{"id":40,"date":"2011-05-26T10:42:08","date_gmt":"2011-05-26T02:42:08","guid":{"rendered":"http:\/\/www.sulabs.net\/?p=40"},"modified":"2017-01-09T10:34:36","modified_gmt":"2017-01-09T02:34:36","slug":"%e7%94%a8gdb-%e8%b0%83%e8%af%95-php-segmentation-fault-%e9%94%99%e8%af%af","status":"publish","type":"post","link":"https:\/\/www.sulabs.net\/?p=40","title":{"rendered":"\u7528GDB \u8c03\u8bd5 PHP Segmentation fault \u9519\u8bef"},"content":{"rendered":"

\u8f6c\u81ea http:\/\/hi.baidu.com\/thinkinginlamp\/blog\/item\/5e8062d9744f012511df9b93.html<\/a><\/p>\n

Linux\u4e0b\uff0cSegmentation fault<\/a>\u5f88\u5e38\u89c1\uff0c\u6b64\u65f6\uff0c\u4f7f\u7528GDB\u8c03\u8bd5\u53ef\u4ee5\u5e2e\u52a9\u4f60\u786e\u5b9a\u51fa\u73b0\u9519\u8bef\u7684\u539f\u56e0\u3002<\/p>\n

\u6211\u4eec\u5148\u60f3\u529e\u6cd5\u91cd\u73b0\u4e00\u4e0bSegmentation fault\u73b0\u8c61\uff0c\u4e0b\u9762\u6211\u4eec\u5148\u4f7f\u7528Shell\u7684\u65b9\u5f0f\u6765\u8bd5\u9a8c\uff0c\u7f16\u5199demo.sh\u811a\u672c\uff1a<\/p>\n

#!\/bin\/bash
\nkill -s SEGV $$<\/span><\/p>\n

\u5176\u4e2d$$\u5c31\u662f\u811a\u672c\u7684\u8fdb\u7a0b\u53f7\uff0cSEGV\u4fe1\u53f7\u7684\u4f5c\u7528\u7b49\u540c\u4e8eSegmentation fault\uff0c\u6574\u53e5\u57fa\u672c\u610f\u601d\u5c31\u662f\u8ba9\u81ea\u5df1\u5d29\u6e83\u3002<\/p>\n

\u4fdd\u5b58\u597d\uff0c\u5e76\u4e14\u52a0\u4e0a\u6267\u884c\u6743\u9650\uff1achmod +x demo.sh<\/p>\n

# .\/demo.sh<\/strong>
\nSegmentation fault<\/span><\/p>\n

\u5728\u51fa\u73b0Segmentation fault\u7684\u65f6\u5019\uff0cLinux\u6709\u80fd\u529b\u751f\u6210\u4e00\u4efdCore Dump\u6587\u4ef6\uff0c\u6211\u4eec\u6fc0\u6d3b\u8fd9\u79cd\u80fd\u529b\uff1a<\/p>\n

# ulimit -c unlimited<\/strong><\/span><\/p>\n

\u751f\u6210\u7684Core Dump\u6587\u4ef6\u7684\u5177\u4f53\u4fe1\u606f\u53ef\u4ee5\u901a\u8fc7\u5982\u4e0b\u547d\u4ee4\u67e5\u770b\uff1a<\/p>\n

# cat \/proc\/sys\/kernel\/core_pattern<\/strong>
\ncore<\/span><\/p>\n

\u8fd9\u8868\u793a\u4f1a\u5728\u5f53\u524d\u76ee\u5f55\u751f\u6210core\u6587\u4ef6\uff0c\u63a5\u7740\u8fd0\u884c\u4e00\u6b21demo.sh\u6587\u4ef6\u5c31\u80fd\u751f\u6210core\u6587\u4ef6\u4e86\uff1a<\/p>\n

# .\/demo.sh<\/strong>
\nSegmentation fault (core dumped)
\n# ls<\/strong>
\ncore.16069<\/span><\/p>\n

\u4e0b\u9762\u5230\u4e86\u4f7f\u7528gdb\u7684\u65f6\u5019\u4e86\uff1a<\/p>\n

# gdb \/bin\/bash core.16069<\/strong>
\n(gdb) bt<\/strong>
\n#0 0x00c7c410 in __kernel_vsyscall ()
\n#1 0x00733146 in kill () from \/lib\/libc.so.6
\n#2 0x0807a561 in kill_pid ()
\n#3 0x080a2b9f in kill_builtin ()
\n#4 0x0806b81c in dispose_exec_redirects ()
\n#5 0x0806d010 in new_fd_bitmap ()
\n#6 0x0806dc17 in execute_command_internal ()
\n#7 0x0806f443 in execute_command ()
\n#8 0x0805ed21 in reader_loop ()
\n#9 0x0805e817 in main ()<\/span><\/p>\n

\u81f3\u4e8e\u8fd9\u4e9b\u5806\u6808\u4fe1\u606f\u600e\u4e48\u770b\u5c31\u9760\u4f60\u81ea\u5df1\u7684\u7ecf\u9a8c\u4e86\u3002<\/p>\n

\u4e0b\u9762\u518d\u770b\u4e00\u4e2aGDB\u8c03\u8bd5PHP\u811a\u672c\u7684\u4f8b\u5b50\uff1a\u4e00\u822c\u6765\u8bf4\uff0cPHP\u7a0b\u5e8f\u5458\u9047\u5230Segmentation fault\u7684\u60c5\u51b5\u5e76\u4e0d\u591a\uff0c\u4e0d\u8fc7\u6709\u65f6\u5019PHP\u5185\u90e8\u7684Bug\u8fd8\u662f\u53ef\u80fd\u89e6\u53d1\u8fd9\u7c7b\u9519\u8bef\uff0c\u800c\u4e14\u4e00\u65e6\u51fa\u73b0\uff0c\u6ca1\u6709\u660e\u786e\u7684\u9519\u8bef\u4fe1\u606f\uff0c\u4e0d\u6613\u786e\u5b9a\u539f\u56e0\u3002\u6211\u8fd9\u91cc\u4e3e\u7684\u4f8b\u5b50\u662f\u5f53\u524dCURL\u6a21\u5757\u7684\u4e00\u4e2aBug\uff0c\u7248\u672c\u4fe1\u606f\u662fPHP 5.2.9\uff0cCURL 7.15.5\u3002<\/p>\n

\u7f16\u5199\u811a\u672cdemo.php\uff1a<\/p>\n

<?php
\n$url = \"http:\/\/localhost\/\";<\/span><\/p>\n

$ch = curl_init();<\/p>\n

curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
\ncurl_setopt($ch, CURLOPT_POST, 1);
\ncurl_setopt($ch, CURLOPT_POSTFIELDS, array('Hello' => 'World'));
\ncurl_setopt($ch, CURLOPT_URL, $url);<\/p>\n

$copy = curl_copy_handle($ch);<\/p>\n

curl_close($ch);<\/p>\n

curl_exec($copy);<\/p>\n

curl_close($copy);
\n?><\/p>\n

\u6267\u884c\u811a\u672c\uff1a<\/p>\n

# php demo.php<\/strong>
\nSegmentation fault (core dumped)<\/span><\/p>\n

\u4e0d\u51fa\u6240\u6599\u7684\u8bdd\u5c31\u4f1a\u51fa\u73b0Segmentation fault\u9519\u8bef\uff0c\u8fd8\u6709Core Dump\u6587\u4ef6\u3002\u8fd9\u6b21\u6211\u4eec\u6362\u4e00\u4e2aGDB\u8c03\u7528\u65b9\u5f0f\uff1a<\/p>\n

# gdb php<\/strong>
\nGNU gdb Red Hat Linux (6.5-37.el5rh)
\nCopyright (C) 2006 Free Software Foundation, Inc.
\nGDB is free software, covered by the GNU General Public License, and you are
\nwelcome to change it and\/or distribute copies of it under certain conditions.
\nType \"show copying\" to see the conditions.
\nThere is absolutely no warranty for GDB. Type \"show warranty\" for details.
\nThis GDB was configured as \"i386-redhat-linux-gnu\"...Using host libthread_db library \"\/lib\/libthread_db.so.1\".<\/span><\/p>\n

(gdb) run demo.php<\/strong>
\nStarting program: \/usr\/local\/php\/bin\/php demo.php
\n[Thread debugging using libthread_db enabled]
\n[New Thread -1208236336 (LWP 11970)]<\/p>\n

Program received signal SIGSEGV, Segmentation fault.
\n[Switching to Thread -1208236336 (LWP 11970)]
\n0x010200a5 in memcpy () from \/lib\/libc.so.6
\n(gdb) bt<\/strong>
\n#0 0x010200a5 in memcpy () from \/lib\/libc.so.6
\n#1 0x002423b3 in Curl_FormBoundary () from \/usr\/lib\/libcurl.so.3
\n#2 0x0024268f in Curl_getFormData () from \/usr\/lib\/libcurl.so.3
\n#3 0x00247a13 in Curl_http () from \/usr\/lib\/libcurl.so.3
\n#4 0x002529b0 in Curl_do () from \/usr\/lib\/libcurl.so.3
\n#5 0x0025ebe7 in Curl_perform () from \/usr\/lib\/libcurl.so.3
\n#6 0x0025f1d9 in curl_easy_perform () from \/usr\/lib\/libcurl.so.3
\n#7 0x080c5808 in zif_curl_exec ...<\/p>\n

\u5982\u679c\u811a\u672c\u4ee3\u7801\u5f88\u591a\uff0c\u4ec0\u4e48mysql, gd, curl\u4e00\u5927\u5806\u7684\u8bdd\uff0c\u901a\u8fc7\u4e0a\u9762\u7684\u8c03\u8bd5\u4fe1\u606f\uff0c\u5e94\u8be5\u7acb\u523b\u5c31\u80fd\u5224\u65ad\u51fa\u662fCURL\u6a21\u5757\u7684\u95ee\u9898\uff0c\u8fd9\u65e0\u7591\u4f1a\u5927\u5927\u8282\u7701\u6211\u4eec\u7684\u65f6\u95f4\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"

\u8f6c\u81ea http:\/\/hi.baidu.com\/thinkinginlamp\/bl …<\/p>\n

\u7ee7\u7eed\u9605\u8bfb »<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-40","post","type-post","status-publish","format-standard","hentry","category-other"],"_links":{"self":[{"href":"https:\/\/www.sulabs.net\/index.php?rest_route=\/wp\/v2\/posts\/40","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sulabs.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sulabs.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sulabs.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sulabs.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=40"}],"version-history":[{"count":3,"href":"https:\/\/www.sulabs.net\/index.php?rest_route=\/wp\/v2\/posts\/40\/revisions"}],"predecessor-version":[{"id":740,"href":"https:\/\/www.sulabs.net\/index.php?rest_route=\/wp\/v2\/posts\/40\/revisions\/740"}],"wp:attachment":[{"href":"https:\/\/www.sulabs.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=40"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sulabs.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=40"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sulabs.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=40"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}