[ns] [bug] Mac header length is invalid

[Takuya Murakami]

[Bug Report]

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Category:  Other
Package:   ns 2.33
OS:        Linux
Environment Variables:
LD_LIBRARY_PATH=
TCL_LIBRARY=
TK_LIBRARY=


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Description:

Description of Problem:
1) In mac/mac.h, the MAC_HDR_LEN is defined as 64 (byte).
But struct hdr_mac is only 36 bytes. In mac-802_11.cc, some code initializes the area of hdr_mac with bzero() with length = MAC_HDR_LEN(64)!
Such kind of code destroys other headers.

2) In mac/mac-802_11.h, struct beacon_frame and proberep_frame are defined. The sizes of these headers exceeds sizeof(struct hdr_mac).
They uses same memory area with hdr_mac, so some other headers might be destroyd.

How Easily Reproducible:
Every time.

Steps to Reproduce:
Use Mac802_11.