A fix is available
APAR status
Closed as program error.
Error description
Invalid HTTP response causes loop in DFHWBCL Application program is doing an E.C.WEB CONVERSE. A loop is caused by an invalid HTTP response received from the remote server. The HTTP headers are terminated by only a CR instead of a CRLF, and the headers end with a double CR instead of a double CRLF. . This invalid response has caused DFHWBCL to fail to find the end of the HTTP headers in the first 4K of data received. The code then ends up trying to receive more data into an already full 4K buffer and ends up looping making zero length receives. . If a valid HTTP response was received from the server then the loop would not occur.
Local fix
*
Problem summary
**************************************************************** * USERS AFFECTED: All CICS users. * **************************************************************** * PROBLEM DESCRIPTION: DFHWBCL enters a non-yielding infinite * * loop which can only be broken by * * recycling the CICS region. * **************************************************************** * RECOMMENDATION: * **************************************************************** If CICS receives more than 4K of HTTP header information, DFHWBCL will enter an infinite loop. The prescan_headers routine assumes that it will always find the CRLFCRLF sequence within 4K. If this does not occur, the loop is entered and will never yield. Only a CICS restart will break the loop.
Problem conclusion
DFHWBCL has been changed in routine prescan_headers so that if there is no more space in the buffer being used to peek the incoming data, the loop is exited with an exception response.
Temporary fix
FIX AVAILABLE BY PTF ONLY
Comments
APAR Information
APAR number
PM44057
Reported component name
CICSTS V3 Z/OS
Reported component ID
5655M1500
Reported release
500
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2011-07-21
Closed date
2011-09-15
Last modified date
2011-10-03
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
PM44423 UK72069
Modules/Macros
DESWBCL DFHWBCL
Fix information
Fixed component name
CICSTS V3 Z/OS
Fixed component ID
5655M1500
Applicable component levels
R500 PSY UK72069
UP11/10/01 P F109
Fix is available
Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.
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Document Information
Modified date:
03 October 2011