No Problem in 4.15.0-32 and before. Problem since 4.15.0-33-generic with raw socket => EtherCAT/SOEM (Simple Open Ethercat Master).
I can confirm it's fixed in 4.15.0-38-generic (SOEM ok). -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1791893 Title: Trailing garbage data when sending on an AF_PACKET socket Status in linux package in Ubuntu: Fix Released Bug description: When sending an Ethernet frame on an packet socket (AF_PACKET, SOCK_RAW), an additional 14 bytes of trailing data is sent on the interface. The extra 14 bytes are present regardless of the packet size. The extra data could be garbage/uninitialised kernel memory. Expected result: The raw Ethernet frame is sent on the interface. Actual result: The raw Ethernet frame plus an additional 14 bytes of unknown data is sent on the interface. Steps to reproduce: The attached test program inject.c can be used to reproduce the issue. # In window 1. Send an EAP packet without any payload. gcc inject.c -o inject sudo ./inject lo # Simultaneously in window 2. Tcpdump shows a payload of 14 bytes. sudo tcpdump -i lo -enlx 07:45:45.005652 02:00:00:00:00:01 > 02:00:00:00:00:00, ethertype EAPOL (0x888e), length 28: EAP packet (0) v64, len 0 0x0000: 4000 0000 0000 0000 4000 0000 0000 Running strace on the "inject" program shows that send(2) is indeed called with the correct buffer size. The extra 14 bytes appear to be added by the kernel, and this might leak kernel memory. Ubuntu release: Ubuntu 18.04.1 LTS Package version: 4.15.0-33.36 The issue could not be reproduced on linux-image-4.15.0-22-generic or linux-image-4.15.0-23-generic. uname -a: Linux ubuntu 4.15.0-33-generic #36-Ubuntu SMP Wed Aug 15 16:00:05 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux --- ProblemType: Bug ApportVersion: 2.20.9-0ubuntu7.3 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: johan 1763 F.... pulseaudio CurrentDesktop: GNOME-Flashback:GNOME DistroRelease: Ubuntu 18.04 HibernationDevice: RESUME=UUID=7d5f82e0-635f-4c53-a80d-11b0f47d27fd InstallationDate: Installed on 2018-01-08 (245 days ago) InstallationMedia: Ubuntu 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801) IwConfig: lxcbr0 no wireless extensions. enp0s3 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 Package: linux (not installed) ProcFB: 0 vboxdrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-33-generic root=UUID=54834e7a-dbec-4d9f-b662-6107cecc8a86 ro quiet splash ProcVersionSignature: Ubuntu 4.15.0-33.36-generic 4.15.18 RelatedPackageVersions: linux-restricted-modules-4.15.0-33-generic N/A linux-backports-modules-4.15.0-33-generic N/A linux-firmware 1.173.1 RfKill: StagingDrivers: vboxvideo Tags: bionic staging Uname: Linux 4.15.0-33-generic x86_64 UpgradeStatus: Upgraded to bionic on 2018-06-27 (76 days ago) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo wireshark _MarkForUpload: True 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.family: Virtual Machine dmi.product.name: VirtualBox dmi.product.version: 1.2 dmi.sys.vendor: innotek GmbH To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1791893/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
