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rdsn: fix asio_rpc_session bug which may cause double free #115
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shengofsun
reviewed
Jun 29, 2018
include/dsn/utility/autoref_ptr.h
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| _magic = 0xfacedead; // 4207861421 | ||
| } | ||
| // 0xdeadbeef: 3735928559 | ||
| dassert(_magic == 0xdeadbeef, "memory corrupted, could be double free or others"); |
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utility下暂时先别用dassert了，我希望把utility做成不依赖rdsn环境的一个package。等后面把dassert剥离得可以不依赖rdsn runtime了，再慢慢引入吧。
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fixed, and add issue apache/incubator-pegasus#102
shengofsun
approved these changes
Jun 29, 2018
acelyc111
approved these changes
Jun 29, 2018
neverchanje
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type/bug-fix
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to fix #114
原因是：在asio_network_provider::do_accept()中，新建的asio_rpc_session的构造函数中，调用了start_read_next()，进一步调用 asio_rpc_session::do_read()：先add_ref()，如果立即调用回调函数，会release_ref()，如果该release_ref()发生在构造函数返回之前，这个新建的对象asio_rpc_session就会被立即析构。在构造函数返回之后，do_accept()中继续持有和使用该对象，就会造成double free。
解决办法：asio_rpc_session的构造函数中不调用start_read_next()，而是在对象创建完成后，在外面调用start_read_next()。