Bug 1016064

Summary: libndp: NDP option decoder issues
Product: Red Hat Enterprise Linux 7 Reporter: Florian Weimer <fweimer>
Component: libndpAssignee: Jiri Pirko <jpirko>
Status: CLOSED CURRENTRELEASE QA Contact: Hangbin Liu <haliu>
Severity: medium Docs Contact:
Priority: medium    
Version: 7.0CC: haliu, jpirko, qcai, rkhan
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: libndp-1.2-1.el7 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2014-06-13 09:41:42 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On:    
Bug Blocks: 1016060    

Description Florian Weimer 2013-10-07 12:31:11 UTC
In ndp_msg_check_opts() in libndp/libndp.c, this code is used to parse the option header:

		uint8_t cur_opt_raw_type = ptr[0];
		uint8_t cur_opt_len = ptr[1] << 3; /* convert to bytes */

The type of cur_opt_len is incorrect, it should be unsigned, so that large values are not clipped.  With the current code, libndp parsing gets out of sync with the payload and subsequent options are not recognized.

In addition, RFC 2461 requires that packets with zero-length options are silently discarded.  The code merely stops options processing at the first zero-length option.

Comment 2 Florian Weimer 2013-10-07 12:33:58 UTC
ndp_msg_next_opt_offset() has the same problem.

Comment 8 Ludek Smid 2014-06-13 09:41:42 UTC
This request was resolved in Red Hat Enterprise Linux 7.0.

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