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has any plan to support mysql8.0? #4

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quqiufeng opened this issue Nov 1, 2018 · 1 comment
Closed

has any plan to support mysql8.0? #4

quqiufeng opened this issue Nov 1, 2018 · 1 comment

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@quqiufeng
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@BohuTANG
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BohuTANG commented Nov 1, 2018

@quqiufeng

We are waiting the upstream branch ready:
https://github.com/percona/percona-server/tree/8.0

TCeason pushed a commit to TCeason/tokudb that referenced this issue Apr 2, 2019
Upstream commit ID : fb-mysql-5.6.35/8cb1dc836b68f1f13e8b2655b2b8cb2d57f400b3
PS-5217 : Merge fb-prod201803

Summary:
Original report: https://jira.mariadb.org/browse/MDEV-15816

To reproduce this bug just following below steps,

client 1:
USE test;
CREATE TABLE t1 (i INT) ENGINE=MyISAM;
HANDLER t1 OPEN h;
CREATE TABLE t2 (i INT) ENGINE=RocksDB;
LOCK TABLES t2 WRITE;

client 2:
FLUSH TABLES WITH READ LOCK;

client 1:
INSERT INTO t2 VALUES (1);

So client 1 acquired the lock and set m_lock_rows = RDB_LOCK_WRITE.
Then client 2 calls store_lock(TL_IGNORE) and m_lock_rows was wrongly
set to RDB_LOCK_NONE, as below

```
 #0  myrocks::ha_rocksdb::store_lock (this=0x7fffbc03c7c8, thd=0x7fffc0000ba0, to=0x7fffc0011220, lock_type=TL_IGNORE)
 #1  get_lock_data (thd=0x7fffc0000ba0, table_ptr=0x7fffe84b7d20, count=1, flags=2)
 #2  mysql_lock_abort_for_thread (thd=0x7fffc0000ba0, table=0x7fffbc03bbc0)
 xelabs#3  THD::notify_shared_lock (this=0x7fffc0000ba0, ctx_in_use=0x7fffbc000bd8, needs_thr_lock_abort=true)
 xelabs#4  MDL_lock::notify_conflicting_locks (this=0x555557a82380, ctx=0x7fffc0000cc8)
 xelabs#5  MDL_context::acquire_lock (this=0x7fffc0000cc8, mdl_request=0x7fffe84b8350, lock_wait_timeout=2)
 xelabs#6  Global_read_lock::lock_global_read_lock (this=0x7fffc0003fe0, thd=0x7fffc0000ba0)
```

Finally, client 1 "INSERT INTO..." hits the Assertion 'm_lock_rows == RDB_LOCK_WRITE'
failed in myrocks::ha_rocksdb::write_row()

Fix this bug by not setting m_locks_rows if lock_type == TL_IGNORE.

Closes facebook/mysql-5.6#838
Pull Request resolved: facebook/mysql-5.6#871

Differential Revision: D9417382

Pulled By: lth

fbshipit-source-id: c36c164e06c
TCeason pushed a commit to TCeason/tokudb that referenced this issue Jun 17, 2019
…E TO A SERVER

Problem
========================================================================
Running the GCS tests with ASAN seldomly reports a user-after-free of
the server reference that the acceptor_learner_task uses.

Here is an excerpt of ASAN's output:

==43936==ERROR: AddressSanitizer: heap-use-after-free on address 0x63100021c840 at pc 0x000000530ff8 bp 0x7fc0427e8530 sp 0x7fc0427e8520
WRITE of size 8 at 0x63100021c840 thread T3
    #0 0x530ff7 in server_detected /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_transport.c:962
    #1 0x533814 in buffered_read_bytes /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_transport.c:1249
    #2 0x5481af in buffered_read_msg /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_transport.c:1399
    xelabs#3 0x51e171 in acceptor_learner_task /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:4690
    xelabs#4 0x562357 in task_loop /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/task.c:1140
    xelabs#5 0x5003b2 in xcom_taskmain2 /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:1324
    xelabs#6 0x6a278a in Gcs_xcom_proxy_impl::xcom_init(unsigned short, node_address*) /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/gcs_xcom_proxy.cc:164
    xelabs#7 0x59b3c1 in xcom_taskmain_startup /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/gcs_xcom_control_interface.cc:107
    xelabs#8 0x7fc04a2e4dd4 in start_thread (/lib64/libpthread.so.0+0x7dd4)
    xelabs#9 0x7fc047ff2bfc in __clone (/lib64/libc.so.6+0xfebfc)

0x63100021c840 is located 64 bytes inside of 65688-byte region [0x63100021c800,0x63100022c898)
freed by thread T3 here:
    #0 0x7fc04a5d7508 in __interceptor_free (/lib64/libasan.so.4+0xde508)
    #1 0x52cf86 in freesrv /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_transport.c:836
    #2 0x52ea78 in srv_unref /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_transport.c:868
    xelabs#3 0x524c30 in reply_handler_task /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:4914
    xelabs#4 0x562357 in task_loop /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/task.c:1140
    xelabs#5 0x5003b2 in xcom_taskmain2 /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:1324
    xelabs#6 0x6a278a in Gcs_xcom_proxy_impl::xcom_init(unsigned short, node_address*) /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/gcs_xcom_proxy.cc:164
    xelabs#7 0x59b3c1 in xcom_taskmain_startup /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/gcs_xcom_control_interface.cc:107
    xelabs#8 0x7fc04a2e4dd4 in start_thread (/lib64/libpthread.so.0+0x7dd4)

previously allocated by thread T3 here:
    #0 0x7fc04a5d7a88 in __interceptor_calloc (/lib64/libasan.so.4+0xdea88)
    #1 0x543604 in mksrv /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_transport.c:721
    #2 0x543b4c in addsrv /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_transport.c:755
    xelabs#3 0x54af61 in update_servers /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_transport.c:1747
    xelabs#4 0x501082 in site_install_action /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:1572
    xelabs#5 0x55447c in import_config /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/site_def.c:486
    xelabs#6 0x506dfc in handle_x_snapshot /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:5257
    xelabs#7 0x50c444 in xcom_fsm /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:5325
    xelabs#8 0x516c36 in dispatch_op /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:4510
    xelabs#9 0x521997 in acceptor_learner_task /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:4772
    xelabs#10 0x562357 in task_loop /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/task.c:1140
    xelabs#11 0x5003b2 in xcom_taskmain2 /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/xcom/xcom_base.c:1324
    xelabs#12 0x6a278a in Gcs_xcom_proxy_impl::xcom_init(unsigned short, node_address*) /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/gcs_xcom_proxy.cc:164
    xelabs#13 0x59b3c1 in xcom_taskmain_startup /home/tvale/mysql/plugin/group_replication/libmysqlgcs/src/bindings/xcom/gcs_xcom_control_interface.cc:107
    xelabs#14 0x7fc04a2e4dd4 in start_thread (/lib64/libpthread.so.0+0x7dd4)

Analysis
========================================================================
The server structure is reference counted by the associated sender_task
and reply_handler_task.
When they finish, they unreference the server, which leads to its memory
being freed.

However, the acceptor_learner_task keeps a "naked" reference to the
server structure.
Under the right ordering of operations, i.e. the sender_task and
reply_handler_task terminating after the acceptor_learner_task acquires,
but before it uses, the reference to the server structure, leads to the
acceptor_learner_task accessing the server structure after it has been
freed.

Solution
========================================================================
Let the acceptor_learner_task also reference count the server structure
so it is not freed while still in use.

Reviewed-by: André Negrão <andre.negrao@oracle.com>
Reviewed-by: Venkatesh Venugopal <venkatesh.venugopal@oracle.com>
RB: 21209
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