Bug 992 – Unusual (possibly incorrect assertion) in Packet::Deserialize

Bug 992 - Unusual (possibly incorrect assertion) in Packet::Deserialize


Summary:	Unusual (possibly incorrect assertion) in Packet::Deserialize

Status:	RESOLVED FIXED

Product:	ns-3
Classification:	Unclassified
Component:	core
Version:	ns-3-dev
Hardware:	All All

Importance:	P5 minor
Assigned To:	Mathieu Lacage

URL:
Keywords:

Depends on:
Blocks:
	Show dependency tree / graph

Reported:	2010-09-16 00:10 UTC by Quincy Tse
Modified:	2010-09-29 17:22 UTC (History)
CC List:	2 users (show)

See Also:

Attachments
Proposed patch (1.39 KB, patch) 2010-09-16 00:13 UTC, Quincy Tse	Details \| Diff
Proposed patch. (1.44 KB, patch) 2010-09-16 00:14 UTC, Quincy Tse	Details \| Diff
Show Obsolete (1) Add an attachment (proposed patch, testcase, etc.)

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Description Quincy Tse 2010-09-16 00:10:29 UTC

../src/common/packet.cc:738:3: error: comparison of unsigned
      expression >= 0 is always true [-Wtautological-compare]

Same warning was also triggered in lines 767 and 787.

In Packet::Deserialize, size is uint32_t, thus always >=0 (NS_ASSERT line does not detect the buffer overflow).

Maybe the NS_ASSERTs should be something like the following?

== NS_ASSERT (size >= nixSize);
== NS_ASSERT (size >= metaSize);
== NS_ASSERT (size >= bufSize);

Comment 1 Quincy Tse 2010-09-16 00:13:32 UTC

Created attachment 973 [details]
Proposed patch

Comment 2 Quincy Tse 2010-09-16 00:14:38 UTC

Created attachment 974 [details]
Proposed patch.

Comment 3 Josh Pelkey 2010-09-29 17:22:51 UTC

(In reply to comment #2)
> Created an attachment (id=974) [details]
> Proposed patch.

You are right, and the patch is right.  I have applied: changeset 6d5c1c19bdfe

Thanks.