Public bug reported:

Using the Trusty GA kernel, we found that when capturing network packets
with libpcap using a loop

    pcap_dispatch(handle, -1, dispatcher, NULL);
    select(fd + 1, & fd_selected, 0, 0, &timeval);

where timeval = 2s, packets are missed if they arrive at low rates.

I have a small test capture program (attached) which shows pings
not being captured on an otherwise idle network connection.

The problem does not occur on later (e.g. LTS Enablement Xenial)
kernels.

We believe the following fixes the cause:

https://github.com/torvalds/linux/commit/da413eec729dae5dcb150e2eb34c5e7e5e4e1b49

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-generic 3.13.0.121.131
ProcVersionSignature: Ubuntu 3.13.0-121.170-generic 3.13.11-ckt39
Uname: Linux 3.13.0-121-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.23
Architecture: amd64
AudioDevicesInUse:
 USER        PID ACCESS COMMAND
 /dev/snd/controlC0:  jim        2070 F.... pulseaudio
CurrentDesktop: Unity
Date: Tue Jun 27 11:32:11 2017
HibernationDevice: RESUME=UUID=532db246-2b7f-45e1-a3f1-18720bbb7349
InstallationDate: Installed on 2016-11-03 (235 days ago)
InstallationMedia: Ubuntu 14.04.5 LTS "Trusty Tahr" - Release amd64 (20160803)
IwConfig:
 eth0      no wireless extensions.
 
 lo        no wireless extensions.
Lsusb:
 Bus 001 Device 002: ID 80ee:0021 VirtualBox USB Tablet
 Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
MachineType: innotek GmbH VirtualBox
ProcFB: 0 VESA VGA
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-121-generic 
root=UUID=392afc20-cb81-4990-94f1-026ef649561f ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-121-generic N/A
 linux-backports-modules-3.13.0-121-generic  N/A
 linux-firmware                              1.127.23
RfKill:
 
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/01/2006
dmi.bios.vendor: innotek GmbH
dmi.bios.version: VirtualBox
dmi.board.name: VirtualBox
dmi.board.vendor: Oracle Corporation
dmi.board.version: 1.2
dmi.chassis.type: 1
dmi.chassis.vendor: Oracle Corporation
dmi.modalias: 
dmi:bvninnotekGmbH:bvrVirtualBox:bd12/01/2006:svninnotekGmbH:pnVirtualBox:pvr1.2:rvnOracleCorporation:rnVirtualBox:rvr1.2:cvnOracleCorporation:ct1:cvr:
dmi.product.name: VirtualBox
dmi.product.version: 1.2
dmi.sys.vendor: innotek GmbH

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: Confirmed


** Tags: amd64 apport-bug trusty

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https://bugs.launchpad.net/bugs/1700746

Title:
  select() on network device loses packets at low data rates

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