Bug #17102

"Found something that is not an ethernet packet" intermittent test failure

Added by intrigeri 2019-09-29 12:38:47 . Updated 2019-11-13 19:15:24 .

Status:
Resolved
Priority:
Elevated
Assignee:
Category:
Test suite
Target version:
Tails_4.1
Start date:
Due date:
% Done:

100%

Feature Branch:
test/17102-deduplicate-sniffers
Type of work:
Code
Blueprint:

Starter:
Affected tool:
Deliverable for:

Description

Looks like Bug #16825 is back, at least I’ve seen it once.

Files

03_38_46_The_MAC_address_is_not_leaked_when_booting_Tails.journal (453532 B) intrigeri, 2019-09-29 12:40:23

Subtasks

Related issues

Related to Tails - Bug #16825: "Found something that is not an ethernet packet" intermittent test failure Resolved
Related to Tails - Bug #16788: Tests fail with "Found something in the pcap file that either is non-IP, or cannot be parsed (RuntimeError)" Resolved
Blocks Tails - Feature #16209: Core work: Foundations Team Confirmed

History

#1 Updated by intrigeri 2019-09-29 12:39:39

#2 Updated by intrigeri 2019-09-29 12:39:47

  • related to Bug #16825: "Found something that is not an ethernet packet" intermittent test failure added

#3 Updated by intrigeri 2019-09-29 12:39:52

  • related to Bug #16788: Tests fail with "Found something in the pcap file that either is non-IP, or cannot be parsed (RuntimeError)" added

#4 Updated by intrigeri 2019-09-29 12:43:47

I can’t attach the pcap because it’s larger than the maximum size (5 MB) allowed here.

Here it is: https://jenkins.tails.boum.org/view/RM/job/test_Tails_ISO_devel/1894/artifact/build-artifacts/03%3A38%3A46_The_MAC_address_is_not_leaked_when_booting_Tails.pcap

I’ve also saved that file locally so that I can send it out of band to whoever will work on this.

I’ve tried opening it with Wireshark but that fails with “The capture file appears to be damaged or corrupt. (pcap: File has 34246810-byte packet, bigger than maximum of 262144)”.

#5 Updated by intrigeri 2019-10-11 04:19:40

intrigeri wrote:
> I’ve also saved that file locally so that I can send it out of band to whoever will work on this.
>
> I’ve tried opening it with Wireshark but that fails with “The capture file appears to be damaged or corrupt. (pcap: File has 34246810-byte packet, bigger than maximum of 262144)”.

Reproduced while testing 4.0~rc1, saved pcap locally, same issue in Wireshark as last time.

#6 Updated by intrigeri 2019-10-19 16:14:03

  • Priority changed from Normal to Elevated

This happens quite regularly these days, and it affects tons of scenarios so we can’t simply tag one or 3 of them as fragile ⇒ bumping priority.

#7 Updated by intrigeri 2019-11-12 07:36:02

  • Status changed from Confirmed to In Progress
  • Assignee set to intrigeri
  • Target version set to Tails_4.1
  • Feature Branch set to test/17102-deduplicate-sniffers

This made the last 3 test suite runs on the stable branch fail, so I took a closer look.

Every time the failing scenario is “The MAC address is not leaked when booting Tails”, which has one interesting property: in mac_spoofing.feature, we have “I capture all network traffic” as a Background step, but then this very scenario also has a “I capture all network traffic” step. That’s been the case since commit:2e13ad46fda71d55192e5946d7a36d9b3401fbb0. I understand it’s because for this very scenario, we want a complete boot instead of restoring a snapshot. But it seems to me that the current implementation results in having two tcpdump processes sniffing the same interface and writing to the same file, which could cause trouble.

#8 Updated by intrigeri 2019-11-12 07:59:59

intrigeri wrote:
> This happens quite regularly these days, and it affects tons of scenarios

I’m not so sure about the “it affects tons of scenarios” part. I wonder if I did check this when I wrote that. I propose we first fix the problem where it’s occurring super often, and if the problem comes back elsewhere, then we can reopen or file another ticket (just like we had Bug #16825 and Bug #16788 already, in the “fallout of our fix for Bug #16148” series).

#9 Updated by intrigeri 2019-11-13 09:50:30

  • Status changed from In Progress to Needs Validation
  • Assignee deleted (intrigeri)

In 5 test suite runs on this branch on Jenkins, this problem did not occur, while it happens almost every time on the stable branch.

#10 Updated by segfault 2019-11-13 19:15:24

  • Status changed from Needs Validation to Resolved
  • % Done changed from 0 to 100

Applied in changeset commit:tails|f1a1a9c301a24b755effd85df2ce171521c8f8fb.