DB2 FOR LUW / DB2FORLUW / B50 - DB2

Traces shows Failure while decompressing.

Root Cause: Decompress logic while storing C block found that C
block present in current frame is less than CblockSize hence it
request for more source to decode and write to output buffer. In
this process the dest buffer was new and decompress will not
write anything and ask for next source buffer to complete
processing.
In caller we have a check for verifying that decompress logic
will not ask for more source when it is last buffer but the last
buffer check has not been done. The current check only checks
for source byte read and bytes written to output buffer.

To validate please repro failed ET command with
db2trc on -l 32M -m "*.*.EXTBL,SQLZ.*.*"

Either of the following two errors are indicative of the
problem:
===== 1 =====

452815      extblTransportFillMsgBufFile entry
452816      | sqlzLz4DeCompressStream entry
452817      | sqlzLz4DeCompressStream exit [rc = 0x870F01F2 =
-2029059598 = SQLO_COMPRESSION_FAILED]

        bytes 16

        Data1   (PD_TYPE_UINT,8) unsigned integer:
        0

452818      | ExtblController::setExtblRc entry
452819      | ExtblController::setExtblRc exit
452820      | ExtblController::setShutdownJobRc entry
452821      | | ExtblController::setExtblRc entry
452822      | | ExtblController::setExtblRc exit
452823      | ExtblController::setShutdownJobRc exit
452832      extblTransportFillMsgBufFile error [probe 2443] [
ZRC = 0x00000004 = 4]

===== 2 =====
9           sqlzBuildInstanceTopology entry [eduid 26857 eduname
db2agent]
10          sqlzBuildInstanceTopology exit
263         sqlzeMapZrc entry [eduid 26857 eduname db2agent]
264         | sqlzGetZRCInfo entry [eduid 26857 eduname
db2agent]
265         | sqlzGetZRCInfo exit [rc = 0x00000064 = 100 =
SQLUDI_RC_RECORD_WARNING]
266         sqlzeMapZrc errtrans [probe 40] [ ZRC = 0x80040001 =
-2147221503 = SQLD_NOREC -->  SQL0100  ]
267         sqlzeMapZrc error [probe 50] [ ZRC = 0x80040001 =
-2147221503 = SQLD_NOREC]

****************************************************************
* USERS AFFECTED:                                              *
* all                                                          *
****************************************************************
* PROBLEM DESCRIPTION:                                         *
* See Error Description                                        *
****************************************************************
* RECOMMENDATION:                                              *
* Upgrade to Db2 11.5.5.0 or higher                            *
****************************************************************

File is *NOT* corrupt, the problem is with reading code.
No workaround available.

****************************************************************
* USERS AFFECTED:                                              *
* all                                                          *
****************************************************************
* PROBLEM DESCRIPTION:                                         *
* See Error Description                                        *
****************************************************************
* RECOMMENDATION:                                              *
* Upgrade to Db2 11.5.5.0 or higher                            *
****************************************************************

Upgrade to Db2 11.5.5.0 or higher

Date  - problem reported    :
Date  - problem closed      :
Date  - last modified       :

08.09.2020
20.11.2020
20.11.2020