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Bug #2365

OsmoBTS sends empty frames on BCCH for TC=5

Added by laforge over 1 year ago. Updated over 1 year ago.

Status:
Closed
Priority:
Normal
Assignee:
Category:
-
Target version:
-
Start date:
07/15/2017
Due date:
% Done:

100%

Spec Reference:

Description

When no SI 2bis, nor 2ter, nor 2quater is in use, then the code in bts_sysinfo_get() will return null, causing the transmission of a dummy frame (0303012B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B) instead of a system information message. This is - at least - very odd and might not be backed by the specification. We should simply send any other system information message instead of sending a frame that does not have a valid SI header.

While 030301 might be a valid, empty UI frame on a DCCH, it is not a valid frame for the BCCH, where the header is structured differently.

In fact, bts_sysinfo_get() should never return NULL and always return a valid BCCH message.

This bug was found while developing http://git.osmocom.org/osmo-ttcn3-hacks/tree/sysinfo/Test.ttcn

History

#1 Updated by laforge over 1 year ago

#2 Updated by laforge over 1 year ago

  • Assignee changed from sysmocom to laforge
  • % Done changed from 0 to 80

Fix submitted as https://gerrit.osmocom.org/3259 - pending review.

http://git.osmocom.org/osmo-ttcn3-hacks/tree/sysinfo is being developed to catch bugs like this.

#3 Updated by laforge over 1 year ago

  • Status changed from New to Closed
  • % Done changed from 80 to 100

fix merged.

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