ece\u865a\u62df\u673a\u4e2d\u653b\u51fb\u6240\u6709\u53ef\u8bbf\u95ee\u5185\u5b58\u884c\u7684\u65b9\u6cd5\u627e\u5230\u8db3\u591f\u591a\u7684\u53ef\u653b\u51fbbit\u3002\u5b83\u4eec\u9700\u8981\u5728\u7279\u5b9a\u7684\u4f4d\u7f6e\uff0c\u5e76\u4e14\u53ef\u4ee5\u88ab\u91cd\u590d\u89e6\u53d1\u9519\u8bef\u3002\u7531\u4e8e\u6bcf\u4e2a\u865a\u62df\u673a\u4ec5\u4ec5\u88ab\u5206\u914d\u5230\u4e00\u5c0f\u90e8\u5206\u7269\u7406\u5185\u5b58\uff0c\u6211\u4eec\u4e5f\u8bbe\u8ba1\u4e86\u80fd\u591f\u6d4b\u8bd5\u591a\u4e8e\u521d\u59cb\u5206\u914d\u5185\u5b58\u7684\u65b9\u6cd5\u3002\u53e6\u5916\uff0c\u6211\u4eec\u8fd8\u8bbe\u8ba1\u4e86\u4e00\u4e2a\u5b89\u5168\u6a21\u5f0f\u6765\u51cf\u5c11\u53ef\u80fd\u4f7f\u5f97\u7cfb\u7edf\u5d29\u6e83\u7684\u5185\u5b58\u9519\u8bef\u3002<\/p>\n

\u4e09\u3001\u8de8\u865a\u62df\u673a\u73af\u5883\u4e0b\u7684row\u00a0hammer\u6743\u9650\u63d0\u5347<\/strong><\/h3>\n

\u4ee5\u5f80\u7684\u7814\u7a76\u90fd\u5bc4\u5e0c\u671b\u4e8e\u968f\u673a\u7684row hammer\u653b\u51fb\u80fd\u6070\u597d\u5728page table\u4e2d\u4ea7\u751f\u5185\u5b58\u9519\u8bef\u3002\u4e0d\u540c\u4e8e\u8fd9\u4e9b\u65b9\u6cd5\uff0c\u6211\u4eec\u8bbe\u8ba1\u4e86\u4e00\u79cd\u786e\u5b9a\u6027\u7684\u653b\u51fb\u6765\u83b7\u5f97\u8de8\u865a\u62df\u673a\u73af\u5883\u4e0b\u7684\u4efb\u610f\u5185\u5b58\u4f4d\u7f6e\u8bfb\u5199\u6743\u9650\u3002\u56fe2\u5c55\u793a\u4e86\u6574\u4e2a\u6743\u9650\u63d0\u5347\u653b\u51fb\u7684\u8fc7\u7a0b\u3002\u653b\u51fb\u8005\u662f\u4e00\u4e2a\u6ca1\u6709\u7279\u6b8a\u6743\u9650\u7684\u666e\u901a\u865a\u62df\u673a\uff0c\u5728\u53d1\u8d77\u653b\u51fb\u524d\u80fd\u5bf9\u81ea\u5df1\u7684\u5185\u5b58\u7a7a\u95f4\u8fdb\u884c\u8bfb\u5199\u64cd\u4f5c\u3002\u867d\u7136\u653b\u51fb\u8005\u6240\u62e5\u6709\u7684page table \u90fd\u88ab\u7ef4\u62a4\u5728\u653b\u51fb\u8005\u81ea\u5df1\u7684\u5185\u5b58\u7a7a\u95f4\u4e2d\uff0c\u653b\u51fb\u8005\u5e76\u4e0d\u80fd\u76f4\u63a5\u4fee\u6539page table\u3002\u6240\u6709\u7684\u4fee\u6539\u5fc5\u987b\u901a\u8fc7hypercall\u88abhypervisor\u5ba1\u6838 \u3002\u5728\u653b\u51fb\u524d\uff0c\u6211\u4eec\u901a\u8fc7row hammer\u653b\u51fb\u5728\u653b\u51fb\u8005\u7684\u5185\u5b58\u7a7a\u95f4\u91cc\u627e\u5230\u4e00\u4e2a\u53ef\u7528\u7684flippable bit\uff0c\u5e76\u4e14\u5b83\u5728page\u4e2d\u7684\u76f8\u5bf9\u4f4d\u7f6e\u9700\u8981\u6ee1\u8db3\u4e00\u5b9a\u6761\u4ef6\u3002\u6211\u4eec\u8981\u6c42\u5728\u5c06\u4e00\u4e2apage\uff084K\u5b57\u8282\uff09\u5747\u5206\u621064\u4e2a64 bit\u957f\u7684\u6bb5\u540e\uff0cflippable bit\u5728\u8fd9\u4e2a64 bit\u6bb5\u4e2d\u7684\u4f4d\u7f6e\u5bf9\u5e94\u4e00\u4e2apage table entry\u4e2d\u7684page frame number\u90e8\u5206\u3002<\/p>\n

\u9996\u5148\uff0c\u6211\u4eec\u627e\u5230\u4e00\u4e2alast-level page table\uff08\u5373PT\uff09\u548c\u4e00\u4e2a\u653b\u51fb\u8005\u63a7\u5236\u7684\u666e\u901apage\u3002\u8fd9\u4e24\u4e2apage\u7684\u7269\u7406\u5730\u5740\u53ea\u6709\u4e00\u4e2abit\u4e0d\u540c\uff0c\u5e76\u4e14\u8fd9\u4e2a\u4e0d\u540cbit\u7684\u4f4d\u7f6e\u5c31\u662fflippable bit\u6240\u5bf9\u5e94\u7684\u4f4d\u7f6e\u3002\u6211\u4eec\u5728\u8fd9\u4e2a\u666e\u901apage\u4e2d\u4f2a\u9020\u4e00\u4e2apage table\u3002\u8fd9\u4e2a\u4f2a\u9020\u7684page table\u4e2d\u7684entry\u6307\u5411\u4efb\u610f\u7684\u653b\u51fb\u8005\u60f3\u8981\u8bbf\u95ee\u7684\u5185\u5b58\u7269\u7406\u5730\u5740\uff0c\u4e0d\u8bba\u662f\u5426\u53d7\u653b\u51fb\u8005\u7684\u63a7\u5236\u3002<\/p>\n

\u7b2c\u4e8c\u6b65\u662f\u5c06\u9009\u5b9a\u7684PT\u6240\u5c5e\u7684second-level page table\uff08\u5373PMD\uff09\u590d\u5236\u5230\u5305\u542bflippable bit\u7684page\u4e2d\u3002\u7531\u4e8e\u6211\u4eec\u5e76\u6ca1\u6709\u4fee\u6539PMD\u548cPT\u7684\u5185\u5bb9\uff0c\u6211\u4eec\u53ef\u4ee5\u76f4\u63a5\u901a\u8fc7hypercall\u6765\u628a\u539f\u6765\u7684PMD\u66ff\u6362\u6210\u542b\u6709flippable bit\u7684page\u3002\u6211\u4eec\u79f0\u8fd9\u4e2a\u65b0\u7684PMD\u4e3ashadow PMD\u3002\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u4e4b\u524d\u6240\u9009\u5b9a\u7684PT\u5728PMD\u4e2d\u5bf9\u5e94\u7684entry\u5e94\u8be5\u5305\u542b\u8fd9\u4e2aflippable bit\u3002<\/p>\n

\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u901a\u8fc7row hammer\u6765\u5728shadow PMD\u7684\u8fd9\u4e2aentry\u4e2d\u4ea7\u751fbit flip\uff0c\u4f7f\u5f97\u539f\u672c\u6307\u5411PT\u7684\u6761\u76ee\u8f6c\u800c\u6307\u5411\u6211\u4eec\u4f2a\u9020\u7684PT\u3002\u6211\u4eec\u8bc1\u660e\u4e86\u8fd9\u4e2a\u653b\u51fb\u65b9\u6cd5\u53ef\u4ee5\u4f7f\u5f97\u4e00\u4e2aXen PV\u865a\u62df\u673a\u5bf9\u4e8e\u673a\u5668\u4e0a\u7684\u4efb\u610fpage\u62e5\u6709\u8bfb\u5199\u6743\u9650\u3002\u5e76\u4e14\u6b64\u65f6hypervisor\u548c\u653b\u51fb\u8005\u7684kernel\u4ecd\u7136\u8ba4\u4e3a\u8fd9\u4e2a\u4f2a\u9020\u7684PT\u662f\u4e00\u4e2a\u666e\u901apage\uff0c\u56e0\u6b64\u653b\u51fb\u8005\u4ecd\u7136\u53ef\u4ee5\u901a\u8fc7\u76f4\u63a5\u5199\u5165\u7684\u65b9\u5f0f\u6765\u4fee\u6539\u4f2a\u9020\u7684PT\u4e2d\u7684entry\u3002<\/p>\n

\"%e5%9b%be%e7%89%872\"<\/p>\n

\u56fe2 \u00a0\u9875\u9762\u8868\u66ff\u6362\u653b\u51fb\uff08Page\u00a0Table Replacement Attack\uff09<\/p>\n

\u53e6\u5916\uff0c\u6211\u4eec\u8fd8\u5c55\u793a\u4e86\u4e24\u4e2a\u57fa\u4e8e\u8fd9\u79cd\u653b\u51fb\u7684\u5b9e\u4f8b\u3002 \u4e00\u4e2a\u4f8b\u5b50\u662fHTTPS\u7f51\u7edc\u670d\u52a1\u5668\u4e2d\u7684\u79c1\u94a5\u7a83\u53d6\u3002\u6211\u4eec\u5229\u7528\u5bf9\u4efb\u610f\u7269\u7406\u5185\u5b58\u7684\u8bfb\u6743\u9650\u5224\u65ad\u67d0\u4e00\u5185\u5b58\u5730\u5740\u662f\u5426\u50a8\u5b58\u7684\u6570\u636e\u7ed3\u6784\u662f\u5426\u7b26\u5408\u4e00\u4e2a\u6709\u6548\u5bc6\u94a5\u7684\u7ed3\u6784\u3002<\/p>\n

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\u53c2\u8003\u6587\u732e\uff1a<\/strong><\/p>\n

[1] Yuan Xiao, Xiaokuan Zhang, Yinqian Zhang, and Radu Teodorescu,\u00a0One Bit Flips, One Cloud Flops: Cross-VM Row Hammer Attacks and Privilege Escalation,\u00a0https:\/\/www.usenix.org\/system\/files\/conference\/usenixsecurity16\/sec16_paper_xiao.pdf<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

\u4e91\u8ba1\u7b97\u4e2d\u8de8\u865a\u62df\u673a\u7684Row Hammer\u653b\u51fb\u548c\u6743\u9650\u63d0\u5347 One Bit Flips, One Clou… Continue reading → <\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-1316","post","type-post","status-publish","format-standard","hentry","category-research"],"_links":{"self":[{"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=\/wp\/v2\/posts\/1316","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1316"}],"version-history":[{"count":1,"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=\/wp\/v2\/posts\/1316\/revisions"}],"predecessor-version":[{"id":1320,"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=\/wp\/v2\/posts\/1316\/revisions\/1320"}],"wp:attachment":[{"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1316"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1316"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/202.112.238.40\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1316"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}