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 EDT by Quincy Tse
Modified:	2010-09-29 17:22 EDT (History)
CC List:	2 users (show)

See Also:

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

Note You need to log in before you can comment on or make changes to this bug.

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

../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 EDT

Created attachment 973 [details]
Proposed patch

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

Created attachment 974 [details]
Proposed patch.

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

(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.